<
55
 PRELIMINARY  RESULTS
          OF THE
NATIONWIDE  URBAN RUNOFF PROGRAM
LU
             VOLUME li - APPENDICES
             Water Planning Division
         U.S. Environmental Protection Agency
             Washington, D.C. 20460

-------
         PRELIMINARY RESULTS




               OF THE



   NATIONWIDE URBAN RUNOFF PROGRAM
            March 1, 1982
       VOLUME II - APPENDICES
       Water Planning Division



U.S.  Environmental Protection Agency



       Washington, D.C.   20460

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                         DISCLAIMER

     This report  has  been reviewed by the U.S. Environmental
Protection  Agency and  approved  for release.   Approval  does
not  signify   that   the  contents  necessarily  reflect  any
policies  or decisions  of the U.S.  Environmental  Protection
Agency  or  any of  its  offices,  grantees,  contractors,  or
subcontractors.

-------
                                  VOLUME I
                              TABLE OF CONTENTS

Chapter                                                                  Page
             Foreword	      iii
             Preface	        v
             Acknowledgements 	      vii
   1         INTRODUCTION	      1-1
   2         BACKGROUND	      2-1
             Early Perceptions	      2-1
             Conclusions From Section 208 Efforts 	      2-2
             ORD Efforts	      2-4
             Other Prior/Ongoing Efforts  	      2-5
             Discussion	      2-5
             The Nationwide Urban Runoff Program  	      2-G
   3         URBAN RUNOFF PERSPECTIVES  	      3-1
             Water Quantity Concerns  	      3-1
             Water Quality Concerns 	      3-2
             Water Quantity and Quality Control 	      3-3
             Problem Definition 	      3-4
   4         METHOD OF ANALYSIS	      4-1
             Introduction	      4-1
             Urban Runoff Pollutant Loads   	      4-1
             Water Quality Effects	      4-4
             Evaluation of Controls 	     4-13
             Quality Assurance and Quality Control  	     4-15
   5         FINDINGS	      5-1
             Introduction 	      5-1
             Loadings	      5-2

-------
                         TABLE OF CONTENTS (Cont'd)
Chapter
   6
   7
Figure
 5-la
 5-lb
 5-2

 5-3
 5-4

 5-5
 5-6

 5-7
 5-8
 5-9

 5-10

 5-11

 5-12

 5-13
 5-14
                                                            Page
Receiving Water Effects  	     5-27
Evaluation of Controls   	     5-54
Project Findings 	     5-59
CONCLUSIONS TO DATE	      6-1
REFERENCES	      7-1


                  LIST OF FIGURES

                                                            Page
Cumulative Probability Plots in Log-Space  	      5-5
Cumulative Probability Plots in Log-Space  	      5-6
Pollutant Concentration in Urban Runoff Event Means
(Preliminary NURP Data - 13 Projects)	      5-7
Comparison of NURP Results with Other Studies  	     5-10
Urban Runoff Concentration Ranges for NURP
Pilot Data	     5-12
Zonal Differences in Event Mean Concentrations 	     5-18
Contours of Long Term Storm Event Average Rainfall
Intensity for the Period June-September  	     5-29
Regional Value of Average Annual Stream Flow 	     5-30
Schematic of Rapid City Stream System  	     5-33
Distribution of Lead Concentrations in Rapid City
During Storm Runoff Periods (Preliminary
Projection)	     5-36
Mean Recurrence Interval of Indicated Storm Event
Averaged Stream Concentration  	     5-37
Effect of Urban Runoff Control on Distribution of
Lead Concentration in Streams	     5-40
Effects of Urban Runoff Control on Lead
Concentrations 	     5-41
Copper Concentration in Urban Runoff 	     5-43
Copper - Mean Recurrence Interval of Indicated Storm
Event Averaged Stream Concentrations - End-of-Pipe  .  .  .     5-45
                                      IV

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                          LIST OF FIGURES (Cont'd)


Figure                                                                   Page

 5-15        Copper - Mean Recurrence Interval of Indicated Storm
             Event Averaged Stream Concentrations - DAR 10	    5-46

 5-16        Copper - Mean Recurrence Interval of Indicated Storm
             Event Averaged Stream Concentrations - DAR 50    ....    5-47

 5-17        Copper - Mean Recurrence Interval of Indicated Storm
             Event Averaged Stream Concentrations - DAR-100 	    5-48

 5-18        Lead - Mean Recurrence Interval of Indicated Storm
             Event Averaged Stream Concentration  	    5-50
 5-19        Zinc - Mean Recurrence Interval of Indicated Storm
             Event Averaged Stream Concentration  	    5-51

 5-20        Cadmium - Mean Recurrence Interval of Indicated Storm
             Event Averaged Stream Concentration  	    5-52

 5-21        Chromium - Mean Recurrence Interval of Indicated Storm
             Event Averaged Stream Concentration  	    5-53
                               LIST OF TABLES
Table                                                                    Page

 4-1         Summary of Receiving Water Target Concentrations
             Used in Screening Analysis - Toxic Substances  	     4-8

 5-1         Sources of Data	     5-4

 5-2         Comparison of Preliminary NURP Data With
             Prior Summaries	     5-8

 5-3         Duncan's Multiple Range Test (a = 0.5)	    5-15

 5-4         Data Set Attributes By Zone	    5-16

 5-5         Data as a Ratio of Total Population Median
             by Zone	    5-17

 5-6         Data as a Ratio of Total Population Median
             by Season	    5-19

 5-7         Data as a Ratio of Total Population Median
             by Rainfall	    5-21

 5-8         Data as a Ratio of Total Population Median
             by Land Use	    5-22

-------
                           LIST OE TABLES (Cont'd)
Table

 5-9


 5-10


 5-11


 5-12


 5-13


 5-14
Average Storm and lime Between Storms for
Selected Locations in the U.S	
Percent Removal Effectiveness for the
Iraver Creek Detention Basin 	
Overall Percent Removal Effectiveness for
Selected NURP Detention Basins 	
Percent Removal Effectiveness for Pooled Detention
Basin Data   	
Summary of Lead Statistics for Winston-Salem NURP
Project  	

Percent Removal Effectiveness for Pooled
Street Sweeping Data ... 	
                                                            Page
5-28
5-55
5-56
5-57
5-58
                                                                         5-59
                                  VOLUME II

                              TABLE OF CONTENTS
Appendix

   A         Selected Site Characteristics  .  .

   B         Selected Event Data  	

   C         Data Analysis Methodologies  .  .  .

   D         Wet Weather Water Quality Criteria

   E         Project Summaries  	
   E         Priority Pollutant Report  ....

   G         Project Descriptions 	

   H         ORD Report 	
                                                             A-l

                                                             B-l

                                                             C-l

                                                             0-1

                                                             E-l

                                                             E-l

                                                             G-l

                                                             H-l
                                     VI

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         APPENDIX A



SELECTED SITE CHARACTERISTICS
           A-l

-------
                                    APPENDIX A
                                     FOREWORD


This appendix contains selected monitoring site characteristics data for those
projects that were included in the data analysis up to this point.  Referred to as
Fixed Site Data, the information selected for inclusion in this appendix is
analyzed in columns as follows:

PROJECT

     Code - A unique alphanumeric code number that identifies each of the 28 NURP
            projects in the NURP STORET data base (see listing that follows).

     Name - The urban area in which the NURP project is located.

CATCHMENT

     Code - A unique alphanumeric code number assigned by individual NURP projects
            to each monitoring site used, as entered in the NURP STORET data base.

     Name - The name by which the monitoring site is known within each project.

AREA

            The size of the contributing drainage area at the monitoring site;
            expressed in acres (multiply by 0.4047 to obtain hectares).
LAND USE
            The percentage of the total drainage area that is predominantely used
            as residential, commercial, industrial, or parkland/open (see listing
            that follows).
POPULATION DENSITY
SLOPE
            The population density in the catchment calculated by dividing the
            total population residing within the contributing drainage basin by
            its area in acres; expressed as persons per acre (multiply by 2.471
            to obtain persons per hectare).
            A measure of the representative catchment slope; expressed in feet
            per mile (multiply by 0.0001893 to obtain percent).
                                      A-2

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            NATIONWIDE URBAN RUNOFF PROJECT LOCATIONS
                      NURP PROJECTS

1.DURHAM, NEW HAMPSHIRE                                 NH1
2.LAKE QUINSIGAMONO, MASSACHUSETTS                      MAI
3.MYSTIC RIVER, MASSACHUSETTS                           MA2
A.LONG ISLAND, NEW  YORK                       .          NY1
5.LAKE GEORGE, NEW  YORK     .                            NY2
6.IRONOEQUQIT BAY,  NEW YORK                             NY3
7.METRO WASHINGTON, O.C.                                OC1
8.BALTIMORE, MARYLAND.                                   M01
9.MYRTLE BEACH, SOUTH CAROLINA                          SCI
10.WINSTON-SALEH , NORTH CAROLINA                          NCI
11.TAMPA, FLORIDA                                       FL1
12.KNOXYILLE, TENNESSEE                                 TNI
13.LANSING.  MICHIGAN                                    Mil
14.OAKLAND COUNTY,  MICHIGAN                             MI2
15.ANN ARBOR, MICHIGAN                                  MI3
16.CHAMPAIGN-URBANA, ILLINOIS                           I LI
17.CHICAGO,  ILLINOIS                                    IL2
18.MILWAUKEE, WISCONSIN'                                WI1
19.AUSTIN, TEXAS                                        TX1
20.LITTLE ROCK, ARKANSAS                                AR1
21.KANSAS CITY, KANSAS                                  KS1
22.DENVER, COLORADO                                    C01
23.SALT LAKE CITY,  UTAH                                 UT1
24.RAPID CITY*  SOUTH DAKOTA                             SD1
25.CASTRO VALLEY,  CALIFORNIA                           CA1
26.FRESNO, CALIFORNIA                                   CA2
27.BELLEVUE, WASHINGTON                                 WAI
28.EUGENE, OREGON                                       QRl

                     NON-NURP PROJECTS

29.MINNEAPOLIS,  MINNESOTA                              MN1
30.0ES  MOINES,  IOWA                                     IA1
31.TOPEKA, KANSAS                                       KS2
32.RENO,  NEVADA                                         NVl
33.SALEM,  OREGON                                        OR2
34.DALLAS, TEXAS  ..                                        TX2
                            A-3

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                       LAND USE COOES
URBAN RESIDENTIAL
URBAN RESIDENTIAL
URBAN RESIDENTIAL
URBAN RESIDENTIAL

URBAN COMMERCIAL
URBAN COMMERCIAL
URBAN COMMERCIAL

URBAN INDUSTRIAL
URBAN INDUSTRIAL
URBAN INDUSTRIAL
                  K.5 DWELLING UNITS/ACRE)
                  1.5 TO 2 DWELLING UNITS/ACRE)
                  (2.5 TO B DUELLING UNITS/ACRE)
                  (>8 DWELLING UNITS/ACRE)

                 (CENTRAL BUSINESS DISTRICT)
                 (LINEAR STRIP DEVELOPMENT)
                 (SHOPPING CENTER)

                 (LIGHT)
                 (MODERATE)
                 (HEAVY)
URBAN PARKLAND  OR  OPEN  SPACE
URBAN INSTITUTIONAL
URBAN UNDER CONSTRUCTION

AGRICULTURE
RANGELANO
FOREST
WATER,
WATER,
       STREAMS
       LAKES
AND CANALS
HA I Cl\ , UAKC3
WATER, RESERVOIRS
WATER, BAYS AND ESTUARIES
WATER, OCEANS
 WETLANDS
 BARREN
1110
1120
1130
                                               1100
1201
1202
1203

1301
1302
1303

1400
1401
1500

2000
3000
4000

5100
5200
5300
5400
5500

6000
7000
}
}
                                               1200
                                               1300
                                                              1400
                                A-4

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                                            NATIONWIDE  URBAN  RUNOFF  PROGRAM
                                          FIXED-SITE  DATA  FOR FASTTRACK FILE
PROJECT
CODE
NH 1
MA 1





DC 1













NC 1

IL 1




IL 2
MI 1


NAME
Durham
Lake Q.





WASH COG













Win. Sim.

Champaign




6. Ellyn
Lansing


CATCHMENT
CODE
1 PKG
PI
P2
P3
P4
P5
P6
001
002
003
004
006
007
008
009
010
on
103
106
107
110
NC1013
NC1023
B01
B02
B03
804
805
001
001
002
ORO
NAME
Parking Lot
Jordon P
Rte 9
Locust Ave.
Guua St.
Convent
Tilly Br.
St.W.O.
Ouf
Wen R.P.
F.R. Rd Se.
Stdw DP
Lake DP
Danrge I.T.
Rocky CCPP
Bulk Mail
Burke V.
Westly RP.
Sted. DP
Lake DP
Bulk Mail
C.B.D.
Ardmore
Matt is N
Mattis S.
J & D
John St. S.
John N.
Lake Ellyn
B.S.D.
B.S.D.
B.S.O.
AREA
AC
.9
110
338
154
601
100
1690
8.46
11.84
47.9
18.8
34.4
97.8
1.96
4.2
20.1
4.5
40.95
27.4
77.7
19
23
324
16.66
27.6
1.38
39.2
54
534
452.6
63
127.6
LANDUSE DISTRIBUTION (X OF TOTAL AREA)
1100
—
78
47
85
66
8
20
100
100
84
88
66
54
100
.
.
82
92
78
54
54
0
84
43
90
100
90
100
83
48
.
46
1200
100
16
24
1
2
63
7
_
.
.
.
-
.
-
.
.
-
-
-
-
-
100
2
57
10
-
-
-
5
5
.
14
1300
.
4
11
8
1
0
2
_
_
.
.
.
_
.
.
_
.
.
.
-
.
0
-
-
_
-
-
-
-
19
100
-
1400

2
18
5
31
29
58
_
.
16
12
34
46
-
100
100
18
8
22
46
46
0
12
.
_
-
10
.
12
28 .
.
40
Other

.
.
_
_
_
12 Wdland
_
.
_
_
_
_
.
_
..
_
_
_
.
_
_
_
_
_
.
_
_
.
_
_
-
POP/DEN
PER/ AC
0
N.D.
N.D.
N.O.
N.D.
N.D.
N.D.
N.D.
N.D.
N.D.
N.D.
N.D.
N.D.
N.O.
N.D.
N.D.
N.D.
N.D.
N.D.
N.O.
N.O.
N.D.
N.D.
3.0
21.74
21.7
18.37
18.38
7.87
4.97
0
4.31
CATCHMENT
SLOPE FT/MI
58.
N.D.
N.O.
N.D.
N.D.
N.O.
N.D.
84.5
450
195
227
248
420
190
135
N.D.
85
195
248
420
N.O.
N.D.
N.O.
187
549
90.0
62
30.6
49
221
132
121
en

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                                              NATIONWIDE  URBAN RUNOFF PROGRAM
                                        FIXED-SITE  DATA FOR  FASTTRACK FILE (CONT'D)
PROJECT
CODE
MI 1




MI 3











WI 1







TX 1


CO 1



NAME
Lansing
(CONTINUED)



Ann Arbor











Milwaukee







Austin


Denver



CATCHMENT
CODE
OR I
GCO
GCI
UPI
UP2
001
002
003
004
005
006
007
008
009
010
Oil
012
630
631
632
633
634
635
636
637
001
002
003
001
002
003
004
NAME
B.S.D.
B.S.D.
B.S.D.
B.S.D.
B.S.O.
Pitt AA(1)S
Pitt AA(RB)N
Pitt AA(RB)0
Pitt S-AARO
SR Wetld INT.
SR Wetld OOT.
Swift Run ORD
Traver CKO
Traver CK RBI
Traver CK RBO
NCampus DOR
Allen OR OTR
St. Fair
Wood CTR.
N. Hastings
N. Burbank
Rustler
Post Off.
Lincbler Cr.
West Congress
Northwest
Rolling wd
Turkey Ck
50th & Den
19th & Den
Cherry Ck.
Lake Den
AREA
AC
112.7
67
30.3
163.9
74.9
2001
2871
4872
6363
1207
1227
3075
4402
2303
2327
1541
3800
29
44.9
32.84
62.6
12.44
12.08
36.1
33.04
377.71
60.21
1297
L 19900
.08329
15817
10440
LANDUSE DISTRIBUTION (X OF TOTAL AREA)
1100
38
30
67
55
48
31
55
45
48
53
53
50
15
8
8
46
58
26
31
100
100
100
-
97
93
99
100
4
43
42
42
55
1200
16
15
33
-
_
23
10
15
14
1
1
4
1
-
-
16
9
74
56
-
-
-
100
3
7
1
-
-
13
12
16
23
1300
_
.
.
10
22
7
3
4
3
1
1
1
2
2
2
-
2
-
13
-
-
-
-
-
-
-
-
-
6
5
5
2
1400
46
55
.
35
40
24
21
23
25
15
15
33
35
.
1
38
31
-
-
-
-
-
-
-
-
-
-
96
38
40
38
20
Other
_
. -
.
-
-
15
11
13
10
30
30
12
47
90
89
-
.
-
-
-
-
-
-
.
-
-
-
-
-
_
-
-
POP/DEN
PER/ AC
4.26
5.07
5.07
5.19
4.94
1.9
6.54
4.64
4.35
2.24
2.24
3.51
1.91
.07
.07
1.82
9.39
10.
.03
17.05
14.62
0
0
18.01
16.34
9.27
3.32
.05
4.85
4.29
6.22
4.83
CATCHMENT
SLOPE FT/MI
233
200
121
226
194
33.8
60.7
45.5
61.6
32.1
32.1
39.6
58.6
33.2
33.2
89.8
82.0
160.
160.






237.6
260
396.0
248.
261
183
316
01

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                                              NATIONWIDE URBAN RUNOFF PROGRAM
                                        FIXED-SITE DATA FOR FASTTRACK FILE (CONT'D)
PROJECT
CODE
CO 1



MA 1

SD 1





NAME
Denver
(CONTINUED)



Bellevue

Rapid City





CATCHMENT
CODE
005
006
007
008
009
001
002
001
002
003
004
005
006
NAME
Weir Gulch
Sandrsn G
Hrvd G.
Bear Ck.
SoPlat Lit.
Lake Hills
Sorry Downs
RpdCk Abv CLake
RpdCk Abv WTP
RpdCk AtRpd Cty
RpdCk AtE MnSt
RpdCk BloHtnDh
MeideDnRpdCty
AREA
AC
4786
4715
2833
14603
N.D.
101.7
95.1
33574
20877
3872
3540
1606
1760
LANDUSE DISTRIBUTION (X OF TOTAL AREA)
1100
64
66
72
34
_
90
100
4
16
2
36
20
55
1200
10
13
16
9
_
_
_
.
_
13
14
26
7
1300
1
2
1
2
_
.
_
_
_
5
_
_

1400
25
19
11
10

10

_
5
20
15
35
14
Other
-
_
tonst. 45

_ •
_
96 Forest
79
60
35
19
24
POP/DEN
PER/ AC
7.64
9.57
7.72
2.91
N.D.
11.7
8.64
N.D.
N.D.
N.D.
N.D.
N.D.
N.D.
CATCHMENT
SLOPE FT/MI
240
168
143
444
N.D.
317
475
N.D.
N.D.
N.D.
N.D.
N.D.
N.O.'
3=-

00

cr

(U

-------
    APPENDIX B



SELECTED EVENT DATA
      B-l

-------
    FAST«TRACK OATA
                                       PROJECT   NCI
                                                        FASTTRACK LOAP P«TA

                                                           SITEIfi    "2074550
                                                                                                  16118 MONDAY! JANUARY a, 1982   52
    EVENT
    START
    TIMF
PRECIPITATION  COO            TSS            PHOSPHORUS     LEAD           COPPER
(INCHES)       MILLIGRAMS     MULI"R»MS     MILLIGRAMS     MILLIGRAMS     MILLIGRAMS
               PEP LITER      PER L'TFM      PER LITER      PER LITER      PER LITER
    01/17/80
    01/24/80
    oa/08/80
    04/24/80
    04/24/80
    05/io/eo
    05/14/80
    08/21/80
    09/29/80
    I0/2a/80
    M/oo/80
    M/17/80
    12/09/80
    oi/21/et
    02/02/81
    02/OT/8I
    02/10/81
    02/18/81
    05/00/81
    01/10/81
    00/10/81

SITl MEAN
SITE COEFFICIENT f!F VARIATION

NUMBER OF EVENT* FOB THIS STATION
1. 01
1.11
0.2A
0.25
0.18
O.ST
0.25
00S!
0.78
1.21
0.8
0.71
0.24
0.19
O.S1
0.04
1.29
1.21
0,74
1.11
0.12
0.67881*9
0.980660?
9T
0
9
146

246
107
a
^
t


02
g
(

81
28
86
60
177
t IS. 178
0.9096254
€
25
la
182
11!
600
06
41
21«0
282
17
8!
18
110
212
70
77
5!
78
10?
110
229. 0«1
1. 61168!
B
0.11
0.25
0.55
0.21
1.95
0.70
0.20
0.0
0.21
0.22
0.17
0.17
0.70
o.«
0.06
0.1
0.2
0.26
0.10
0.90
0.0110559
0.7861550
^
0.05
0.111
0.258
0,275
1.687
0.211
0.181
0.118
0.119
0.111
0.150
0.146
0.722
0.751
l.Ot
0.75
0.274
0.279
0.68
1.070
0.4886075
1.110016
.
0.02
0.065 .
0.078
0.061
0.195
0.015
0.065
0.071
0.067
0.016
0.012
0.057
0.117
0.09
0.075
0,062
0.077
0.011
0.075
0.157
0.0701111*
0.586289*
    FAST«TRACK DATA
                                       PROJECT   NCI
                                                        FASTTRACK LOAP f>ATA

                                                           3ITEIO    "2385000
                                                                                                  16118 MONOAV. JANUARY 4,  1982   11
    EVENT
    START
    TIME
PRECIPITATION  CHO            TSS            PHOSPHORUS     LEAD           COPPER
(INCHES)       MILLIGRAMS     »ILLII-»»MS     MILLIGRAMS     MILLIGRAMS     MILLIGRAMS
               PER LITER      PER L'TFH      PER LITER      PER LITER      PER LITER
    01/17/80
    00/20/80
    01/29/80
    05/10/80
    06/29/80
    07/09/80
    07/10/80
    07/12/80
    07/12/80
    08/21/80
    08/22/80
    09/20/80
    09/24/80
    10/20/80
    10/28/80
    11/00/80
    11/15/80
    11/17/80
    11/20/80
    12/04/80
    01/21/81
    01/00/81
    01/10/81
    00/10/81

SITE MEAN
SITE COEFFICIENT Or VARIATION

NUMBER OF EVENTS FOB THIS STATIC)*
1
0.28
0.18
0.56
0.14
1.25
0.60
0.0
1.05
0.42
0.75
0,11
0.88
1.16
0.11
0.70
0.12
1.01
0.84
0.2ft
0.14
0.78
2,11
0.21
0.8567582
1.050060
28
^
80
60 1028
581
566
155
188
051
564
782
500
ui
127
12
76
11
58
106
10
36
S8 06
i4 188
S22 64
-------
    FAST-TRACK DATA
                                       PROJECT   enI
                                                        FASTTRACK LOAn PATA

                                                           3ITEIO    06710225
                                                                                                  1611* MONO".  JANUARY  4,  1*82   54
    EVENT
    START
    TIME
PRECIPITATION
(INCHES)
COO
MILLIGRAMS
PER LITER
TSS
MILLIGRAMS
PER L'TFR
PHOSPHORUS
MILLIGRAMS
PER LITER
LEAD
MILLIGRAMS
PER LITER
COPPER
MILLIGRAMS
PER LITER
    05/15/80
    05/17/80
    OT/Ot/tO
    05/03/81
    OS/OJ/81
    05/09/81
    05/12/81
    07/17/81

SITE MEAN
SITE COEFFICIENT OF VARIATION

NUMBER OF EVENTS FOR THIS STATION
0.65
0.39
0.27
0.22
0.38
0.21
0.29
0.59
0.3784279
0.0426575
«2
59
170
300
340
86
68
78
151.2115
0.7671075
                              247
                              197
                              1070
                              256
                              988
                              205
                              135
                              243

                              417.2345
0.51
0.46
1
1.6
0.94
0.4
0.29
0.5
0.7218595
0.6145716
0.179
0.104
0.18
0.46
0.46
0.077
0.066
O.I
0.2079746
0.874869
0.018
0.014
0.05
0.08
0.1
0.02
0.016
0.025
0.04126308
0.8925941
    FAST»TRACX DATA
                                       PROJECT   COI
                                                        FASTTRACK lOAr> TATA

                                                           SITEID    "6710610
                                                                                                  16118 MONDAY, JANUARY 4, 1982   55
    EVENT
    START
    TIME
PRECIPITATION
(INCHES)
    04/23/80                      1,77
    04/30/80                      1.97
    OS/08/80                      0.2S
    OS/15/80                      0.59
    05/16/80                      0.08
    05/17/80                      0.91

SITE MEAN                         i.069648
SITE COEFFICIENT OF VARIATION     0.9J92044

NUMBER OF EVENTS FOR THIS STATION      6
COD
MILLIGRAMS
PER LITER
71
71
66
52
4?
It
56.32011
0.3336561
TSS
"ILLI<'R»MS
PER L'TFR
063
562
190
256
?OA
85
309. 5'T*
0.767V9
PHOSPHORUS
MILLIGRAMS
PER LITER
0.53
0.15
0.085
0.27
0.21
0.14
0.2367029
0.6968631
LEAD
MILLIGRAMS
PER LITER
0.04
0.025
0.15
0.022
0.017
0.008
0.04486426
1.276301
COPPER
MILLIGRAMS
PER LITER
0.018
0,019
0.012
0.012
0.01
0,01
0.01357642
0.2887182
    FAST»TRACK DATA
                                       PROJECT   CHI
                                                        FASTTRACK LOAn P«TA

                                                           SITEIO    "6711585
                                                                                                  16118 MONDAY. JANUARY 4, 1912   5»
    EVENT
    START
    TIME
PRECIPITATION  COD            TSS            PHOSPHORUS     LEAD           COPPER
(INCHES)       MILLIGRAMS     MILLIGRAMS     MILLIGRAMS     MILLIGRAMS     MILLIGRAMS
               PER LITER      PER L'TFR      PER LITER      PER LITER      PER LITER
    05/03/80
    06/14/80
    05/03/81

 SITE MEAN
 SITE COEFFICIENT OF  VARIATION

 NUMBER  OF EVENTS FOB  THIS  STATION
0.31
0.59
0.23
0.3905218
0.510731?
310
162
410
307.0165
0.504716
788
711
232
637.507"
0.7647471
1.2
1.28
2.6
1.739467
0.4495004
0.43
0.406
0.84
0.572228
0.4212895
0.09
0.042
0.13
0.09316719
0.627*217
                                                                    B-3

-------
    FAST-TRACK H«T»
                                       PROJECT   CO!
                                                        FASTTRACK LOAf> ''ATA

                                                           SITEIB    A67H63S
16U8 MONDAY.  JANUARY  a,  t»82    IT
    EVENT
    START
    TIME
    OS/08/80
    OS/11/80
    05/12/80
    05/15/60
    OS/lT/80
    07/20/80
    08/10/80
    09/08/80
    09/10/80
    09/10/80
    01/01/81
    OS/01/81
    OS/05/81
    05/09/81
    OS/16/81
    05/17/81
    OS/28/81
    OS/28/81
    07/02/81

SITE MEAN
SITE COEFFICIENT OF VARIATION

NUMBER OF EVENTS FOR THIS STATION
PRECIPITATION
(INCHES)

0.24
0.07
0.0}
0.52
0.28
0.1}
0.05
0.70
0.08
0.15
0.17
0.22
0,08
0.58
0.10
0.78
0.00
0.22
0.12
0,2020100
1.170906
COO
MILLIGRAMS
PER LITER
115
159
1 60
81
no
300
600
102
170
29}
310
280
0*0
100
200
79
200
160
300
230.9788
0.6181203
TSS
MILLI"R«*S
PER L1TFR
659
358
507
338
032
092
560
210
128
735
380
,
568
215
350
180
508
}92
000
027. 2W
0.50310X8
PHOSPHORUS
MILLIGRAMS
PER LITER
0.69
0.36
0.08
0.14
0.01
1,7
0.8
0.19
0.20
0,79
0.57
0,61
1.8
0.01
0.69
0.1
(1.66
0.51
0.51
0.6022148
O.SS021I
LEAD
MILLIGRAMS
PER LITER
0.22
0.200
0.220
0.10ft
0.24
0.46
0.45
0.116
0.096
0.101
0.05
0.10
0.03
0.17
0.27
0.08
0.26
0.19
0.27
0.266499
11.5420350
COPPER
MILLIGRAMS
PER LITER
0.5
0.01
0.041
0,028
0.01}
0.058
0,058
0.026
0.017
0.002
O.OS
0.16
0.09
0.011
0.06
0.020
0.085
0,055
0.056
0.06877S1I
0.89049
                                       19
    FAST-TRACK DATA
    EVENT
    START
    TIME
    08/10/80
    OS/12/81
    05/28/81
    07/12/81

SITE MEAN
SITE COEFFICIENT OF VARIATION

NUMBER OF EVENTS FOR THIS STATION
FASTTRACK LOAP TATA
PROJECT
PRECIPITATION
(INCHES)
0.69
0.28
0.18
0.62
0.0716985
0.7178299
16H8 MONDAY, JANUARY
C01 SITEIB "6711010
COO
MILLIGRAMS
PER LITER
88
00
ISO
88
100.5621
0.6772068
TSS
MILLIGRAMS
PER L'TFR
90
10
508
148
219.2789
1.712*3'
PHOSPHORUS
MILLIGRAMS
PER LITER
O.o
0.23
0. 65
0.17
0.0221909
0.0453097
LEAD
MILLIGRAMS
PER LITER
0.159
0.019
0.54
0.16
0.2709215
1.073016
COPPER
MILLIGRAMS
PER LITER
0.014
0.008
0.04
0.016
0.02044296
0.7089*9
    FASToTRACK DATA
                                       PROJECT   C01
                                                        FASTTRACK  LOAP  P»TA

                                                           SITEID     06720020
                                                                                                  16H8  MONDAY.  JANUARY  o,  l»82   S9
    EVENT
    START
    TIME
    05/07/80
    07/01/80
    07/02/80
    08/15/80
    08/25/80
    08/26/80

SITE MEAN
SITE COEFFICIENT OF VARIATION

NUMBER OF EVENTS FOR THIS STATION
PRECIPITATION
(INCHES)

0.81
0.19
0.38
0.37
0.20
0.30
0.3931602
0.5281268
COO
MILLIGRAMS
PER LITER
60
17(1
255
100
116
104
136.75S7
0.5267523
TSS
MiLLitoR*Ms
PER L'TFR
158
200
613
123
lit
108
21T.O"2»
0.73S<>6«2
PHOSPHORUS
MILLIGRAMS
PER LITER
0.14
0.6}
0.96
0.71
0.61
0.52
0.6195516
0.1561129
LEAD
MILLIGRAMS
PER LITER
O.Mt
A. 15
0.744
0.26
0.101
1). 19
0.2650751
0.7711025
COPPER
MILLIGRAMS
PER LITER
0.01
0.018
0.040
0.015
0.016
0.02
0.02441411
0.5819626
                                                                   B-4

-------
    FAST-TRACK OATA
                                       PROJECT   COI
                                                        FASTTRACK LOAf f>»T«

                                                           SITEIO    t9*236105042400
                                                                16119 MONDAY,  J*NU«RY 4, 1«82   60
    EVENT
    START
    TIME
PRECIPITATION
(INCHES)
coo
MILLIGRAMS
PEP LITER
TSS
MILLI'-ROMS
PEP. HTFR
PHOSPHORUS
MILLIGRAMS
PER LITER
LEAD
MILLIGRAMS
PER LITER
COPPER
MILLIGRAMS
PER LITER
    OT/OI/80
    OT/ll/80
    07/30/eo
    oa/or/ao
    08/10/80
    08/10/60
    08/25/80
    09/08/80
    09/08/80
    09/10/80

SITE *EiN
SITE COEFFICIENT OF VARIATION

NUMBER OF EVENT* FOR THIS STATION
o.oa
O.IJ
0.06
0.07
0,04
1.99
0.34
0.05
0.72
0.08
0.4019668
2.I619S6
IS7
290
640
9S
470
68
96
440
81
110
212.1817
0.0994623
114
192
184
278
192
155
57
272
28
14
175.5*31
t.326'5!
0.3
0.43
1.3
1.15
0.71
0.22
0.27
0.77
0.19
0.15
0.567877
0.9011743
0.167
0.31
0.5
0.633
0.32
0.16
0.102
0.33
0.049
0.046
0.2890032
1.138593
0.021
0.03
0.075
0.055
0.04S
0.016
0.012
0.05
0.014
0.009
0. 03199(41
0.8417194
                                       10
    FAST-TRACK nATA
                                                        FASTTRACK LOA<> *ATA

                                       PROJECT   OC1       SITEID    ''CISIUROS
                                                                16118 MONDAY.  JANUARY 4, 19M   61
    EVENT
    START
    TIME
PRECIPITATION
(INCHES)
COD
MILLIGRAMS
PFR LITER
TSS
MlLLfR'MS
PER L'TFR
PHOSPHORUS
MILLIGRAMS
PER LITER
LEAD
MILLIGRAMS
PER LITER
COPPER
MILLIGRAMS
PER LITER
    11/04/80
    11/09/80
    11/25/80
    11/29/80
    12/09/80
    12/23/80
    02/20/81
    02/21/81
    02/22/81
    02/22/81
    03/04/81
    03/16/81
    03/30/81
    03/31/81

SITE MEAN
SITE COEFFICIENT OF VARIATION

NUMBER OF EVENTS FOR THIS STATION
,
,
0.63
0.31
0.2
0.13
0.33
0.06
0.15
1.3
0.4S
0.14
0.9R
0.14
0.4155559
1.149514
16
56
12
4
40
32
40
36
46
20
m
31
52
25
34.52076
0.8372978
                              13
                              154
                              8
                              1
                              21
                              6
                              39
                              23

                              17
                              18
                              22
                              102
                              II

                              36.2776
                              0.29
                              0.26
                              0.2
                              O.I
                              0.12
                              0.17

                              0,06
                              1,66
                              0.11
                              0,16
                              0.65
                              0.24
                              0.12

                              0.3043352
                              1.096979
                                       14
    FAST-TRACK DATA
                                       PROJECT   OC1
                                                        FASTTRACK I0«f r>ATA

                                                           SITEIO    nCIStUROS
                                                                16118 MONDAY,  JANUARY  4,  1982   62
    EVENT
    START
    TIME
PRECIPITATION  COO            TSS            PHOSPHORUS     LEAD           COPPER
(INCHES)       MILLIGRAMS     MILLIGRAMS     MILLIGRAMS     MILLIGRAMS     MILLIGRAMS
               PER LITER      PER L'TFR      Pfs LITER      PER LITER      PER  LITER
    09/17/80
    09/25/80
    11/04/80
    11/09/80
    11/16/80
    11/27/80
    12/09/80
    02/02/81
    02/06/81
    02/10/81
    02/19/81
    02/20/61
    02/22/81
    03/04/81
    03/16/61
    03/30/81

SITE MEAN
SITE COEFFICIENT OF VARIATION

NUMBER OF EVENTJ FOH THIS STATION
0.31
•

B
0.9
0.21
0.2
0.84
0.31
0.85
0.49
0.2
1.14
0.59
0.28
0.38
0.5236732
0.6857102
41
36
20
60
60
19
46
56
56
55
52
54
54
t
as
72
49.1793
0.398802
12
6
12
152
9
3
22
44
24
43
20
23
19
6
10
37
27.31947
1.213»5°
0.14
0.27
1.38
0.36
0.24
O.J9
0.23
1.46
1.12
1.1
0.57
0.34
. 0.56
0.38
0.22
0.34
0.578409
0.7225627
                                       16
                                                                   B-5

-------
    FAST.TRACK DATA
                                       PROJECT   OC1
                                                        FASTTRACK LOAP n»TA

                                                                     PCI51UR06
                                                                US 18 MONDAY. JANUARY «,  1*92   »3
    EVENT
    START
    TIME
PRECIPITATION  COD            TSS
(INCHES)       MILLIGRAMS     MILL
               PER LITER      PER
                                             PHOSPHORUS
                                             MILLIGRAMS
                                             PER LITER
                                             LEAD
                                             MILLIGRAMS
                                             PER LITER
                                             COPPER
                                             MILLIGRAMS
                                             PER LITER
    10/2S/80
    It/17/80
    11/24/80
    11/2T/80
    02/02/81
    02/02/81
    02/08/81
    02/11/81
    02/14/81
    02/20/81
    02/22/81
    03/OS/81

SITE "EAN
SITE COEFFICIENT OF VARIATION

NUMBER OF EVENTS FOR THIS STATION
,
1
I.I
0.3
0.85
0.82
0.26
0.9
O.TJ
o.or
o.sa
o.aa
0.7384666
1. 00302*
16
a?
12
10
96

71
62
60
as
50
.
51.15582
0. 8528895
08
61
52
IS
221
10
65
lit
49
31
72
25
67.0SATA

                                                            SITEIO    PC1S1UR07
                                                                                                  16118 MONDAY. JANUARY 4, i««a   »«
     EVENT
     START
     TIME
PRECIPITATION
(INCHES)
COD
MILLIGRAMS
PER LITER
TSS
MILLI»R«»S
PER L'TFB
                                             PHOSPHORUS
                                             MILLIGRAMS
                                             PER LITER
LEAD
MILLIGRAMS
PER LITER
COPPER
MILLIGRAMS
PER LITER
     07/22/80
     07/23/80
     07/29/80
     08/01/80
     08/03/80
     08/00/80
     08/18/80
     08/19/80
     09/10/80
     10/02/80
     10/25/80
     10/28/80
     11/04/80
     11/24/80
     11/27/80

 SITE MEAN
 SITE COEFFICIENT OF  VARIATION

 NUMBER  OF  EVENTS FOR THIS  STATION
0.32
0.11
0.1
0.67
0.21
0.66
0.42
0.17
0.11
0.51
2.25
0.00
0.28
0.78
0.57
0.08*3155
1.341025
36
47
61
•

74
140
33
132
t
10
22
28
60
12
59.11295
0.8101985
207
420
66
116
120
140
825
99
294
230
510
25
16
66
28
203.000"
1. 663*97
0.21
0.26
0.11
0.24
0.27
0.22
0.9«
0.14
0.5
e
0.7
0.08
0.29
0.23
0.12
0.3088217
0.7829968
                                        15
    LFILE  (STORfT)  DATA
                    LFTLE(STORET) LHAP DATA


     PROJECT   220CCITY                 SITEIO
                                                                                                   16U8  MONDAY, JANUARY 4, 1982   12
                                                                                         DC151UR09
    EVENT
    START
    TIME
BOD
MILLIGRAMS
COD
MILLIGRAMS
PER LITER
80116
TSS
MILLI»R«MS
PER L'TfH
530
                                             PHOSPHORUS
                                             MILLIGRAMS
                                             PER LITER
                                             665
LEAD
MILLIGRAMS
PER LITER
COPPER
MILLIGRAMS
PER LITER
1042
     10/02/80
     10/25/80
     11/04/80
     11/17/80
     11/24/80
     It/27/80
     12/09/80
     12/16/80
     12/23/80
     02/02/81
     02/08/81
     02/11/81
     02/19/81
     03/30/81

 SITE MEAN
 SITE COEFFICIENT HF  VARIATION

 NUMBER  OF  EVENTS FIR THIS  STATION
t
3.249999
4
^
•

a
•

10
B
4.2

.
6.134019
0.636327t
92.59999
138
24
20
22.31007
36
60
68
a
48
07
61
52.01957
00
55.5930?
0.574268
1
21
0
0
6
3.5
9
11
72
50
13
13
10.53029
6
16.66C8"
1.176»21
. O.I 0.02
1.349949 0.12 0.02
0.35 0.
0.5599999 0.
0.4380716 0.
0.10 0.
0.09999996 0.
. o.
. o.
0.32 0.
0.3 0.
0.32 0.
0.08978614 0.
O.lt 0.
0.02
0.02
0.02
0.02
0.02
0.02
0,065
0.02
0.02
0.02
0.02
0.02
0.3775807 0.1010313 0.02286345
0.9496051 0.04875641 0.32298T3
                                                                   B-6

-------
    FAST-TRACK nATA
                                       PROJECT   OC1
                                                        FASTTRACK LOAP
                                                           SITEIO
                                                                                                  16118 MONDAY,  JANUARY «, J98Z   65
    EVENT
    3T1PT
    TIME
PRECIPITATION  COO            TSS            PHOSPHORUS     LEAD           COPPER
(INCHES)       MILLIGRAMS     MILLI^R'MS     MILLIGRAMS     MILLIGRAMS     MILLIGRAMS
               PER LITER      PER LITFR      PER LITER      PER LITER      PER LITER
    to/18/80                      .              62             as             0.13
    10/25/80                      .              26             19             0.6
    10/21/80                      .              Sa             42             O.JI
    11/17/80                      1.25           22             18             0.48
    11/24/80                      1.5            8              68             0.44
    12/09/80                      0.2            60             33             .
    02/02/81                      1.21           60             145            1.55
    02/08/81                      0.29           72             49             0.93
    02/19/81                      0.55           80             37             0.65
    02/20/81                      0.37           40             34             0.17
    02/22/81                      0.87           56             21             0.17
    03/16/81                      0.22           18             44

SI7E MEAN                         0.7579506      49.79799       45.96096       0.5715447
SITE COEFFICIENT OF VARIATION     0.9244045      0.7881695      0.629A8M      0.7946728

NUMBER OF EVENT!) FOR THIS STATION      12
    FAST»TRACK nATA
                                       PROJECT   OCI
                                                        FASTTRACK LOAP I»ATA

                                                           SITEIO    I-C15IUP15
                                                                                                   16118  MQNOAr. JANUARY 4,  1981   66
    EVENT
    START
    TIME
PRECIPITATION  COO             TSS             PHOSPHORUS
CINCHES)       MILLIGRAMS      MILLI<>R
-------
    IFILE (STORfT) 04TI
               LFILEfSTORET)


PROJECT   22ILCITV
                                  0»T»


                                   8ITEIO
                                                                                                  16118 MO«IO«T, JANUARY «, 1962   IS
                                                                                         BASINI
    EVENT
    START
    TIME
    01/11/80
    ot/u/eo
    01/07/80
    01/16/80
    01/24/80
    01/28/80
    05/10/80
    04/01/80
    04/08/80
    05/12/80
    05/12/80
    05/16/80
    05/17/80
    05/21/80
    06/01/80
    06/15/80
    06/15/80
    06/21/80
    06/28/80
    07/26/80
    07/27/80

SITE MEAN
SITE COEFFICIENT OF VARIATION

NUMBER OF EVENTS FOR TMI3 STATION
BOO COO
MILLIGRAMS MILLIGRAMS
PER LITER
. 140
287.1818
.
211.2115
477.7659
0
B
^
107.0111
^
219.1068
t
a

,
f
112.2691
216.1258
.
.
616.9002
128.2567
294.4682
0.5602676
TSS
MILLIGRAMS
PER LITFf) I
510
471.6771
aiS.8'74
181.8787
116.6*57
T0.14«OT
145.7061
40.88C2»
221. 7»1?
I02.172*
97.95041
80.77S91
221.275
194.1070
162.841''
95.6268'S
.
,
129.7*5»
116.9'21
e
«
159.177'
0.6111141
'M08PHORUS LEAR
MILLIGRAMS MILLIGRAMS
•ER LITER PER LITER
1051
1.865788
4.166665
1.447552
0.809779
0.1724004
'

{. 097894
B
0.6646952
*


J
B
0.12A8717
0.7885989

^
0.6027911
0.418074
1.145414
0.89*7704
COPPt»
MILLI6RAMS
PER LITER
1042
0.0686842
0.1411111
0.05700216
0,01261464
0.01241249
t

0.01019871
B
0.05672818
.


0

0.01626562
0.01066791
,
.
0.0505901
0.01700577
0,04785276
0.8105187
                                       21
    LFILE (STORFT) 0«T»
               LFILE(STORET) Ln«f B«T»


PROJECT   22!LCtTr                 SITEIB
                                                                                                  16118 «ONO«T. J»»U»RY 4, 1982   1*
    EVENT
    ST»RT
    TIME
    01/11/80
    01/16/80
    01/07/80
    01/16/80
    01/24/80
    01/28/80
    04/01/80
    05/12/80
    05/12/80
    05/17/80
    05/17/80
    05/21/80
    05/10/80
    06/01/80
    06/15/80
    06/15/80
    06/21/80
    06/28/80
SITE
SITE COEFFICIENT L'F ViRIiTION
NUMBER OF EVENTS FOR T«IS STtTION
BOO COD
MILLIGRAMS MILLIGRAMS
PER LITER
140
112.1111
(
116.887
446.0501
(
B
216.6899
200.0104
171.2029
^

B
142.6512
B
118.6606
227.5171
•
222.7416
0.4547546
TSS '
MILLI"R«MS «
PER L'TFR p
510
155.7179
182.V71
208.5714
85,97*40
68.08>2«
112.4K6*
256.7460
70. 2941"
.
100.9«9«
79.1041'
129.0»6«
141.6511
99.0!»2K
,
.
71.5476'
152.670°
0,62!(>5ei
NOSPMOBU8
tLLICRAMS
ER LITER




















                                                                                              »Et Ll*l»
                                                       t. 71^225

                                                       «Is79Z7l»
                                                       ,
                                                       %

                                                       0.*56719I

                                                       J.1185815
                                                       0.5640911
                                                       0.7518844
                                                       0.4041906
                                                                      5.rlll4594

                                                                      »!9429»6«4




                                                                      9.04420955

                                                                      0.12179649
                                                                      0.01880109
                                                                      t
                                                                      *

                                                                      0.03379893
                                       18
                                                                  B-8

-------
                                                                         DATA
                                                                                                  16118 MONDAY. JANUARY *, 1982   IT
    LFILE (STORFT) DATA
                                       PROJECT   22ILCITY
                                                                          SITEIn
                                                                                         HASINA
    EVENT
    START
    TI"E
BOO
MILLIGRAMS
COO
MILLIGRAMS
PER LITER
500
TSS
MILLIfc»"MS
PER HTFR
530
PHOSPHORUS
MILLIGRAMS
PER UITER
LEAD
MILLIGRAMS
PER LITER
COPPER
MILLIGRAMS
PER LITER
1002
    01/16/80
    03/16/80
    os/12/ao
    os/12/eo
    05/17/90
    OS/17/80
    05/19/80
    05/23/80
    05/10/80
    06/01/80
    06/01/80
    06/1S/80
    06/21/80
    06/28/80
    OT/2T/80

SITE «E»N
SITE COEFFICIENT (IF vtRUTION

NUMBER OF EVENT* FOR THIS STATION
                              252. «16'
                0.0«70


               36.31613

               60.10392
               fO.8102
               0.3192808
               89.5739?
               SI.07MO
               5l.3««9«
               a3.29-!57
               S9.38»9?
               a9.82l<0«

               60,a937t
               S1.53J7
               40.85020

               76.98«7*
               0.636»aai
                                                            Q.I893661
                               ,2606739


                              Q.208163

                              Q.137JJ11
                              0.2018036
                              0.3a3H632
                                                                           0.009999947
                               .02(87791


                              0.01320915

                              0.01483731
                              0.01598058
                              0.3956SU
                                       15
    FIST.THICK n>Tt
                                                        FASTTRtCK
                                       PROJECT    IL1
                                                                                                  16118 MONOtT. J»NU»BT «, 1982   »7
    EVFNT
    ST4RT
    TIME
PRECIPITITION  COD             TSS            PHOSPHORUS     LE*0           COPPER
(INCHES)       MILLIGRAMS      MILLIU»»»S     MILLIGRAMS     MILLIGRAMS     MILLIGRAMS
               PER LITER       PER L'TFR      PER LITER      PER LITER      PER LITER
    03/16/80
    Oa/03/80
    06/15/80
    06/23/80
    06/28/80

SITE MEAN
SITE COEFFICIENT (IF VARIATION

NUMBER OF EVENTS FOR THIS STATION
0.56
0,13
0.1
0.9
0.26
O.«32679g
1.182239
30
50
t
. 72
71
57.82062
0.3661807
167
120
119
•

1S7.3»9«
0.186fO*2
0.18
0.29
t
0.512
0.503
0.3858905
0.5332017
0.065
Q.ll
f
0.17
0.13
0.1217139
0.0220929
0.008
0.01
.
0.02
0.02
0.0109611
0.5012609
                                                                    B-9

-------
    LPILE (STORltT) DATA
                    LFILE(STORET)  LPAP DATA


     PROJECT    22ILCITY                 SITEID
                                                                                                  16118 MONBAV, JANUARY 4|  1982   19
                                                                                         BASINS
    EVENT
    START
    TIME
    03/u/ao
    03/16/80
    01/28/80
    01/28/80
    01/10/80
    01/10/80
    04/01/80
    00/05/80
    00/06/80
    01/08/80
    OS/12/80
    OS/12/80
    OS/12/80
    OS/12/80
    05/16/80
    OS/16/«0
    OS/17/80
    OS/1T/80
    OS/10/80
    OS/10/80
    06/01/80
    06/01/80
    06/1S/80
    06/IS/80
    06/IS/80
    06/1S/80
    06/21/80
    06/21/80
    06/28/80
    06/2A/80
    07/26/80
    07/27/80

SITE MFAN
SITE COEFFICIENT OF VARIATION

NUMBER OF EVENTS FIR THIS STATION
ROD
MILLIGRAMS

110

































COO
MILLIGRAMS
PER LITER
140
58.4125
58.4125
o

c
t
42.14572
42.10572
.
.
119.6711
119.671!
182.9102
182.9102
.
t
110.0102
110.0102
201,1527
201.1527





72.92587
72.92587
119.5901
119.5901
.
•
100.868!
0.7012707
TSS
MILLIGRAMS
PER L'TFR
510
78.1254*
78.12*4!
106.1140
106.1100
85.00007
85.00007
200. 7*96
200.7*96
115,718*
115.718*
iii.r»73
111 ,8*7*
70.2808
70.2808
258,9?8»
25«.9?*o
86,84*97
86.84*97
I6S.SOOJ
165,5003
116, 4*1^
117, 4»7?
117.4»7?
101. 5?!*
101. 5?1*
.

.
.
219.7*9*
82.66<>5
110.1101
0.!97'7«2
PHOSPHORUS
MILLIGRAMS
PER LITER
665
0.2590686
0.2590686
f
^
^

0.4022798
0.4022748
t
f
1.625831
t. 625831
0.8018U9
0.8018149
m
t -
o,57u|S69
0.57fl|569
1.551721
1.551721
'
t
.
e
B
0.5421657
0.5421657
1.195111
1.19511!
.
.
0.8909148
0.7066708
LEAD
MILLIGRAMS
PER LITER
1051
0,1914925
0.. 1914925


*

0.1801088
Q. 1801088

B
0.5007062
0.5007062
0,4140929
0.4140929
4

0.2810106
0.2810106
0.2605287
0,. 2605287





0.1069285
0.10692*5
0.1701512
0.1701512
^
•
0.2690612
0.0009I9I
COPPER
MILLIGRAMS
PER LITER
1042
0.0192807
0.019280?


|

0.02805741
0.028057(1
.
.
0.06555597
0,06555597
0.05617112
0.05617112
.
.
0.04141267
0.04141267
0.00702009
0.00702009





0.05955511
0.05955511
0.09888159
0.09888159
,
•
0.05281804
0.5252925
                                       12
    FAST-TRACK rtATl
                                       PROJECT   IL2
                                                        FASTTRACK LHAr r«TA

                                                           3ITEIB    C
                                                                                                  16H8 MONDAY, JANUARY o, 1982   68
    EVENT
    START
    TIME
PRECIPITATION  COO            TSS            PHOSPHORUS     LEAD           COPPER
(INCHES)       MILLIGRAMS     MILLI»I)«MS     MILLIGRAMS     MILLIGRAMS     MILLIGRAMS
               PER LITER      PER L'TFR      PER LITER      PER LITER      PER LITER
    00/01/80
    05/17/80
    05/28/80
    07/09/80
    07/20/80
    08/00/80
    08/19/80
    09/22/80

SITE MEAN
SITE COEFFICIENT OF VARIATION

NUMBER OF EVENTS FOR THIS STATION
0.25
0.17
0.91
0.2!
1. 11
0,19
0.68
0.52
0.599663
0.6*1986]
170
.
280
190
64
66
5!
,
143.6384
0.7942812
                              142
                              171
                              861

                              in
                              92
                              81
                              128

                              292.7To«
0.044
0.027
0.759
0.187
0.228
0.29
0.228
                                             0.1981965
                                             0.4481118
0.598
2.41
0.768
0.261
0..16

5.107
               0.7990195
               t.655541
0,052
0.052
0.108
0.049
0.011
0.028
0.026
               0.04984587
               0.5281887
                                                                 B-10

-------
    FAST-TRACK n>TI
                                       PROJECT   MA|
                                                        FASTTRACK LOAP PATA

                                                           SIHIO    P|
                                                                16118 MONDAY.  JANUARY  1,  1962   69
    EVENT
    START
    TIME
PRECIPITATION
(INCHES)
COO
MILLIGRAMS
PER LITER
TSS
MILLIGRAMS
PER L'TFR
PHOSPHORUS
MILLIGRAMS
PER LITER
LEAD
MILLIGRAMS
PER LITER
COPPER
MILLIGRAMS
PER LITER
    06/29/80
    07/08/80
    OT/1T/80
    OT/29/80
    08/02/80
    08/01/80
    09/10/80
    09/18/80

SITE MEAN
SITE COEFFICIENT OF VARIATION

NUMBER OF EVENTS FOR THIS STATION
2.U
o.ai
0.38
t.ei
o.t
0.11
0.12
0.76
0.8340111
1. 600796
ISO
an
85
62
60
26
too
96
81.20623
0.5736233
32
57
122
ft
26
02
39
320
85.69»1«
1.516?"
0.2
0.23
1.58
0.56
0,15
0.52
0.15
0.08
0.1896191
0.9716267
0.117
0.217
0.29
0.12
0.15
0.13
0.13
0.2
0.1699015
0.3103169
0.071
0.061
0.079
0.05
0.056
0.079
O.I
0.09
0.07353801
0.2119718
    FAST»TRACK DATA
                                       PROJECT   Mil
                                                        F»STTR»CK LOAP PATA

                                                           SITE1B    *2
                                                                16H8  MONDAY.  JANUARY 1,  t9«2   70
    EVENT
    START
    TIME
PRECIPITATION  COO            TSS            PHOSPHORUS     LEAD          COPPER
(INCHES)       MILLIGRAMS     MILLIGRAMS     MILLIGRAMS     MILLIGRAMS     MILLIGRAMS
               PER LITER      PER L'TFR      PER LITER      PER  LITER      PER LITER
    OT/IT/80
    07/29/80
    08/02/80
    08/03/80
    08/ll/BO
    09/10/80
    09/18/80
    11/28/80
    12/03/80

SITE MEAN
SITE COEFFICIENT OF VARIATION

NUMBER OF EVENTS FOR THIS STATION
0.38
1.81
0.1
0.13
0.11
0.12
0.76
1.51
0.16
0.6032991
1.715011
101
t
7»
33
67
ITS
150
.
«
106.6815
0.675132!
600
118
80
231
18
110
790
•
•
351. i»3*
2. 052«o;>
1.28
f
0.57
0.5
0.26
1.68
1.59
1.056937
0.8718956
0.33
0.1
0.07
0.35
0.15
0.69
0..7T
0.1391921
1.02221
0.11
0.12
0.01
0.11
0,08
0.13
0.17
0.1117818
0.0899871
    FAST.THICK nATA
                                       PROJECT   MAI
                                                        FASTTRACK LOAP PATA

                                                           SITEIO    P3
                                                                                                  I6HB  MONDAY.  JANUARY  i,  1982   71
    EVENT
    START
    TIME
PRECIPITATION  COD            TSS            PHOSPHORUS     LEAD           COPPER
(INCHES)       MILLIGRAMS     MILLIGRAMS     MILLIGRAMS     MILLIGRAMS     MILLIGRAMS
               PFR LITER      PER L1TFR      PER LITER      PER LITER      PER  LITER
    07/17/80                      0.38           95             735            1,6            0.35           0,1
    08/02/80                      0.1            61             69             0.18           A.19           0.11
    08/11/80                      0.11           66             17             0.38           0.16           0.085
    09/10/80                      0.12           109            78             1.1            0.13           0.1
    09/18/80                      0.76           201            HI            2.3            0.63           0.16
    09/26/80                      0.31           81             53             1.1            0..15           0.086
    11/28/80                      1.51           ....'.

SITE MEAN                         0.5081091      103.8298       257.0T7«i       1.227995       0.2711789       0.1071279
SITE COEFFICIENT OF VARIATION     1.123653       0.1186623      1,706011       0.7850122      0.6720729       0.2319082

NUMBER OF EVENTS FOR THIS STATION      7
                                                                 B-ll

-------
    FUST.THICK n*T»
                                       PROJECT   Mil
                                                        FASTTRACK LOAn f>ATA

                                                           SITEIO    ft
                                                                16116 MONDAY.  JANUARY  a,  1482    71
    EVENT
    START
    TIME
PRECIPITATION
(INCHES)
COO
MILLIGRAMS
PER LITER
TSS
MILLIGRAMS
PER L1TFR
PHOSPHORUS
MILLIGRAMS
PER LITER
LEtO
MILLIGRAMS
PER LITER
COPPER
MILLIGRAMS
PER LITER
    06/16/80
    06/24/80
    OT/1T/80
    08/02/80
    08/01/80
    08/11/80
    04/10/80
    04/18/80

SITE «E»N
SITE COEFFICIENT Of VARIATION

NUMBER OF EVENTS FOR THIS STATION
0.2
2.10
0.38
0.1
0.13
0.11
0.12
0.76
0,0743688
1.504644
162
42
100
47
.
05
62
100
84.50644
0.4484723
168
07
320
SB
106
12
10
500
t45,l*3«
2.310?T«
0.56
0.66
1.61
0.2
•
0.1
0.31
0.8
0.671104
1.170516
•
0.3
0.42
Q.040
.
0.020
0. US
0
0.2381244
t. 540778
.
0.08
0.17
0.064
•
0.024
0.048
0.04
0.07306094
0.7074341
    FAST.TRACK OATA
    EVENT
    START
    TIME
FASTTRACK LOAP fATA
PROJECT
PRECIPITATION
(INCMES)
MAI
COD
MILLIGRAMS
PER LITER
SITEID T5
TSS
MILLIGRAMS
PER L'TFR

PHOSPHORUS
MILLIGRAMS
PER LITER
                                                                                                  16U8 MONDAY,  JANUARY  o,  1482   73
                                                            LEAD           COPPER
                                                            MILLIGRAMS     MILLIGRAMS
                                                            PER LITER      PER  LITER
    06/20/80
    06/24/80
    07/08/80
    07/17/80
    07/24/80
    08/02/80
    08/03/80
    OD/li/80

SITE MEAN
SITE COEFFICIENT OF VARIATION

NUMBER OF EVENTS FOR THIS STATION
0.20
2.10
0.41
0.38
1.81
0.1
0.13
0.11
0.7046204
1.788182
06
148
54
08
77
115
25
05
71.74562
0.6186321
14
21
74
122
02
17
56
0
53.1T>6?
l.080'6t
0.07
0.13
0.25
1.41
0.56
0.03
0.020
0.026
0.368114
3.001112
;
0.20
0.20
0.38
0.23
0.06
0.072
0.05T
0.1464674
0.4382051
.
0.15
0,06
0.15
0.13
0.1
0,058
0.075
0,1008203
0.0322257
    FAST-TRACK nATA
                                       PROJECT   MAI
                                                        FASTTRACK LOAr> PATA

                                                           SITEID    "6
                                                                                                  16MB MONDAY. JANUARY  o,  1482    7*
    EVENT
    START
    TIME
PRECIPITATION  COO            TSS            PHOSPHORUS
(INCHES)       MILLIGRAMS     MILLIGRAMS     MILLIGRAMS
               PER LITER      PER L'TFH      PER LITER
                                             LEAR           COPPER
                                             MILLIGRAMS     MILLIGRAMS
                                             PER LITER      PER LITER
    04/10/80                      0.12           118            33             0.78           0.33           0.08
    04/18/60                      0.76           44             244            0.75           0.34           0.05
    11/28/80                      1.54           22             6              0.052          ,
    12/03/80                      0.16           15             3              I).036          .              0.017
    12/10/80                      0.04           15             1              0.024          .              0.004

SITE MEAN                         0.723747?      60.17362       U2.5*2"       0,5172345      0.3612547      0.05531311
SITE COEFFICIENT OF VARIATION     2.768308       1.360481       10.3674?    .   4.144468       0.1185383      2.205485

NUMBER OF EVENTS FDR THIS STATION      5
                                                                 B-12

-------
    FAST-TRACK nATA
                                       PROJECT   MI J
                                                        FASTTRACK 101* "ATA

                                                           3ITEIO    PITAASETBNNINLT
                                                                16118 MONDAY, JANUARY a, 1982
    EVENT
    START
    TIME
    06/30/79
    10/22/79
    08/10/80
    08/10/80
    04/09/80
    09/09/80
    09/17/80
    09/17/80
    10/24/80
    10/20/80
    02/17/81

SITE ME/IN
SITE COEFFICIENT OF V»HI«T!ON

NUMBER OF EVENTS FOB THIS STATION
PRECIPITATION
(INCHES)

2.25
0.25
0.4
0.4
0.9
0.9
0.67
0.67
0.45
0.45
•
0.7297964
0.6727471
COO
MILLIGRAMS
PER LITER

,
42
4?
t
t
13
33
51
51
42
42.10252
0.1795844
TSS
MILLlbR'M9
PER LITFR
136
70
48
47
65
65
40
44
41
at
90
62.7252*
0.39554H7
PHOSPHORUS
MILLIGRAMS
PER LITER
0.26
0.5
0.16
0,16
0.19
0.19
0.16
0.16
0.33
0.33
0.23
0.2428575
0.3985752
LEAD
MILLIGRAMS
PER LITER
0.11
0.07
0.041
Q.OO
f
0.04
0.033
0.02
0,047
0.05
.'
0.05054435 I
0.5018807 I
EOPPER
MILLIGRAMS
»ER LITER
1.01
).02









.01594706
.521092
    FAST-TRACK DATA
                                       PROJECT   "13
                                                        FASTTRACK LOA* r>4TA

                                                           SITEIO    PITAARETBNSINLT
                                                                                                  16118 "ONOAY. JANUARY 4,  19(2    76
    EVENT
    START
    TIME
    06/30/79
    10/22/79
    OB/10/90
    08/10/60
    09/09/80
    09/09/80
    09/17/80
    09/17/80
    10/24/ftO
    10/24/80
    02/17/81

SITE MEAN
SITE COEFFICIENT nF VARIATION

NUMBER OF EVENTS FnR THIS STATION
PRECIPITATION COO
CINCHES) MILLIGRAMS
PER LITER
2.25
0.25
o.a
O.a
0,9
0.9
0.67
0.67
0.45
0.45
•
0.7297964
0.6727471
m
2*
2B
12
12
27
27
26
26
51
30.77205
0.2153033
TSS
MILLIGRAMS
PER L'TFR
52
22
40
ao
47
47
41
41
68
68
102
S1.98?6»
0,a08"0<»2
PHOSPHORUS
MILLIGRAMS
PER LITER
0.13
0.04
0.07
0.07
1.13
O.II
0.12
0.12
0.11
0.12
0.32
0.1247865
0.5541494
LEAD COPPER
MILLIGRAMS MILLIGRAMS
PER LITER PER LITE*
0.01 0.005
0.003 0.001
0.001
0.01
0.009
0.09
0.006
0.005
0.011
q.oi
.








0.01488687 0.004272911
1.634308 1.62835
                                       11
    FAST-TRACK nATA
                                       PROJECT-  Ml 3
                                                        FASTTRACK LOAP PATA

                                                           3ITEID    »» METLANOS INT
                                                                                                  16118 MONDAY. JANUARY 4, 1982   77
    EVENT
    START
    TIME
PRECIPITATION  COD            TSS            PHOSPHORUS     LEAD           COPPER
(INCHES)       MILLIGRAMS     MILLIORAMS     MILLIGRAMS     MILLIGRAMS     MILLIGRAMS
               PER LITER      PER L»TFR      PER LITER      PER LITER      PER LITER
    08/20/80
    08/20/80
    02/17/81
    04/11/81
    04/13/81
    04/22/81
    05/29/81

SITE MEAN
SITE COEFFICIENT (IF VARIATION

NUMBER OF EVENTj FOR THIS STATION
1.75
1.75
B
1.1
0,89
0.95
0.59
1.191277
0.4400687
37
^
42
28
26
13
26
32.09648
0.2011566
69
69
84
82
139
55
17
78.6570*
0.723'«5?7
0,17
0.17
f
0.14
0.18
0.1
0.05
0.1401844
0.5266365
0.012
0.02
a
0.01
0.012
0.006
•
0.01224952
0.4534759
                                                                 B-13

-------
    FAST-TRACK f»T>
                                       PROJECT   Mil
                                                        r«STTR«CK LOAP PATA

                                                           SITEID    TR»v CK »f BN I
                                                                16118 MONDAY. JANUARY «, 19M   TS
    EVENT
    START
    TIMt
PRECIPITATION
(INCHES)
COO
MILLIGRAMS
PER LITER
TSS
MILLIGRAMS
PER L'TFR
PHOSPHORUS
MILLIGRAMS
PER LITER
LEAD
MILLIGRAMS
PER LITER
COPPER
MILLIGRAMS
PER LITER
    01/11/81
    01/11/81
    01/22/81
    05/09/81
    Ok/13/81

SITE MEAN
SITE COEFFICIENT OF VARIATION

NUMBER OF EVENTS FOR THIS STATION
1.1
1
0.95
1.1
I.S
1.191721
0.2057117
26
18
21
28
29
21.41058
0.191692
14
12
19
9
22
11.15*79
0.706?119
0,08
0.12
0.09
0.06
0.1
0.090682H
0.2616188
0.001
0.001
0.002
0.001
0.002
0.001118119
0.1917521
    FAST»TRACK DATA
                                       PROJECT   Mil
                                                        FASTTRACK LOAP "ATA

                                                           SITEIO    'O?
                                                                16H8 MONDAY. JANUARY i,  I«M    7*
    EVENT
    START
    TIME
PRECIPITATION  COO            TSS            PHOSPHORUS
(INCHES)       MILLIGRAMS     MILLIGRAMS     MILLIGRAMS
               PEP LITER      PER L'TFR      PER LITER
                                             LEAD           COPPER
                                             MILLIGRAMS     MILLIGRAMS
                                             PER LITER      PER LITER
    05/10/80
    06/01/80
    06/05/80
    07/05/80
    07/16/80
    08/02/80
    08/10/80
    10/21/80

SITE MEAN
SITE COEFFICIENT OF VARIATION

NUMBER OF EVENTS FOR THIS STATION
0.28
0.01
0.5
0.92
0.96
0.19
0.51
0.11
0.5591517
0.1101557
92
61
61
92
70
66
55
.
72.02281
0.196101
170
12
76
210
91
16
82
11
98.51«2«
0.891'«116
0.75 (
0.21 (
0.11 (
1.1
0.67
0.21
0.56
0.12
0,5171021 (
0.6119997 1
.25
.027
.11





.1705958 I
.596619 (
1.071
1.021






.05519105
.8918196
    FAST-TRACK [>ATA
                                       PROJECT   MM
                                                        FASTTRACK LOAP PATA

                                                           SITEIO    CO*
                                                                                                  16H8  MONDAY. JANUARY i, 1982   80
    EVENT
    START
    TIME
PRECIPITATION  COO            TSS
(INCHES)       MILLIGRAMS     MILLIGRAMS
               PER LITER      PER L'TFB
    01/01/80
    01/21/80
    05/10/80
    06/01/80
    06/05/80
    07/05/80
    07/16/80
    08/02/80
    08/10/80
    09/09/80
    09/22/80
    10/11/80
    10/16/80
    10/17/80
    10/21/80

SITE MEAN
SITE COEFFICIENT OF VARIATION

NUMBER OF EVENTS FOR THIS STATION
0.61
0.28
0.28
0.11
0.61
0.92
0.96
0.19
0.51
0.22
0.19
0.11
0.11
0.11
0.11
0.0933909
0.1196616
7T
81
150
16
89
09
17
61
19
.
0
t
6
51
49
70.11519
0.8971175
                              110
                              16
                              220
                              19
                              51
                              100
                              97
                              29
                              60
                              70
                              6
                              71
                              9
                              12
                              II

                              70.77?1»
PHOSPHORUS LEAD COPPER
MILLIGRAMS MILLIGRAMS MILLIGRAMS
PER LITER PER LITER PER LITER
0.19 0.21 0
0.11 0.056 0
0.17 0.11 0
0,1 0.02 0
0,1 n.ii o
0,27
0.01
0.1?
0.15
0.26
0.12
0.2
0.08
(







0.11 0.065 0
0.25 0.016 0
0.1918971 0.1501599 0
1.051611 1
.156115 0
.016
.015
.01
.008
.012
.016







.051
.008
.01997651
.7196151
                                       IS
                                                                 B-14

-------
    F»ST-TR»CK n«T«
                                       PROJECT   Mil
                                                        F»STTR»C«

                                                           SITEIO
                                                                     CO"
                                                                16118 MQNO»Y.  JANUARY a,  198Z   SI
    EVENT
    ST»RT
    TIME
PRECIPIT4TION  COD            TJS            PHOSPHORUS     LE«0           COPPER
(INCHES)       MU.UGRIMS     MILLI»R«MS     MILLIGRtHS     MILLIGRAMS     MILLIGRAMS
               PER LITER      PER L'TFR      PER LITER      PER LITER      PER LITER
    00/03/80
    Ok/01/80
    07/16/80
    OS/02/80
    08/10/80
    09/22/80
    10/U/80
    10/17/80
    10/21/80

SITE MEtN
SITE COEFFICIENT OF V4HMTIOM

NUMBER OF EVENTS FOR THIS ST»TION
0.63
0.03
0.96
0.39
0.53
O.a9
o.oo
0.05
0.03
0.5350051
0.28S7929
56
02
od
07
40
75
t
60
»7
S«. 03805
0.2308596
330
110
230
03
210
68
ISO
130
60
153. S'S*
0.763»0
-------
    FAST-TRACK OATA
                                       PROJECT   301
                                                        FA9TTRACK LOAP PATA

                                                           3ITEIO    06«16300
                                                                16119 MONO**. JANUARY 4, 1*82   84
    EVENT
    START
    TIME
PRECIPITATION
(INCHES)
COD
MILLIGRAMS
PEP LITER
TSS
"ILLItaR«MS
P£» L'TFR
PHOSPHORUS
MILLIGRAMS
PER LITER
LEAO
MILLIGRAMS
PER LITER
COPPER
MILLIGRAMS
PER LITER
    06/10/80
    07/12/60
    07/20/80
    07/2S/80
    08/20/80
    10/15/60

SITE MEAN
SITE COEFFICIENT OF VARIATION

NUMBER OF EVENT!! FDR THIS STATION
301
303
127
127
165
92
196.4154
0.5605369
10700
6120
1760
645
3700
1120
4578. »2S
1.450*4?
6.42
2.86
1.16
0.49
l.»3
0.72
2.434644
1.196099
2
0.46
0.21
0.23
0.28
0.13
0.5415241
1.224
    FAST-TRACK DATA
                                       PROJECT   TX1
                                                        FASTTRACK LOAf* "ATA

                                                           SITEIB    "APT LANE
                                                                                                  16118 MONDAY, JANUARY 4, 1982   90
    EVENT
    START
    TI«E
PRECIPITATION
(INCHES)
COD
MILLIGRAMS
PER LITER
TSS
MULIbR»MS
PER L»TFH
PHOSPHORUS
MILLIGRAMS
PER LITER
LEAD
MILLIGRAMS
PER LITER
COPPER
MILLIGRAMS
PER LITER
    02/04/81
    02/10/81
    03/03/81
    03/07/81
    03/07/81
    03/12/81
    03/12/81
    03/29/81
    04/17/81
    05/02/81
    OS/16/81
    05/23/81
    05/23/81
    06/01/81
    06/02/81
    06/03/81
    0*/30/al
    09/14/81
    09/15/81

SITE MEAN
SITE COEFFICIENT OF VARIATION

NUMBER OF EVENTS FOR THIS STATION
0.28
0.33
0.35
0.33
0.34
0.34
0.2
0.47
0.4
fl.94
.
0.04
0,25
0.36
0.19

*
0.3674517
0.7777799
16
137
34
34
53

96
210
29
63
82
»
34
97
4*
B
B
.
73.167J8
0.8116161
42
201
43
43
17
•
316
334
21
153
272
•
84
183
34
9
228
42
14S.S«6«
1.6SO?9?
^
0.24
0,192
0.19
0.112

0.882
0.995
0.253
0.31
0.445
0.145
0.327
0.168
0.09
0.35
0.25
0.3283534
0.7552314
                                       19
    FAST»TRACK DATA
                                       PROJECT   TX1
                                                        FASTTRACK LOAr DATA

                                                           SITE10    "OILINGMOOD
                                                                                                  16118 "ONOAT. JANUARY 4, 1982   9|
    EVENT
    START
    TIME
PRECIPITATION  COD            TSS            PHOSPHORUS     LEAD           COPPER
(INCHES)       MILLIGRAMS     MH.LIUR>MS     MILLIGRAMS     MILLIGRAMS     MILLIGRAMS
               PER LITER      PER L1TFR      PER LITER      PER LITER      PER LITER
    04/17/91
    05/16/81
    05/23/81
    06/01/81
    06/02/81
    06/05/81
    06/25/81
    07/05/81
    08/07/81

SITE MEAN
SITE COEFFICIENT OF VARIATION

NUMBER OF EVENT* FOR THIS STATION
0.49
1.25
1.1
0.19
0.46
0.35
1.45
1.95
0.45
0.8995625
0.90«1327
102
S3
133
59
36
39
104
57
145
85.999B2
0.5439013
a
,
.
19T
371
37
165
180
131
19810B9?
0.88924C7
>
t
,
0.267
0.168
0.144
0.245
0.34
0.168
0.2239391
0.3426537
                                                                 B-16

-------
    FAST.TBAC"  nATA
                                      PROJECT   NA1
                                                       FASTTRACK LOAr r»T»

                                                          SITEID    ?0»»ELL0566
                                                                                                 16116 MONDAY. JANUARY a, 1962   92
    EVENT
    START
    TIME
PRECIPITATION  COD            T3J            PHOSPHORUS      LEAD           COPPER
(INCHES)       MILLIGRAMS     MILLIGRAMS     MILLIGRAMS      MILLIGRAMS      MILLIGRAMS
               PER LITER      PER L'TFR      PER LITER       PER  LITER       PER  LITIR
    00/10/80
    00/18/80
    OS/21/60
    05/20/80
    05/27/80
    06/01/60
    06/OS/60
    06/16/60
    06/20/60
    06/25/80
    07/11/80
    07/1U/80
    OS/26/80
    06/27/60
    09/01/60
    04/06/80
    04/12/80
    04/11/80
    04/20/80
    04/29/80
    04/29/60
    10/08/80
    10/12/80
    10/21/80
    10/11/60
    11/01/80
    11/01/80
    11/08/60
    11/10/80
    11/19/80
    11/20/80
    11/25/80
    11/27/60
    11/28/60
    12/02/80
    12/OJ/60
    12/00/80
    12/ta/eo
    12/20/60
    12/21/80
    12/20/60
    12/20/60
    12/26/60
    12/29/80
    01/17/81
    01/23/81
    01/26/81
    01/28/81
0.15
I.I!
0.14
0.64
0.04
0.14
0.18
0.2
0.72
0.08
0.28
0.10
0.00
O.OJ
0.57
0.21
0.12
0.16
0.25
0.14
0.04
0.11
0.16
0.17
0.70
0.56
0.51
0.0|
0.15
0.19
1.55
0.22
0.7
0.63
0.69
0.12
0,00
0.17
0.28
0.00
0.26
0.07
0.32
0.72
0.15
0.08
0.16
0.6
67
13
08
16
31
76
26
110
01
57
09
03
85
75
30
07
3?
J4
80
30
22
78
22
80
01
63
35
36
83
38
32
22
26
23
30
28
27
77
36
33
OS
55
23
22
05
57
20
13
87
61
114
66
92
222
59
259
95
110
85
137
80
140
SO
60
20
156
149
2680
102
168
27
138
106
188
85
68
125
042
42
72
83
66
78
66
62
152
104
113
120
91
68
60
102
161
81
69
0.27
0.1A7
0.368
0.15
0.116
0.023
0.1
0.56
0.275
0.256
0.257
0.172
0.57
3.61
0.076
0.271
0.149
0.1
0.3*3
0.306
0.39
0.256
0.202
0.375
0.212
0.303
0.155
0.135
0.17
0.92
0.29}
0.52
0.151
0.126
0.201
0.049
0.123
0.307
0.236
0.211
0.221
0.101
0.120
0.103
0.51
0.283
0.272
0.087
0.53
O.I
0.16
0.15
0.12
0.06
0.12
1.02
0.14
0.16
0.21
0.2
8.14
0.53
0.1
0.26
0.1
0.1
0.185
0.78
0.24
0.26
0.1
0.29
0.16
0.11
0.1
0.1
0.15
0.25
0.1
0.15
fl.l
O.I
(1.1
0.2
0.1
0.3
0.2
0.1
0.2
0.1
0.1
0.1
0.2
0.3
0.1'
0.1
    FA3T»TRACK  DATA
                                       PROJECT    HA1
                                                        FASTTRACK  LDAn  r>»TA

                                                           SITFID     7006ELLOS86
                                                                                                  16U8 MONDAY. JANUARY a,  i»82   41
    EVENT
    START
    TIME
    02/11/61
    02/11/61
    02/11/61
    02/10/61
    02/17/81
    02/18/81
    02/14/61
    03/20/81
    03/24/61
    00/05/81
    00/06/81
    00/07/61
    00/10/61
    00/12/61
    00/20/61
    00/22/61
    00/23/61
    00/27/61
    05/07/61
    05/11/81
    05/10/61
    05/10/81

SITE MEAN
SITE COEFFICIENT OF VARIATION

NUMBER OF EVENTS FOR THIS STATION
PRECIPITATION
(INCHES)

I
0.20
0.22
0.78
0.16
0.55
0.03
0.21
o.la
0.18
0.30
0.26
0.36
0.12
0.19
0.2S
0.07
0.53
0.21
0.36
0.18
0.08
0.3453"!
1.006670
COO
MILLIGRAMS
PER LITER
01
27
71
66
11
58
19
32
39
02
02
27
32
29
50
16
36
55
03
67
62
70
00.1662
0.0960426
TSS
MILLIGRAMS
PER L'TFR
90
66
too
242
70
2625
105
71
66
67
115
02
117
157
78
76
01
80
121
219
161
190
|OS,l»9t
0.872'1"1
PHOSPHORUS
MILLIGRAMS
PER LITER
0.218
0.130
0.171
0.069
0.146
0.359
0.136
0.163
0.115
0.27S
0.088
0.105
0.226
0.51
0.21
0.16
0.117
0.254
0.261
0.256
0.221
0.366
0.2806S22
0.6660403
LEAD COPPER
MILLIGRAMS MILLIGRAMS
PER LITER PER LITE*
0.117
0.
0.
0.
0.
0.
0.
0.
0.
0.
0 •
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.



5

















0.2060086
0.6505185























      70
                                                                  B-17

-------
    FAST»TRACK  DATA
                                       PROJECT   *AI
                      FASTTR1CK

                         SITEIO
                                                                       BATA

                                                                     ?0»8ELL0588
                                                                                                  16111 MONDAY,  JANUARY  «,  1962   «l
    EVENT
    START
    TIME
PRECIPITATION  COO            TSS            PHOSPHORUS     LE»0           COMER
(INCHES)       MILLIGRAMS     M1LLI"I>»MS     MILLIGRAMS     MILLIGRAMS     MILLIGRAMS
               PER LITER      PER LUFR      PER LITER      «R LITER      PER LITER
    03/12/80
    01/26/60
    00/05/80
    oa/os/eo
    04/09/80
    00/10/80
    00/18/80
    07/11/80
    07/10/80
    08/26/80
    08/27/80
    08/28/60
    04/01/80
    09/06/80
    04/12/80
    09/11/60
    09/19/60
    09/20/80
    09/29/80
    10/08/80
    10/20/80
    10/11/60
    11/01/60
    11/03/80
    11/06/80
    11/06/60
    11/U/80
    11/19/80
    11/20/80
    11/35/80
    11/27/80
    11/28/60
    12/02/80
    12/01/80
    12/10/80
    12/20/80
    12/20/60
    12/20/80
    12/25/80
    12/26/80
    12/29/60
    01/17/81
    01/28/81
    02/11/61
    02/11/81
    02/11/81
    02/17/61
    02/18/81
0.1]
0.57
0.2
0.18
1.19
0.22
0.15
0.08
0.16
0.17
0.5
0.27
O.OR
0.10
0.09
0,16
0.01
0.19
0.16
0.70
0.29
0.6
1.18
0.01
0.12
0.21
1.66
0.15
0.71
0.86
0.97
0.06
0.11
0.01
0.26
0.51
1.28
0.14
1.10
0.22
0.61
0.91
0.2
0.1
0.16
0.71
21
79
50
18
00
69
IT
126
102
15
29
07
JO
0!
56
76
02
19
10?
51
06
12
51
15
50
Ot
10
11
29
50
02
26
69
58
62
20
27
20
19
07
20
52
10
60
0]
10
70
210
112
108
40
196
41
142
127
106
266
144
56
90
72
90
62
166
115
174
140
57
100
95
91
64
250
71
60
29
49
51
68
71
100
95
98
60
76
81
41
125
66
80
62
104
90
154
0.11
0.11
0.25
0,26 .
0.19
0.54
0.097
0.29
0.149
0.95
LIT
0.091
0.121
0.105
0.11
0.117
0.207
0.157
0.177
0.16
0.206
0.109
0.18
0.155
0.081
0.142
0.227
0,165
0.15
0,261
0.112
0.101
0.17
0.061
0.219
0.178
0.161
0.084
0.114
0.21
0.092
0.17
0.005
0.161
0.21!
0.227
0.07
0.254
O.I
0.15
0.27
0.2
0.2
0.11
0.1
0.21
0.1
0.51
0.49
0.2
0.1
0.22
O.I
0.1
0.1
0.24
0.116
0.25
0.15
0.09
0.14
0.06
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
A.
0.2
0
0
0
0.
0
0
0
0.2
O.I
0.2
    FAST-TRACK DATA
                                       PBOJECT
                                                        FA8TTRACK LOAr PATA

                                                 Kit       SITEIO    ?0*BELL0588
                                                                                                  16118 MONDAY, JANUARY 4. 1962   95
    EVENT
    START
    TIME
    02/19/81
    01/24/81
    01/28/81
    04/02/81
    04/05/81
    04/06/81
    04/07/81
    04/10/81
    04/12/81
    04/22/61
    04/27/81
    05/01/81
    05/07/81
    05/07/81
    05/10/81

SITE MEAN
SITE COEFFICIENT OF VACATION

NUMBER OF EVENTS FOR THIS STATION
PRECIPITATION
(INCHES)

0.02
0.26
0.18
0.16
0.16
0.18
0.22
0.1
0.1!
0.08
0.07
0.21
0.16
0.11
0.29
0.0156407
1.001046
COD
MILLIGRAMS
PFB LITER
12
72
11
100
OS
05
21
27
06
06
11
95
82
61
00
06.87826
0.5212600
TSS
MILL1"R«MS
PER L1TFB
116
76
62
191
56
147
04
67
117
128
72
104
116
166
87
100.9011
0.07110"
PHOSPHORUS
MILLIGRAMS
PER LITER
0.046
0.22
0,122
0.505
0.172
0.545
0.068
0.2
0.255
0.145
0.186
0.291
0.108
0.1S7
0.202
0.2196841
0.879827!
LEAD
MILLIGRAMS
PER LITER
0.1
0.1
0.1
0.2
O.I
0.2
0.1
O.I
0.2
O.I-
0.2
O.I
0.2
0.2
0.1
0.1544166
0.4612612
COPPER
MILLIGRAMS
>ER LITER

















                                                                 B-18

-------
    FAST-TRACK o»T4
                                       PROJECT    Wit
                                                        FASTTRACK  LOAP  "ATA

                                                           SITEIO
                                                                1*118  MONf)A»,  JANUARY 4.
                                                                                                                                 f6
    EVENT
    ST»BT
    TI«E
PRECIPITATION
(INCHES)
COO
MILLIGRAMS
PER LITER
TSS
MILLIGRAMS
PER L»TFR
PHOSPHORUS
MILLIGRAMS
PER LITER
LEAD
MILLIGRAMS
PER LITER
                                                                          COPPER
                                                                          MILLIGRAMS
                                                                          PER LITER
    05/28/80
    09/09/80
    09/22/80
    09/22/80
    OS/21/81
    05/29/81
    06/08/81
    06/11/81
    06/20/81
    08/26/81
    08/29/81

SITE MEIN
SITE COEFFICIENT OF VARIATION

NUMBER OF EVENTS FOR THIS STATION
0.86
1.2a
0.58
0.24
O.OS
0.27
0.27
O.S8
0.18
.

O.S360208
1.2J5IT
9
160
7!
46
ISO
ISO
130
110
92
120
120
119.1616
0.4044821
194
72
82
92
479
272
144
SI
157
202
70
166. 8CS"
0.762*SM
0.11
0.1
0,14
0.16
0.72
0.18
0.64
0.16
0.97
0.29
0.14
0.1728127
0.8917225
0.4
0.15
0.15
0.2
0.9S
0.46
0.6
O.I
O.S
0.4
0.2
0.1857911
0.7966797
    FAST.TRACK DATA
                                       PROJECT   Mil
                                                        FASTTRACK  LOAP  PATA

                                                           STTEID     «l*63l
                                                                16118  MONDAY.  JANUARY 4,  1982   9T
    EVENT
    START
    TIME
PRECIPITATION  COD            TSS            PHOSPHORUS
CINCHES)       MILLIGRAMS     MILLI>>R'MS     MILLIGRAMS
               PER LITER      PER LUFR      PER LITER
LEAD           COPPER
MILLIGRAMS     MILLIGRAMS
PER LITER      PER LITER
    01/15/80
    04/01/80
    04/04/80
    04/06/110
    04/09/80
    OS/11/80
    05/18/80
    05/28/80
    06/01/80
    06/02/80
    06/05/80
    06/06/80
    06/07/80
    06/19/80
    07/05/80
    07/09/80
    07/15/80
    07/16/80
    07/25/80
    08/02/80
    08/02/80
    08/04/80
    08/07/80
    08/07/80
    08/11/80
    08/16/80
    02/22/81
    04/08/81
    04/13/81
    04/23/81
    05/29/81
    06/08/81
    06/13/81
    06/15/81
    06/20/81
    07/12/81
    07/17/81
    07/20/81
    08/14/81
    08/15/81
    08/26/81
    08/29/81
    08/31/81
    09/07/81

SITE MEAN
SITE COEFFICIENT OF VARIATION
•

m
f
t
B
0.21
0.3
t
t
B
t
t
0.21
0,71
0.72
0.28
0.55
0.18
0.19
0.17
1.20
0,">7
0.17
0.05
0.73
0.05
1.08
1.42
f
0.27
0.3
0.59
0.11
0.16
0.71
0.18







0.5617392
1,297878
81
81
150
71
140
45
250
55
230
78
92
78
80
76
73
120
92
110
74
11(1
140
55
76
43
64
130
170
63
63
63
46
180
180
76
82
82
170
170
92
92
83
83
61
27
99.50628
0.4954272
98
132
44
210
38
472
90
512
38
161
270
438
348
158
438
206
188
14|
64
244
72
246
180
58
68
45
112
280
34?
82
186
336
56
21
390
290
143
442
49
283
120
236
61
4U
JO?, 001"
1.020?2«
0.28
0,28
0.12
0.1
0.09.
0.8
0.15
0.79
0.16
0.22
0.17
0,17
0.41
0.26
0.44
0.27
0,29
0.2
0.17
0.19
. 0.14
0.29
0.2
0,12
0.14
0.16
0.26
0.18
0.43
0.18
0.38
0.49
0.15
0.14
0.6
O.SI
0.25
0.34
0.14
0.29
0.18
0.24
0.12
0.1
0.2913495
0.5767536
0.3
0.6
0.2
0.6
0.16
2
0.35
2.4
0.19
0.49
0.67
1.2
1.5
0.47
0.95
0.46
0.61
0.52
0.22
0.58
0.215
1.6
0.45
0.2
0.1
0.33
0.3
O.SI
1
0.3
0.16
0.9
0.2
O.I
1.2
0.9
0.35
0.6
n.2
0.6
0.3
0.6
0.2
0.05
0.6064536
0.9409928
                                                                 B-19

-------
    FAST-TRACK nATA
                                                        FASTTRACK LOAP PATA
                                       PROJECT   »tl
                                                                                                  16118 MONDAY, JANUARY «, 1962   *•
    EVENT
    STAPT
    TIME
PRECIPITATION  COO            TSS            PHOSPHORUS     LEAD           COPPER
(INCHES)       MILLIGRAMS     MILLIONS     MILLIGRAMS     MILLIGRAMS     MILLIGRAMS
               PER LITER      PER L'TFR      PER LITER      PER LITER      PER LITER
NUMBER OF EVENTS FOR THIS STATION
    PAST-TRACK DATA
                                       PROJECT   KII
                                                        FASTTRACK LOAP PATA

                                                           StTEIO
                                                                I6iie HONDAV. JANUARY «,  198Z   ««
    EVENT
    START
    TIME
PRECIPITATION  COD            TSS            PHOSPHORUS     LEAD           COPPER
(INCHES)       MILLIGRAMS     MlLLIbR«MS     MILLIGRAMS     MILLIGRAMS     MILLIGRAMS
               PF.R LITER      PER L'TFR      PER LITER      PER LITER      PER LITER
    06/02/80                      .              ?6             02             0.1S           0.11
    06/06/80                      0.67           55             44             0.24           0.14
    06/07/80                      0.6            16             27             0.28           0.025
    06/28/80                      0.44           4t             21             0.14           0.08S
    09/12/80                      0.95           18             18             0.1*           O.OS
    09/16/80                      O.S5           ?S             28             0.15           0.1
    09/20/80                      0.7S           22             27             0.24           O.OS
    09/25/80                      0.15           27             60             0.22           0.05
    05/10/81                      0.67           16             49             0.27           0.05
    05/24/81                      0.05           55             96             0.34           0.1
    05/29/81                      0.08           55             140            0.48           0.24
    06/08/81                      0.1J           160            394            0.88           0.5
    06/13/81                      0.53           160            28             0,15           0.05
    06/15/81                      .              27             72             0.23           0.1
    06/20/81                      0.26           32             32             0.13           0.095

SITE MEAN                         0.5460049      48.96661       66.3664        0.270388       0.1133655
SITE COEFFICIENT OF VARIATION     1.264S19       0.7861794      0.974*7^6      0.5399149      0.843580!

NUMBER OF EVENT* FOR THIS STATION      15
                                                                 B-20

-------
    FAST-TRACK DATA
                                       PROJECT   Mil
                                                        F»STTR»CK  LOAH  PATA

                                                           SITEIO     "H611
                                                                161 IS  MONDAY.  JANUARY «,  I9SZ   100
    EVENT
    START
    TIME
PRECIPITATION
(INCHES)
COD
MILLIGRAMS
PER LITER
TSS
MILLIGRAMS
PER L'TFR
PHOSPHORUS
MILLIGRAMS
PER LITER
LEAD
MILLIGRAMS
PER LITER
COPPER
MILLIGRAMS
PER LITER
    06/06/80
    06/07/80
    06/28/80
    or/os/so
    07/09/80
    07/16/80
    08/02/80
    08/04/80
    08/07/80
    08/07/80
    08/11/80
    09/16/80
    09/20/80
    09/25/80
    10/05/80
    11/29/80
    12/06/80
    12/08/80
    02/22/81
    00/00/61
    04/08/81
    00/10/81
    04/11/81
    04/21/81
    05/10/81
    06/08/81
    06/08/81
    06/11/81
    06/22/81
    07/12/81
    07/12/81
    OT/U/81
    07/18/81
    07/20/81
    07/25/81
    OR/07/81
    08/10/01
    08/15/81
    08/28/81
    08/29/81
    08/31/81
    09/07/81

SITE ME»N
SITE COEFFICIENT OF VARIATION

NUMBER OF EVENTS FOR THIS STATION
0.71
0.65
0.48
0.94
•
•
0.25
•
1.2
0.07
0.85
0.81
0.67
0.13
t
.
0.59
0.27
0.76
0.74
0.74
t.2
0.52
•
0.59
0.11
0.14
0.5





0.41
O.J8
0.11






0.60)5121
0.882(1422
32
58
52 .
19
39
39
28
28
56
26
26
26
24
14
40
40
34
55
20
20
67
67
67
17
17
24
56
56
54
54
70
70
2
2
11
11
11
31
33
13
13
33
42.17976
0.8528U13
216
106
31
111
41
75
144
144
6
8
57
59
76
79
60
2
126
19
SI
116
106
118
65
56
11
61
172
32
58
158
94
110
311
86
57
270
119
158
14
57
41
124
114.6«0?
1.4467)7
0.12
0.34
0.17
0.25
0.16.
0.17
0,34
0.31
0.16
0.16
0.27
0,2
0.26
0.22
0.29
0,12
0.74
0,11
0.1
0.44
0.19
0.3
0.16
0.16
0.14
0.27
0.58
0.21
0.18
0.32
0.22
0.2
0.18
0.2
0.17
0.18
0.26
0.22
0.09
0.14
0.16
0.21
0.2491974
0.4461515
0.1!
0.06
0.1
0.09
o.oa
0,06
0.22
0.17 f
0.05
0.05
0.12
0.05
0.125
0.1
0.1
0.05
0.22
0.05
0.05
0.25
0.05
0.05
0.05
0.05
0.05
O.t
0.26
0.1
0.12
0.25
0.1
0.05
0.22
0.05
O.I
0.1
0.2
O.I
0.05
1.1
0.05
0.05
0.1126706
0.6908119
                                       42
    FAST»TRACK DATA
                                       PROJECT   nil
                                                        FASTTRACK LOAO TATA

                                                           SITEIO    417614
                                                                                                  I6H8  MONDAY.  JANUARY  4,  1982   101
    EVENT
    START
    TIME
PRECIPITATION  COO            T3S            PHOSPHORUS     LEAD           COPPER
(INCHES)       MILLIGRAMS     MILLIGRAMS     MILLIGRAMS     MILLIGRAMS     MILLIGRAMS
               PER LITER      PER HTFR      PER LITER      PER LITER      PER  LITER
    06/05/80
    06/28/80
    09/16/80
    09/20/80
    09/22/80
    09/22/80
    09/25/80
    10/01/80
    05/10/81
    05/21/81
    05/29/81
    05/29/81
    06/08/81
    06/15/81
    06/20/81
    08/26/81
    08/27/81
    08/29/81
    08/11/81

SITE MEAN
SITE COEFFICIENT OF VARIATION

NUMBER OF EVENTS FOR THIS STATION
t
^
0.55
0.75
0.18
0.77
0.08

0.56

0.12
0.14
0.18
0.1
0.2

B
B
.
0.1412121
1.007451
16
19
51
29
21
14
14
52
65
65
65
97
120
120
96
98
98
27
27
62.6142
0.6004044
144
12
17
14
1
46
22
12
5
142
212
122
48
71
20
12
11
to
100
67.4519
2.145?0«
0.14
0.17
0.06
0.05
0.67
0.07
0.09
0.1
0.05
0.52
0.41
0.16
O.U
0.17
0.06
0.06
0.01
0,01
0.17
0.1680618
1.111142
0.11
0.1
0.12
0.05
0.05
O.I
0.05
1.05
0.05
0.45
0.51
0.12
0.2
0.2
O.I
0.1
0.05
0.05
0.2
0.149011
0.9148115
                                       19
                                                                 B-21

-------
    FAST-TRACK DATA
                                       PROJtCT   Mil
                                                        FASTTRACX LOAf f«ATA

                                                           SITEIO    "15635
                                                                1611* MONDAY. JANUARY «, 1*62  102
    EVENT
    START
    TIME
PRECIPITATION  COO            TSS            PHOSPHORUS     LEAD           COPPER
CINCHES)       MILLIGRAMS     MILLIGRAMS     MILLIGRAMS     MILLIGRAMS     MILLIGRAMS
               PER LITER      PER L'TFR      PER LITER      PER LITER      PER LITER
    04/03/80
    04/06/80
    00/08/80
    04/09/60
    oa/ia/eo
    04/26/eo
    04/28/80
    05/13/80
    05/18/80
    06/01/80
    06/02/80
    06/05/60
    06/06/80
    06/OT/80
    06/19/80
    07/16/80
    08/02/80
    08/02/80
    08/00/80
    08/11/80
    08/11/80
    08/10/80
    09/07/80
    01/09/80
    09/12/80
    09/16/80
    09/20/80
    09/2S/80
    10/01/80
    10/16/80
    10/16/80
    10/21/80
    11/10/80
    11/20/80
    12/02/80
    12/06/80
    02/16/81
    02/22/81
    00/00/81
    00/07/81
    00/08/81
    00/10/81
    00/10/81
    00/13/81
    OS/29/81
    05/29/81
    06/20/81
    07/12/81
0.08

0.52
0.57

0.23
0.as
0.21
0.13

0.25
0.89
0.72
0.53
0.26
0.24
2.79
0.57
0.05
0.58
0.4
1.26
1.37
0.77
0.72
0.09

0.24
0.29
0.2
0.55
0.60


1.28

0.32
1.21
0.16
0.22
0.21
1.21
60
18
81
100
27
45
65
30
30
35
73
69
58
40
39
140
140
140
too
65
28
28
28
28
28
03
35
30
09
49
50
50
76
76
54
54
98
114
69
160
160
160
160
160
22
120
110
110
14
SI
278
15
53
06
20
240
27
53
63
192
129
90
58
25
162
06
100
27
20
30
9
75
26
25
60
28
08
6
17
29
18
8
72
68
108
70
564
109
199
198
I9»
13R
160
104
07
108
0.04
0.12
0.2
0.0<
0.06
0.11
0.06
0.31
0.07
0,13
0.12
0.16
0,14
0.11
0.14
0.09
0.2
0.08
0.14
0.11
0.5
0.05
0.07
0.06
0.08
0.06
0.07
0.06
0.15
0,05
0.06
0,13
0.06
0.1
0.14
0.12
11.16
0.1
0.38
0.14
0.11
o.ie
0.14
0.06
0.23
0.12
0.07
0.34
0.85
0.32
0.5
0.1
0.22
0.6
0.1
0.75
O.I
0.19
0.22
0.35
A.22
0.22
0.23
0.1
0.335
0.14
0.26
0.075
0.19
0.1
0.05
0.175
0.05
0.15
0.13
0.1
0.2
0.05
O.I
0.15
0.12
0.12
0.5
0.4
0.5
1.4
0.9
0.24
0.26
0.24
0.24
0.12
0.32
0.2"!
0.16
0.25
    FAST-TRACK OATA
                                       PROJECT   Nil
                                                        FASTTRACK LOA" "ATA

                                                           SITEIO    0|i63S
                                                                                                  t6ii8 MONDAY. JANUARY 4,  19»2  10J
    EVENT
    START
    Tine
PRECIPITATION
(INCHES)
cno
MILLIGRAMS
PER LITER
TSS
MILL
PER L'TFR
PHOSPHORUS
MILLIGRAMS
PER LITER
LEAD
MILLIGRAMS
PER LITER
COPPER
MILLIGRAMS
PER LITER
    07/12/81
    07/13/81
    07/18/81
    07/20/81
    08/10/81
    08/15/81
    08/26/61
    08/27/81
    08/29/81
    08/31/81
    09/07/81

SITE MEAN
SITE COEFFICIENT OF VARIATION

NUMBER OF EVfNTs FPR THIS STATION
0.64
3.56

0.27







0.658003
1.182169
100
100
17
17
63
65
65
65
42
42
26
71.12706
0.7010690
ion
40
130
60
81
137
43
25
42
45
23
87.70>»5?
1. 200*57
0.1
0.05
0.13
0.1
0,12
0.12
0.06
0.06
0.08
0.08
0.06
0.1191022
O.S698431
0.15
0.05
0.2
0.15
0.2
0.2
0.05
0.1
0.2
0.05
0.05
0.2212952
0.8279833
                                       59
                                                                  B-22

-------
    FAST-TRACK  DATA
                                      PROJECT   mi
                                                       FASTTRACX LOAC fATA

                                                          SITEIO
                                                               161 IB MONDAY.  JANUARY 4,  1*62  104
    EVENT
    START
    TINE
PRECIPITATION
(INCHES)
COO
MILLIGRAMS
PER LITER
TS9
MILLIGRAMS
PER L'TFD
PN08PMORU8
MILLIGRAMS
PER LITER
LEAD
MILLIGRAMS
PER LITER
COPPER
MILLIGRAMS
PER LITER
    00/00/81
    00/07/91
    04/08/81
    o4/io/8i
    00/11/41
    04/23/st
    05/10/81
    aS/24/81
    05/29/81
    06/08/81
    06/08/81
    06/11/81
    06/20/81
    OT/12/81
    07/12/81
    07/13/81
    07/18/81
    07/20/81
    On/10/81
    08/1S/81
    08/29/81
    08/31/81
    09/07/81

SITE MEAN
SITE COEFFICIENT OF  VARIATION

NUMBER OF EVENTS FOR THIS  STATION
0.61
0.2
0.86
B
1.29

0.77
B
,
0.13
0.16
0.55
0.19
,
m
2.)t
0.52
0.1
f
•

t
•
0.6809089
1.087556
10
240
200
72
72
60
60
78
490
580
580
580
54
54
120
120
53
82
16
J»
48
48
45
156.2122
1.246966
1152
97?
208
242
162
100
26
692
106
18
602
52
98
25S
205
118
221
1!
167
2J9
33
128
30
280.3156
1.562»2?
1.28
1.02
0.31
0.82
0.2
0.9
0.6
2.9
1.2
0.46
2.S
0.4
0.33
0.68
0.44
0.25
0.44
0.22
0.5
0.34
0.19
0.3
0.18
0.6989971
0.9162922
I.I
0.96
O.I*
0.32
0.18
0.15
0.05
0.78
0.42
0.1
0.75
O.I
0.2
0.5
0.35
0.3
0.35
0.15
1.7
0.3
O.I
0.2
0.05
0.4158159
1.205293
                                      23
    FAST.TRACK DATA
                                                       FASTTRACK LOAI" r>»TA

                                       PROJECT    wtt       SITEIO    »U»37
                                                                                                 I6H8 MONDAY, JANUARY 4, 198«  105
    EVENT
    START
    TIME
PRECIPITATION  COD            T33            PHOSPHORUS
(INCHES)       MILLIGRAMS     MH.L!bRAMS      MILLIGRAMS
               PER LITER      PER L1TFR       PER LITER
                                             LEAD           COPPER
                                             MILLIGRAMS     MILLIGRAMS
                                             PER LITER      PER LITER
    06/08/81
    06/08/81
    06/13/81
    06/15/81
    06/20/81
    08/26/81
    08/27/81
    08/29/81
    08/31/81

SITE MEAN
SITE COEFFICIENT OF VARIATION

NUMBER OF EVENTS F(1R THIS STATION
0.11
0.17
0.52
0,09
0.19

t
u
.
0.2211429
0.767188
31
31
31
74
31
31
31
19
19
33.08437
O.OA85739
12
280
16
12
48
21
8
12
10
37.9t«7<»
1.56177
0.16
1.06
0.18
0.12
0.2
0.12
0,06
0.08
0.1
0.2129575
0.987036
0.05
0.46
0.05
0.05
0.1
0.05
0.05
0.05
0.05
0.09133647
0.8642529
 TOTAL NUMBER OF EVENTS
                                       755
                                                          B-23/B-24  blank

-------
        APPENDIX C



DATA ANALYSIS METHODOLOGIES
          C-l

-------
                                 APPENDIX C
                         DATA ANALYSIS METHODOLOGIES
     In order to assemble and analyze the data being developed by the NURP
projects and determine and interpret results, it was necessary for NURP to
use a set of consistent analytical methodologies.  By and large, the metho-
dologies that were selected were developed under different EPA efforts, many
under the sponsorship of the Office of Research and Development.  Following
the areas of project emphasis, Appendix C-l presents for urban runoff loads,
C-2 for receiving water impacts, and C-3 for effectiveness of controls, the
adopted methodologies and their supporting logic.

                          C-l.  URBAN RUNOFF LOADS

     The constituents found in urban runoff are highly variable, both during
an event, as well as from event to event at a given site and from site to
site within a given city and across the country.  This is the natural result
of high variations in rainfall intensity and occurrence, geographic features
that affect runoff quantity and quality, and so on.  Therefore, a method of
expressing the size of an urban runoff load and its variability was needed.
The event mean concentration, defined as the total constituent mass discharge
divided by the total runoff volume, was chosen as the primary statistic for
this purpose, and event mean concentrations were calculated for each event at
each site in the accessible data base.   If a flow-weighted composite sample
was taken, its concentration was used to represent the event mean concentra-
tion.   On the other hand, if sequential discrete samples were taken over the
hydrograph, the event mean concentration was determined by calculating the
area under the loadograph (the curve of concentration times discharge rate
over time) and dividing it by the area under the hydrograph (the curve of
runoff volume over time).  For the purpose of determining event mean concen-
trations, rainfall events were defined to be separate precipitation events
when there was an intervening time period of at least six hours without rain.
Given this data base of Event Mean Concentrations (EMCs), there are a number
of questions that must be answered in order to extract information that will
be useful for water quality planning purposes, including: What is the underly-
ing population distribution and what are the appropriate measure of its attri-
butes, e.g., central tendency, variability, etc.?  Do distinct subpopulations
exist and what are their characteristics?  Are there significant differences
in data sets grouped according to locations around the county (geographic
zones), land use, season, rainfall amount, etc.?  How may these variations be
recognized?  What is the most appropriate manner in which to extrapolate the
existing data base to locations for which there are no measurements?

     These questions have not all been answered as of this preliminary report.
This appendix will outline the procedures used to analyze the problem to date
and projected future work during the remainder of the project.   There will
be no attempt to explain standard statistical procedures since these are
                                   C-2

-------
readily available in the literature.   Nor will the operation of the SAS com-
puter statistical routines be explained since they are available almost uni-
versally at computer centers.  However, the relevant procedures used by the
NURP team will be described.

LOG-NORMALITY

     When working with highly variable data, it is very important to know, at
a prescribed confidence level, what the underlying probability distribution is
(as opposed to assuming or guessing).   Based upon natural  expectations and
prior experience, it was decided to test whether or not the event mean con-
centration data had a log-normal distribution for each water quality con-
stituent to be examined.  The event mean concentration data from all NURP
projects' loading sites were collected into one data set and transformed into
natural logarithm space.  Four separate procedures were used to judge log-
normality and to indicate that the data, in fact, will fit a log-normal
distribution.  They are:

     1.  Inspection of basic statistical measures
     2.  Inspection of graphical data displays
     3.  Kolomogorov-Smirnov test
     4.  Chi-square test

The first two procedures are qualitative in nature and rely upon experienced
professional judgement.  For inspection of basic statistical measures, one
transforms the data into the logarithmic domain and examines the calculated
values of mean, median, mode, kurtosis, etc. with what would be expected from
a normal (Gaussian) distribution.  Graphical data displays used include
cumulative probability distribution plots, stem-leaf plots, box plots,
hanging-root plots, and the like.  Examples of cumulative probability dis-
tribution in log space were given in Chapter 5.  Examples of stem-leaf, box
and hanging root plots are given in Figure C-l.

     The latter two tests are quantitative in nature and were run at the
95 percent confidence level (i.e., a = 0.05).  The Kolmorogov-Smirnov test
is based upon the maximum deviation of the test data from the expected dis-
tribution, while the Chi-square test is based upon the cumulative deviation
of the actual test data distribution from that of the expected distribution.

     The importance of the log-normal  determination cannot be overemphasized.
Among its many implications is the fact that determinations made in simple
arithmetic space with Gaussian assumptions will be invalid, the geometric
mean of the data is a more appropriate measure of central  tendency than the
arithmetic mean, etc.  (Aitchison and Brown, 1969).  With regard to the lat-
ter, it is fairly standard practice to use the geometric mean when dealing
with bacterial data (e.g., coliforms); it has not been so universally applied
to other types of water quality constituents to date.
                                   C-3

-------
-p-
STEM AND LEAF
* »
• *
t
, * * * *
• *
, * * A
.*****
•

• *
•




*
* *
* ft


*
4 *
9 BOXPLOT
2 0
6 0
4
11
5
g
21
10
26
27 + - -





22
17
4
5
6
2






1
— ~ *
1
1







1 0
1 0
1 0
                     ....t-..-f_.-.f....«.-.-t-
                     « MAY REPRESENT UP TO 2 COUNTS
                          (a)   Stem-Leaf  and Box Plots
                                                                                   02   04   .06   08   1.0   102  104
                                                                                                                 HANGING ROOT PLOT
                                                                                        (b)   Hanging Root  Plot
                                      Figure  C-l.   Steam and Leaf,  Box, and  Hanging  Root Plots

-------
DETECTION OF SUB-POPULATION DIFFERENCES

     Although a data set may strongly exhibit a log-normal  distribution, it
still may be made up of a number of sub-populations, and identification of
those might help to explain some of the variance present in the data.   The
key question to be answered is:   Do different log-normal populations (i.e.,
different mean and/or variance)  exist within the pooled population, and if
so, how may homogeneous sub-populations be determined (e.g., how may the
data be grouped into subsets)?  Even if they are log-normal, sub-populations
of data may differ because of; (1) differing means,  (2) differing variances,
or (3) both, as suggested in Figure C-2.   For each parameter, the NURP data
set consists of up to 100 sites  ("treatments" in statistic  parlance) with a
varying number of observations (storms),  on the order of 5  - 20, at each
site.  Even with the considerable advantage of normality of the logarithms
of the EMC's, the general question of how to test the hypothesis of
homogeneity of sample means and  variances is unresolved in  statistics.   The
procedure used for this draft report is outlined below, along with proposed
future analysis.
            xb

            X,.
                                      0.5
                              F(x) = Prob (XSx)
        Figure C-2.  Populations a and b have different variances.
       Populations b and c have different means.  Populations a and c
       differ in both mean and variance.
                                   C-5

-------
     The standard procedure for testing of homogeneity of sample means is
analysis of variance (ANOVA) and its resulting F-test.  Three basic assump-
tions are inherent in the ANOVA procedure:

     1.   Each sub-population (treatment) is normally distributed,
     2.   Each sub-population (treatment) has the same variance, and
     3.   All samples are independent.

Strictly speaking, the assumptions refer to the error term in the ANOVA
model, but they are commonly applied to the data themselves.   The NURP data
generally fulfill assumptions (1) and (3) quite well, but assumption (2),
equality of variances, is not necessarily true.  In fact, it is one of the
conditions upon which to test the hypothesis of homogeneity of population
distributions.

     Fortunately, ANOVA is not highly sensitive to deviations from assump-
tions (1) and (2) as long as the sample size is "relatively large" and the
number of samples in each sub-population is "approximately the same".   These
conditions are met in a quantitative sense for most comparisons, although un-
equal sample sizes are a problem for some, notably sub-populations based on
land use.  However, the fact of insensitivity is the basic justification for
ANOVA procedures used for this preliminary report.   Fortunately, there is no
question of the validity of independence of EMC values since they are all de-
rived from independent storm events.   (Violation of the assumption of indepen-
dence may result in serious errors in inference of the results.)  A discussion
of the ANOVA assumptions and their consequences may be found in many standard
statistics books, e.g., Hays (1981).

     The assumption of homogeneous variance is the most troublesome of the
three since there undoubtedly are sub-populations with differing variances.
Indeed,  the Bartlett test was run on several variables (logarithms of EMC's)
using the DISCRIM procedure of SAS.   The hypothesis of equal  variances was
rejected at a significance level of 0.0001.  However, because of the robust-
ness of the ANOVA procedure, it is seldom recommended that it not be per-
formed just on the basis of the Bartlett or similar tests (e.g., Hays, 1981;
Lindman, 1974).   Rather, the unequal  variances may be accounted for by a
change in the apparent significance level of the F-test.   For instance,
Scheffe (1959)  illustrates this effect when an ANOVA is  performed at an
apparent level  of significance of 0.05.   For different ratios of sample
variance and differing sample sizes,  actual significance  levels may range
from 0.025 - 0.17 (Table 10.4.2 in Scheffe).  Hence, an adjustment in the
assumed level of significance from 0.05 to, say, 0.10 would cover most situ-
ations.   The NURP data rarely exhibit ratios of variances greater than 2:1
and ratios of sample sizes greater than 3:1.

     In other words, there are several  reasons to expect  that the classical
robustness of the ANOVA procedure will  accomodate the NURP data set.   How-
ever, there are other theoretical options, albeit,  inconvenient.

     When sub-populations (treatments)  are compared pair-wise, an inference
may be attempted on the equality of means, given that their variances are
unequal.   This is known in the statistics literature as the Behrens-Fisher
                                   C-6

-------
problem (Winer, 1971) for which a completely satisfactory sampling distribu-
tion is not yet agreed upon.  A common approach is to compute an approximate
t-statistic whose degrees of freedom are obtained by the Satterthwaite approx-
imation technique.  This can be done in SAS using the TTEST procedure.  Un-
fortunately, for a pairwise comparison of all combinations of, say, 100 sites,

(  o  ) = 4950 separate runs would need to be made, infeasible as of this first

report.  In order to achieve a significance level of 5 percent for the entire
family of 4950 tests, Bonferroni (Neter and Wasserman, 1974) specifies that
the significance level, a , of each test should be determined as

«  = 0.05 -r 4050 = 0.000010101.  Clearly, a disadvantage of this procedure is

that the individual tests become so conservative that any differences that
actually exist would frequently fail to be detected.   A variation on this
procedure may be possible in the future if sub-groupings of fewer than all the
individual sites can be determined satisfactorily.

SUB-GROUPINGS

     To date, sub-groupings of site data have been made a priori on the basis
of fundamental hydrologic and water quality considerations.   These attributes
have been:  geographical location or zone, land use,  season, and magnitude
of rainfall event.  At least two questions will be addressed in this sub-
section:  (1) Can groupings be proposed on another basis, and (2) how can
these sub-groups themselves be grouped into similar sub-populations.

     Concerning the former question, it is a legitimate part of an experi-
mental design to group "treatments" into like categories on a rational,
physical basis.  In part, for this first report, this was the only option
available, and reflects conventional engineering wisdom.  Previous studies
have shown differences on the basis of region and land use.   The NURP efforts
to date are the first to investigate the effect, on a large scale, of season
and storm magnitude.

     In the future, it will be useful to perform a grouping in an "unbiased"
manner, in which preconceived notions of groupings may be avoided.  These
groupings may then be compared with those enumerated above to see if they
agree with physical reasoning.  One method for this is cluster analysis, in
which sub-groups with similar attributes (e.g., mean and variance) may be
grouped together into "clusters".  These clusters may be examined for similar
physical attributes (e.g., region, land use) and a regular ANOVA performed
to detect differences in means.  Additional future work will include regres-
sion and correlation procedures utilizing the NURP fixed-site data base for
additional physical insight into cause and effect relationship among EMC's
and independent variables.  Ultimately, selection of the appropriate log-
normal distribution for a study area can be done on a causative basis,
rather than a priori on purely statistical groupings.

     Once again, there is not statistical consensus on a method for selecting
groups of sub-populations when their variances as well as their means may
differ.  However, several procedures are available for multiple comparisons
of means, usually under the assumption of equal variances.  These are de-
scribed, for instance, by Winer (1971) and Chew (1977).  The most common pro-
cedure is that of Duncan, in which means are ranked and placed into one or


                                   C-7

-------
more groups with other means.  The Duncan test (available on SAS) is among
the more discriminating multiple comparisons procedures in terms of finding
differences (Winer, 1971).  That is, compared to certain other available tests,
it will tend to provide more separate groupings.   Because of its wide accep-
tance and because it can be modified to handle unequal sample sizes, it has
been used to date for grouping of subpopulations.  In the future, alternative
procedures may also be used for comparison.

REFERENCES

Aitchison, J.  and J. A.  C. Brown, The Log-Normal  Distribution, Cambridge at
the University Press, 1969.

Chew, V., "Comparisons Among Treatment Means in an Analysis of Variance",
Publication ARS/H/6, USDA, Hyattsville, MD,  1977.

Hays, W. L.,  Statistics, Third Edition, Hold, Rinehart and Winston, 1981.

Lindman, H.  R., Analysis of Variance in Complex Experimental Design,
W. H. Freeman,  1974.

Neter, J. and W.  Wasserman, Applied Linear Statistical Models,
Richard D. Irwin, Inc.,  1974.

Scheffe, H.  A., The Analysis of Variance, Wiley,  1959.

Winer, B. J.,  Statistical Principles in Experimental  Design, Second Edition,
McGraw Hill,  1971.
                                   C-8

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                        C-2.   RECEIVING WATER IMPACTS

     This section presents a description of the methods used to evaluate the
receiving water quality impacts of urban runoff.   Because of the important
differences in behavior, separate methods have been adopted for rivers and
streams and for lakes.   It is anticipated that a technique for evaluating
estuaries as a third class of receiving waters will be developed.   However,
this preliminary NURP report does not include the estuary analysis methods.

RIVERS AND STREAMS

     The approach adopted to quantify the water quality effects of urban run-
off for rivers and streams focuses on the inherent variability of the runoff
process.  What occurs during an individual storm event is considered secon-
dary to the overall effect of a continuous spectrum of storms from very small
to very large.  Of basic concern is the probability of occurrence of water
quality effects of some relevant magnitude.

     Urban runoff is characterized by relatively short duration events with
relatively large time periods between events.  On a national average basis,
the median rainstorm duration is about 4.5 hours with a time between storm
midpoints of about 60 hours.   In addition to this temporal intermittance,
urban runoff events are highly variable in magnitude.

     To consider the intermittent and variable nature of urban runoff, a
stochastic approach was adopted.  The method involves a direct calculation of
receiving water quality statistics using the statistical properties of the
urban runoff quality and other relevant variables.  The approach uses a rela-
tively simple model of the physical behavior of the stream or river (as com-
pared to many of the deterministic simulation models).  The results are
therefore approximations.

     The theoretical basis of the technique is quite powerful as it permits
the stochastic nature of runoff process to be explicitly considered.  (Simu-
lation is in many cases costly or cumbersome in this regard.)  Application is
relatively straightforward, and the procedure is relevant to a wide variety
of cases.  These attributes are particularly advantageous given the national
scope of the NURP Project.  The details of the stochastic method are pre-
sented below.

Basic Approach

     Figure 1 contains an idealized representation of urban runoff discharges
entering a stream.  The discharges usually enter the stream at several loca-
tions but can be aggregated into an equivalent discharge flow which enters
the system at a single point.  The equivalent discharge flow (QR) is the sum
of the individual discharges, and the equivalent concentration (CR) is the
slow-weighted mean concentration for the constituent of concern.  If the mass
discharged from each individual site is known for a storm event, the mean con-
centration is the total mass divided by total flow.
                                   C-9

-------
                                                        CM
                                                        8
                                                        o
                                                        C\l
                                                        CO
    URBAN RUNOFF
QR =FLOW
CR •= CONCENTRATION
                          /
                            URBAN \
                             AREA  /
STREAM FLOW
             UPSTREAM

        QS^FLOW
        CS = CONCENTRATION
    DOWNSTREAM
    (AFTER MIXING)
Q O = FLOW
CO = CONCENTRATION
     Figure 1.  Idealized Representation of Urban Runoff Discharges
                      Entering a Stream
                          C-10

-------
     Receiving water concentration (CO) is the resulting concentration after
complete mixing of the runoff and stream flows, and should be interpreted as
the storm-event mean concentration just downstream of all of the discharges as
shown in Figure 1.  The four variables that determine the stream concentration
(CO) are:

     •  Urban runoff flow (QR)
     •  Urban runoff concentration (CR)
     •  Stream flow (QS)
     •  Stream concentration (CS)

For an individual rainfall/runoff event, it is possible, in principle, to
measure each of the relevant variables independently.   From those, the average
stream concentration (CO) is calculated:

                         .rn _ (QR CR) + (QS CS)
                         LU ~      QR + QS              ..

If a dilution factor, <|>, is defined as:
CO may be defined in terms of <|> by:

                         CO = [
-------
     The basic approach adopted for the NURP project employs Equations (1)
through (3) and the statistical properties of the four random variables (QR,
CR, QS, and CS) to calculate the cumulative probability distribution of the
downstream concentration (CO) during runoff events.   From this, the probabil-
ity of occurrence or frequency of any target concentration being equaled or
exceeded can be computed.

An essential condition to the use of the approach is that each of the four
variables which contribute to downstream receiving water quality can be ade-
quately represented by a log-normal probability distribution.  Examination of
a reasonably broad cross-section of data indicates that log-normal probability
distributions can adequately represent discharges from the rainfall/runoff
process, the concentration of contaminants in the discharge, and the daily
flow record of many rivers and streams.  Further discussion of the use of log-
normal distributions was presented earlier in this Appendix.

     The approach developed can be applied on a site specific basis, or can
be generalized and applied to a river system, region of the country, or a
series of locations which are characterized by similar rainfall and stream
flow distributions.  The ratio of the stream drainage area (above the urban
area) to the drainage area of the urban area is one of the useful factors
which allows this generalization.   The calculations discussed below consider
a site specific application to illustrate the approach.

Statistical Calculations

     The calculation procedure consists of a number of specific steps as pre-
sented in Table 1.  The theoretical basis for the calculations is described
below and consists of four components as follows:

     a.  Statistical equations of normal and log-normal  random variables

     b.  Statistical properties of the dilution factor

     c.  Statistical properties of the downstream concentration

     d.  Probability of occurrence of selected stream concentrations
                                   C-12

-------
        TABLE 1.   CALCULATION PROCEDURE FOR STATISTICAL PROPERTIES OF
                            STREAM CONCENTRATION

1.   Calculate the estimated mean and variance of the logarithmic transforms
    of each of the four variables (QR, QS, CR, and CS).

2.   Calculate the arithmetic mean and variance of the four variables.  This
    calculation employes formulas that relate the arithmetic mean and vari-
    ance to the mean and variance of the log transformations.

3.   Calculate the mean and variance of the dilution factor (<)>) employing the
    mean and variance of the logarithmic transforms of QR and QS.  The cal-
    culation considers:

    -  Possible correlations between upstream flow (QS) and runoff flow (QR).

    -  Adjustments of the mean and variance of <)> due to the upper bound of
       1.0 on 0.

4.   Calculate the arithmetic mean and variance of <|> as in Step 2.

5.   Calculate the mean and variance of CO using the estimates of the arith-
    metic mean and variance of CR, CS, and <|>.

6.   Plot the log-normal cumulative probability distribution of stream con-
    centration, CO.   The mean and variance of the logarithmic transforms are
    used in developing the plot.

7.   Define CL from a water quality standard or use other criteria to define a
    target concentration limit which will provide protection of beneficial
    water use.

8.   From the log-normal cumulative probability plot for CO, determine the
    probability corresponding to the selected value of CL.

9.   Based on the basic probability value, compute the frequency or recurrence
    interval of water quality problems.
                                   C-13

-------
Statistical Equations for Normal and Log-Normal Random Variables

     Using the pollutant concentration in the stormwater runoff as an example
of the four basic random variables (QR, QS, CS being the other three), the
following notation is used:

     CR   is the random variable itself (runoff concentration).

     CR'  is the log (base e) transformed random variable (£n runoff
          concentration).

     CR   is the arithmetic median of CR.

     u    refers to the mean (e.g., uCR, uCR').

     a2   refers to the variance (e.g., cr2CR, cr2CR') (cr refers to the stand-
          ard deviation).

     v    refers to the coefficient of variation of the arithmetic random
          variable (e.g., vCR).

     Rationships between the arithmetic projections and the properties of a
log-normal distribution are defined by:

     CR = exp (uCR')                                                  (4)
     vCR = Vexp(a2CR') - 1                                            (5)

     uCR = CR  exp(l/2 a2CR')                                         (6)

     aCR = vCR  uCR                                                   (7)

For a random variable such as CR which is distributed log normally, the
value at the a percentile (CR ) is defined as:

                         P[CR < CR ] = a

                         CR  = exp (uCR' + Z  aCR')                   (8)

where Z  is the value of the standardized normal cumulative distribution,

given in Table 2.

Statistical Properties of Dilution

     For the dilution factor () as defined in Equation (2), the value for
any cumulative probability percentile is given by:
                        0   QR + QS  exp(Za  aRS')
                                   C-14

-------
TABLE 2.   CUMULATIVE STANDARD NORMAL DISTRIBUTION
      Probabilities for Values of z
z1
-4.0
-3.9
-3.8
-3.7
-3.6
-3.5
-3.4
-3.3
-3.2
-3.1
-3.0
-2.9
-2.8
-2.7
-2.6
-2.5
-2. A
-2.3
-2.2
-2.1









P(z < z1)
.0000
.0000
.0001
.0001
.0002
.0002
.0003
.0005
.0007
.0010
.0013
.0019
.0026
.0035
.0047
.0062
.0082
.0107
.0139
.0179









z1
-2.0
-1.9
-1.8
-1.7
-1.6
-1.5
-1.4
-1.3
-1.2
-1.1
-1.0
- .9
- .8
- .7
- .6
- .5
- .4
- .3
- .2
- .1
Values
z1
-3.090
-2.576
-2.326
-1.960
-1.645
-1.282
-0.6745
P(z < z'
.0228
.0287
.0359
.0446
.0548
.0668
.0808
.0968
.1151
.1357
.1587
.1841
.2119
.2420
.2743
.3085
.3446
.3821
.4207
.4602
of z for
P(z < z'
.001
.005
.010
.025
.050
.100
.250
) z1
0
.1
_ 2
.3
. 4
.5
.6
.7
.8
.9
1.0
1.1
1.2
1.3
1.4
1.5
1.6
1.7
1.8
1.9
Selected
) z'
0.6745
1.282
1.645
1.960
2.326
2.576
3.090
*P(z < z')
.5000
.5398
.5793
.6179
.6554
.6915
.7257
.7580
.7881
.8159
.8413
.8643
.8849
.9032
.9192
.9332
.9452
.9554
.9641
.9713
Probabilities
?(z' < z1)
.750
.900
.950
.975
.990
.995
.999
z1
2.0
2.1
2.2
2.3
2.4
2.5
2.6
2 '.7
2.8
2.9
3.0
3.1
3.2
3.3
3.4
3.5
3.6
3.7
3.8
3.9









P(z < z')
.9772
.9821
.9861
.9893
.9918
.9938
.9953
:9965
.9974
.9981
.9967
.9990
.9993
.9995
.9997
.9998
.9998
.9999
.9999
1.0000









                      C-15

-------
where the variables are defined as before and in addition a2RS' is the co-
variance between QR' and QS'.   The covariance is computed as follows:
                oRS' = Vo-2QS' + a2QR' - 2pRS'  aQS'  aQR'             (10)
                 PRS- = 1     .   This permits CO to follow a log-normal distribution,
which has a number of useful properties.

     An estimate of the log-mean dilution may be obtained by interpolating
between selected a and (1 - a) percent! le values using Equation (9) and the
following:

                          Mt>' = \ ('U-cO)                     (12)

The log standard deviation of dilution may be estimated by the following
formula, which, in effect, determines the slope of the straight line on the
log probability plot:
                                  a

Note that Equations (11) and (12) are valid for a > 50 percent.  To insure
that the estimated dilution falls between 0 and 1.0 somewhat beyond the
95 percent! le, the 90 percent interval bounded by a equal to 90 and 1- equal
to 5 percent was selected.   While the errors introduced by this approximation
will not change the general outcome of the probability estimates, they may be
important in certain cases and are currently being investigated.  Having esti-
mated the log statistics of dilution, Equations (4) through (7) can be used to
compute the arithmetic statistics.
                                   C-16

-------
Statistical Properties of Stream Concentration

     The statistics of upstream concentration (CS), urban runoff concentration
(CR), and dilution (] + CMCS  (i - M403                 (14)

The arithmetic standard deviation of the stream concentration is defined by:
aCO = Vo-z (NCR - uCS)2 + a2CR (a2<|> + (jz) + azCS (az(j) + (1 - u<|>)z)   (14)

The coefficient of variation is calculated by:

                                  CO * 2                              (16)
Based on Equations (4) through (7), the arithmetic statistics may be used to
derive the log statistics as follows:
                              log mean:  M' = V^n (1 + V*CO)         (18)

From the log-statistics information on probability may be developed.

The Recurrence of Selected Stream Concentrations

     The fundamental result of the statistical analysis is the derived cumu-
lative probability distribution of stream event mean concentration; that  is,
the cumulative probability function F(CO).  Graphically, this is shown in
Figure 2.  For a given concentration of interest (CL), the corresponding
probability may be read directly from the plot (see Figure 2).  Alternately,
the value of CO at the a percentile is defined as

                         P = 1 - P[CO < C0a] = l-d                  (19)

                          CO^ = exp(pCO' + Za aCO1)                   (20)

     One way of properly interpreting the probability (P) corresponding to a
given concentration level is the long term average fraction of events with a
stream event mean concentration equal to or exceeding the specified level.
For example, a probability of 0.10 would specify that on average one in ten
events have a stream event mean concentration equal to or greater than the
specified value.

     For the purposes of evaluation and interpretation, it would be useful to
transform the basic probability statistic into a more meaningful or intuitive
form.  By combining the percent of storms which cause various concentrations
to be exceeded with the average number of storms per year, a  time-based reoc-
currence relationship may be established as described below.
                                   C-17

-------
C/D  O
     CL
   UJ
S8
                                                               00
                                   NOTE: LOG-PROBABILITY PLOT
                               i
                              F(CL)
          CUMULATIVE PROBABILITY P  [ CO <  CL ]
Figure 2.   Example Cumulative Probability Distribution Function of
               Event Mean Stream Concentrations
                            C-18

-------
Reccurrence is a definition based (generally) on the marginal distribu-
tion of random variables.   Basically, if P is the probability of a value of
magnitude CL being equaled or exceeded in a given time period, then the re-
currence interval (R) defined as 1/P is the average number of time periods
between exceedances.

     Assuming as discussed above, we have the cumulative probability distri-
bution function of event mean stream concentrations (i.e., F(CO)).  Then:

                              P[CO < CL] = F(CL)                      (21)

If we want annual  recurrence, we need to find the probability that an event
concentration of a given magnitude (CL) is equalled or exceeded in a year.
The statement of the problem is:

             P = 1 - P[COm < CL] = 1 - P[max(C01 .  .  .  CON) < CL]     (22)

where CO  is the maximum event concentration in a year, and N is the number

of events in a year.   Assuming that event concentrations are independent and
identically distributed with a known distribution such as log-normal, equa-
tion (22) becomes:
                        P = P[CO > CL] = 1 - FN(CL)
                                                                      (23)
                            (1 - F(CL))

A first order approximation to this is given by:


                             R = (1 - F(CL)) N                        (24)

As a convenient and meaningful way to interpret the basic probability results,
the average  recurrence interval as defined in Equation (24) was adopted.  A
schematic example of the relationship is shown in Figure 3.

LAKES

     The impact of urban runoff on lakes may be determined by calculating
eutrpphication parameters in the lake (i.e., total phosphorus concentration,
chlorophyll a concentration, and secchi depth) due to the urban runoff and
comparing these values to desired levels.   Total  phosphorus is the prime
variable of interest, with in-lake concentrations calculated using the
Vollenweider method.   Chlorophyll -a and secchi depth, as well as sediment
oxygen demands, are estimated based on available regression equations
relating these variables to total phosphorus.   For ease of classification,
the area ratio (a) defined as the ratio of the urban drainage area to the
lake surface area, will be expressed in terms  of the eutrophi cation
parameters.
                                   C-19

-------
                                                        o
                                                        9

                                                        CO
                                                        CO
 2 O
 < O
 UJ  .
 DC Z



   \
 Qj O
                                     NOTE: LOG-LOG PLOT
AVERAGE RECURRENCE INTERVAL OF STREAM CONCENTRATION

BEING EQUALED OR EXCEEDED IN YEARS
  Figure 3.  Example of the Average Recurrence Interval as  a

         Function of Event Mean Stream Concentration
                        C-20

-------
Relationship Between Area Ratio (a) and Lake Total Phosphorus Concentration

     The relationship between the area ratio and the in-lake total phosphorus
concentration may be derived for the case where the urban runoff represents
the sole source of the total phosphorus loading into the lake.   The method
proposed by Vollenweider is as follows (1, 2, 3, 4):


                               -       W
                               K   (H/i) + vs

     where,


          p  =  total phosphorus concentration (g/m  = mg/1)
                                              2
          W  =  annual area  loading rate (g/m  per yr)

          H  =  average lake depth (m)

          T  =  hydraulic detention time (yr)

          v  =  net settling velocity of TP (m/yr)

Rearranging Equation (1) yields:
     where,

          W  =  loading rate of TP (g/yr)
                                    2
          A  =  lake surface area (m )

          p  =  lake TP concentration (ug/1)

     For the case where total phosphorus loading is generated by the runoff
from the urban area:
                             W = QR CR 3.15 x 107                     (3)
     where,
          QR = average annual urban runoff flow (m /sec)

          CD = average annual total phosphorus concentration (mg/£)
           K

          and 3.15 x 10  is the factor to convert W to the units of (g/yr).

     A runoff coefficient method may be used to relate the flow (QR) to
rainfall as follows:

                           QR = Cv I Ad 3.17 x 10"10.                  (4)
                                   C-21

-------
     where,
                                       3
          QR = average flow as above (m /sec)

          C  = average annual runoff to rainfall ratio

          I  = average annual precipitation (cm/yr)
                                     2
          A. = urban drainage area (m )

Substituting Equation (4) into Equation (3) yields:
                              W=0.1CvIAdCR                      (5)
Substituting Equation (5) in Equation (2) yields:
                   — =  01 C  I C   ^d  = — 2-  H +
                   A.   'Ui Lv L LR  •£    1000  T
                    a                A£
                                            A.
Rearranging and defining the area ratio a = T-     ,.   .


                              a = P p(" + vs)                         (6)
where,
c - 1
p
10 cv i

CR
                                                                      (7)
Thus for given rainfall (I), runoff /rainfall ratio (C ), and runoff quality

(CR) data, the quantity p is calculated from Equation (7).   Using this value

in Equation (6), the area ratio (a) is calculated directly as a function of
the in- lake TP concentration (p, in ug/1) for a given lake geometry and resi-
dence time (H, t).   Alternately, for a desired maximum total phosphorus con-
centration, the maximum value of the ratio of the urban area to the lake
surface area can be determined.

Graphs of Area Ratio (a) for Selected Rainfall and Runoff Conditions

     Based on Equations (6) and (7), graphs of the area ratio versus the lake
characteristic (H/t) are presented in Figure 4 for commensurate ranges of
the values of total phosphorus.  Graphs are shown for two values of the net
settling velocity of total phosphorus (v ) = 10 m/yr used by Vollenweider (3)
and 5 m/yr.  As discussed by Thomann (7), the latter value may be more re-
presentative of shallow lakes (depths less than 3 meters) where resuspension
may be significant.  Three annual rainfalls of 12, 24, and 36 inches (30, 61
and 91 centimeters, respectively) are used to allow for regional variations.
For all graphs, values of the average concentration of total phosphorus in
the urban runoff is equal to 0.35 mg/£, and the volumetric runoff to rainfall
ratio is equal to 0.3.
                                   C-22

-------
    1000 •=
55
DC
<
LU
O

£
DC

CO
LU
*
cc
<

LU
O
CC
Q


<
CD
DC
D
u_
O

O
*
     100 -.
-*
0

l
      1.0 -
      0.1
              100

              -50

               30
              -20

               10
                    T.PHOS.
                FIT)  i  I I 1 I II Ij  I

                 1.0      10
                                            1000 -g
                                    100 -
                                              0.
                        100     1000             1.0      10      100     1000

(a) RAINFALL OF 12 IN/YR AND vs OF 10 M/YR  (c) RAINFALL OF~ 36 IN/YR AND vs OF 10 M/YR
    1000 .q
     100 -
                 1.0      10     100     1000

         (b)  RAINFALL OF 24 IN/YR AND vs OF 10 M/YR




                   H/T - LAKE DEPTH HYDRAULIC DETENTION TIME  (M/YR)
         Figure 4.  Graphs  of  Area Ratio Versus Lake Characteristics (H/t)
                                       C-23

-------
55
DC
<
UJ
DC


CO

LLJ
*
<

O
<
CD
DC

Li.
O

O
t-

DC

v
    1000
     100
                                    1000-g
      0.1
                                     0.

        1.0       10      100     1000             1.0      10     100     1000

(d) RAINFALL OF 12 IN/YR AND vs OF 5 M/YR     (f) RAINFALL OF 36 IN/YR AND vs OF 5 M/YR
    1000^
     100-
      0.1
                1.0      10      100    1000


        (e) RAINFALL OF 24 IN/YR AND vs OF 5 M/YR
                 H/T - LAKE DEPTH  HYDRAULIC DETECTION TIME (m/yr)
  Figure  4.   Graphs of Area Ratio Versus  Lake  Characteristics (H/i) (Cont'd)
                                     C-24

-------
The average total phosphorus concentration was derived from data gathered in
NURP projects nationwide.  Based on pooled data from the current NURP data
base (i.e., 13 cities, 51 sites, 737 events) the average total phosphorus con-
centration was calculated to be 0.35 mg/I.

     The parameters for each graft in Figure 4 are as follows:


                                 I               Cv              CR
      Fig         (m/yr)         (in/yr)         (in/in)         (mg/1)

      a             10             12              0.3            0.35
      b             10             24              0.3            0.35
      c             10             36              0.3            0.35
      d              5             12              0.3            0.35
      e              5             24              0.3            0.35
      f              5             36              0.3            0.35

For these parameters, p as defined by Equation (7), is only a function of the
rainfall and equals 0.0315, 0.0157 and 0.0105 for annual rainfalls of 12, 24
and 36 inches, respectively.

     For any specific lake where data are available, local rainfall and run-
off (volumetric runoff coefficient and runoff quality) data should be used to
calculate p according to Equation (7).  In addition, in-lake TP concentrations
and TP mass inputs should be used to select the net settling velocity of total
phosphorus for the lake.

Area Ratio (a) vs. Chlorophyll, Secchi Depth, and Sediment Oxygen Demand

     In order that eutrophication measures other than total phosphorus may
be used to establish limiting urban area ratios, regression equations between
total phosphorus and the additional variables are used.

     For chlorophyll-a, the regression equation according to Dillon and
Rigler (5) is used since it is based on a wide range of chlorophyll a and
total phosphorus data (TP < 200 ug/1, Chl-a < 260 ug/1);

                    log1Q Chl-a = 1.449 Iog1()ps - 1.136               (8)

     where,

          Chi a = chlorophyll-a concentration (ug/1)

          p     = average total phosphorus concentration for the spring
           s      period (mg/1)
                                   C-25

-------
Letting p  = 0.9p, where p is the average concentration for the summer period,
and rearranging, p is expressed as:

                                    0.690 loginCHl-a
                       p = 6.76 x 10         iu                       (9)

Substituting Equation (9) into Equation (6) results in an expression for the
area ratio (a) as a function of the chlorophyll-a concentration:

                               0.690 loginChl-a
               a = 3 (6.76 x 10         iu     ) ((HA) + vs)         (10)

     The expression relating secchi depth to total phosphorus concentration
is from Rast and Lee (6):

                       log1QZ = -0.359 Iog10p + 0.925                 (11)

     where,

          Z = the secchi depth (m)

Solving Equation (11) for p and substituting into Equation (6) yields

                                 -2.79 log  Z
                a = p   (380 x 10         1U ) ((H/T) + vg)           (12)

     For sediment oxygen demand Rast and Lee (6) report:


                       1og10Sb = °'467 log!0p " 1-07                  (13^

     where,

          S.  = the sediment oxygen demand (g/m2 per day)

Solving Equation (13) for p and substituting into Equation (6) yields:

                                 2.14 log,nS.
                a = p • (195 x 10        1U D) ((HA) + vg)           (14)

Although the sediment oxygen demand is not a direct measure of eutrophica-
tion, it can be used to calculate dissolved oxygen concentrations in the
hypolimnion when reaeration rates and vertical transport coefficients are
available or may be estimated.   Equations (11) and (13) are valid up to a
maximum total phosphorus concentration of approximately 100 ug/1.

     Graphs of the area ratio versus the lake characteristic (H/i) may be
developed for chlorophyll-a, secchi depth, and sediment oxygen demand using
Equations (10), (12), and (14), respectively (see Figure 4 for the total
phosphorus graphs).
                                   C-26

-------
References

1.   Vollenweider, R.  A., "The Scientific Basis of Lake and Stream Eutrophica-
    tion, With Particular Reference to Phosphorus and Nitrogen as Eutrophica-
    tion Factors," Tech. Rep. OECD, Paris, DAS/CSI/68, 27, 1968.

2.   Vollenweider, R.  A., "Moglichkeiten und Grenzen elementarer Modelle der
    Stoffbilanz von Seen" (Possibilities and Limits of Elementary Models
    Concerning the Budget of Substances in Lakes), Arch.  Hydrobiol.  66, 1969.

3.   Vollenweider, R.  A., "Input-Output Models with Special Reference to the
    Phosphorus Loading Concept in Limnology," Schweiz. J. Hydrol. 37, 1975.

4.   Vollenweider, R.  A., "Advances in Defining Critical Loading Levels for
    Phosphorus in Lake Eutrophication," Mem.  Inst. Ital.  Idrobiol.,  33, 1976.

5.   Dillon, P. J., and Rigler, F. H., "The Phosphorus-Chlorophyll Relation-
    ship in Lakes," Limnology and Oceanography, Vol.  19 (5), September, 1974.

6.   Rast, W.,  and Lee, G. F., "Summary Analysis of the North American (US
    Portion) OECD Eutrophication Project:   Nutrient Loading-Lake Response
    Relationship and Trophic State Indices,"  for USEPA, ORD, Corvallis,
    Oregon ERL, EPA-600/3-78-008, January 1978.

7.   Thomann, R. V., "The Eutrophication Problem", in Waste Load Allocation
    Seminar Notes, prepared by Manhattan College for USEPA, Washington, D.C. ;
    August, 1981.

8.   Hydroscience, Inc. ,  "A Statistical Method for the Assessment of Urban
    Stormwater," for USEPA, Office of Water Planning and Standards,
    Washington, D.C.  EPA 440/3-79-023, May, 1979.

9.   Di Toro, D. M., Mueller, J. A., and Small, M. J., "Rainfall-Runoff and
    Statistical Receiving Water Models," Task Report 225 of NYC 208 Study
    prepared by Hydroscience, Inc., for Hazen and Sawyer, Engineers and the
    New York City Department of Water Resources, March 1978.

10. Hazen and Sawyer, Engineers, "Storm/CSO Laboratory Analyses", Task
    Report 223, Volume I and II of NYC 208 Study, prepared for the New York
    City Department of Water Resources, 1978.
                                   C-27

-------
                         C-3.   EFFECTIVENESS OF CONTROLS



                         EFFECTIVENESS  OF  STREET SWEEPERS









Precipitation Statistics and Sweeping Intervals




     Street sweeping operations are set up for a fixed interval, e.g., sweep




once per week.  If the average time between rainfall events is much less than




the sweeping interval, then much of the material would be washed away by the




rain.  Hence, the street sweepers would be relatively ineffective.  It helps




to examine the rainfall statistics in the study area.  Table 1 summarizes




runoff statistics for four U.S. cities for which these data are available.




The national average values, used in this interim report, provide rough esti-




mates of the size of runoff events, the time between storms and the number of




events per year.  These numbers will be refined as the study progresses.




     The results indicate a mean runoff per event of 0.12 inches.  The time




between storms is about three to four days.  Correspondingly, about 100 storm




events per year can be anticipated.




     The coefficient of variation is the standard deviation divided by the




mean.  If the probability distribution is assumed to be a log normal, then




the cumulative probability distribution can be estimated directly.  The solu-




tions for coefficients of variation of 1.0 and 1.5 are shown in Figure 1.  This




figure can be used to estimate, say, the percent of runoff events larger than




0.24 inches.  From Table 1, the mean runoff event is 0.12 inches.  Thus, the




events of interest are those which are at least twice the mean runoff.  From




Figure 1, for y/y =2.0 and a coefficient of variation = 1.5. (from Table 1),




12% of the runoff events are greater than or equal to 0.24.inches.




     Table 2 summarizes the statistics on the expected frequency of times be-




tween rainfall events for these four U.S.  cities.  On a national average, over
                                     C-28

-------
              Table 1.   Twenty-Five Year Rainfall Statistics For
             Four U.S.  Cities;  Source:   Driscoll and Assoc., 1981
City
Boston, MA
Atlanta, GA
Davenport , IA
Oakland, CA
Average
Runoff Volume, In/Event
Mean
0.11
0.17
0.13
0.06
0.12
Cost of
Variation
1.67
1.37
1.37
1.62
1.51
Time Between Storms, Days
Mean
2.81
3.75
4.08
3.98
3.66
Cost of
Variation
1.06
0.93
1.01
1.60
1.15
Events
Per
Year*
130
97
89
92
100
*  Events per year equals 365 days divided by mean time between storms,
                                    C-29

-------
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.1
>•!•* wv -tit $9 va »i VQ aa 70- AO jo 40 10 20 10 j 21 03 02 01 a at 001
Ivijiure 1. Graphical Solution lit c Log-Normal Distribution for Coefficient of Variation » 1.0 and 1.5.

-------
     TABLE 2. Expected Time Between Rainfall Events for Four U.S. Cities Based on 25 years of Hourly Rainfall Data.
              Data from Driscoll and Assoc.,1981.
INTERVAL,
DAYS
0 to 1
1 to 3
3 to 7
7 to 14
14 to 21
> 21
TOTAL
NUMBER OF EVENTS /YEAR
BOSTON,
MA
27
64
30
8
1
0
130
ATLANTA,
GA
12
43
30
11
2
0
98
DAVENPORT ,
IA
8
38
29
11
2
2
90
OAKLAND,
CA
22
33
24
8
3
2
92
TOTAL
69
178
113
38
8
4
410
% OF
TOTAL
16.8
43.4
27.6
9.2
2.0
1.0
100.0
CUMULATIVE
% OF
TOTAL
16.8
60.2
87.8
97. On
99.0
100.0
100.0
?

-------
60% of the storm events occur within three days while 97% of the time rains




within two weeks.  These patterns vary seasonally.  The most notable seasonal




variation is along the West Coast due to the dry summers.  Of course, sweeping




is not practical during months when snow and/or freezing weather occurs.




Characteristics of Street Solids




     The results of street dirt characterization studies for 27 water quality




constituents are shown in Table 3.  The nationwide average is the median of




the cities for which data are presented.. The median is used because of the




high variability in some of the data.




     Street contaminants comprise only a fraction of the materials washed from




urban areas.  The balance comes from other impervious and pervious areas,




and the atmosphere (Castro Valley, 1979).




     Table 4 presents various sources for major pollutant groups in the




runoff.  The only pollutant group shown to be significantly related to street




surface wear and use are heavy metals.  Bacteria are thought to originate




mainly with animal fecal matter indirectly deposited on the street or on




adjacent land.  Most of the nutrients are thought to originate from vegeta-




tion litter in landscaped areas, undeveloped lands and directly on the street




surface.  Oxygen demanding materials (BOD and COD) in the runoff are mostly




associated with litter and landscaped areas, while sediment sources are




mostly thought to be vacant lands and construction sites.




     Table 5 summarizes suitable control measures for different types of




source areas.  As an example, street cleaning can only be utilized on streets




and parking lots to control street surface participates and litter.  Street




cleaning can therefore not be expected to significantly change the runoff




yields of the pollutants that are not significantly associated with the street




surface (such as organics and nutrients).
                                     C-32

-------
Table 3.  Average Chemical Quality of Street Dirt (Pitt,  1981)

Constituent:
Volatile Solids
COD
BOD5
Total P
Ortho PO,
Total Kjeldahl N
Sulfur
Arsenic
Cadmium
Chromium
Copper
Iron
Lead
Manganese
"Nationwide"
Average*
75,000
80,000
10,000
500
100
1,600
1,100
15
3
200
100
22,000
1,000
500













Constituent:
Mercury
Nickel
Strontium
Zinc
Total Colif. bact.
Fecal Colif. bact.
Fecal Strps. bact.
Asbestos
Bis (2-ethylhexyl
phthalade)
Dieldrin
Methoxychlor
PCB's
PGP's
"Nationwide"
Average*
.08
20
15
300
4 x 10 org/gm
3,000 org/gm
	
175,000 fibers/gm
25
0.03
1
0.7
3
   All units are in rag/kg of street dirt, unless otherwise noted.
                                     C-33

-------
    Table 4.  Sources of Contaminants (Pitt ?, 1979)
Common
Urban Runoff
Pollutants
Sediment
Oxygen
Demand
Nutrients
Bacteria
Heavy
Metals
Street
Surface
Wear




X
Automobile
Wear and
Emissions


X

X
Parking
Lots




X
Litter

X
X
X

Vacant
Land
X

X
X
-
Landscaped
Areas

X
X


Con-
struction
Sites
X




Table 5.  Applicability of Control Measures (Pitt ?, 1979)
Suitable
Control
Measures
Street
Cleaning
Leaf
Removal
Repair
Streets
Control
Litter
Clean Catch
Basins
Control . j
Construc-
tion Site
Erosion 1
Street
Surface
Wear
'. X

X

X

Automobile
Wear and
Emissions
X



X

Parking
Lots
X
X
X



Litter
X
X

X


Vacant
Land



X


Landscaped
Areas

X




Con-(
struction
Sites '




X
.
X
                      C-34

-------
     Table 6 presents the Castro Valley study area runoff yields of various




parameters for the street surface, non-street urban and undeveloped areas




of the watershed.  This information was obtained from studies conducted in




Castro Valley during the recent 208 study and from the literature.  Also




shown in Table 6 are the percentages of the source area contributions for




each parameter compared to the total runoff loads.  Most of the lead is




associated with street surface particulates, with very little lead ori-




ginating from non-street urban and undeveloped areas of the watershed.




Most of the total solids yields for the study area are associated with




the undeveloped area.  Non-street surface developed areas are thought




to contribute most of the oxygen demand, nutrient and bacteria yields.




Effect of Rain on Street Loads




     Precipitation has two effects on street loads:




     1)  washoff of some or all of the material on the streets; and




     2)  buildup of residual material on the streets after the storm due




         erosion and other sources.




     Erosion occurs as a result of relatively large storm events.  Smaller




storms would be expected to flush the atmosphere, and the directly connected




impervious areas.  Thus, we would like to know the size of storm events which




cause street washoff without significant erosion.




     Pitt (1981) has developed a summary table relating runoff volume to the




ratio of initial street load to the load removal by the storm event.  The




results are shown in Table 7.




     For example, the ratio for arsenic is 0.16 for a runoff volume of 1.3




inches.  The arsenic leaving the area comes from the street and elsewhere,




e.g., atmosphere, rooftops, lawns.  The ratio of 0.16 indicates that the ini-




tial load on the street was 1/6 of the total load leaving the area.  It is






                                      C-35

-------
       Table 6.   Castro Valley Creek Runoff Yields  (Pitt ?, 1979)
1 Parameter
Total Solids
Sus. Solids
, COD
i BODs '
; Total N
: OPO,*
; Pb
i *n
Total Colif.(org)
Fecal Colif.(org)
Street Surface1
Tons/Yr %"
160
80
2.1
1.1
0.1
0.013
1.0
0.072
SxlO10
8xl09
33
32
2
7
2
9
100
24
« 1
« 1
No n- Street2
Urban
Tons/Yr %
10 2
60 27
69 72
12 76
2.4 51
0.12 84
0 0
0.23 76
6x1Qi" 100
3xlQi" 100
Undeveloped3
Tons/Yr X
320 65
.95 41
25 26
2.5 17
2.2 47
0.01 7
0 0
0 0
? ?
? ?
Total
Tons/Yr
490
235
96
16
4.7
0.14
1.0
0.3
6xlQi"
3xlQl"
1  From Alameda  County measurements in Castro Valley  during 208 Study
2  Alameda County  208 SWMM calculations minus street  loadings
3  Data from "the  literature" (estimates)
"  Percentage contribution of source related to  total  annual runoff yield
                                    C-36

-------
Table  7  .   Street Loading Sensitivity to Rxmoff Yield (Pitt , 1981)
Runoff
Volume
(in)
4.3
3.3
2.0
1.3
0.66
0.33
0.13
0.05
0.01
Total
Solids
0.080
0.085
0.13
0.22
0.50
1.2
15
50
500
COD
0.020
0.024
0.054
0.095
0.20
0.45
3
10
100
Total
P
0.020
0.024
0.044
0.080
0.20
0.50
3
10
100
Ortho
P04
<0.001
0.001
0.0017
0.0026
0.0080
0.020
0.2
1
10
Total
Kjeldahl
• N
0.020
0.020
0.034
0.045
0.075
0.20
2
10
100
Arsenic
0.044
0.054
0.095
0.16
0.50
2.0
15
50
500
Copper
<0.06
<0.06
0.06
0.09
0.16
1
10
25
250
Lead
0.10
0.12
0.20
0.35
0.90
2.0
20
50
500
Zinc
0.020
0.025
0.044
0.062
0.13
0.36
3
10
100
                         C-37

-------
impossible to tell from this table alone the exact origin of the material or




what portion came off the street.  For example, arsenic in the atmosphere




would wash out with the arsenic in the street.  Arsenic in the soil would




probably wash out later.  However, in order to obtain a rough estimate of




the type of storms that flush the streets, assume that some or all of the




street contamination is removed first then, the remaining removals are assumed




to come from other sources.  Thus, for arsenic, a ratio of 2.0 means that 50%




of the arsenic in the street was removed while none of the other sources of




arsenic left the study area.  Figure 2 shows the percent washoff vs. runoff




rate for the eight constituents shown in Table 7.  It is evident from Figure 2




that the primary area of interest is runoff volumes from 0.1 to 0.4 inches.




Lighter storms (< 0.1 in.) do not cause much street washoff whereas larger




storms (> 0.4 in.) contribute much more contaminants from sources other than




street runoff.




     Given that the main area of interest is runoff values ranging from 0.1




to 0.4 inches, the results of Table 7 and Figure 2 can be used to estimate




the percent of storm events falling in this range.  The lower bound of




0.1 in. of runoff corresponds to the 50% level whereas the 0.4 in. values




corresponds to the 90 to 95% level (from Figure 1).  Thus, the main area of




interest is in the larger storm events up to the 90 to 95% level.  Alterna-




tively, only about one half of the storm events flush the streets clean.




Thus, the approximate time between these rainfall events is about one week,




twice the average time between storms.




Street Pollutant Build-up Rates




     Pitt (1981) has summarized the results of work to date on the rate of




accumulation of street solids based on five catchments in California and one




in Belleview, Washington—all west coast stations for which it is possible to




obtain information on long-term accumulation due to the dry summers.  The





                                     C-38

-------
     CO
     u
     c
     ta
     e
     •H

     TO
     4J
     C
     o
     CJ
     cu
     0)
     U-l
     O
     co
     fl
        25 -
                       .1
.'2
.3
.4
.5
.6
                                 Runoff  Volume, in./event
Figure 2  .  Washoff of Street Contaminants for Residential Areas  in Western U.S.
             (Pitt,  1931)
                                             C-39

-------
national estimates, shown in Table 8, are based on calculated values using



the curve of best fit for the original data.  These national estimates are



plotted in Figure 3.  All of the data plot as straight lines with positive



intercepts representing a base loading and constant growth rates (Ib/curb



mile/day) of 38.7 (industrial), 20.0 (residential), and 15.0 (commercial).



     From the previous section, the average time between storm events that



flush the streets is about one week.  Thus, the expected accumulations can



be taken directly from Table 8.  The numbers in Table 8 and the lines in



Figure 3 are based on fitting functions to the available data.   However, the



actual data exhibit quite a bit of variability as is evident in the street



loadings reported for the Surrey Downs catchment in Belleview,  Washington (see



Figure 4).  No trends are evident for this data set.  About all one could say



is that the expected load is about 366 Ibs/curb mile independent of the days



of accumulation.



Street Sweeping Effectiveness;  Single Site With and Without Cleaning



     Figure 5 shows performance data (based on a two-day sweeping interval) for



the Surrey Downs study area.  Two lines are drawn:  a 45° line indicating zero



removal, and a regression line relating load in to load out.  The regression



line for a sweeping interval of 2.0 days, is



          L_ = 180 + 0.45 LT                                      (1)
           r               L


where     L  = residual load (after sweeping), Ibs/curb mile, and



          L  = inital load, Ibs/curb mile.



The intersection of these two lines is the graphical solution to the problem of



finding the minimum inital load for which sweeping has a positive effect.  It



is counterproductive to sweep where the streets are cleaner  than this minimum



initial load since the solids generation form street abrasion exceeds the



removal by the sweepers.  Thus, the origin of the axes can be translated along



the 45° line to (327,327)  as indicated on the figure.   With the transformation,




                                     C-40

-------
the gross removal efficiency, e, is




          e = 1 - LF'/Ll' = l ~ °*45 = °'55



where   L ' = translated value of L  (i.e., L -327), Ibs/curb mile, and
         r                         r         r
        L '  = translated value of L  (i.e., L -327), Ibs/curb mile.




     The data set shown in Table 9 indicates negative removals for 13 out of




the 27 sweepings.  The physical reason for negative removals is that the clean-




ing process itself erodes the street surface especially when the streets are



relatively clean as they would be in this case with only a two-day interval



between sweeping events.  Thus, the overall net efficiency, e.,, for a two-day



interval is



          e  = 1 - LP/L.J. = 1 - 24.7/376.1 = 6.6%                   (3)



where     L_ = mean residual load, Ibs/curb mile,
           r


          LT = mean initial load, and Ibs/curb mile.



Higher efficiencies can be acheived by not sweeping when the initial loads are



relatively light.  If the general regression equation is




          LF » a + bLz                                             (4)



then sweeping should begin when L^ = LT<  Combining these two equations yields



          (L,).  - a + b(L )                                      (5)
            1 mm          I mm



or        (LT)m-n »  T^K                                         (6)
            I mm    1 - b


For Surrey Downs, a = 180, b = 0.45.  Thus, (LT) .  = 327 Ibs/curb mile.  How-
                                              I nun


ever, this information is not very useful since the operator of the sweeper has



no simple way of measuring LT.  Thus, the appropriate estimate of  overall  effi-



ciency is e,..  For this example, the data indicated that sweeping  every other



day is relatively nonproductive.



     Pitt (1981) has summarized the regression relationships for four types



of parking conditions and three types of street surfaces.  The results are



shown in Table 10.  In all cases, a simple linear relationship exists between the
                                     C-41

-------
     Table 8.  Total Solids Accumulation on U.S.  Streets (Pitt, 1981)

DAYS OF
ACCUMULATION
0
1
2
3
4
5
7
10
15
TOTAL SOLIDS, Ib./curb mile
RESIDENTIAL

400
420
440
470
490
510
530
600
700
INDUSTRIAL

670
710
750
790
830
870
940
1050
1250
COMMERCIAL

300
315
330
345
360
375
405
450
525
     1000
= 670 +38.7 t
                            INDUSTRIAL
01
1—I
•H
e
M
3
u
CO
Q
O
CO

H
W
Cd
      750
500
                  L  =  400 +  20.0  t     RESIDENTIAL
      250
                      L  =  300 +  15.0  t     COMMERCIAL
                       c
                                                         10
                                                                           15
                         DAYS OF ACCUMULATION,  t
              Figure 3.   Street Loading vs.  Days of Accumulation (Pitt, 1981)

                                   C-42

-------
Table 9.  Solids Removal Efficiencies of Street Sweepers,
              Surrey Downs and Lake Hills -
                 Twenty-Seven Sweepings
N
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
I
Mean
Surrey Downs
Loadings (Ib/curb mile)
Before, L
529
538
695
713
326
303
295
371
424
333
406
472
437
384
290
305
235
237
281
336
352
•>S1
328
302
363
296
353
10,155
376.1
After, LF
496
545
442
412
265
317
386
323
332
353
315
423
427
444
304
375
252
245
295
352
320
249
315
306
364
285
345
9,487
351.4
Difference
33
-7
253
301
61
-14
-91
48
92
-20
91
49
10
-60
-14
-70
-17
-8
-14
-16
32
7.
13
-4
-1
11
8
688
24.7
Lake Hills
Loadings (Ib/curb mile)
Before, L
380
238
295
292
265
228
229
244
216
124
182
198
250
167
150
161
no •
108
159
261
144
27"
242
194
109
185
190
5,591
207. 1
After, Lp
330
240
267
270
311
239
200
250
214
148
199
211
235
123
148
147
112
121
145
210
179
197
214
191
310
300
215
5,726
212. 1
Difference
50
-2
28
22
-46
-11
29
-6
2
-24
-17
-13
15
44
2
14
-2
-13
14
51
-35
73
28
3
-201
-115
-25
-135
-5.0
                          C-43

-------
                      Table  10.   Estimated  Street Cleaner Productivity (Pitt, 1981)

Parking
Condic ions
Light

Moderate

Extensive
Short
Term
Extensive
Long
Term
Smooth Asphalt

Range
for
L,
100-250

100-230

~
100-230

Equation
L = 150+
0.36 1.
L = 110+
0.54 L
~
LF = 55+
0.75 LT

»in
1310

1290

1330
1330
Removal
Efficiency
at
(LX)A
max
0.03

0.02

0.03
0.03
(L )    = a/(l-b) from equation L  = a + bL
 I  min                    r       l
Efficiency = l-(a+b(L )    )/(L )

-------
UJ
 i
CO
(Tt
   SURREY  DOWNS  STREET  LOnDINGS-TOTflL  SOLIDS
   800
   70Q_



   60£L



   50fl_
CD

-  40£L

LO
z


g  30fl_
o
   20£L
   10D_
   0
      "*— * « *   4

      y«  4
       01234567891
                         n213141516171Bi'9
                               129232425752/2825303]32333435


      DRYS OK RCCUKULRTION (FOR 04/02/80 TO 07/132/81)


Figure 4. Surry Downs Street Loadings - Total Solids (Pitt, 1981)

-------
 SURREY  DOWNS TOTflL  SOLIDS  PRODUCTIVITY
60Q
0
    0
50
100 150  200 250  300 350  400 450  500 550  600 650  700 750
         INITIRL LORD (LB5/CURB-MILE) - LT
     Figure 5. Surrey Downs Total Solids Productivity (ritt, 1<">8])

-------
initial and final loads.  The user only needs to know the mean initial load,



LT, to estimate overall net efficiency, i.e.,



          eN = 1 - LJ./LJ = 1 - (a + bL-^/Lj                       (7)



For example, the regression equation for rough asphalt with moderate parking



conditions is



          LF - 360 + 0.44 LZ                                      (8)



Assume LT = 600.  Using equation (6), efficiency is




            e  = i .  360  +  0.44 (600)  = _

            £N   L         600                U'U4'



a negative number.  If LT = 650, the upper limit on the range of L , then e^ =



0.01.  Using equation (6), the minimum L  to obtain a non-negative efficiency



is


                        360
          (LT)
            I'min    1 - 0.44
=643 Ib/curb mile
Consequently, it would be unwise to sweep in this case.  Table 10 shows (L )
                                                                          I mln


for those ten equations.  In two of the ten cases efficiencies are negative for



the entire range of L .  The maximum attainable efficiency in the specified



range of L  is only 4%.  Thus, these results indicated very poor performance



for street sweepers.



Effectiveness of Street Sweeping Programs



     If the street accumulation data do not show a trend over a time, (e.g.,



the Surrey Downs data in Figure 4) then the effectiveness of the street



sweeping program can be evaluated simply by determining the average street



loading with and without a street cleaning program.  The Surrey Downs data



are summarized in Table 11.



     Table 11. Results of Surrey Downs Sweeping Studies (Pitt, 1981)
Condition
No sweeping
Sweep 3 times /week
Immediately after
sweeping
Average Street Loads,
Lb/curb mile
366
333
330
% Reduction
— r
9.0
9.8
                                    C-47

-------
These results indicate that frequent sweeping reduces total solids only by




9 or 10 percent.  Thus, if 70% of a heavy metal such as lead originates in




the street, then the expected impact of sweeping three times per week is only




(9%) (.7) = 6.3% reduction in the total (street and non-street) lead load.




     The effectiveness of street sweeping can be estimated by selecting




two similar areas, sweep one of these areas, and compare the loads leaving




the two areas.  Results of this procedure as applied to Surrey Downs and




Lake Hills are described below.




     Figures 6 and 7 are plots of storm runoff yields for both basins for




total solids and lead.  Most of the available data are only for the period




when Lake Hills was cleaned and Surrey Downs was not cleaned.  Therefore,




basin calibrations are not available, even though the basins were selected




with similarities in mind.  These examples, along with the above discussion




of the effects of street cleaning on street dirt loads, demonstrate how poor




this method of analysis is.   The first problem is selecting the appropriate




runoff data for comparisons.  Eellevue has more available data than any other




NURP project:  116 storms.  Only about 50 of these 116 storms include complete




monitoring simultaneously from both the control and test basins.  If STORET




data are used, then there is no way of knowing which storms were completely




monitored, and which storms need to be combined.  Another serious problem




is the differences in rainfall observed at both sites during the same storms.




Correlations in rain quantities were made between the Lake Hills and Surrey




Downs sites to a relatively high degree of significance, but individual rains




did vary substantially.  Therefore, of the 50 complete monitoring sets, only




26 storms resulted in total rain quantities within 25% of each other.  Previous




correlations showed a very "strong" relationship between rain quantity and




runoff pollutant yield (almost 1 to 1 for rain quantities up to 0.5 inch).







                                    C-48

-------
n
          RUNOFF  CONTROL  BY  STREET  CLERNING-TOT.SOL.
          10.
          0
                 1
12  13  14  15
         4   5   6  7   8   9   10  11

         Lfl£E HILLS (CLEPNE3) LBS/8CRE/5TORM

Figure 6. Runoff Control By Street Cleaning-Total Solids (Pitt, 1981)

-------
            RUNOFF  CONTROL  BY  STREET  CLERNING-LEFID
n

Ln
O
                      32E-C33E-Q34E-035E-C
36E-037E-038E-039E-03.01  .01
.015
                             LRK.E HILLS (CLEflNED) LB5/HCRE/5TCRM

              Figure 7.  Runoff Control by Street Cleaning-Lead (Pitt, 1981)

-------
Therefore, a 25% difference in total rain at the two sites can be expected




to produce nearly a 25% difference in runoff pollutant yield.  As noted




above, extensive street cleaning compared to no street cleaning reduces




street loads by less than 10%, and the resultant runoff yields for most pol-




lutants could be expected to be much less.  Therefore, even with "perfect"




basin calibrations, the noise in the system due to rain differences can be




easily greater than twice the expected difference due to street cleaning.  If




rains within, say 10%, were selected, only a very few events would be avail-




able for study.  Belleview probably has more consistent rains over the city




than many other NURP cities.  Fortunately, the "information component" (street




cleaning effects) is expected to be greater in the other NURP cities.




     Regression lines in Figures 6 and 7 show that the Surrey Downs catchment




(the "control") produces lower total solids and lead loads than the




"cleaned" Lake Hills basin.  In fact, only 25% of the storms had smaller unit




area yields in the "cleaned" basin when compared to the "control" basin.




Again, the basins have not yet been "calibrated".  The ongoing sampling scheme




will allow these direct comparisons to be made, along with basin calibrations,




but other data will also be collected allowing alternative analytical method-




ologies.  This direct comparison appears to be the simplest procedure, but




without intimate knowledge of the data set (for completeness and compacta-




bility) and without adequate calibration periods, it can be extremely mis-




leading.  Thus, the analysis of the sensitivity of street loads to runoff




yields and simple productivity relationships to identify the cleaning effort




needed to obtain specific street loads should be the primary methodology.




Comparisons between control and test basins should also be made, but only




after careful review of the data.




Cost-Effectiveness of Street Sweeping Programs




     Unit costs for sweeping streets in Alameda County, California were found






                                     C-51

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to be $15.00/curb mile (Pitt, 1981).  Heaney et al. (1977) used a value of




$7.00/curb mile based on 1976 survey data of the American Public Works Asso-




ciation.  For this inital assessment of control effectiveness a unit cost of




$12.00 per curb mile is assumed.




     Heaney and Nix (1977) developed a procedure for evaluating the relative




cost effectiveness of street sweepers as compared to detention basins and




other controls.  The performance of the system was simulated using a simple




model which assumes:




     a)  zero base load and a constant buildup rate per day,




     b)  an exponential washoff relationship based on the assumption that




         one-half inch of runoff per hour removes 90% of the remaining




         street contaminants.,




     c)  a constant percent of the load is available to be swept,




     d)  rainfall does not act as a source of contaminants, and




     e)  removal efficiencies are independent of loadings.




Information presented earlier in this section indicates that several of these




assumptions are untenable.  A given level of control applied over several




months results in a known average loading on the street.  Insufficient data




exist to support the assumptions of a positive linear or nonlinear accumulation




of solids with time.  Unfortunately, it is very expensive and time consuming




to sweep for several months or a year at a fixed interval to obtain a single




estimate of removal efficiency.  The type of curve we hope to get looks like




Figure 8.  However in this case, each data point is based on several months




of sampled data.  Figure 8 shows additional removals as street sweeping in-




tensifies.  However, we are limited by two primary factors:  only a portion




of the total load is sweepable; and relatively intensive sweeping generates




added loads through street abrasion.
                                    C-52

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  100
 eg
 
-------
     Given Figure 8, the total and marginal cost curves as a function of




pounds removed can be developed.  For this hypothetical production function




(Figure 8) and assuming a unit cost of $12.00/curb mile, the total and mar-




ginal cost curves shown in Figure 9 can be developed.  For this hypothetical




case, marginal costs are in the range of $ 0.50 to 3.00/lb removed.  These




unit costs can then be compared to the unit costs of other control options.




Summary and Conclusions—Street Sweepers




     Analysis of the available NURP data and earlier studies indicates the




following:




     1)  Street sweepers can remove suspended solids (up to 30-40%) and




         metals (up to 90%) since significant portions of the urban wash-




         off from these two categories of contaminants originate on the




         streets.  Sweeping will not be effective in removing organic




         contaminants, nutrients, and/or coliforms since these constitu-




         ents wash off from non-street areas.




     2)  Street loadings may or may not increase with time since the last




         storm.  Limited NURP data do not show any trends.




     3)  Streets are washed by runoff events in the range from 0.1 inch to




         0.4 inch.  This range of events accounts for about 40% of the




         total events per year.  About 50% of the events do not cause




         significant washoff (< 0.1 in) while 10% of the events are large




         enough (> 0.4 in) such that non-street loads dominate.




     4)  The expected time between runoff events which wash the streets




         is about one week.




     5)  The expected total solids load after a week in Ibs/curb mile is




         530 (residential), 940 (industrial), and 405 (commercial).




     6)  The reported removal efficiencies for single or paired basins are




         quite low, i.e., < 10%.  If available data are a representative




                                    C-54

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3000  -
                500        1000         1500

                       Lbs. Removed, x
2000
                                                                   $3.00
                                                                   $2.50
                                                                 -  $2.00
                                                                   $1.50
                                                                         U
                                                                         H
                                                                         •0
                                                                         0)
                                                                         >
                                                                         o

                                                                         CU
                                                                         1-1
                                                                   $1.00
                                                                         en
                                                                         o
                                                                         u
                                                                         CO
                                                                         c
                                                                   $0.50
2500
Figure 9.  Hypothetical Cost Function for  Street  Sweeping
                               C-55

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    range,  then street sweeping does not appear to be a very cost




    effective control option.




7)   A procedure for doing cost-effectiveness is available.  However,




    more performance data are needed before doing the analysis.
                                C-56

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References

1.  Castro Valley First Year Work Plan, 1979.

2.  Driscoll, E.D. and Assoc.,  "Combined Sewer Overflow Analysis Handbook
    for Use in 201 Facility Planning, Volume II:   Appendices".   Draft
    Report to USEPA, July 1981.

3.  Heaney, J.P. et al., "Nationwide Evaluation of Combined Sewer Overflows
    and Urban Stormwater Discharges, Volume II:  Cost Assessment and Impacts",
    EPA-600/2-77-064, Cincinnati, OH, 1977.

4.  Heaney, J.P. and S.J. Nix,  "Storm Water Management Model Level I—Compara-
    tive Evaluation of Storage-Treatment and Other Management Practices",
    EPA-600/2-77-083, Cincinnati, OH, 1977.

5.  Pitt, R., Unpublished Data,  1981.
                                     C-57

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            WATER QUALITY IMPROVEMENTS BY STORMWATER DETENTION








Introduction



     Detention is widely used in sanitary sewage treatment plants and



is particularly important in the field of stormwater flow and pollution


       19 20
control  '  .  This section describes the role of urban stormwater detention



facilities in water quality management, and the various methods to eval-



uate the pollutant control performance of the facility.  Most of the



material is taken directly from a synopsis of evaluation methods by Nix



et al23.



        A detention facility retains stormwater and attenuates peak



discharges.  In addition to these roles, detention provides some measure



of stormwater quality improvement.  However, because of the variable



nature of stormwater flows and pollutant loads, the mechanisms governing



the performance of detention facilities as pollution control devices are



not well understood.  The picture is further clouded by the lack of



useful performance data.  The poor condition of the data base is attribut-



able to the expense and time involved in collecting any type of stormwater



data.


                                                                        20
        At present, most detention basins are sized using a design storm



This concept has served well for many decades in the design of flow con-



trol structures.  However, design storms are difficult, if not impossible,



to determine for stormwater pollution control.  This difficulty is directly



related to the lack of historical data, the inability to measure benefits,



the unreliability of pollutant measurements, and the unclear relationship



between stormwater flows and pollutant loads.  A design storm must also be



accompanied by design "conditions" for the receiving water (and the addition-



al uncertainties and data requirements).  In general, the design storm is not





                                    C-58

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very useful when investigating pollution control capabilities.



        An alternative approach, advocated here, is to analyze the long-



term average or, in more detailed studies, a time series response.



Average performance is a useful preliminary indicator of a detention



basin's contribution to the abatement of total pollutant loads and to



provide initial design estimates.  The analysis of a time series of



facility performance parameters (e.g., suspended solids removal) provides



useful information lacking from a preliminary analysis; namely, the



abatement of extreme events (e.g., standards violations).  This information



is vital if the primary function of detention is to prevent "catastrophic"



events.  Unfortunately, such a time series analysis requires an extensive



pilot plant study and/or computer simulation. Pilot plant studies are time



consuming and expensive.  Computer simulation is less expensive in terms



of dollars and time but the simulation techniques are invariably open to



questions concerning their validity.



        Ideally, a problem should be approachable from several levels of



sophistication.  This philosophy is carried through the rest of the



section.  The evaluation techniques presented here range from simple



hand calculations for estimating average performance to sophisticated



computer models for time series analyses (see appendices).  Before discussing



the performance evaluation methods, a brief overview of the role and theory



of detention in stormwater quality management is in order.



Role of Detention in Stormwater Quality Control



        Detention is probably the most effective stormwater management


                                     19
tool available to the design engineer  .  Additionally, several states



and localities require detention.to manage stormwater flows from new develop-



ments.  This combination of technical/economic desirability and regulatory
                                     C-59

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pressure necessitates the development of analytical tools to determine the




pollution control capability of stormwater detention.




        Detention facilities provide flow or flood control by retaining,




buffering and attenuating flows.  These attributes also provide some




level of pollution control by detaining the flow long enough for removal




by physical and/or biochemical processes to occur.  Detention facilities




are often designed to serve the needs of flow control with pollution




control as a "side" benefit.  This approach seems reasonable because of




the more obvious destructive power of uncontrolled stormwater flows.




However, there are cases in which detention is provided primarily for




pollution control, e.g., Ottawa, Ontario, or to perform both functions,




e.g., throughout Florida.  In the case of a true dual-purpose facility,




the proper mixture of flow and pollution control is a complex economic




problem in which the benefits of each function must be evaluated and




balanced against each other.  This question will remain unanswered here




as the emphasis is on the evaluation of pollution control performance




and not the level of control desired.




        The mechanisms controlling pollutant removal in detention




facilities are complex and numerous.  Figure 1 summarizes the more




significant mechanisms.  Most of these factors can be related to the




concept of detention time.  Simply defined, detention time is the time a




parcel of water spends in the basin or pond.  More precise definitions are




presented in a later discussion.   The mechanisms shown in Figure 1 are each




affected by or affect detention time.  Particle settling is affected by




detention time as is biological stabilization.  Outlet structures can be




designed to achieve various detention times.  The inflow rates have a di-




rect bearing on detention times.  In short, detention time is the primary
                                      C-60

-------
n
                             bypass
                               inflow rote
precipitation
outflow rate/
outlet  structure
                         pollutant
                      characteristics.
                             artificial
                           drawdown
                            or cleaning
                                            basin geometry _>
                                            	Istabilizaji
                                                  i     	 r»c:iicr>DricInn /  ^»      s
                                   minimum
                                   pool
                                                               infiltration
              Figure 1.   Mechanisms Affecting  Pollutant Removal in Detention Facilities  (source: ref.  23)

-------
indicator of pollution control capability.  However, some problems are



encountered in precisely defining detention  time in the case of in-



termittent stormwater flows (see later discussion).



Predicting Stormwater Detention Pond Performance



        There are many methods for estimating the pollution control



capability of detention basins and ponds.  The range of sophistication



is wide but necessary to fit the various scenarios that might confront



an engineer.  Several methods are described in Appendix I.



        The primary indicator of pollution used throughout much of this



section is total suspended solids (TSS).  This constitutent is one of



the most commonly and reliably measured stormwater contaminants.  Addi-



tionally, many of the techniques only address suspended solids.  Five-



day biochemical oxygen demand (BOD-) is also a commonly, but much less



reliably, measured pollutant and is included where possible.  Many other



pollutants are measured but, because of the lack of data availability or



reliable test procedures, are omitted.  However, it may be possible to esti-



mate the effect on other pollutants by relating them to commonly measured



constituents (e.g., suspended solids).



Detention Time



        Detention time is the most important  single determinant of pollu-



tant control potential.  The concept of detention time is generally understood,



but its computation, especially in stormwater detention, is not always so clear.



The basic definition is simple; detention time is the length of time a parcel



of water spends in the basin or pond.  Detention time is easy to compute under



steady state conditions, i.e.,



        td = S/i                                                  (1)



where   t, = detention time, sec,
         a

                                 3
        S  = detention volume, ft , and


        _                          3

        q  = constant flow rate, ft /sec.





                                      C-62

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In completely-mixed units, t, represents the average detention time.  In plug-

flow units, t, is the actual time all parcels spend in the detention basin.

Unfortunately, a steady state condition is rarely found in a sanitary sewage

plant and is certainly improbable in stormwater detention facilities.  There-

fore, such a computational definition is of limited value.  Several analysts

have applied this definition to a design storm but this concept was discounted

earlier.

        For stormwater flows,  the theoretically ideal method is to

calculate the length of time each parcel of water spends in detention.

Obviously, this is not practical in real-world situations.  This problem

can be circumscribed by recognizing that factors such as outlet structure and

basin geometry control detention time and, fortunately, they are much easier

to measure or compute.  Varying these factors will produce different overall

control levels which can be measured directly.  However, it may be necessary

to compute detention time in a computer simulation model because of its pre-

dictive value.  These simulators allow the user to vary the factors control-
                   8 15 27
ling detention time '  '  .  This is often accomplished by modeling the de-

tention basin or pond as a plug-flow reactor.  Such a model simply queues

relatively small parcels or plugs (ideally, the parcel is infinitely small)
                 24
through the basin  .  In other words, the first parcel of water entering

the basin is the first parcel to leave.  Pollutants entering a basin

with a plug are assumed to remain with that plug.  The detention time

can be calculated for each plug by

        t,  = t, (2) - t, (1)                          (2)
         di    di       di
where t,  = detention time for plug or parcel i,


   t, (1) = point in time that plug i entered the basin, and

   t, (2) = point in time that plug i left the basin.



                                     C-63

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        Detention facilities may also be viewed as completely-mixed or


                       24
arbitrary-flow reactors  .  True values of detention time are difficult to



calculate under these assumptions.  In completely-mixed reactors the inflow



parcels and associated pollutants are completely intermixed with all other



parcels in the unit and, thus, lose their identity.  Arbitrary-flow reactors



are a blend of plug-flow and completely-mixed reactors.  Most detention units



can be thought of as plug flow or arbitrary flow reactors.  This is a realistic



assumption for stormwater detention facilities experiencing little or no turbu-



lence.  Completely-mixed stormwater detention is an anomaly when one consid-



ers that a major pollutant removal mechanism is particle settling.



        The purpose of this discussion is to provide some insight of the



role of detention time in the evaluation of detention basins and to serve as



a preface to a cautionary note.  It is often tempting to take the volume



of a detention basin or pond and divide it by some measure of flow and



call it "detention time".  This is probably due to the traditional



desire to define a. detention time.  But this is essentially impossible



in stormwater detention — there is no single value of detention time.



However, several variables are used in this section that appear to be



detention time (i.e., volume/annual flow) but, conceptually, they are



not.  They are only indicators of the relative detention capability


(and, in turn, pollution control capability).



Summary and Conclusions


        This section described the water quality aspects of stormwater de-



tention facilities and presented several methods for predicting removal



rates (see appendices).  Detention time is the primary determinant of pollu-



tant removal efficiency but its use is sometimes misunderstood.  Various



methods of estimating removal efficiency are presented.  Unfortunately, very



few field data are available at this time.  Thus, it is essential to perform



                                      C-64

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waste characterization and treatability studies on the local urban stormwater,




to aid the analysis.  These data can be used with the preliminary estimates




to guide the use of computer simulation in the evaluation of the continuous




operation of the detention facility.
                                     C-65

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Appendix I;  Basin Evaluation Methods



        This appendix describes various methods to estimate or evaluate



detention basin performance.  Examples are presented to illuminate the



procedures.



     The following information is common to all of the examples presented



in the detention basin performance summaries.  Data particular to a speci-



fic example are given in that example.



        A 600-acre (243 ha) drainage basin, located in a primarily resi-



dential area near Minneapolis, Minnesota has an average annual precipita-



tion of 26.0 in. (66.0 cm.).  The area has the following land use breakdown:



        Land Use         Area, acres (ha)         Percent of Total



        Residential          420 (170)                   70.0



        Commercial            30 (12)                     5.0



        Industrial            —



        Other (parks,        150 (61)                    25.0



          schools, etc.)
        Total                600 (243)                  100.0



The precipitation statistics for Minneapolis are given below.



                                                              Coefficient

        Parameter                     Mean                   of Variation



        Duration                D  =6.30 hr/event              v, = 1.14
                                 P                               d


        Intensity         I  =0.047 in/hr (0.119 cm/hr)        v  = 1.73



        Volume          V  =0.25 in/event (0.64 cm/event)      v  =1.56
                         P                                       r


        Intervent

          time                      A  = 84 hr                  v  = 1.02
                                     p                           
-------
variation, v  and v  , are assumed to equal v. and v , respectively.  The aver-




age annual runoff is (0.081 in/event)(104 events) or 8.42 in/yr  (21.39 cm/yr).




        A rectangular detention pond with a capacity of 10 acre-ft  (12335 m  )




is proposed to provide stonnwater quality control.  The pond's capacity is




measured to the bottom of a broad-crested weir (at a depth of 12 ft  (3.66 m).




The weir is 20 ft (6.10 m) long and rapidly discharges large flows.  The




total pond depth is 16 ft (4.88 m).  The length and width are 300 ft (91.4 m)




and 121 ft (36.9 m), respectively.  A 6-inch  (15.24 cm) orifice  is  located at




6 ft (1.83 m) for the slow release (over approximately one day)  of  the volume




between 6 ft (1.83 m) and 12 ft (3.66 m).  The volume held below the orifice




is discharged by evaporation and infiltration (over 6 days).  For simplicity,




the sides of the pond are assumed to be vertical.  The outflow is routed to




a nearby stream.
                                      C-67

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Method;  Brown's Trap Efficiency Curve (Source;  ref. 23)



Data Requirements:  1) Basin volume

                    2) Drainage area



Description;  An estimate of annual suspended solids removal can be taken from


                              2 27
an equation developed by Brown '  .  This equation relates sediment



trap efficiency to the detention pond volume-drainage area ratio.  Brown



based his equation on data collected from over 25 normally-ponded reservoirs.



The equation is
        R = 100
1 -
(I-A1)
                     11 + 0.1(S/A)
                     \            >


where   R = annual suspended solids removal, percent,



        S = pond volume, acre-ft, and



        A = drainage area, mi .



The resulting curve is shown in Figure I-A1.  The data used to develop



equation I-A1 are scattered; thus, the relationship is weak.  Also, the



S/A ratio provides little measure of the different hydrologic and soil



conditions found around the country.  Additionally, this equation applies



only to reservoirs where some water is held between storms.  Nevertheless,



with a minimal amount of information, a preliminary estimate is possible.



An example application is given below.  The same scenario presented earlier



is used.



        Brown's curve represents the crudest model of sediment removal.



It does not distinguish between the removal efficiencies of sands,



silts, or clays even though their detention times vary from minutes to



months.



Example;  The basin capacity and the drainage area are needed to use



Brown's equation.  The relationship is best used for ponded reservoirs with



relatively continuous inflows.  The estimated sediment or total suspended



solids removal is calculated below.  The 600-acre (243 ha) area comprises
                                      C-68

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                                                     200
        CAPACITY  WATERSHED RATIO, S/A, a ere-ft/mi
Figure  I-A1.  Brown's Trap Efficiency Curve  (source:  ref. 27)
                        C-69

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0.938 mi .   Using equation 14, the removal efficiency is
                                    1
        R = 100
1 -
                       1 + 0.1(10 acre-ft/0.938 mi'
          = 51.6%
                                      C-70

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Method;  Brune's Trap Efficiency Curves (Source:  ref. 23)

Data Requirements;  1)  Basin volume
                    2)  Basic knowledge physical characteristics of the
                        suspended solids
                    3)  Annual inflow to the basin

Description;  A more refined (relative to Brown's curve) set of curves was
                  36 77
developed by Brune ' '  .  These curves were based on data collected from

44 normally-ponded reservoirs and semi-dry reservoirs located in twenty

different states.  The curves are shown in Figure I-B1.  Rather than

basing sediment removal on the volume-drainage area ratio, Brune based

his curves on the volume-annual inflow ratio.  This ratio provides a

rough indicator of detention capability but cannot be defined as an aver-

age annual residence time.

        Brune's curves provide additional dimensions to the analysis;

i.e., a crude accounting of hydrologic conditions (annual inflow) and the

physical characteristics of the suspended solids load.  The upper curve in

Figure I-B1 represents a flow laden with coarse solids (i.e., sand).  The

lower curve represents a flow in which fine solids (i.e., clay) predominate.

The central curve represents a median of the two extremes.  Brune's curves

have been widely used in sediment basin design, but one caveat is necessary.

The data from semi-dry reservoirs did not correlate well with the curves

in Figure I-B1; hence, their usefulness is restricted to detention ponds.

However, Brune noted in his work that semi-dry reservoirs are likely to

achieve much lower removal efficiencies normally-ponded reservoirs.

Example;  Brune's curves (like Brown's curve) apply only to

normally-ponded reservoirs.  Again, for illustrative purposes, the

sediment or total suspended solids removal is estimated.  Assume that

the sediment is characterized by Brune's median curve.
                                      C-71

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o
I
NJ
            0.001    0.002
0.005   0.01     0.02        0.05     O.I     02        0.5



     CAPACITY-INFLOW RATIO,  acre~ft/acre-f1/yr
                                                                                     i.o
                                                                                                      5.0      10
                                     Figure I-B1.  Brune's Trap  Efficiency Curves  (source:  ref.  27)

-------
        To use Brune's curves, the capacity-annual inflow ratio must be



estimated.  The capacity is 10 acre-ft (1235 m ) and the annual inflow



is 8.42 in./yr (21.39 cm/yr) or 421.0 acre-ft (519354 m3/yr).   The



capacity-annual inflow ratio is —/01 n	j—,	 or 0.024 years.  From
  f    }                          421.0 acre-ft/yr            '


Figure I-B1 the corresponding annual removal percentage is approximately



65%.
                                      C-73

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Method;  Churchill's Trap Efficiency Curve  (Source:  ref.  23)

Data' Requirements;  1)  Average cross-sectional  area
                    2)  Basin volume
                    3)  Average runoff event  flow  rate
                                               r  -j  f\-t
Description;  The method proposed by Churchill ' *   relates  the per-

centage of sediment passing through a reservoir  to the  "sedimentation

index" of the reservoir.  The sedimentation index  is defined  as




                                     2
where   SI = sedimentation index, sec /ft,

         S = reservoir volume, ft ,

        0_ = average runoff event flow rate,  ft  /sec, and
         K
                                                               2
        A  = average cross-sectional area of  the reservoir, ft .

The average cross-sectional area is computed  by  dividing  the  reservoir

volume by the length of the reservoir (parallel  to the  flow).   If the

reservoir has an  irregular shape an average length should be  used.

Churchill's curve is shown in Figure I-C1.

Example:  To find the sedimentation index,  SI, the average cross-sectional

area, A , of the basin is required.  The length  of the  basin  is  300 feet

(91.4 m) and the width is 121 feet (36.9 m).   The  assumption  of  a rectangular
basin eases the computation of A  .
                         \  /   c
               10 acre-ftV / 43560  ft'
        Ac    \   300 ft   I' \  acre
             1452 ft2  (135 m2)
The average runoff event flow rate is 0.0.46  in/hr.   Converting this  value

     3
to ft /sec yields
                              /      \              //OC£C\  C  ^ \ /   U     \
        QD =  (0.0146 in./hr)  (T|^-|  (600 acres)  ' 4356°  ft  "    hr     '
              w.wj-tu j.u.,11..,  ,  12    ,  w«w «^*.CB/ ,   acre     ;i 3600 sec
                              \      /              \          / \

           =  8.8 ft3/sec  (0.25  m3/sec)
                                          3
The capacity  is 10 acre-feet or 435600 ft .   Thus, the  sedimentation

index is

                                      C-74

-------
n
i
PERCENT OF INCOMING SEDIMENT
PASSING THROUGH RESERVOIR, 100-F
_ 6
-oo
— «
	 1 II Mil
| 1 1 Illl
III Mil
| 1 1 I t III
1 i. i Inn
I i i | nil
1 i i hin
—
! i 1 1 nK

I04 I05 10s 107 I08 I09
QFHIMFMTATinM IMHFY HF RFC:FRV/niR QT c,^^2/^
                               Figure I-C1.  Churchill's Trap Efficiency Curve (source: ref. 27)

-------
       CT - .  435600 ft3 \ .   / 8.8 ft3/sec
       SI - I	r     I •   I         2

              8.8 ft /sec/    \ 1452 ft



          = 8.2 x 106 sec2/ft  (2.7 x 107 sec2/m)



From Figure I-C1 the corresponding total suspended solids removal is 100-



18% or 82%.
                                      C-76

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Method;  Statistical Moments Method, Sedimentation Tank (Source:  ref. 23)

Data Requirements;  1)  Surface area of the sedimentation tank
                    2)  Average runoff event flow rate
                    3)  Coefficient of variation for runoff event flow rate
                              25                 17
Description;  Small and DiToro   and Hydroscience   have developed a long-

term removal equation for stormwater treatment devices based on

assumed stochastic distributions of average event flow and pollutant

concentrations.  These distributions are based on storm relationships

shown in Figure I-D1.  Sedimentation tanks are viewed differently from

other detention facilities as they are not normally designed to provide

a significant level of storage.  However, this approach may be useful in

some cases. The pertinent equation is given as

     100-R = ^ J"J"[100-r(c,q)] c q p (c) p (q) dc dq         (I-D1)
               qc                  C     q

where R = long-term average pollutant removal, percent,

      c = runoff event concentration, Ib/acre-in.,

      q = runoff event flow rate, acre-in/hr,

 r(c,q) = percentage pollutant removal by treatment device as a function

          of c and q,

  p (c) = probability distribution function of average runoff event

          pollutant concentration,

  p (q) = probability distribution function of average event flow, and

     W  = average pollutant loading to treatment device for all events,

          Ib/hr.

The average flow for each runoff event, q, is assumed to be independent

of the average concentration and to have a mean of QR, a coefficient of

variation v , and a gamma probability distribution function.  The probabil-

ity distribution function of flow is given as

                          1C —1
                            * \
~
Q/
                                                                  (I-D2)
                  QR/   \r(K)
                                     C-77

-------
Ul
£E




O
 r VARIATION   WITHIN EVENTS
                        n
                         TIME
   VARIATION  BETWEEN  EVENTS
                         TIME
h-
cc.
s
n n

v
n


Figure  I-D1.  Representation of Storm Runoff Process (source: ref.  17)
                          C-78

-------
where  K = 1/v , and
              q

    F(K) = the gamma function with argument K.


The average event concentration, c, with mean C and coefficient of


variation v , is also assumed to be distributed according to the gamma


distribution function.


        If pollution removal is assumed to be a function of flow alone,


then equation I-D2 may be simplified to
         100-R = -f[100-r(q)]  q  p (q) dq            (I-D3)

                 T t *^                 *J
The usefulness of equation I-D3 for sedimentation tanks is enhanced by re-


quiring the average removal for each event to be described by

         / x      -bq/A
        r(q) = * *  ^  s                               (I_D4)


where a = coefficient, a <^ 100,


      b = coefficient, hr/in., and


     A  = surface area of sedimentation tank, acres.


The term q/A  can be viewed as an indicator of the "average" overflow
            s

rate or detention time for each event (recall earlier discussion).


Equation I-D4 requires that depth be relatively constant over the length


and width of the facility.  Several removal equations for suspended solids


are shown in Figure I-D2.


     Substituting equations I-D2 and I-D4 into equation I-D3, integrating


and solving for R, yields
        R = a
                    bQ
                1 + —
                      s J
K+l

                              (I-D5)
Equation I-D5 represents a long-term removal function relating pollutant


removal, R, to the average runoff event flow rate.  However, the value of R


                                     C-79

-------
n

oo
o
        100
        90
      -  80
<  7°


1  60
UJ
cc

CO  5°
g


d  40
CO

S  30
Q


I  20
CO

co   10


    0
0
THE CURVES REPORTED BY  IMHOFF AND FAIR^ASCE;1  AND SMITH 2(ftRE

    FOR  SANITARY SEWAGE.

THE CURVE BY LAGER etal.20IS FOR COMBINED SEWAGE.

THE COMPOSITE CURVE HAS  THE  FOLLOWING FUCTIONAL FORM'
                                                   IMHOFF AND FAIR
                                                                18
                          1000
2000
3000
                                            4000
                                                                                       5000
                                    OVERFLOW  RATE, q/A,_, gal/ft-day
                                                        s>
                        Figure I-D2.  Suspended Solids Removal by Detention/Sedimentation (source: ref, 9)

-------
estimated by equation I-D5 is probably conservative because of the additional




removal occuring between events.  Equations I-D3 through I-D5 assume that the




water level in the facility is constant during each storm and that the




detention facility remains full between storms (i.e., the level remains




at the bottom of an elevated outlet structure between storms).  In other




words, the basin is essentially a flow-through sedimentation tank and does




not provide any significant amount of storage.  Thus, this procedure is




probably only applicable to basins where the capacity is relatively small




when compared to most storm volumes.




        The advantage of such an approach is that local hydrologic factors




are included in the analysis.  Additionally, any pollutant may be investi-




gated.  The major drawbacks are obtaining the necessary statistics (i.e.,




v  and Q_.) and the size/flow restriction noted above.
 q      K



Example;  The average event runoff flow rate and the coefficient of




variation for the hypothetical drainage area are 0.0146 in/hr or 0.0371 cm/hr




and 1.73, respectively  (see earlier discussion).  Using the composite suspended




solids removal function given in Figure I-D2, the long-term average removal




percentage is computed  as follows:




       QD = (0.0146 in/hr) (ft/12 in)  (600 acres) (43560 ft2/acre)
        K



            (24 hr/d) (7.48 gal/ft3)




          = 57100000 gal/d




        K = 1/v  = 1/1.73 = 0.578

               q


        a = 80.0




        b = 0.000373 ft2-d/gal




       A  = 36300 ft2
        s
                                      C-81

-------
                                                       0.578 + 1
R = 80
          1 +
(0.000373 ft -d/gal) (57100000 gal/d)
       (0.578) (36300 ft2)
  - 68.7%
                              C-82

-------
Method:  Statistical Moments Method, Storage

Data Requirements:  1)  Set of runoff statistics (mean and coefficient of
                        variation of runoff event flow, volume, duration
                        and the time between storms)
                    2)  Basin volume
                    3)  Release rate

Description;  Hydroscience, Inc.   has developed a set of long-term per-

formance curves for storage basins operated with interevent drawdown

pumping.  A conceptual view of how such a storage/release configuration

operates is shown in Figure I-El.  From this figure and several assump-

tions, a set of curves relating the mean effective storage capacity, Vp,

to the maximum storage capacity, V_, and the interevent drawdown rate, ft,
                                  D

was developed.  These curves are shown in Figure I-E2.  Among the assump-

tions used to develop this relationship are the following:

     1)  The runoff flows, q, duration, d, and time between storms,  is calculated

                                      C-83

-------
as the by-passed load, divided by the total load:
               00    00
     fy - C   I     /       q(J - VE/q) pd(d) Pq(q)  dd dq          (I-E1)



            q = 0  d = V_/q
where fv = long-term fraction of pollutant load not captured,



       C = mean runoff pollutant concentration for all events, mass/volume



  P, (d) = probability distribution for runoff event duration, d,



  p  (q) = probability distribution for runoff event flow, q,



      QD = mean runoff flow for all events, volume/time, and
       K


      D_. = mean runoff event duration, time.
       K


Equation I-E1 was numerically integrated to obtain the curves shown in



Figure I-E3.  The fraction not captured, fv, is a function of the mean



effective storage capacity, V , and the coefficient of variation of the
                             E*


runoff volumes, v  .  Again the mean effective storage capacity, V , is
                 VK                                               c.


normalized over V  to enhance the applicability of the curves.  Note
                 K


that the runoff concentration is assumed to be independent of runoff



flow.  This creates a situation in which the runoff concentration is a



constant value, C, for all flows and, thus, first-flush effects are



ignored.  However, Hydroscience    developed a set of curves to account



for the first-flush effect.



     Unfortunately, this method only calculates the fraction of the



pollutant load "captured"  by the basin, i.e., the load that is not by-



passed for some period of time.  In order to account for the removal of



pollutants a relationship between long-term efficiency and an indicator



of detention ability is required.  The long-term efficiency is multiplied



by the fraction "captured" by the basin to determine the actual level of



pollution control.



                                      C-84

-------
VOLUME
                            T

                      !"•-
                                                       Ve
                                  STORM

                                    I
STORM

  2
TIME
         Legend



           V  = maximum storage capacity
            B


           V  = mean effective storage capacity
            £j


           V  = storm  1 volume



           ft  = drawdown rate between'Storms



           V  = available storage at the  start of a storm



           6  = time between storm midpoints
       Figure I-E1.  Conceptualization of Storage Operation (source: ref. 17)
                                   C-85

-------
                                                      14
     An approach similar to that used by Howard et al.   can be used with



this method to account for pollution reduction in storage, i.e.,



          R = a log (DT) + b                                        (I-E2)



where     R = long-term pollutant removal efficiency, 0 £ R £ 1.0



       a, b = coefficients, and



         DT = detention parameter, hr


                                                                 14
The definition of DT is purposely left unspecified.  Howard et al   recom-



mend letting DT = S/2ft where S is the basin volume in inches and ft is the



release or treatment rate in inches/hour.  However, other indicators of



detention ability are probably equally as valid (e.g., basin volume/average



inflow, basin volume/ total annual inflow, etc.).  The coefficients a and b



must be determined from an applicable data base such as a cross section of



basin data, by calibration against on-site data, or by calibration to the



results of a simulator that directly models pollutant removal (e.g. SWMM S/T



Block15) .



     Pollutant removal equations need not be limited to the type given by



equation I-E2.  Other forms are equally permissible as long as they can



be used to relate some indicator of detention time and long-term pollutant



removal.  One possible (and perhaps preferrable) alternative is
where     R = long-term pollutant removal efficiency, 0 ^ R >_ R



       R    = maximum efficiency, 0 > R    > 1,
        max                         —  max —


          K = coefficient, 1/hr, and



         DT = detention parameter, hr.



The reader is cautioned that the results from batch settling tests are not



directly suitable to find values for the coefficients in equations I-E2 or



I-E3.  In these applications, the critical variable is the elapsed settling



time, t ,.  The parameter DT is only an indicator of the detention ability



                                      C-86

-------
UJ
  UJ
  UJ
i.O
2.0
                     3.0
                                                4.0
                       .[STORAGE. VOLUME (EMPTY)
                           MEAN RUNOFF VOLUME
   Figure I-E2.   Determination  of  the Mean Effective Storage Capacity, V

                 (source:  ref.  17)
                                  C-87

-------
          0.5
1.0
               VR
 1,5 ' .  2.0   2.5    3.0    3.5    4.0

EFFECTIVE STORAGE CAPACITY
  MEAN RUNOFF  VOLUME
4.3
5.0
Figure I-E3.  Determination of  the Long-Term Fraction of the Pollutant
              Load Not Captured by Storage,  f  (source:  ref. 17)
                                 C-88

-------
of the basin.  On the other hand, t, is a real-time measure limited to ex-




perimental work and simulators capable of tracking the detention time of




each water parcel as it passes through a detention basin.




Example:   None
                                      C-89

-------
Method:  Statistical Analysis Method (Source: ref. 14)

Data Requirements:  1)  Set of runoff statistics
                    2)  Basin capacity
                    3)  Treatment plant or release rate

Description;  The purpose of the statistical analysis method is to obtain

closed form expressions for the probability distributions of runoff, overflow

and pollution events - expressions which reflect the natural physical proc-

cesses in the watershed and the effect of man-made facilities and operations.

These results can then be used in planning control strategies.

     To accomplish this, the watershed has to be represented by a very

simple model.  Storm events are defined, and the rainfall data are analyzed

to obtain the statistics of rainfall probability distributions.  Using

these distributions and a watershed model, probability distributions of

runoff and pollution events are then derived.  These distributions form the

basis for determining the runoff and pollution control provided by combina-

tions of storage and treatment capacities.

     The watershed and facilities are shown schematically in Figure I-El.

Rainfall is the input to the watershed.  This input is transformed into run-

off, whose temporal behavior depends on that of the rainfall and on the stor-

age and conveyance characteristics of the watershed.  The runoff picks up

pollution from the watershed and flows into the man-made reservoir.  Water

is released from the reservoir to the treatment plant, and the treated outflow

is discharged into the receiving waters.  When the reservoir cannot contain

all the runoff, the remainder spills into the receiving waters without going

through the treatment plant.  Water can also be released after detention in

storage into the receiving waters without passing through treatment.  This

allows the operator to prepare some empty storage when he expects the next

storm, releasing into the receiving waters runoff which was already allowed

to settle in the reservoir and trapping the first flush of the next storm.

                                      C-90

-------
     The mathematical method is based on the following propositions and




assumptions:



     (1)  Runoff is generated from the rainfall by first subtracting the



          depression storage, s,, and then multiplying the remaining



          effective precipitation by the runoff coefficient, .



     (2)  The concentration of pollution in the runoff waters is constant,



          independent of the time between storms, rainfall intensity, or



          time during the storm.  Any specified single pollutant (e.g.



          suspended solids) can be considered.



     (3)  The treatment plant operates at a constant rate, ft (in inches/



          hr), as long as water is in the reservoir.  This treatment rate



          is assigned to storm runoff only, i.e., it is the capacity of



          the sewage treatment plant above that needed to treat dry weath-



          er flows as it is a separate wet-weather plant.



     (4)  The efficiency of the treatment plant, n0, is constant.
                                                  uu


     (5)  The storage reservoir has a treatment efficiency, n  , which is
                                                             O


          due to the residence time of water in it.  This efficiency is



          estimated as



               n  = a log (DT) + b,            RT <_ RTMIN        (I-F1)
                s


          where (a) and (b) are empirically determined coefficients and



          RTMIN is some reasonable minimum value of DT above which



          equation I-F1 is valid.  The value of DT, the detention



          parameter, is estimated as S/2ft where S is the basin



          capacity (in inches).



     (6)  The bypass overflow receives no treatment, and therefore enters



          into the receiving waters with the original pollutant concentra-



          tion.



     (7)  Runoff enters the reservoir at a constant rate for the approxi-




                                      C-91

-------
                                      RAIHFAU,
                                 WATERSHED
                                      RUNOFF
                          TREATMENT
                           PLANT
                          STORAGE
                          OVEHFLOW
BYPASS
OVERFLOW
                              RECEIVING HATERS
.Figure I-F1.
Schematic Representation  of  the System Used by  the
Statistical Analysis Method  (source:  ref. 14)
                                         C-92

-------
          mate duration of the rainfall, i.e. the temporal distribution of




          inflow to the reservoir is not affected by routing on the water-




          shed or in the pipes.




     (8)  The reservoir is assumed to be full at the end of the previous




          storm.




Example;  None
                                       C-93

-------
Method;  Corps of Engineer's STORM model  (Source  : ref. 16)

Data Requirements;  1)  Long-term hourly  rainfall record
                    2)  Drainage area characteristics  (imperviousness,
                         depression storage)
                    3)  Basin volume
                    4)  Treatment plant or release rate

Description;  Figure I-G1 shows a schematic representation of the seven

storm water elements modeled by STORM.  In this approach, rainfall washes

dust and dirt and the associated pollutants off the watershed.  The re-

sulting runoff is routed to the treatment-storage facilities where

runoff less than or equal to the treatment rate is treated and released.

Runoff exceeding the capacity of the treatment plant is stored for treatment

at a later time.  If storage.is exceeded, the untreated excess is wasted

through overflow directly into the receiving waters.  The magnitude and

frequency of these overflows are often important in a storm water study.

STORM provides statistical information on washoff, as well as overflows.

The quantity, quality, and number of overflows are functions of hydrologic

characteristics, land use, treatment rate, and storage capacity.

     Computations of treatment, storage,  and overflow are accomplished on

an hourly basis throughout the rainfall/snowmelt record.  Periods of no

rain are skipped.  The number of dry hours is used for various purposes

including recovery of soil moisture storage capability.  Every hour in

which runoff (may include dry-weather flow) occurs, the treatment facili-

ties are utilized to treat as much runoff as possible.  When the runoff

rate exceeds the treatment rate, storage  is utilized to contain the

runoff.  When runoff is less than the treatment rate, the excess treatment

rate is utilized to diminish the storage  level.  If the storage capacity

is exceeded, all excess runoff is considered overflow and does not pass through

the storage facility.  This overflow is lost from the system and cannot be

treated later.  While the storm runoff is in storage its age is increasing.

                                     C-94

-------
Various methods of aging are used including average, first-in:  last-out,



first-in: first out, or others, depending on the inlet and outlet configurations



of the storage reservoir.  STORM does not compute the amount of pollutant



reductions due to settlement of solids while in storage.


                                                      14
     An approach similar to that used by Howard et al.   can be used with



STORM to account for pollution reduction in storage, i.e.,



          R = a log (DT) + b                                        (I-G1)



where     R = long-term pollutant removal efficiency, 0 >_ R >_ 1.0



       a, b = coefficients, and



         DT = detention parameter, hr


                                                                  14
The definition of DT is purposely left unspecified.  Howard et al.   recom-



mend letting DT = S/2T where S is the basin volume in inches and T is the



release or treatment rate in inches/hour.  However, other indicators of



detention ability are probably equally valid (e.g., basin volume/average



inflow, basin volume/total annual inflow, etc.).  The coefficients s. and b



must be determined from an applicable data base such as a cross section



of basin data, by calibration against on-site data, or by calibration to



the results of a simulator that directly models pollutant removal (e.g.,



SWMM S/T Block15).



     Pollutant removal equations need not be limited to the type given by



equation I-G1.  Other forms are equally permissible as long as they can be



used to relate some indicator of detention time to long-term pollutant



removal.  One possible (and perhaps preferable) alternative is



          R = R   (1 - e"k(DT))                                     (I-G2)
               max


where     R = long-term pollutant removal efficiency, 0 <_ R <_ R
                                                            ~~*


       R    = maximum efficiency, 0 < R    < 1,
        max                         — max —


          K = coefficient, 1/hr, and



         DT = detention parameter, hr.



                                      C-95

-------
n
VO
                          //  '  '  '  /  '  '  '
                          'II '     /    /
                         /'/'/  / / '  / '  /   RAINFALL/SNOWMELT
                                                                 STORAGE
                                                   DRY WEATHER
                                                   FLOW
                                                SURFACE
                                                RUNOFF
POLLUTANT
ACCUMULATION
                                      POLLUTANT
                                     WASHOFF AND
                                     SOIL EROSION
                                             OVERFLOW
                                                                            TREATMENT
               Figure I-G1.  Major Processes Modeled  by STORM (source:  ref. 16)

-------
The reader is cautioned that the results from batch settling tests are




not directly suitable to find values for the coefficients in equations




I-G1 and I-G2.  In these applications, the critical variable is the




elasped settling time, t,.  The parameter DT is only an indicator of the




detention ability of the basin.  On the other hand, t, is a real-time




measure limited to experimental work and simulators capable of tracking




the detention time of each water parcel as it passes through a detention




basin.




     The long-term pollutant removal efficiency is multiplied by the




estimate of pollutant "capture" provided by the model to determine the




overall level of pollution control.  Pollutant capture is defined as the




fraction (on an annual basis) of the pollutant load passing through the




storage-treatment system.




Example;  None
                                      C-97

-------
Method:  SWMM Storage/Treatment Block (Source:  ref. 23 and ref. 15)

Data Requirements;  1)  Basin geometry and outlet hydraulics
                    2)  Pollutant removal equation or particle size distribution
                    3)  Flow and pollutant concentration time series
                        (from measurements and/or another simulator)
                    4)  Evaporation rates

Description:  The University of Florida   has developed the Storage/Treatment

(S/T) Block as part of the extensive EPA Storm Water Management Model

(SWMM).  The S/T Block is a flexible simulator capable of modeling

several storage/treatment units, including detention facilities.  The

model has several advantages, among them:

        1)     the ability to model a wide variety of detention facility

               geometries and outlet structures;

        2)     sludge accounting;

        3)     the capability for dry-weather drawdown;

        4)     it is readily interfaced with the other blocks of SWMM

               (which have the ability to simulate stormwater discharges

               from a variety of drainage areas) ;

        5)     pollutants may be characterized by particle size/specific

               gravity distributions;

        6)     a wide variety of time-varying pollutant removal equations

               may be used;

        7)     any pollutant may be simulated; and

        8)     it is the most versatile model available.

The model lacks the ability, however, to model the resuspension of

settled particles.  Basins may be modeled as completely-mixed or plug

flow reactors:  intermediate (arbitrary flow) modes are not available.

A detailed description of the SWMM Storage/Treatment Block is given by

Huber et al.
                                      C-98

-------
     For complete mixing, the concentration of the pollutant in the unit

is assumed to be equal to the effluent concentration.  The mass balance

equation for the assumed well-mixed, variable-volume reservoir shown in

Figure I-H1 is 22:

          ^T^-- Kt) CX(t) - 0(t) C(t) - K C(t) V(t)               (

where     V = reservoir volume, ft  ,

         C  = influent pollutant concentration, mg/1,

          C = effluent and reservoir pollutant concentration, mg/1,
                             3
          I = inflow rate, ft /sec,
                              3
          0 = outflow rate, ft /sec,

          t = time, sec, and

          K = decay coefficient, sec

Equation I-H1 is very difficult to work with directly.  It may be approxi-

mated by writing the mass balance equation for the pollutant over the in-

terval, At:

Change in        Mass entering      Mass leaving       Decay during
mass in basin =  during At      -   during At     -    At

              Cl h + C2 Z2       Cl°l + C2°2         C1V1 + C2V2
C2V2 - C^ =  L  L 2     L  At -  ± ± 2  2 2  At - K  L L 2  Z 2 At    (I

where subscripts 1 and 2 refer to the beginning and end of the time step,

respectively.
                                                            27
     From a separate flow-routing procedure (the Puls method  ), I.. , I_, 0.. ,

0?, V1, and V_ are known.  The concentration in the reservoir at the beginning

of the time step, C.. , and the influent concentrations, C^ and C_ are also

known as are the decay rate, K, and the time step, At.  Thus, the only

unknown, the concentration at the end of the time step, C_, can be found di-
                                      C-99

-------
          I(t),(T(tJ
0(t),C (t)
                                           /\
                     V
                            V(t),C(t)
Figure I-H1.  Well-Mixed, Variable-Volume Reservoir (source: ref.  24)
                                C-100

-------
            Table I-H1.  Detention Facility Performance, S/T Block  (source: ref.  23)
UNIT  PERFORMANCE SUMMARIES FOR YEAR  1971
******** SUMMARY FOR  UNIT «   I.
          DETENTION DASIN
                         ********
INFLOW, TOT
BYPASS
INFLOW, TRT
OUTFLOW
RESIDUALS
REMAINING
EVAP.  LOSS   0. 3193E+05

0.
0.
0.
0.
0.
0.
FLOW
(CF)
1675£+0a
0
1675E+OQ
16DOE+03
0
2189E+06
FLOW
'•/.- TOT y. TRT
0.
100.
98.
0.
1.
scoomoo
98.
O.
1.
inonc
SUS. SOLIDS
(LBS)
oooooo
3571E+06
0
3571E+06
1475E+06
0
2094E+06
SUS. SOLIDS
•/: TOT •/. TRT
0.
10O.
41.
O.
58.
0
0
3
0
6
41. 3
0. 0
«O L.
W_r. O
OOOOOO
BOD
(LOS)
54Q4E+05
O
5404E+05
36OOE+O5
0
1BO2E+05
BOD
V: TOT •/: TRT
O.
10O.
66.
0.
33.
0
0
6
0
3
66.
O.
33.
6
O
3
o. a
0. 2

-------
o
NJ
    O
   Ijj
   <
   o:
   3
         50
        40
         20
         10
          0
              HYPOTHETICAL DETENTION BASIN
                  MINNEAPOLIS, MINNESOTA
                 STORM OF AUGUST 31, 1971
          DEPTH
          INFLOW
         -OUTFLOW
                                     15
                                              10
                                                 X

                                                 uj
                                                 Q
                                    O
          I2:00om   6:00am    I2=00pm    GOOpm

           K	AUGUST 31,1971	
12'00am
 &00am    !2OOpm    6:00pm

-SEPTEMBER  1,197!	
I2=00om
      Figure 1-112.   Detention Facility Quantity Performance, Storm of August 31, 1971,  S/T Block (source: ref.  23)

-------
rectly by rearranging equation I-H2 to yield




                 (C1 h + C2 V        Cl°l        K C1V1
          C^ +                 At  -        At  -         At

           1 L          2                2            2

     C  = 	:r—	5	        (I-H3)

      2               V,(l+^)  +  ^2 At

                                       2



Equation I-H3 is the basis for the complete mixing model of pollutant



routing through a detention unit.



     Equations I-H1, I-H2, and I-H3 assume that pollutants are removed at



a rate proportional to the concentration present in the unit.  In other



words, a first-order reaction is assumed.  The coefficient K is the rate



constant — it represents the fraction of pollutant removed per unit of



time.  Thus, the product of K and At represents the fraction removed



during a time step, R.  The user controls the value of R through the use



of a user-supplied removal equation (see Equation I-H6 and accompanying



discussion).



     Removed pollutant quantities are not allowed to accumulate in a



completely-mixed detention unit.  Strictly, pollutants cannot settle



under such conditions.  All pollutant removal is assumed to occur by



other means, such as biological decomposition.  Several processes such as



flocculation and rapid-mix chlorination are essentially completely-mixed



detention units.



     If the user selects the plug flow option, the inflow during each



time step, herein called a plug, is labeled and queued through the



detention unit.  Transfer of pollutants between plugs is not permitted.



The outflow for any time step is comprised of the oldest plugs, and/or



fractions thereof, present in the unit.  This is accomplished by satisfying



continuity for the present outflow volume (calculated by the Puls flow-


                 27
routing procedure  ):





                                     C-103

-------
   10,000
Q  8,OOO

O
_J

CO
9   6,000
-I
o
CO
Q
LU
Q-
CO
ID
CO
     4,000
2,000
                                                                  HYPOTHETICAL  DETENTION  BASIN
                                                                       MINNEAPOLIS. MINNESOTA

                                                                     STORM OF AUGUST 31, 1971
                                                         INFLOW

                                                         OUTFLOW
                                                  "* *** ~ ~t ^ *"•-•- *f - -, _    ' |  ^^      	|
         12^00 orn   G^OOom    !2'-OOpm    6=00 pm

            	-AUGUST  31, 1971	
                                                         6--OOom    1200pm     &00pm

                                                         -SEPTEMBER  1,1971	
 Figure  1-113.  Detention Facility Quality Performance, Storm of August 31,  1971, S/T Block (source; ref. 23)

-------
              V  '  £   " v
                           °
                                                                   3
where     V  = volume leaving unit during the present time step, ft ,


          V. = volume entering unit during the j   time step (plug j),


               ft3,


          f. = fraction of plug k that must leave the unit to satisfy


               continuity with V , 0 4 f. 4 1,


          JP = time step number of the oldest plug in the unit, and


          LP = time step number of the youngest plug required to


               satisfy continuity with V .


Removal equations are specified by the user (see later discussion) and, in most


cases, should be written as a function of detention time (along with other


possible parameters).  The detention time for each plug j is calculated as


          (td). = (KKDT - j) At                              (I-H5)


where KKDT = present time step number.


     Removal of any pollutant may be simulated as a function of detention


time, the time step size, its influent concentration, the removal fractions


of pollutants, and/or the influent concentrations of other pollutants.  This


selection is left to the user but there are some restrictions (depending


on the basin type).  A single, flexible equation is provided by the


program to construct the desired removal equation:

  R__I      r    i   ^ i  _  _  r_i   ^  i _  	r_i	  O
  — I
                                            S9   a!0
where     x. = removal equation variables,


          a . = coefficients , and


          R = removal fraction, 0 <_ R <_ 1.0.
                                     C-105

-------
The user assigns the removal equation variables, x., to specific
program variables (detention time, flow rate, etc.).  If an equation
variable is not assigned it is set equal to 1.0 for the duration of the
simulation.  The values of the coefficients, a., are directly specified
by the users.  There is considerable flexibility contained in equation
I-H6 and, with a judicious selection of coefficients and assignment of
variables, the user probably can create the desired equation.  An example
is given below.
     An earlier version of the Storage/Treatment Block employed the
                                                                       12
following removal equation for suspended solids in a sedimentation tank  :

          RSS = Rmax(1 - e"Ktd)                 (I'H7)
where     Rc  = suspended solids removal fraction, 0 4 Rcc 4 R   ,
           o o                                           bo    max
         R    = maximum removal fraction,
          max
           t, = detention time, sec, and
            K = decay coefficient, sec
This same equation could be built from equation I-H6 by setting a.. 9 = R   ,
                                                                 j_^    Tnflx
a.., = -R   , a, = -K, a., = 1.0, and letting x, = detention time, t,.
All other coefficients, a., would equal zero.
     Treatability studies can help determine the value of decay coeffi-
cients (See Appendix II).  Ideally, there would also be some flow and
pollutant concentration measurements (for the influent and effluent,
concurrently) for an adequate calibration.  However, if treatability data
are the only source of performance data, the model could probably generate
a reasonable estimate of long-term performance.
Example:  The Storage/Treatment (S/T) Block of the Storm Water
Management Model was used to simulate the hypothetical detention facility
described earlier.   A year of flow and pollutant concentration data were
generated using the Corps of Engineers' STORM model and linked to the S/T
                                     C-106

-------
Block through an interfacing program.  These data were generated from the



land use information provided in the general example description and the



Minneapolis precipitation record for 1971.  Based on a frequency analysis of



25 years of precipitation records, Heaney et al.   selected 1971 as a fairly



typical year for Minneapolis.  The basin was modeled as a plug-flow unit and



a relationship identical to equation I-H7 was used to remove suspended solids



and BODC.  The value of R    was set at 0.65 and 0.35 for suspended solids
       5                 max                                 r


and BOD,., respectively, and the value of K equalled 0.0003 sec   in both



cases.  The results are summarized in Table I-H1.  The suspended solids



removal is 58.7 percent and the BOD,- removal is 33.4 percent.



     A simulator provides an extra benefit in that specific periods can be



investigated in more detail.  The behavior of the facility during the storm



of August 31, 1971 is shown in Figure I-H2.  The total rainfall for this



storm was 1.19 in. (3.02 cm).  A scan of the results shows the expected re-



sponse.  The peak flows are substantially reduced and discharged over a



significantly longer period than that of the inflows.  In this particular



case, the discharges are very high when the water depth in the basin ex-



ceeds 12 ft (the depth at the bottom of the weir) and very low between



6 ft and 12 ft (orifice discharge).  A substantial reduction in the



suspended solids loading is also evident.
                                      C-107

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Method:  Other Simulation Methods (Source: ref. 23)
Data Requirements;  Variable; generally requires basin geometry, outlet
                    structure, pollutant removal coefficients and inflow
                    time series.
                                                  8
Description;  In a report by the City of Milwaukee  concerning the design of
the Humboldt Avenue detention basin, a simple model was developed to aid
in the analysis.  In this model, the basin is treated as a constant-
volume, plug-flow reactor and pollutants are removed as a function of
detention time (i.e., the length of time a plug of water remains in the
basin).  No provisions are made for solids characteristics (i.e., particle
size distribution), resuspension of settled material, sludge build-up or
varying outlet structures.  Despite its simplicity, the model admirably
performed the required tasks.
                                                      28
        A more advanced model developed by Ward et al.   was given the
acronym DEPOSITS.  It is designed to simulate sediment detention basins
but is readily adaptable to urban stormwater detention facilities.
Again, the detention facility is modeled as a plug-flow reactor.  In
this case, sediment is removed by simulating the settling of
particles and a particle size/specific gravity distribution is required.
In contrast to the Milwaukee model,  DEPOSITS is capable of simulating
the facility as a variable surface area and volume unit.  The model also
accounts for the effects of sediment (sludge) build-up.  It is not in-
tended for long-term simulations.
              22
        Medina   constructed a detention facility model by solving the
differential equations governing the movement of flow and pollutants
through well-mixed detention basins.  The solutions, containing complex
integrals, are directly useable if simple forcing functions (inflow
hydrographs and pollutographs) are assumed.  However, these forcing
functions are rarely simple and, in fact, contain a substantial random
                                     C-108

-------
element.  Thus, direct solutions are nearly impossible to achieve.  This




difficulty is overcome by evaluating the solution at discrete intervals




and assuming a constant forcing function over each interval.  This method




is applicable to constant and variable volume facilities.  Unfortunately,




the model is limited to a linear relationship between volume and outflow.
                                      C-109

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Appendix II;  Treatability Studies for Detention Basins



     Several NURP studies are evaluating the removal efficiencies of



stormwater detention ponds.  Data on the performance of these ponds are


                                29
very scarce.  Whipple and Hunter   have examined the settleability



of urban runoff pollution.  Their data will be used to describe a rela-



tively general procedure for summarizing the results of a treatability



study.  Figure II-l shows their settleability data for hydrocarbons.  The



usual assumption in environmental engineering is that pollutant removal



follows first-order kinetics.  If this is the case then the equation for



hydrocarbon removal can be represented by



               C/CQ - e"kt                                       (II-l)



where     c = hydrocarbon concentration at- any time t, mg/1,



         c  = initial hydrocarbon concentration, mg/1,



          t = detention time, hr, and



          k = rate constant, hr



Taking the logarithm of equation (1) yields



               ln(c/cQ) = -kt                                    (II-2)



Thus, a plot of the data on semi-log paper should yield a straight line



with a slope of -k.  Unfortunately, the data do not plot as a straight



line on semi-log paper (see Figure II-2) indicating that the assumption of



first-order kinetics, in this case, is inappropriate.  A primary reason for



the popularity of assuming first-order kinetics is that the resulting solution



is so simple.  Removal efficiencies are independent of initial concentrations.



However, first-order kinetics may provide a reasonable approximation if the



range of times is relatively short.  For example, first-order kinetics



can be assumed to hold for the hydrocarbon data as long as the detention



times are less than about eight hours (see Figure II-2).   One could next



try second-order kinetics, or third order, or zero order.  Fortunately,



                                      C-110

-------
mg/ /

 3.0,-
  2.0
  1.0-
                                                      20          25

                                                   TIME (Hours)
	j	
 30
	:!	

 35
40
          Figure II-l.  Settleability of Hydrocarbons, Lawrcnccville Shopping Center (source: ref. 28)

-------
iff 10,0
                                          Figure II-2.  Plot of Hydrocarbon Data on

                                                       on Semi-Log Paper
                          .'I  ..
                         -14-fl-
                          I r I
  o   "	"~  	"
                              10                     20
                                Detention  t'ime,  hours
e-ii2

-------
a more general approach exists wherein the order can assume non-integer



values.



     The rate of reaction and concentration of reactant can be related



as follows:



                - £ = r = k cn                                  (H-3)



where          r = reaction rate,



               k = rate constant,



               c = concentration of reactant, and



               n = reaction order.



Using equation II-3, the reaction order can be found by plotting reaction



rate, r = dc/dt, versus concentration, c, as shown in Figure II-3.  Techni-



cally, the above procedure is called the differential method for deter-



mining the reaction order for isothermal irreversible reactions in a


                                                        21      12
perfectly mixed, constant volume reactor (see Levenspiel  , Hill  ,


                   13             4
Holland and Anthony  , and/or Butt  for details).  The expression for the



proportion remaining can be found for any n by solving



               r = -dc/dt = k cn                                 (II-4)



Integrating equation I1-4 yields
               C/CQ = [1 +  (n-Dc^"1 kt]1'11    n j -1            (II-5)



For the hydrocarbon data, k = 0.037, n = 1.90 (see Figure II-3),  and CQ



2.8 mg/1.  Substituting into equation II-5 yields
simplifying,
               c/c  -  [1 +  (1.90-1)2.8(1-9°"1)  (.037)t]1'1'90, or
                  o
               c/c  =  [1 +  .0842t]~1'11                           (II-6)
                  o
Equation II-6 can be spot checked by trying a few trial values of t.
           t.-hr.


             5              0.62                0.68

            15              0.36                0.40

            25              0.30                0.28




                                      C-113

-------
   1.0
                                                                  Si
                                                                           I-
                                                                              5
                                                                           -FTI-TTrlT
                                                                              m
                                                                  ffn
                                                    55rffi
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                     h
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                  TtT"
                  -H-

                        fl

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                                                                            ^IH-!;
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                                                                                      rrrr
                                                                                           rti I-
                                                                                           ITI-I
                                                                                                -TIT;.
                                                                            :rrj-.r.|--pp
                                                                                          .! J
                                                                                                      ^i^-i-!--
        =l:
0.001
        TTiT
        •rrrr

       ~n"l"
       -rhT
        TrFT
         rrrr
         'TIT
                       I
                                                Tl"
                                                          .J

                                                          fflffi
                                                 ffl
                                                                        x
                                                                        .-i-H ii.
                                                                        r^m
                                                                                            -H-t-r
                                                                                            -rnT
                                                               Hi'
                                                                                          r
                                                •M-rT|ifEt
                                                rrrnTrii uji nn
                                                TTTrniTr THThni
                                                                                            -rrn
                                                                                            TIT1
                                                                                                 -r-
0.1
                           45678
                                       9

                                       1.0
                                                         3    45670
                                                                            0
                                                                                                   5   ii  7  b  'j \f
                                      Concentration,  c,  mg/1
                     Figure  II-3.  Determination of Reaction Order for  Hydrocarbons



                                                    C-114

-------
The equation is on the high side in the lower range of time and is a
                            • ;  .                 ••-'.

little high for larger times.


     Using equation II-5 as a general equation, the results from treata-


bility studies can be expressed in terms of three parameters, initial


concentration, c , the reaction order, n, and the reaction coefficient,


k.  Admittedly, equation II-5 only applies for a relatively restrictive


case of a constant volume, isothermal, completely mixed batch reactor in


which all constituents are assumed to react independently.  Nevertheless,


it is much better than making the potentially unrealistic assumption that


first-order kinetics apply.
                                      C-115

-------
References
 1.  American Society of Civil Engineers,  "Sewage Treatment Plant Design,"
        Manual of Practice No. 8, ASCE, 1960.

 2.  Brown, C.B., "The Control of Reservoir Silting," Misc. Pub.  521, U.S.
        Department of Agriculture, Washington, D.C., 1943.

 3.  Brune, G.M., "Trap Efficiency of Reservoirs," Trans.  American
        Geophysical Union, Vol. 34, No. 3,  1953,  pp. 407-418.

 4.  Butt, J.B.,  Reaction Kinetics and Reactor Design, Prentice-Hall,
        Englewood Cliff, New Jersey, 1980.

 5.  Camp, T.R.,  "Sedimentation and the Design of Settling Tanks," Proc.
        American Society of Civil Engineers, Vol. Ill, 1946, pp.  895-936.

 6.  Chen, C., "Design of Sediment Retention Basins," Proc. of the National
        Symposium on Urban Hydrology and Sediment Control,  University of
        Kentucky, Lexington, Kentucky, July 28-31, 1975.

 7.  Churchill, M.A., "Analysis and Use of Reservoir Sedimentation Data"
        by L.C. Gottschalk, Proc. Federal Inter-Agency Sedimentation
        Conference, Washington, D.C., 1948.

 8.  Consoer, Townsend, and Associates for the City of Milwaukee, Wisconsin,
        "Detention Tank for Combined Sewer Overflow - Milwaukee,  Wisconsin,
        Demonstration Project," EPA-600/2-75-071, U.S. Environmental Pro-
        tection Agency, December 1975.

 9.  Drehwing, F.J. et al., "Combined Sewer Overflow Abatement Program,
        Rochester, N.Y. - Volume II.  Pilot Plant Evaluations,"
        EPA-600/2-79-031b, U.S. Environmental Protection Agency,  Cincinnati,
        Ohio, July 1979.

10.  Fair, M.F.,  Geyer, J.C., and Okun, D.A.,  Water And Wastewater
        Engineering, John Wiley and Sons,  Inc., New York,  New York,
        1968.

11.  Heaney, J.P. et al., "Nationwide Evaluation  of Combined Sewer
        Overflows and Urban Stormwater Discharges:  Volume II, Cost
        Assessment," EPA-600/2-77-064, U.S. Environmental Protection
        Agency, Cincinnati, Ohio, March 1977.

12.  Hill, C.G.,  An Introduction to Chemical Engineering Kinetics and
        Reactor Design, John Wiley and Sons, Inc., New York, New  York,
        1977.

13.  Holland, C.D., and R.G. Anthony, Fundamentals of Chemical Reaction
        Engineering, Prentice-Hall, Englewood Cliffs, New Jersey  1979.
                                     C-116

-------
14.  Howard, C.D.D.,  Flatt, P.E.,  and Shamir,  U.,  "Storm and Combined
        Sewer Storage Treatment Theory Compared to Computer Simulation",
        Grant No.  R-805019, U.S. Environmental Protection Agency,  Cinnci-
        nati, Ohio, October 1979.

15.  Huber, W.C.,  Heaney, J.P., Nix,  S.J.,  Dickinson,  R.E., and Polmann,  D.J.,
        "Stormwater Management Model  User's Manual—Version III",  Project
        No. CR-805664, U.S. Environmental Protection Agency, Cincinnati,
        Ohio, November 1981.

16.  Hydrologic Engineering Center, Corps of Engineers,  "Urban Storm-
        water Runoff:  STORM,"  Generalized Computer Program
        723-S8-L2520, Hydrologic Engineering Center, Corps of Engineers,
        Davis, California, August 1977.

17.  Hydroscience, Inc.,  "A Statistical Method for the Assessment  of
        Urban Stormwater," EPA-440/3-79-023, U.S.  Environmental
        Protection Agency, Washington, D.C., May 1979.

18.  Imhoff, K. and Fair, G.M., Sewage Treatment,  John Wiley and Sons,  Inc.,
        New York,  1941.

19.  Kamedulski, G.E. and McCuen,  R.H..  "Evaluation of Alternative
        Stormwater Detention Policies,"  Journal of the Water Resources
        Planning and Management Division, ASCE, Vol. 105, No. WR2,
        September 1979, pp. 171-186.

20.  Lager, J.A. et al.,  "Urban Stormwater Management  and Technology:
        Update and Users' Guide,"  EPA-600/8-77-014, U.S. Environmental
        Protection Agency, Cincinnati, Ohio, September 1977.

21.  Levenspiel, 0.,  Chemical Reaction Engineering, Second Edition,  John
        Wiley and Sons, Inc., New York,  New York,  1972.

22.  Medina, M.A., "interaction of Urban Stormwater Runoff, Control  Measures
        and Receiving Water Response," Ph.D. Dissertation, Department of
        Environmental Engineering Sciences, University of Florida,
        Gainesville,  Florida, 1976.

23.  Nix, S.J., Heaney, J.P., and Huber, W.C., "Water  Quality Benefits
        of Detention", Chapter 12 of  "Urban Stormwater Management",
        Special Report No. 49, American Public Works Association,
        Chicago, Illinois, 1981.

24.  Rich, L.G., Environmental Systems Engineering, McGraw-Hill, Inc.,
        New York,  1973.

25.  Small, M.J. and DiToro, D.M., "Stormwater Treatment Systems,"
        Journal of the Environmental  Engineering Division, ASCE, Vol. 105,
        No. EE3, June 1979, pp. 557-569.
                                     C-117

-------
26.  Smith, R.,  "Preliminary Design and Simulation of Conventional Waste
        Renovation Systems Using the Digital Computer," Report No. WP-20-9,
        U.S. Department of the Interior, Federal Water Pollution Control
        Administration, Cincinnati, Ohio,  March 1968.

27.  Viessman, W., Jr., Knapp, J.W., Lewis,  G.L., and Harbaugh, I.E.,
        Introduction to Hydrology, 2nd edition., IEP, New York, New York,
        1977.

28.  Ward, A.J., Haan, C.T., and Barfield, B.J. , "Simulation of the
        Sedimentology of Sediment Detention Basins," Research Report No. 103,
        University of Kentucky, Water Resources Research Institute,
        Lexington, Kentucky, June 1977.

29.  Whipple, W., and J.V. Hunter, "Settleability of Urban Runoff Pollution",
        Water Resources Research Institute,  Rutgers U., New Brunswick,  New
        Jersey,  1980.
                                     C-118

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Addendum I - Review of Basin Data -. Met. Washington, D.C.  COG




     The use of event quantity and quality data for two basins in the




Washington, D.C. area for the purposes of estimating basin performance




proved fruitless.  A quick review of the data reveals a lack of any rela-




tionship between inflow and outflow events.  In many cases, the outflow




volume is greater than the inflow volume.  This is possible only if flows




from earlier storms are also being released.  Without more knowledge of




the operation of these basins, a statement about performance is impossible.




However, it may be possible to use these data, with complete knowledge of




the basin design and operation, to calibrate a simulator such as the SWMM




Storage/Treatment Block.
                                C-119/120 blank

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            APPENDIX D




WET WEATHER WATER QUALITY CRITERIA
                  D-l

-------
                                 APPENDIX D
                   WATER QUALITY CRITERIA FOR URBAN RUNOFF


The section that follows provides the information and methods developed to
date for the selection of receiving water quality criteria appropriate for
urban runoff.  The issue here centers around the difference between the ex-
posure regime used in toxicity tests to develop general water quality cri-
teria (48 to 96 hours or longer) and the exposure regime organisms inhabiting
runoff receiving waters could encounter (4.5 to 15 hours).  The criteria
based on 48 or 96 hour toxicity tests are postulated to be overly restrictive
for urban runoff exposures.  For the priority pollutants, the EPA published
criteria are described; the limitations of the EPA criteria for urban runoff
are discussed; and methods to adjust the EPA criteria for short-term urban
runoff exposures are presented.  Dissolved oxygen and suspended solids cri-
teria are also considered.

PRIORITY POLLUTANTS CRITERIA

EPA Criteria.
In developing the proposed priority pollutant criteria, EPA performed three
steps as follows:  (1) guidelines were established for use in deriving the
criteria, (2) criteria were computed for the protection of human health and
aquatic life, and (3) a two-value criterion for each substance was considered
for protection of aquatic life.  The two values are a maximum, which protects
against acute toxicity, and a 24-hour average, which protects against chronic
toxicity.

Using their guidelines, EPA derived and published (in three issues of the
Federal  Register, the last being 28 November 1980) aquatic life and human
health criteria for all  of the priority pollutants.  Criticism of the guide-
lines resulted in the development of a second set of guidelines which, unlike
the first set, specified certain minimum data requirements for deriving
aquatic life criteria.  These minimum requirements severly limited the num-
ber of substances for which criteria could be developed.  Hence, although
criteria documents were published for all  of the priority pollutants, aquatic
life criteria were developed for only 20 of them.  These are arsenic, cad-
mium, chromium, copper, lead, mercury, nickel, selenium, silver, zinc, aldrin,
chlordane,  cyanide, DDT and metabolites, dieldrin, endrin, heptachlor, lin-
dane, polychlorinated biphenyls, and toxaphene.

To obtain the final acute value for protection of aquatic life the following
procedure based on LC50 concentrations was used.  Note that a LC50 is defined
as the concentration that will kill 50 percent of the exposed population of
organisms during a specific period of time.

     1.  The geometric means of LC50 toxicity tests for a pollutant were
         computed by species.  The 48 hour exposure time was taken as


                                     D-2

-------
         the end-point of the test for most invertebrates and 96 hours for
         fish and some invertebrates.

     2.  LCSO's for the species were numerically ranked and the numbers
         transformed to cumulative probability values.

     3.  A least square regression line, defining the relationship between
         species-probability values and the mean LCSOs was computed.

     4.  The mean LC50 corresponding to a probability of .05 was identified
         by interpolation or extrapolation.

The mean LC50 corresponding to a species probability of .05 was defined as
the maximum criterion value.  Computed in this fashion, the maximum value
corresponds to the concentration above which lie the LC50s of 95 percent of
the tested species.  For pollutants whose toxicity was determined to be af-
fected by some natural property of water, the final acute equation was speci-
fied as the means for computing the maximum criterion value.  Hardness was
the only natural property of water considered.

The final chronic values were computed by much the same method as described
above; however, the important differences are:

     1.  The exposure times for chronic tests were at least 28 days.

     2.  The test end-point was not the LC50 concentration; rather the
         concentration values were the geometric means of the lowest
         tested concentration that caused a statistically significant
         adverse effect and the concentration immediately below it in
         the test series were used.  When there were insufficient data
         to compute a final chronic value from chronic data alone, the
         final acute-chronic ratio (defined as the ratio between the
         LC50 and final chronic value) was employed.

Generally, the 24 hour average criterion corresponded to the final chronic
value.  In some cases, however, a final residue value, designed to prevent
unacceptable tissue concentrations of pollutants determined the appropriate
24-hour criterion.

Application of the EPA Criteria to Urban Runoff.
A limitation of the EPA criteria centers around differences in the exposure
regimen commonly used in toxicity tests (data from which the criteria were
derived) and the exposure regimen that organisms inhabiting runoff receiving
streams could encounter.

The temporal features of urban runoff events consist of relatively short dur-
ation exposures with relatively large time periods, between episodes.  For
                                     D-3

-------
sites located in much of the eastern portion of the country, rainstorm sta-
tistics (or average) are as follows:

                                     Storm             Time Between Storm
                                     Duration          Midpoints
                                     (hours)           (hours)
                          /
     Median (50 percent!le)             4.5               60
     Mean                               6.0               80
     90 percentile                     15.0              200

For the semi-arid region of the western part of the country, storm durations
are generally the same as for the eastern U.S., but the period between storms
is about twice as long.  Runoff discharge times are somewhat longer but gen-
erally similar to storm duration times.

The above characteristic time scales are very different from those considered
in developing the EPA water quality criteria.  Therefore, a question exists
as to:  what are appropriate water quality criteria for highly time variable
discharges such as urban runoff?  That is, are the EPA criteria overly re-
strictive for urban runoff exposures?

It is well known that with the kinds of biological responses measured in
toxicity tests (with aquatic organisms), the concentration of a chemical
substance required to elicit a response of a given magnitude, be it some
percentage of mortality, reduction in growth rate, reduction in fecundity,
etc., is usually inversely proportional to the time of exposure.  For the
priority pollutants, data used to derive the maximum criterion value were
chosen only from 48- and 96-hour tests.  Data used to derive the 24-hour
average criterion value were chosen from tests with exposure times of at
least 28 days.

Because the duration of storms is much shorter than the exposure times used
in toxicity tests, it is quite likely that use of the criteria to assess the
hazard of urban runoff will overestimate the hazard.

Time is not the only factor of difference.  In toxicity tests, the test or-
ganisms are exposed to constant concentrations and exposure is continuous
throughout the test.  In urban runoff receiving waters, the concentrations of
potentially toxic constituents change continuously during events as well as
from event to event.  Runoff events are episodic, occurring on the average of
every 60 hours.  Although repeated exposure to chemical substances in the
runoff could cause chronic effects in organisms, little is known about the
effects of such repeated exposures.  The occurence of adverse effects
probably is greater when exposure to a given concentration is continuous
rather than intermittent.

The maximum criteria values proposed by EPA are LC50s (EPA used 48 and 96 hour
LC50s).   Because of differences in individual sensitivity, it is not necessar-
ily true that a population must be exposed to a 48 or 96 hour LC50-for 48 or
96 hours for 50 percent mortality to occur.  Figure la, b and c show a set of
hypothetical  time-mortality curves for populations exposed to a 96-hour LC50
of a chemical.


                                     D-4

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     100
                             100
                                                     100
      so
                              50
                                                      50
O £
            24
                 48
                      72
                          96
                                    24
                                        48
                                             72
                                                  96
                                                            24
                       48    72   96
                 (a)
(b)
(c)
                        Figure  1.   Time  Mortality Curves
  Figure  la  represents  a  case where  only during the last few hours of the test
  does  any mortality occur.   During  those hours,  50 percent of the organisms
  die.  Such a time-mortality pattern  is extremely rare.   Figure Ib illustrates
  a  case  where mortality  occurs  gradually and reaches 50 percent around the
  96th  hour.   Figure Ic shows a  case where 50 percent of the population dies
  during  the first 24 hours.   Figures  Ib and Ic represent the most commonly
  observed kinds  of time-mortality patterns and indicate that exceedance of a
  maximum criterion value for very short periods  could cause death or adverse
  sublethal  effects in  some  sensitive  species.   These types of responses par-
  tially  illustrate the complexity of  the situation.   The procedure presented
  below could be  used to  differentiate these types of responses and provide
  information directly  usable to assess the impacts of urban runoff.

  The runoff discharge  duration  may  not always  be an  accurate measure of expo-
  sure  time.   In  some instances, exposure time  can be much longer than the
  storm duration.   Certain kinds of  organisms could be exposed to runoff con-
  stituents  long  after  discharge ceases.  Such  organisms include phytoplankton
  and zooplankton (including fish eggs and larvae), each of which could become
  entrained  in the runoff plume.  The  net effect is that a percentage of cer-
  tain  populations may  experience longer exposure times.

  Even  for situations where  the  organism exposure time is longer than the ac-
  tual  discharge  period,  the differences in exposure regime for organisms in
  runoff  receiving waters and for organisms in  toxicity tests are very large.
  For example, to derive  the 24  hour average criterion values, an exposure time
  of at least 28  days was used.   It  is quite possible that for urban runoff, a
  24-hour criterion value is not appropriate.  For the same reasons, the pro-
  posed maximum criterion values may also be inappropriate for urban runoff.
  For the NURP project, procedures to  explicitly consider the short duration
  exposures  characteristic of urban  runoff were investigated as described below.

  Impairment of Beneficial Use Criteria.
  Impairment of beneficial  use will, for the following discussion, be consid-
  ered  concentrations that result in mortality  of 50 percent of the population
                                       D-5

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(i.e., LCSO's).  Other criteria, such as no mortality, could also be devel-
oped and employ similar calculation procedures.  It is evident from the pre-
vious discussion that use of the EPA criteria will  probably overestimate the
hazard of urban runoff to aquatic life in terms of impairment of beneficial
use.  This section addresses modifications to the criteria that would make
them more appropriate for assessing water quality problems associated with
urban runoff defined in terms of beneficial use.

Two methods are presented to establish criterion levels.  The first proce-
dure involves adjusting the maximum criteria value to explicitly consider
the expected exposure times (LIU, 1979).

The second approach employs the data on equivalent mortality dosage, detoxi-
fication rates, and expected mean concentrations in urban runoff (MANCINI, 1982)

The first procedure adjusts the maximum criterion values so that they relate
more closely to expected exposure times in runoff receiving streams.  This
entails computing a value that when divided into the maximum criterion value
of a pollutant will provide an estimate of the LC50 corresponding to the
exposure time of interest.  This LC50 is called the time-adjusted LC50, and
is computed as described below.  The assumption is  that meeting the adjusted
criteria for intermittent exposures, provides the same degree of protection
implied by the base criteria value, that is, that a generally healthy
aquatic life population will be maintained.

A set of factors for converting 24-, 48-, and 72-hour LCSO's to 96-hour
LCSO's were presented in the 18 May 1979 issue of the Federal Register
(40 FR 21506).  The factors are 0.66, 0.81, and 0.92 and are the respective
geometric means of all  96:24, 96:48, and 96:72 hour LC50 ratios computed for
individual chemicals on a test-by-test basis using  LC50 estimates available
at that time.  The relationship between the 24, 48, and 72 hour exposure
times and the factors for converting the LCSO's associated with these expo-
sure times to 96-hour LCSO's is described by the linear equation:

                        y = (0.563 log1Q x) - 0.123.                      (1)


Where x is the exposure time in hours and y   is the 96:x LC50 ratio.  The
correlation coefficient for this relationship is 0.998.

To extend the range below 24 hours, geometric means of the 96:1, 96:2, 96:4,
96:8, and 96:16 hour LC50 ratios were computed using experimental 1, 2, 4, 8
and 16 hour LC50 estimates for 10 chemicals (June,  1979).  These short expo-
sure means and the above values obtained by EPA were included in a least
squares regression.  The analysis indicated that the relationship can be
described by the linear equation:

                         y = (0.35 log1Q x) + 0.27                        (2)


The correlation coefficient for this relationship is 0.994.  Clearly,
Equation (2) can be used to convert a LC50 for an exposure time less than
96 hours to the 96 hour LC50 value, or to convert a 96 hour LC50 to a LC50
for a smaller exposure time.

                                     D-6

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Equation (2) was used to convert 96 hour LCSO's obtained by Liu for the
10 chemicals considered to LCSO's for exposure times of 1, 2, 4, 8, and
16 hours.  The computed short exposure LCSO's were compared to measured
values with reasonably good agreement.

The time-adjusted maximum criterion value (CV.) is computed from the maximum
criterion value (MCV) using the equation:
                                 CVt •                                    (3)

Applying the conversion method to the maximum criterion value instead of to
some specific 96-hour LC50 is valid because the maximum criterion value could
be considered a 96-hour LC50.  It was derived from 48-hour LCSO's from tests
with certain invertebrates and 96-hour LCSO's from tests with fish and cer-
tain invertebrates.  The 48- and 96- hour LCSO's were considered equivalent
end-points.  As indicated by Equation (3), the adjustment ratio y is assumed
to be the same for all chemicals.

Table 1 presents the maximum criterion values and time-adjusted criterion
values for all of the priority pollutants for which maximum criterion values
are available.  The time-adjusted values correspond to exposure times of 4.5,
6.0, 15 hours, which for at least the eastern portion of U.S. are the median,
mean, and 90th percentile duration of storms.

The second approach which has been used to estimate concentration levels
against which intermittent exposure concentrations due  to urban runoff can  be
compared, and employs data on equivalent mortality dosage, detoxification
rates, and mean concentrations in urban runoff.

The framework considers uptake and depuration of toxics by organisms and cal-
culates an equivalent toxic dosage.  The calculation results provide a method
of obtaining a dose response relationship for organisms which are subjected
to time variable toxic concentrations.  The framework employs data collected
from standard bioassay test procedures to evaluate the  coefficients required
in the analysis.  The procedures have been tested under four sets of condi-
tions which employed constant concentration bioassay results to predict or-
ganism mortality as a result of exposure to time variable concentrations.

A series of calculations were developed which considered exposure of the more
sensitive  fish (in a limited data base that had been analyzed) to a series  of
average duration storm events having the mean concentration of each contami-
nant.  The interval between storms was 60 hours (the median).  The calculated
equivalent dosage was allowed to stabilize, and the concentration required  to
produce mortality at the 50 percent level of population sensitivity was cal-
culated.  The results are summarized in Table 2.  These results include the
effects of carryover between average storm conditions.  The calculated con-
centrations for mortality are presented for 4.5 and 12-hour duration storms
(the 50 and 85 percentile, respectively).

While the concentrations provided by the first procedure are essentially es-
timates of "safe"  levels, those  provided by the second  procedure  provide es-
timates of intermittent concentration levels which would result in a serious

                                     D-7

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                TABLE  1.   MAXIMUM AND TIME-ADJUSTED CRITERION VALUES FOR SELECTED PRIORITY  POLLUTANTS
POLLUTANT
Arsenic
Cadmium
Chromium (+3)
Chromium (+6)
Copper
Lead
Mercury
Nickel
Selenium (Selenite)
Silver
Zinc
Aldrin
Chlordane
Cyanide
DDT (p,p)
Dieldrin
Endrin
Heptachlor
Lindane (gamma HCB)
Toxaphene
EPA MAXIMUM
CRITERION VALUES
(yg/*)1'2
440
3.0
4,700
21
22
170
4.1
1,800
260
4.1
320
3.0
2.4
52.0
1.1
2.5
0.18
0.52
2.0
1.6
TIME-ADJUSTED MAXIMUM CRITERION VALUES (jag/H)
4.5 HOURS
880
6
9,400
42
44
340
8.4
3,600
520
8.2
640
6.0
4.8
104
2.2
5.0
0.36
1.04
4.0
3.2
6.0 HOURS
810
5.5
8,650
39
40
313
7.7
3,300
480
7.5
590
5.5
4.4
96
2.0
4.6
0.33
0:96
3.7
2.9
15 HOURS
650
4.4
6,900
31
32
250
6.2
2,650
380
6.0
470
4.4
3.5
76
1.6
3.7
0.26
0.76
2.9
2.4
CO
       1  Values specified for "total  recoverable"  metals
       2  Values based on a hardness of 100  mg/£  as  CaC03

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         TABLE 2.  CALCULATED CONCENTRATIONS REQUIRED FOR MORTALITY
              OF  SOME FISH SPECIES AS A RESULT OF EXPOSURE TO
                                 URBAN RUNOFF
Event Mean ,,v
Concentration^'
ygA
Chemical
Zinc
Copper
Lead
Cadmium
Urban
Runoff
160
30
330
3
(2\
Concentration (ug/£) for 50% Mortality1 '
Urban Runoff
Storm
4.5 HR
1800
600
11,000
11
12 HR
800
200
4300
5
 NOTES:  (1)  Event mean concentration was not obtained from the NURP
              data base.

         (2)  Effects of carry-over of expected mean concentrations and
              other average storm conditions are included.


adverse impact (50 percent kill  of the selected species).   The  assumption
utilized in the screening calculations which evaluate impact levels, is
that such events,  while they would,  constitute a severe insult  to the
biological  population, would not totally deny that  use if  they  were to
recur at sufficiently infrequent intervals.

A comparison of the "safe" concentrations in Table  1 and the calculated
concentrations for 50 percent mortality in Table 2  indicate that there are
substantial differences.  In addition to the fact that they represent
different levels of effect, these differences are in part  a result of the
differences in data base used to define sensitive species.  Another equally
important source of this difference, is the manner  in which the duration
of exposure has been included in the analysis.

Neither set of concentrations are completely satisfactory  criteria for
storm event related exposures.  The published criteria do  not explicitly
account for the time scale of exposures associated  with storm events.
These criteria tend to be over protective of the environment by restricting
allowable concentrations during the short exposure  periods characteristic
of runoff events.   By contrast, the adjusted criteria presented in Tables 1
and 2 tend to overestimate allowable concentrations since the data base
analyzed may not include representative sensitive species which require
protection.

Assuming little or no exposure under non-storm ambient conditions, concen-
tration criteria which are appropriate for storm related  phenomena would
be between the two sets of values.  Methods have been developed which would
employ the existing data base to calculate criteria which consider time
                                    D-9

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variable concentrations and exposure periods which are consistent with
storm event exposure durations and the interval  between storms.

Chronic Effects

The usual approach to establishment of water quality criteria considers
acute effects such as mortality and chronic effects such as inhibited
reproduction, etc.

The EPA criteria derive the maximum value from acute effects protection
limits and the 24-hour value from chronic effects protection limits (as
derived by an acute/chronic ratio times the maximum).   A method is avail-
able to calculate the time history of stress on  the organism ("equivalent
exposure").  The equivalent mortality dose producing mortality of 50 per-
cent of the population is obtained from the analysis of bioassay data.
The calculated equivalent dose at any time which results from some sequence
of exposures can be divided by the equivalent mortality dose.  This ratio
(as % of equivalent mortality dose) could be considered as a measure of
the chronic stress to which the organism is subjected.

Table 3 presents the calculated percent equivalent mortality dose carried
over (on average) from a sequence of storms.  This is the calculated equi-
valent mortality dose at the start of a storm event.  Table 3 also presents
information on the calculated percent equivalent mortality dose at the end of
4.5 and 23 hour storms whose concentrations are  at the mean expected value.
These results suggest that, for some of the toxics analyzed, a variable but
moderately high level of stress may result from  exposure to the undiluted
contaminants in urban runoff.  Stresses on the order of 2 to 25 percent of
the equivalent mortality dose could produce some chronic effects (and pos-
sibly some acute effects as well).  The calculations presented in Table 3
are for undiluted urban runoff.  Computations could be developed consider-
ing various dilutions of the runoff.
           TABLE 3.   CARRYOVER EFFECTS BETWEEN  URBAN  RUNOFF STORMS
Chemical
Zinc
Arsenic
Copper
Lead
Chromium
Cadmium
Expected Mean
Concentration
(mg/£)
.163
.05
.03
.325
.018
.003
% Mortality Stress
Average
Carryover
8.6
-
2.6
8.3
-
2.3
@ 4.5 hr.
Storm
15.7
-
6.4
8.8
-
3.1
@ 12 hr.
Storm
26.8
-
12.2
9.7
-
4.4
                                     D-10

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Dissolved Oxygen Criteria.
Water quality criteria for dissolved oxygen (D.O.), which are specifically
designed for exposures associated with urban runoff, have not been examined
in detail.   EPA promulgated criteria set a minimum D.O.  of 5 mg/&.  D.O.
standards such as those proposed by the State of Ohio (Federal  Register
Vol. 45, 231, 11/28/80, 79054) for warm water fisheries  on some water bodies
specifying 5 mg/A for 16 hours of any 24 hour period and not less than 4  mg/SL
at any time were denied by EPA.   There is strong historical  precedence for
maintaining D.O. standards on most water bodies at a minimum of 5 mg/£.   This
is usually based on information similar to that summarized in Table 4.

An approach to dissolved oxygen water quality criteria similar to that used
for priority pollutants can be considered.  Based on the information summarized
in Table 4, criteria for D.O. during storm event time scales could be set at
2.5 mg/t.

            TABLE 4.  SUMMARY OF THE INFORMATION AVAILABLE ON THE
                  EFFECTS OF DISSOLVED OXYGEN CONCENTRATION
                                    ON FISH
     Dissolved Oxygen
Effects Reported
     Reference
    Saturation to
    5
    5 mg/A to 2.5 mg/i.
    2.5 mg/fc to
    1.5 mg/SL
    1.5 mg/H to zero
Generally considered
adequate for a healty
population.

Sublethal effects on
adults observed in
laboratories.

Reduced growth rate
associated with con-
stant exposure of
adults.

Some increased morta-
lity of early life
stages (no direct data
on population effects).

Time variable exposures
(8 to 12 hours every 24
hours) appeared to
result in reduced
growth rates.

Possible mortality of
adult and/or smaller
fish due to combina-
tion of stresses with.
significant D.O. con-
tribution to mortality.

Fish mortality (short
exposure).
USEPA (7)
(Abernathy) (28)
                                                       (Siefert et al.) (29)
                                                       (Moss) (26)
                                                       (Warren) (30)
                                                       (Whiteworth) (31)
(Moss) (26)
(Abernathy) (28)
(Warren) (30)
(Moss) (26)
(Warren) (30)
                                     D-ll

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Total Suspended Solids Criteria.
The  link between total suspended solids (TSS) concentrations and impairment of
beneficial use is not well defined.  Except at very high levels, the primary
aquatic life effects of TSS are indirect.  These include such problems as
benthic impacts due to deposition and scour which cause habitat damage, espe-
cially in areas subject to lower stream flow velocities.  To estimate some
measure of TSS levels for urban runoff, the findings of a 1965 study of suspended
solids effect by the European Inland Fisheries Advisory Commission was adopted.

The  Commission's study resulted in the following conclusions relating to
inert solids concentrations and satisfactory water quality for fish life:

1.   There is no evidence that concentrations of suspended solids less than
     25 mg/Ji have any harmful effects on fisheries.

2.   It should usually be possible to maintain good or moderate fisheries
     in waters which normally contain 25 to 80 mg/£ suspended solids.  Other
     factors being equal, however, the yield of fish from such waters might
     be somewhat lower than with less than 25 mg/&.

3.   Waters normally containing from 80 to 400 mg/£ suspended solids are
     unlikely to support good freshwater fisheries, although fisheries may
     sometimes be found at the lower concentrations within this range.

4.   At best, only poor fisheries are likely to be found in waters which
     normally contain more than 400 mg/& suspended solids.

The  Commission report also stated that exposure to several thousand mg/& for
several hours or days may not kill fish and that other inert or organic solids
may  be substantially more toxic.

Summary of the Criteria Used.
There are clearly limitations and problems with the various criteria as
discussed above.  Considering this situation, the NURP project has adopted a
number of criteria for use in the study.  The EPA criterion values for prior-
ity  pollutants were employed to represent water quality problems defined in
terms of numerical standards.  In addition, values based on the results of
the  procedures to establish criterion which explicitly consider the short-term
exposures of urban runoff were selected to represent water quality problems
defined in terms of beneficial use protection.

For  beneficial use protection, two numerical criterion values representing
"effects levels" were selected - one for mortality at approximately the 50
percent level of population sensitivity and a second which is the 50 percent
mortality value reduced by a factor of two.  This second value was taken to
represent no substantial  mortality which would effect the overall  population
and  therefore beneficial  water usage.


A summary of the water quality criterion  values  used  in  the  screening analyses
performed by NURP is  presented in  Table  5.   For  the  heavy metals,  the EPA
criteria are specified for "total  recoverable  metals."   The  effects  level
criteria were developed  from bioassay data  in  which  the  tests  used  soluble
salts of the metal.   The  criteria  thus  reflect only  the  toxic  species of
the heavy metals.   In  applying these  criteria, the solids content  of the
runoff and the tendency  for metals and  other priority pollutants to  absorb
to this  material  must  be  considered.

                                     D-12

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TABLE 5.  SUMMARY OF WATER QUALITY CRITERION VALUES USED IN NURP STUDY
                        CONCENTRATIONS -
CONTAMINANT
Zinc
Chromium (Total )
Copper
Lead
Cadmium
Arsenic
TSS4
BOD4
EPA CRITERIA1
24 HOUR
47
(40 )3
5.6
3.3
.025
(40 )3
25
5
MAX
320
4,700
22
170
3
440
250
15
EFFECTS LEVELS
ESTIMATED 5
THRESHOLD
600
8,650
40
313
5.5
810
2,500
50
50% b
MORTALITY
1,600
—
500
4,500
10
—


1  Based on a hardness of 100 mg/£ as CaC03.

2  Hardness not explicitly considered, but values developed from data in
   relatively soft water.

3  No criteria proposed - value shown is lowest observed chrome concen-
   tration reported in EPA documents.

k  No criteria for these pollutants - values  shown represent levels
   estimated to represent equivalent criteria effects (for use in
   screening analysis activities).

5  Based on Procedure #1 estimates of "safe"  levels for intermittent
   exposures (average duration 6 hr).

6  Based on Procedure #2 estimates of serious impact from intermittent
   exposures (average duration 6 hr).
                                  D-13

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                                 REFERENCES
Liu D.  H.  W.,  H.  C.  Carley, B.  E.  Suta, Static, Flow Through and Plug Flow
Bioassay Study with the Bluegill Sunfish Exposed to 10 Chemical Toxicants, by
SRI International, For EPA, contract 68-01-4108, 1979.

European Inland Fisheries Commission.  "Water Quality Criteria for European
Freshwater Fish Report on Finely Divided Solids and Inland Fisheries."
International  Journal of Air and Water Pollution, Vol. 9.  1965.

Mancini, J. L. "Development of Methods to Define Water Quality Effects of
Urban Runoff;"  EPA Cooperative Agreement No. 806828, (1982, in press).
                                    D-14

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      •   APPENDIX E



INDIVIDUAL PROJECT SUMMARIES
            E-l

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                                    Appendix E
     Summaries of conclusions for selected NURP projects are presented in this ap-
pendix.  The projects are presented in order by EPA Region number from I through X
as follows:
     Region I


     Region II


     Region III

     Region IV

     Region V
     Region VI


     Region VIII

     Region IX

     Region X
Lake Quinsigamond, MA
Durham, NH

Irondequoit Bay, NY
Long Island, NY

Baltimore, MD

Winston-Salem, NC

Lansing, MI
Ann Arbor, MI
Oakland County* MI
Glenn Ellyn, IL
Champaign, IL
Milwaukee, WI

Little Rock, AK
Austin, TX

Denver, CO

Castro Valley, CA

Bellevue, WA
                                        E-2

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  NATIONWIDE URBAN RUNOFF PROGRAM

   MASSACHUSETTS DEPARTMENT OF
ENVIRONMENTAL QUALITY ENGINEERING

      LAKE QUINSIGAMOND, MA

          REGION I, EPA
               El-1

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Lake Quinsigamond NURP.

     A major component of the work plan for the Lake Quinsigamond NURP project
was to evaluate the response of the receiving water to stormwater inputs.   A
detailed evaluation of the response of Lake Quinsigamond and Flint Pond to pollu-
tant loadings was conducted.  The evaluation was based on intensive lake and
tributary monitoring data collected under the 314 Clean Lakes Diagnostic study,
together with tributary and stormwater sampling data collected by the NURP project.
The analysis utilized a batch phosphorus model to simulate the most important
interactions affecting dissolved oxygen and algal populations in the lake.  Based
on this analysis, the major findings can be summarized as follows:

     .   Water quality conditions in Lake Quinsigamond and Flint Pond have  remained
        relatively stable between 1971 and 1980.   This can be largely attributed
        to the lake's morphology and self-limiting chemical  characteristics.

     .   Chlorophyll, transparency, and hypolimnetic oxygen depletion rated indi-
        cate that Lake Quinsigamond is in a late mesotrophic stage.   Despite its
        similar water quality conditions, Flint Pond is classified as eutrophic
        due to its aquatic weed densities.  The differences  between Lake Quinsig-
        amond and Flint Pond can be attributed to differences in morphological
        characteristics.
                                   •
     .   Major water quality problems identified in the lake  include hypolimnetic
        oxygen depletion, heavy metals build-up in sediments, near-shore solids
        deposition, and tributary bacterial levels.   Reduction of cold-water
        fisheries habitat is the major use-related impairment identified in the
        lake.  Bacterial  levels in the tributaries have resulted in the closing
        of one secondary water supply well (Coalmine Brook).  It is important
        to note that, in this case, urban runoff is  not, per se, the source of
        the problem.  Misconnections, leaky sewers,  and direct discharges  have
        been identified as the primary source of this problem.

     .   Excessive weed growth and heavy metals in sediments  have been identified
        as the major water quality problems in Flint Pond.   These have resulted
        in significant impairment of recreational use of the pond in terms of
        swimming, boating and fishing.

     .   Dissolved phosphorus has been identified as  the major limiting nutrient
        and most important from a control standpoint.  Lake  mass balances  and
        literature studies suggest that between 0 and 20 percent of the particu-
        late phosphorus loads entering the lake are  eventually able to support
        algal growth.

     .   Nutrient balance calculations indicate that  surface  runoff accounts for
        87 percent of the total phosphorus, 67 percent of the dissolved phosphorus,
        96 percent of the suspended solids, and 49 percent of the total  nitrogen
        input to the lakes.   Tributary base flow and atmospheric inputs account
        for the remaining loadings.  Dissolved phosphorus inputs to Flint  Pond
        from unsewered areas is nominally estimated  at 18 percent.
                                     El-2

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Lake Quinsigamond (Cont'd)

     .   Analysis of lake data in relation to antecedent rainfall  periods  indicate
        significantly higher concentrations of total  phosphorus,  dissolved phos-
        phorus, and coliform bacteria on wet days as  compared with dry days.
        More intensive sampling is required to more adequately assess the extent
        and significance of short-term bacterial  standards  violations in  specific
        areas of the lake.

     .   Future land uses are estimated to result  in a 12-14 percent degradation
        in average water quality conditions, as measured by suspended solids,
        available phosphorus, and other eutrophication-related variables.  There-
        fore, control of 12-14 percent of future  available  phosphorus and suspended
        solids loadings would be needed to maintain existing water quality.

     .   Reduction of phosphorus loadings to insure 200 days of hypolimnetic oxygen
        supply at spring turnover is suggested as a potential water quality manage-
        ment objective.  This would reduce the potential for internal metals and
        nutrient cycling, improve fish habitat, and provide proportionate reduc-
        tions in chlorophyll and increases in transparency.

     .   Under projected future land uses, the above objective would require about
        a 50 percent reduction in loadings of available phosphorus in surface run-
        off during an average hydrologic year. Control  requirements during a wet
        hydrologic year would be more stringent (78%).

        Because of the importance of dissolved phosphorus loadings, watershed
        management strategies for reducing runoff volumes by "encouraging  water
        infiltration should be examined along with runoff treatment schemes as
        means of achieving water quality objectives.

     Based on the findings enumerated above, a comprehensive water quality manage-
ment plan is being developed of which the urban runoff component  is a major element.
Watershed management plans are being developed for each major tributary.   Natural
detention/storage mechanisms are being utilized as in-system filters for  solids
and nutrient controls to the maximum extent possible.  Wherever possible, ground-
water recharge options for stormwater are being considered.  End-of-pipe  and in-
line solids treatment systems are being considered for major stormwater systems
discharging directly to the lake (e.g., Route 9 drain, medical school drain,
1-290 drainage system).  Combinations of Best Management Practices, including
street-sweeping and catch basin-cleaning, among others,  are also  being considered
as appropriate in developing an overall stormwater management strategy for the
watershed.

     Finally, it is extremely important to recognize  that stormwater management is
one component of the water quality management plan under development.  Other
major components of this program are the control  of sanitary sewage discharges
via leaks, misconnections and other sources, and  septic system leachate inputs
from unsewered areas.
                               E1-3/E1-4 (blank)

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NATIONWIDE URBAN RUNOFF PROGRAM

 NEW HAMPSHIRE WATER SUPPLY AND
  POLLUTION CONTROL COMMISION

           DURHAM, NH

          REGION I, EPA
            E2-1

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Durham, New Hampshire

     Two streams were monitored at stations upstream of the urban area for back-
ground conditions, and at downstream locations where the effect of urban runoff
could be observed.  At one location; the Oyster River,  monitoring results from
three storm events show no detectable increase in concentrations at downstream
stations compared with upstream boundary levels during  storms.   (Not surprising
since "urban area" constitutes only about 6 percent of  the contributing catchment,
and 1/3 of this is Institutional  giving a Drainage Area Ratio  of 15.6.)  Pette
Brook, with 23 percent of the catchment above the downstream monitoring station
(DAR 3.3) shows a "trend of increased concentration" observed  during storms.   Data
are insufficient at this time for assessing whether the fishable/swimmable use
classification is impaired.

     Mass loads discharged into the estuary during storms appear to be significant
in magnitude when all sources (urban and non-urban) are considered.  The impact of
such loads on important downstream water bodies (the estuary),  whether a significant
effect on beneficial  use is probable, and whether the contaminant loads which  origi-
nate from urban areas are an important contributor to any detrimental  effect,  have
not yet been determined.

     Control techniques for reducing urban runoff loads will be evaluated for  their
ability to control any potential  problems that are anticipated  and will provide
important information for statewide programs.
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NATIONWIDE URBAN RUNOFF PROGRAM

 NEW YORK STATE DEPARTMENT OF
  ENVIRONMENTAL CONSERVATION

      IRONDEQUOIT BAY, NY

        REGION II, EPA
             E3-1

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                                 IBNURP

                         WATER QUALITY IMPACTS


     Irondequoit Bay is the receiving water body for a 153-square-mile watershed
in western New York.  The Bay is a prime water resource for the urbanized area
surrounding the City of Rochester.  However, much of the recreational potential
of the Bay is restricted by its advanced state of eutrophication.  The problems
associated with Irondequoit Bay - hypolimnetic oxygen depletion, turbidity,
and adverse fishery impacts - all result from the phosphorus-enriched status of
the Bay.  Local government has implemented a plan to eliminate all point source
discharges to the Bay and its watershed.  It is the intent of the urban runoff
project to examine the role of diffuse urban runoff pollution in the progres-
sive eutrophication of Irondequoit Bay.

     Seventy-five percent (75%), or 115 square miles, of the total watershed
is being studied under the urban runoff project.  The remaining twenty-five
percent (25%), or 38 square miles, at the upstream end of the watershed will
be part of a rural non-point sourge assessment study.  Preliminary land
use figures indicate that the NURP study area contains 36 square miles of
residentially developed lands (i.e., 31%), 12 miles square miles of commercial/
industrial development (11%) and 67 square miles of parkland/undeveloped land
(52%).  These figures typify the area which is undergoing intensive suburban
development with a major shift from active and inactive agricultural use to
residential use.

     A scan of the water quality parameters monitored during 1980 shows that
the event mean concentrations all fall within the range reported in the USEPA
Preliminary Report dated 9/30/81.  Detailed loadings from the individual land
use monitoring sites and the watershed as a whole are being developed for phos-
phorous, lead and suspended solids.  Preliminary results suggest that 55% of
the total phosphorous load comes from the urban study area which comprises 75%
of the total watershed area.  Conversely, the agricultural area, which com-
prises only 25% of the land area, produces 45% of the total phosphorous load.
The lead loading in the watershed appears to be directly proportional to the
land area: the agricultural area produced 25% of the load and the urban area
produced 75% of the load.  A more detailed breakdown of loadings within the
urban study area is underway.

     The project is considering several treatment and management options to
control urban runoff pollution including detention/retention facilities, street
sweeping, porous pavement, and decreased road salting.  One of the most prom-
ising proposals is to utilize an existing 100-acre wetland located at the
south end of the Bay to remove nutrients and suspended solids.  If managed
properly, this wetland would renovate the runoff from both the urban and rural
areas just prior to its entry into the Bay.  Monitoring sites have been con-
structed at the influent and effluent ends of the wetlands and they will provide
the basic information necessary for developing a phosphorous budget and esti-
mating sediment loss within the wetland unit.  The expected output from this
study will include recommendations for developing a demonstration project
in the wetland.
                                      E3-2

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     NATIONWIDE URBAN RUNOFF PROGRAM



LONG ISLAND REGIONAL PLANNING COMMISSION





          LONG ISLAND, NEW YORK



             REGION  II,  EPA

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       NATIONWIDE URBAN RUNOFF PROGRAM


              Long Island, N.Y.

            December 10, 1981
              PROJECT SUMMARY
     Long Island Regional Planning Board

             in cooperation with

          U.S. Geological Survey
     Nassau County Department of Health
Suffolk County Department of Health Services
                    E4-2

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               I.  PROJECT LOCATION

     The Long Island component of the NURP deals with the urban runoff problems
affecting the ground and surface waters of two New York Metropolitan Area
Counties:  Nassau and Suffolk.  The receiving waters of principal interest to the
counties of Nassau and Suffolk in the L.I. NURP program are the groundwater
reservoir and the south shore marine embayments.  The groundwater recharge basin
project sites are located at Laurel Hollow, Syosset and Plainview in the Nassau
Town of Oyster Bay and at South Huntington and Centereach, in the Suffolk Towns
of Huntington and Brookhaven, respectively.  The surface water project sites are
located at Unqua Pond and Bayville in the Town of Oyster Bay; on the Carll's
River in the Town of Babylon; and on Orowoc Creek in the Town of Islip.


              II.  PROJECT DESCRIPTION

A.  Urban Runoff Related Problems

     The quantity and quality of available groundwater and the-quality of surface
waters have long been concerns of Long Island officials and residents, who recog-
nized their dependence on the groundwater for potable supplies and on the surface
waters for recreation and for the economically important shellfish industry.  The
208 Study, which addressed these concerns, found that stormwater runoff is a major,
and in many cases, the major non-point source of pollution in the bi-county region.
The 208 investigations indicated that runoff from highways, medium and high density
residential areas, and commercial and industrial areas was contributing varying
amounts of coliform bacteria, organic chemicals, sediment, heavy metals, and
nitrogen to both ground and surface waters.

     A question was raised as to whether the more than 3000 recharge basins or
sumps used throughout the island as outlets for local drainage systems and as
devices for replenishing the aquifers were contributing to the areawide contam-
ination of the drinking water.  Did the basins function as conduits facilitating
the entry of water borne pollutants or did they function as control devices fil-
tering out some or all of the pollutants?

     Stormwater runoff was identified as the major source of bacterial loading
to marine waters and, thus, the indirect cause of the denial of certification by
the New York State Department of Conservation for about one fourth of the shell-
fishing area, an area containing an estimated one third of the clams.  Much
of this area is along the south shore, where the annual commercial shellfish
harvest is valued at approximately $17.5 million.  Figure 1 shows the location
of areas closed to shellfishing as of June 1981.  Deep embayments along the
north shore provide an important recreational resource and, to a lesser extent,
shellfish beds.  Runoff-related closure of bathing beaches in response to ele-
vated coliform counts is a minor problem since such incidents tend to be rela-
tively infrequent and of short duration.
B.  Legal/Political Implications, Public Attitudes

     There are local legal implications of Long  Island's runoff prob-•
lems; however, they do not appear to be as significant as in many areas
Inasmuch as the drainage basins contributing runoff, and the receiving
waters, are generally located within the same political jurisdiction

                                  E4-3

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 there Is no question of municipal liability for the diminution of the rights of
 the downstream user as is often the case in a riverine situation.  There is a
 legally established long term denial of a beneficial use —the taking of shellfish —
 in portions of the bay in response to the presence of coliform bacteria at levels
 in excess of the prescribed New York State standard 70mpn/100ml for the certification
 of shellfishing areas.  In addition there is a similar relatively infrequent, short
 term denial of the beneficial use of certain beaches, based upon the existence of
 coliform levels that contravene the standards for bathing or contact recreation,
 2400mpn/100ml.

     The legal implications of the proposed control measures vary from measure to
 measure.  In the case of stream corridor storage and stream bed infiltration legal
 difficulties appear unlikely so long as the area subject to inundation is not in-
 creased beyond the historical limits of the floodplain and so long as groundwater
 elevations and impoundment levels do not exceed those that prevailed during wet
 years prior to sewering and the consequent drop in water table elevations.

     Any modification of the stream beds to provide stonnwater flow to maintain
 freshwater wetlands or to improve percolation could involve questions of owner-
 ship and on occasion the need for temporary or permanent easements.

     Police power intervention may be required to protect the beds of streams and
 ponds that are drying up from the type of encroachment that would impair their
 usefulness in retaining or detaining runoff.

     In the case of pond modifications such as dredging, the construction of
 weirs, or the installation of baffles to avoid short circuiting and increase
 detention time, not only the ownership of the bottom, but also the rights of ad-
 jacent and nearby residents to recreational use of the waters would have to be
 considered.

     The reliance on land use controls, such as zoning, subdivision regulations
 and the acquisition of the fee or lesser interests  in land in order to preserve
 or protect stream corridor areas not already dedicated for open space or con-
 servation purposes,raises political and fiscal rather than legal questions.
 Similarly, changes in drainage system requirements to foster use of the Bayville
 type leaching system; the prohibition of duck feeding; and the enforcement of
 existing wetlands protection and dog controls involves problems of costs and pub-
 lic acceptance rather than legal authority.

     Both the problems and the proposed controls have political implications.
 There is political dissatisfaction resulting from the denial of beneficial uses
 of marine waters.  This has been manifested in the growth of baymen's, sportsmen's
 and conservation organizations that have lobbied for improved water quality in
 nearshore areas and/or changes in the New York State standards for certification.
 seeding of open shellfishing areas and habitat creation or restoration.


     As for the control measures,  there appears to be little or no political
opposition to storage and stream bed infiltration and freshwater wetlands pre-
 servation.  In fact,  to the extent that NURP  control measures obviate the need for
 remedial action to offset groundwater losses  attributable to sewering, they may
generate considerable political  support.


                                     E4-4

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     There  Is likely  to be moderate  to significant opposition to other proposed
measures because of the Relatively minor) capital outlays required for pond modi-
fications and the  Installation of leaching systems, the major capital outlays
for the acquisition of lands or development rights, and the potential loss of
rateables.

     Opposition to the enactment of  a ban on the feeding of waterfowl and to the
enforcement of dog control and tidal wetlands laws arises not so much from fiscal
concerns as from the  view that such  actions constitute an unwarranted infringe-
ment of personal and  property rights.

     Public attitudes affect both the perception of the problem and the willing-
ness to support mitigating measures.  Many Long Island residents have little
understanding of causal relationships, particularly in the case of stormwater
runoff.  Public concerns in respect  to recharge basins have focused on issues of
safety and  appearance rather than water  quality.  As for marine waters, the at-
titude has  generally  been one of annoyance with the inconvenience of beach
closures and a tendency to regard them either as the result of an "act of God"
or the fault of New York City.  Recreational and commercial shellfishermen,
although frequently at odds with one  another, share a common desire for im-
provements  in water quality and for  changes in what they regard as unnecessarily
stringent certification requirements.

     The need for  strong public support  for proposed control measures, especiallj
those such  as a ban on waterfowl feeding  and pooper-scooper laws that must rely
on voluntary compliance, indicates the need for a well designed, well-funded
public education program.

C.  BMP's Investigated

    1.   Nassau County Department of Health

        a.   Natural Impoundment - Unqua Pond, Massapequa
            1) Location;  Southest corner of Nassau County, New York
            2) Drainage Area;   298.5 acres, consisting of
                               253 acres  (85%) medium density residential
                                15 acres  (5%) commercial
                                30 acres  (10%) open space
            3) Description:  5.5 acres "natural" impoundment with a depth of 3-5
                 feet having a baseflow volume of approximately 900,000 cu. ft.
                 Rectangular in shape, north, east, south shore lines - parklancs;
                 west shore - residential.
            4) Effectiveness;   75-95% removal of bacteriological loading (total
                 coliform, fecal coliform, fecal streptococci) from surface runoff
                 to south shore embayments during low to medium storm events (i.e.,
                 1 inch/24 hrs. or less).  This type of storm event comprises the
                 majority of the annual precipitation events.

                 Suspended solids  removals by the impoundment are in the range
                 of 43-75% for low/medium storm events and 40-56% for larger stcrm
                 events (i.e.,  more than I"/24 hrs.).
            5) Cost;   Negligible - possible dredging costs as impoundment becomes
                 filled with sediment.
                                       E4-5

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    6) Problems:  The  impoundment  does not appear to effect significant
         removals during  larger  storm events  (i.e., more than l"/24 hrs.).
         What appears  to  happen  is a short circuiting of storm flow through
         the pond, allowing entering runoff to pass rapidly through or
         over the resident pond  water.  An example of such an occurrence
         was a storm event on September 15-16, 1981.  A total rainfall of
         2.44" was recorded during a 24-hour period.  A comparison of EKC's
         of influent and  effluent bacteriological parameters indicate no
         removal of total or fecal coliform bacteria,  there was a cor-
         responding 75% removal  of fecal streptococci.

b.  In-line stonnwater storage drainage system
    1) Location:  Northeast Nassau County, Inc. Village of Bayville
    2) Drainage Area:  65.6 acres of which 100% is medium density residential
         with 15% impervious land surface (9.8 acres).
    3) Description;  Separate storm sewer system consisting of a series of
         interconnected leaching pools (10 * diameter reinforced concrete
         perforated rings - 3 rings deep - 18') located below the street
         right of way into which stormwater flows from 6' diameter leaching
         type catch basins (12' deep).  Interconnecting piping is perforated
         to facilitate recharge  to groundwater.  Stormwater runoff first
         enters the leaching catch basins.  Once these basins are full and
         the influent of  runoff exceeds the leaching rate, the basins over-
         flow to the larger leaching pools located in series along the main
         storm sewer line.  As each pool fills to maximum capacity and if the
         rate of influent exceeds the leaching rate of the pool, the effluent
         will overflow to the next pool downstream.  The entire system
         produces a discharge to the estuarine receiving water (Mill Neck
         Creek)  only when the storage and leaching capacity of the systez
         are exceeded.
    4) Effectiveness:   Since construction of the system was completed in the
         fall of 1979,  there has been evidence of system overflow to the
         receiving water on two or three occasions.  These occurrences were
         during storm events with rainfall intensities of five inches/hour
         or more (e.g., intense thunderstorm activity).  The majority of
         storm events for this locale are much less intense and permit
         retention and recharge of the runoff to groundwater.
    5)  Cost:   Construction costs for the installation of the Perry Avenue  v
         In-Line Storage Sewer System was $836,855 (1979).  Cost covered
         all phases of construction including installation of leaching
         basins,  pools  and drainage pipe,  sidewalk and curb reconstruction
         and roadway regrading and resurfacing.

         The system includes 31 recharge-leaching pools, each consisting of
         10'  diameter reinforced concrete rings with concrete slab cover,
         28 leaching catch basins,  each consisting of 61 diameter reinforced
         concrete rings with concrete slab covers, curb inlets and road
         grates  and interconnecting reinforced, perforated concrete pipes
         ranging from 15" to 42" diameter.
    6)  Problems;   There have been some problems with subsidence of soils
         surrounding the mainline leaching pools.  This problem is seen zore
         as a  problem with installation of the leaching rings and proper
         backfilling than with the design of the system.

         The effectiveness of the system may decrease with age as cloggirg
         of soil  pores  continues.  Sediment and leaf removal from the leaching
         catch basins is necessary on at least an annual basis to maintain
         proper  functioning of structures.

                                  E4-6

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2.  Suffolk County Department of Health Services
    a.
 Orowoc Creek - Dry stream channel,  energy dissipation/wetlands
 1)  Location;  South Brentvood,  New  York
 2)  Drainage Area;  tfQ acres, all medium density residential
 3)  Description;   The site is at a  trapezoidal shaped  recharge basin
                   just to the north of the Southern State Parkway  in
                   South Brentwood,  Islip town, located on the service
                   road to the parkway.   The basin is approximately
                   450' long and 300' wide at its longest and widest
                   points.  There is a storm drain draining  a small
                   residential area  that  discharges into the east
                   side of the basin, roughly 200* downstream from
                   the stream influent point at the northern end of
                   the basin.  A low (8"-10" high)  concrete wall at
                   the end of the 10' long concrete apron to the
                   storm drain,  which has  been in place for at least
                   15  years,  acts as a working,  effective energy
                   dissipator;   The  basin  and stream channel upstream
                   are heavily overgrown with wetlands  vegetation and,
                   hence,  provide  an effective site for wetlands treat-
                   ment.   Upstream of the  recharge basin, the channel
                   is  dry  for much of the  year and resembles the
                   conditions predicted in  the Suffolk  County Flow
                   Augmentation Needs Study  (FANS)  for  streams
                   without augmentation.
4) Effectiveness;  Unknown  (as yet  untested).   SCDHS has been
                   looking  for a  site that may  be  monitored to
                   assess the stormwater runoff treatment benefits
                   that may be derived from  the drying  up of portions
                   of  streams due to the effect of sewering.  SCDHS
                   proposes to  (a) establish  a  monitoring station  at
                   the basin influent to evaluate  the  treatment pro-
                   vided by the dry stream channel,  (b) have a
                   monitoring station at the  storm drain discharge
                   to  the basin,  to sample runoff  from  the small
                   residential area and  (c)  sample  at  the basin effluent
                   to evaluate the  treatment  provided by the wetlands
                   vegetation and from recharge  in  the basin.

                   Because of the existence  of  heavy vegetation in
                   the channel up-stream and  also  in the recharge
                   basin, it is  anticipated  that  there would be several
                   storms for which  there may not be any flow measured
                   at the basin's influent or effluent points.   If
                   conditions of no  flow do occur  as expected,  then a
                   consequent total  removal of pollutants to surface
                   water will have been achieved as a result of energy,
                   dissipation,  retention, and percolation.
5) Cost:  Negligible - no routine maintenance costs.
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         6)  Note:   SCDHS la dropping the  energy dissipation construction at
                   Westvlew from the study for three  (3) reasons:

                   (1)   the low bid for constructing  the facility was $41,000,
                        which was approximately $20,000 more than the IMS es-
                        timate;
                   (2)   although SCDHS' field crew had identified 40 to 50
                        potential sites where energy  dissipation could be im-
                        plemented, the total contributory drainage area to
                        these sites is not as significant as originally en-
                        visioned before the site inspections were done; and,
                   (3).  energy dissipation/wetlands treatment can be evaluated
                        at  the storm drain discharge  to the Orowoc Creek site.

                        The Westview Avenue site would be retained in the moni-
                        toring program as a control for evaluating the impact
                        of  modifying the  street cleaning practices at Central
                        Avenue.   It is intended to sample both sites during
                        the same storm events.

    b.  Carlls River -  Street sweeping
        1) Location:  Deer Park,  New York
        2) Drainage Area;   73 acres, all medium density residential
        3) Description:  An area of 73 acres draining to Central Avenue is
                         being used to investigate the impacts of varying
                         frequencies of street sweeping on stormwater runoff
                         quality.  Sampling will be  conducted at a manhole at
                         Central Avenue and W. 42nd  Street which discharges
                         to a 45" x 72" oval drain.
        4) Effectiveness;   Unknown (as yet untested).
                         Monitoring will be conducted from March 1982 through
                         the Fall of 1982.  This work should be done because
                         street sweeping appears to  be one of the few control
                         options  for addressing the  contamination attributable
                         to direct runoff to the bay.
        5) Cost;  Approximately $600 per sweep (both sides of street).
                         Frequency  of sweeping is anticipated to be weekly,
                         thus the total cost (capital plus 0 & M) for the
                         program is  approximately $15,000-$20,000.

3.  U. S. Geological Survey

    a.  Stormwater recharge basins
        (All basins are approximately 1-3 acres in size and 14-40 feet deep).
        (1) Basins:
            (a) Plainview,  N. Y.
                -land use  - major highway
                -drainage  area  -  190 acres
                -Z impervious - 6.3
            (b) Syosset, N.  Y.
                -land use  - medium density residential (1/4-acre zoning)
                -drainage  area  -  28.2 acres
                -% impervious - 16
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     (c) Laurel Hollow, N. Y.
        -land use - low density residential (2-acre zoning)
        -drainage area - 100 acres
        -2 Impervious -4.7
     (d) Huntington, N. Y.
        -land use - parking lot and shopping mall
        -drainage area - 39.2 acres
        -% impervious - 100
     (e) Centereach, N. Y. (N.Y.S. Dept. of Transportation Ecological
        Recharge Basin: lined with plastic; holds water permanently
        up to predetermined level, above which exfiltration occurs
        through basin walls)
        -land use - strip commercial
        -drainage area - 68 acres
        -2 impervious - 6
(2) Effectiveness;
     (a) Bacteria: virtually 100% removal of total coliform, fecal
        coliform, and fecal streptococci after infiltration to the
        water table.
     (b) Heavy metals: high concentrations in stormwater (up to 3 ppm
        Pb, for example) reduced by 1-2 orders of magnitude.
     (c) Nitrogen: low concentrations of total nitrogen in stormwater
        (median values of 1-3 mg/1) indicate that stormwater is not
        a significant contributor of nitrogen to groundwater.
     (d) Chlorides: these ions tend to be conservative and are not re-
        moved during infiltration.  Median concentrations are low
        ( <_ 20 mg/1) except in the parking lot area, where the median
        concentration is 78 mg/1.
    (e) Priority pollutants: an extremely limited number of analyses
        indicates that priority pollutants in stormwater and ground-
        water are below the recommended limit of 10 ug/1 with two
        exceptions: 1,1,1 trichloroethane in Huntington groundwater is
        23 ug/1,  and 4,4-DDT in Plainview stormwater is 30 ug/1 (based
        on one analysis only).
(3) Costs;
         The only costs associated with recharge basins on Long Island
    are the initial costs of construction, implacement of security
    features such as fences, and landscaping.  No maintenance is re-
    quired due- to the sandy, porous nature of the soil.
(4)      Recharge basins-located  in sfiopptng^ceirter-areas tend tO'"be>
    come clogged  with oil debris, reducing their effectiveness and
    causing them to hold water at all times.  However, all recharge
    basins on Long Island are large enough so that this does not pre-
    sent any serious problems.
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            III.  PRELIMINARY  CONCLUSIONS REACHED
 A.  SURFACE WATERS

     1.  The significance of urban runoff as a contributor of coliform loadings
to surface waters, indicated in the L.I. 208 and ongoing .monitoring studies, has
been confirmed by extensive baseline sampling.  When load contributions from
point sources are factored out of the total loadings to the bays,  it is found that
coliform contamination levels remain high enough to keep shellfish beds closed.

      2.   Nassau  and  Suffolk Counties  represent  two  entirely  ditterent  situations
 in terms  of runoff effects  and  control.   The  western south shore bays of
 Nassau are subject to much greater  tidal  flushing, which distributes loadings
 throughout the Nassau Bay System.  The Suffolk  portion of  the bay is much more
 stable and,  hence, tends to concentrate  loadings close to  their discharge points.
 To achieve load  reductions  in Nassau, controls must  be instituted on a  global
 scale, while in  Suffolk reductions can be achieved  using localized controls.

      3.   An extensive stormwater runoff  modeling effort developed for  the
 study  has indicated  that a  reduction  of  total coliform loads of one to  two
 orders of magnitude  (90 - 99%) will lead to surface waters that meet current
 water  quality standards in  many areas.

     A.   Land uses within stream drainage basins have been disaggregated in an
 attempt to  quantify the proportion of runoff  from streams versus the prop-
 ortion attributable to direct overland runoff to tidal waters.  It appears
 that approximately 45% of the total coliform  load from runoff in Nassau and
 25% of the  total in Suffolk can be attributed to overland runoff.

     5.   Coliform removals  from runoff of 75  -  95%  have been observed  in Uncua
Pond.  This  is probably attributable  to  natural processes  (settling, filtration)
acting on  runoff.  The removals observed appear to  be inversely related to
rainfall magnitude (volume  and intensity).  High removals have been observed
for low volume, low intensity storms, which comprise the majority of Long Island
precipitation events.  Poorer removals have been observed for high volume,  high
intensity storms.

   6. The  in-line storage system with leaching pools performs very effectively,
but appears  to be hydraulically over-designed.

     7.  The use of stream  corridors to  replicate the natural processes
observed in ponds (detention, settling,  filtration) offers a promising means
of achieving a significant  degree of runoff control.  However, to achieve
the further reductions needed to meet bay water quality standards, overland
runoff from shoreline areas draining directly to tidal waters must also
be controlled.

     8.  Extensive sewering, with resultant lowering of water levels, and a
reduction in the pace of development in  Nassau  County will tend to reduce
runoff pollution without further planning and control, and may help to  solve
Nassau's runoff problems.  However, active planning and control is needed in
Suffolk,  because increasing development  in the  eastern portion of the  county
will increase pollutant loadings to runoff and  the  bays.


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      9.   Direct  overland runoff, which appears to contribute approximately
 40%  of  the  bacterial loading to the bays in Nassau County and 25% In Suffolk
 County,  is  generally not amenable to the same type of control that is effective
 in a stream corridor.

     10.   The original 208 surveys and stormwater sampling implicates dogs as
 the  primary contributors of coliform bacteria to surface waters.  Preliminary
 examination of NURP fecal coliform-fecal streptococci ratios support this
 finding.

     11.   There is evidence that large waterfowl populations on ponds contribute
 a significant  portion of the total colifonn load to the ponds; small populations
 do not.   Opportunities  for control are limited.

     12.   With  little remaining vacant land and, hence, few opportunities for
 additional  development, changes in land use in Nassau County over the next
 twenty  to thirty years will not have a significant impact on pollutant load-
 ings in  runoff.   Similarly, there is expected to be little if any change in
 western  Suffolk.  Loadings from land in Brookhaven and points east, how-
 ever, are expected to increase with projected increases in development.

 B.   GROUNDWATERS

      1.   The practice of collecting urban stormwater runoff in recharge basins
 and  allowing it  to infiltrate to the groundwater does not appear to constitute
 a threat to the  quality of the groundwater resource on Long Island.

      2.   Bacteria carried by runoff do not seem to reach the water table via
 infiltration.  Removal of total coliform, fecal colifonn and fecal streptococci,
during infiltration to the water table, is virtually 100%.

      3.   Heavy metals are reduced by infiltration by several orders of mag-
 nitude,  down to  detection limits.

      4.   There seems to be no adverse impact on groundwater from nitrogen
 in runoff,  but it is difficult to tell since nitrogen from other sources
 is almost always found in groundwater.

      5.   Chlorides seem to be totally unaffected by filtration and seem to  .
 pass freely through the unsaturated zone.  Low median concentrations were
 found at  all sites except the Huntington parking lot.

      6.   A  limited number of priority pollutant analyses indicates that
 priority  pollutants in stormwater and groundwater are below the recommended
 limit of  10ug/l  with 2 exceptions:  1,1,1-trichloroethane in Huntington,
 and  4.4-DDT in Plainview.

      7.   Most basins appear to be functioning satisfactorily, and in fact
 most seem to be  over-designed.  No special maintenance seems to be required.
                                  E4-11

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                       IV.  FURTHER INVESTIGATIONS

     Useful further Investigations would Include the Instrumentation and evalu-
ation of recharge basins draining other land-use types, more extensive analysis
of stonnwater and groundwater for priority pollutants, and analysis of water
and/or sediment in the unsaturated zone beneath the recharge basins to determine
 how and where the removal of  certain stormvater constituents occurs.   Addi-
 tional  computer modeling of rainfall-runoff relationships would  be extremely
 useful  in  the prediction and  evaluation of direct  runoff constituent  loadings
 to  Great South Bay.

      Investigations  to permit the  refinement of pond  modification  designs  for
 increased  detention  of runoff and  enhanced bacterial  dieoff appear likely  to
 yield significant benefits.

      Continuation and  possible  expansion of the NURP  salmonella  study should
 be  helpful in addressing the  question of an appropriate standard for  the cer-
 tification of shellfishing areas.   Inasmuch as  Long Island runoff  sampling
 suggests that a large  part of the  coliform loading is of non-human origin, it
would seem useful to look for the  presence of human pathogens rather  than  in-
 dicator organisms before closing shellfishing areas.   The.salmonella  study is
 expected to complement an on-going Suffolk County  study of the concentrations
 of  bacteria and other  pathogenic organisms in the  water column and in the  meat
 of  shellfish.
                                E4-12

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NATIONWIDE URBAN RUNOFF PROGRAM

      BALTIMORE REGIONAL
      PLANNING COMMISSION

         BALTIMORE, MD

        REGION III, EPA
           E5-1

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 I.  Project Location:

     Baltimore City/County, Maryland

II.  Project Description:

     A.  Urban Runoff-related Problems Observed

         The Jones Falls Urban Runoff Project (JFURP) has observed a range
         of possible problems through both its receiving waters and small
         catchment sampling.  If a water quality "problem" is described by
         EPA's three level definition, the observations may be interpreted
         as follows:
         Violation of State Standards - During storm runoff, receiving waters
         stations have exhibited violations in turbidity and fecal coliform
         bacterial indicators.  Dry weather,  base-flow conditions have also
         shown periodic bacterial violations.  Priority pollutant sampling
         has not been implemented for comparison with new state pesticide-
       •  standards.   Small homogeneous catchments., as well as receiving water
         stations downstream of more urbanized areas have exhibited some
         heavy metals event mean concentration levels that exceed EPA cri-
         teria; lead concentrations, for example.  No state standards pre-
         sently exist for nutrients, although event mean concentration values
         for total phosphorus seem to be significant.

         Denial or Impairment of Beneficial Use - Data collected to date (11/81)
         has not identified a direct denial or impairment of beneficial uses.
         For example, children are periodically seen playing and wading in the
         Stony Run stream, where fecal coliform levels have been documented at
         levels greater than 10  MPN/100 ml_,  with no apparent ill effects.

         Public Perception of a Problem - Communications with various publics
         in the watershed have not yet revealed a true perception of a pro-
         blem in the Jones Falls.   However, two problems related to urban runoff
         have been identified by the public:   localized flooding and rapidly
         eroding streambanks.  In the past, private citizens have been suf-
         ficiently concerned about the aesthetics of the Jones Falls and its
         tributaries to sponsor massive one-day clean-up campaigns.

     B.  Where
         Bacterial violations have been observed at all three receiving stream
         stations - both up and downstream of the urban area.  The five small
         homogeneous catchments, ranging in land use from low to high density
         residential and mixed residential-commercial,  have all exhibited vio-
         lations.

         Severe streambank erosion has occurred along both the Western Run and
         Stony Run tributaries and the Jones  Falls mainstream.   Most noticeable,
         however, is the Western Run which was subjected to intensive rainfall
         and resultant flooding in 1977 from  Hurricane David.
                                          E5-2

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      C.  How Often

          Analysis of data is not complete at this time.

      D.  How Severe

          Analysis of data is not complete at this time.

      E.  Under What Circumstances

          Analysis of data is not complete at this time.

      F.  Local Legal and Political Implications and Public Attitudes

          Through the past 208 Water Quality Management Planning process,
          member jurisdictions and the private sector have become more aware
          of problems in the region's waters and that nonpoint sources
          (including urban runoff) may be a major contributing factor.  As the
          emphasis has shifted from planning to implementation, certain pro-
         • grams are being changed or initiated to better reflect water quality
          objectives.  However, the earlier 208 studies only identified the pre-
          sence of nonpoint sources and a possible relationship to resulting
          problems.  A definitive quantification and description of urban runoff
          quality and its effects in receiving waters has not been determined.
          In the highly developed urban areas where urban housekeeping manage-
          ment practices seem to be more feasible then structural controls,
          local governments believe their present levels and types of practices
          are adequate.   Also, with present economic limitations, an increase
          in practice applications may not be justified when compared to other
          governmental needs.  Perhaps the "best" management strategy achievable
          will be one in which the application of current management practices
          will be optimized with some attendant positive results in water quality.
          JFURP results, both in pollutant contributions, effects and "best"
          methods of control, should better define the balance needed in water
          quality objectives achievement and increased or modified costs.

      G.  BMP's Investigated
          During the JFURP Study, a range of BMPs are being investigated.  These
          include an old water supply impoundment (60 acres), now a recreational
          lake, and a range of non-structural urban housekeeping practices.
          Inputs,  outputs, and lake quality are being monitored to determine its
          effectiveness  as a detention structure.  Housekeeping practices under
          study include  manual and mechanical street/alley cleaning,  storm inlet
          maintenance, domestic animal litter control,  and general sanitation
          practices.

          1.   Effectiveness of BMPs - not available at this time

          2.   Costs of BMPs - not available at this time

          E.   Problems - none so far

III.  Preliminary Conclusions Reached, Trends Indicated

      The level of data  analysis completed at this time does not allow preliminary
      conclusions or trends to be reached.
                                         E5-3

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IV.  Further Investigations Indicated - none at this time.   Additional data
     collection and analysis may reveal the need for further investigations.
                                       E5-4

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NATIONWIDE URBAN RUNOFF PROGRAM

 NORTH CAROLINA DEPARTMENT OF
      NATURAL RESOURCES

      WINSTON-SALEM, NC

       REGION IV, EPA
           E6-1

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I.    Project Location

     The Winston-Sal em NURP project is located in Winston-Sal em, North Carolina,
     in the county of Forsyth.

II.   Urban runoff related problems observed

     There are two major tributaries draining the county, Muddy Creek and
     Abbott's Creek;  both streams drain into the Yadkin River,  a major source
     of drinking water for many communities downstream.  Both  Winston-Salem
     study watersheds are in headwater areas of Muddy Creek.   A major portion
     of the urban area drains into Salem Creek, a tributary of Muddy Creek,
     upstream of High Rock Lake.

     The Muddy Creek  watershed  was monitored to determine its  importance to
     water quality in High Rock Lake, a lake downstream of the confluence of
     Muddy Creek and  the Yakdin River (High Rock Lake Study,  Weiss).  Between
     October 1977, and September, 1978, seventeen (17) river  sampling points,
     which defined fifteen (15) discrete subbasins and twelve  (12)  lake lo-
     cations were systematically sampled at a three week interval.   Thirty
     (30) different water quality parameters were analyzed and defined in each
     sample.

     Utilizing the total area for each subbasin as derived from a land use
     analysis (6IRAS  maps), the average daily yield of the principal water
     quality parameters was calculated for each of the Yadkin  subbasins.  The
     relative magnitude of these yields can be assessed by comparing the
     Upper Yadkin (Station 1) draining approximately 4900 Km   with  that of
     Muddy Creek (Station 2) draining 684 Km .  In the seasonal period of April-
     Noyember the Kjel-Nitrogen yield of the Upper Yadkin was  2596  grams/day/
     Km  whereas 684  Km  of the Muddy Creek subbasin produced  10,610 grams/
     day/km .  Maximum seasonal yields for phosphorus were generated from the
     Muddy Creek subbasin.  Of  the heavy metals zinc has the  highest yield at
     stations 2 and 1 (320 and  209 g/d/Km , respectively).  Mercury wasJiighest
     (3.6 g/d/Km ) at Abbotts Creek followed by Muddy Creek (2.1 g/d/KnT),
     Chromium in Muddy Creek (484 g/d/Km ) and the main river  (238  g/d/Km ),
     were highest as  was arsenic (289 g/d/Km ) in Muddy Creek  and the main
     river (176 g/d/KnT).

     The effect of changes in river flow on yield was further  examined by
     comparing the ratio between maximum and minimum mean yields at the same
     station for each of river  flow categories.  From further  analysis it was
     clear that Muddy Creek was exporting water degrading parameters at a
     rate several times or even orders of magnitude greater than the next
     largest exporter.

III.  How often and how severe

     Information on how often and how severe urban runoff problems  are has
     not been developed at this time.
                                       E6-2

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                                  -2-


IV.   Under what circumstances

     Although within the NURP project this has not yet been determined,  some
     inferences can be made from the 208 Urban Water Quality Management  Plan.
     The N.C. 208 Program collected and analyzed limited data in Winston-Salem.
     For instance, mercury concentrations considered "problematic"  (problematic
     is defined here as a concentration above the state water quality standards)
     occured more during low flow conditions than high flow (45% of samples
     taken during low flow versus 13% of samples taken during high  flow).   Lead
     and iron "problem" concentrations occurred in 100% and 92% respectively of
     the samples taken during high flow and 13% and 15% respectively of  the
     samples taken during low flow.  Pollutant concentrations were  generally
     higher in the CBD than in the residential watersheds monitored.

V.    Local, legal and political  implications and public attitudes

     Public attitudes toward urban runoff and/or the NURP project have been
     mixed.  The project has received quite a bit of support from a segment
     of the area public; however, it has been a controversial issue also.   It
     seems, even though there have been numerous efforts at public  involvement,
     the general public remains unaware of stormwater runoff's environmental
     impacts.

VI.   BMP's investigated

     Street sweeping and catch basin cleaning are the BMP's being tested in the
     Winston-Salem study.  Much of the data is still to be collected or  stored
     on computer, therefore, the following BMP discussion is preliminary.

     Effectiveness of BMPs

     Street sweeping activities have been monitored in both residential  and CBD
     land uses for sweeper efficiency as well as water quality.  Also, street
     solids accumulation studies and sweeping program effectiveness have been
     investigated.  One preliminary observation is that the sweeper can
     actually add solids to an area being swept if the initial street solids
     loading is small enough.  This may be by breaking up larger particles
     into smaller ones, or by brush wear or by dropping solids picked up
     elsewhere.  The trend that seems to be developing is the larger the
     initial load the better the removal of total street solids.  Removals
     have been seen up to 40%.  As expected, sweeping seems to be less
     efficient at the smaller particle sizes.

     Cost of BMP's

     Cost documentation is being prepared for both BMP's tested.  During the
     cost document formulation we found various factors that influence cost
     and should be acknowledged in street sweeping program review.   Among  these
     are: (1) distance to dump area, (2) age and type of equipment, (3)  age and
     type of road surface, (4) seasonal influences (leaf, snow, etc.), (5)
     distance to site.  These and other factors (unless adequately identified)
     can make cost and program comparisons extremely difficult.  Average total
                                       E6-3

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                             -3-
costs for residential street sweeping were determined to be $10.30/curb
mile, and for CBD total cost was $6.41/curb mile (MRI Document, K. Rife).
Average operating speed for the CBD is 4.7 curb miles/hour.  For the
residential average speed is 3.00 curb miles/hour.- Cost effectiveness
analyses will be included in the final report.

Problems

A complete problem description concerning street sweeping will  be included
in the final report.  Presently the only problems noticed are:  (1) initial
data indicates that sweepers are not that effective on the small particle
sizes, (2) regenerative air vacuum sweepers use water sprayers  to control
dust; however, vacuum sweepers freeze up when air temperature falls below
40°F.  Catch basin cleaning has not proven to be an effective BMP for
several, reasons.  First, most cities in N.C. have no catch basins they
have drop inlets or junction boxes.  This eliminates the detention treat-
ment techniques.  Since the outlet pipe is at the bottom of the tank, no
settling occurs.  These devices serve the purpose the city needs by elimi-
nating clogging of drainage pipe.  Quite a bit of manpower and  resources
go into cleaning of catch basins in Winston-Sal em.  They are cleaned on
two schedules once per year and/or emergency stoppage.  Therefore,
problem catch basins are cleaned more frequently than the average ones.

Problems occur when the catch basins are cleaned and the cleaning equipment
takes a lot of water into a holding tank which has to be emptied period-
ically.  Emptying it in a sanitary sewer instead of a storm drain or
creek bed would be more suitable.

Analysis of actual catch basin data has not begun.
                                 E6-4

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     NATIONWIDE URBAN RUNOFF PROGRAM



TRI-COUNTY REGIONAL PLANNING COMMISSION



              LANSING, MI



             REGION V, EPA
                  E7-1

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I.    Project Location

     Michigan,  Ingham County, Lansing

II.   Project Description

     Recent monitoring efforts along the Grand River have documented the
     existing water quality, and identified nonpoint source pollution as a
     major contributor to biochemical oxygen demand, nitrogen and suspended
     solids.  Fish ladders have been installed downstream at barriers which
     now permit salmon migration upstream into the Lansing area.   With this
     potential  recreational  opportunity being realized presently, the public
     attitude,  and that of the local governing bodies is strongly in favor
     of reducing pollution from urban nonpoint sources.

     The Bogus  Swamp Drain Drainage District was selected as a location where
     three alternative types of best management practices could be implemented,
     and their  effectiveness evaluated.  They include an in-line wet retention
     basin, two in-line up-sized (increased volume)  lengths of storm drain,
     and an in-line dry detention basin.

     Estimated  cost of the wet retention basin with  a runoff storage capacity
     above normal  level of 83,000 cubic feet, is approximately $173,000.

     The. incremental costs for the increased diameter sections of storm drains
     (above that of the normally sized drains) totalled  approximately $36,000.
     Pipes were 96 inch diameter, instead of 54 inch (needed for flow), and
     were 144 ft.  and 85 ft. in length.

     The remaining BMP is an existing depression comprised of several back
     yards, which  floods on occasions when the existing  drains prove inade-
     quate to handle the total flow, which subsequently  discharges the
     excess back into the storm drains, as the flows decrease.  No costs have
     been developed for this existing condition.

     Problems were encountered in scheduling the project in conjunction with
     the construction efforts required.  Also, when  sampling and  monitoring
     were initiated, sanitary flows from illicit connections had  to be
     corrected, along with improperly discharged industrial wastes.

III.  Preliminary Conclusions Reached; Trends Indicated

     Evaluation of the in-line wet retention basin has proved that it is very
     effective  in  retaining suspended sediment, total  phosphorus, total
     Kjeldahl nitrogen, biochemical oxygen demand and lead.  Efficiency of
     retention  increases with an increase in storm size, based on data for
     the sizes  of  storm evaluated.

     Results of evaluation of the in-line upsized storm  drain sections have
     shown highly variable performance.  One tentative conclusion is that
     the shorter section is probably too short for suitable settling times,
     given the  small particle sizes encountered.  The longer section has
     proved to  be  more effective in reducing sediment loads, and  pollutants
     associated with them, although less effective than  the wet retention
     basin.

                                     £7-2

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     The results  obtained  from  the  normally dry detention  basin  are  still
     being  evaluated,  as event  sampling  was initiated  later  for  this  BMP.
     A very preliminary look  at early  results  indicates  that while  it operates
     effectively  for  flood control,  its  effectiveness  in reducing pollutants
     is poor.

IV.   Further Investigations Indicated,  In  Pursuit of Answers to  Original
     questions and  Concerns'

     Given  the difficulty  of  locating  space in urban settings for in-line  wet
     retention basins  like that investigated, the use  of up-sized in-line
     storm  drains to  serve a  similar purpose needs  further evaluation.  A
     longer length  than either  of those  evaluated,  and locations providing
     opportunities  to  evaluate  different loading conditions,  and over a range
     of storm  events  for all  seasons,  is suggested  by  evaluation to  date.
                                 E7-3/E7-4 blank

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NATIONWIDE URBAN RUNOFF PROGRAM



     ANN ARBOR, MICHIGAN .



        REGION V, EPA
           E8-1

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I.    Project Location

     Michigan,  Washtenaw County,  Ann Arbor

11•   Brief Project Description

     A.    Urban Runoff Related Problems Observed

          Earlier water quality surveys disclosed  relatively good  water quality
          conditions during dry weather flow,  with dramatic  increases in pollu-
          tant  levels being experienced during stormwater  runoff periods.   Water
          quality standards violations have resulted.

     B.    Where, etc.

          Studies identified the  reach of the  Huron River  between  the Argo and
          Geddes Dams as one of three problem  areas.   Nonpoint sources would be
          the primary source, since point source discharges  do not exist in this
          reach.

          Both  the community and  the State consider the river to be a recreational
          resource.   Many past studies have been conducted by the  University of
          Michigan,  located in Ann Arbor.  As  a result, there has  been consider-
          able  public awareness concerning the quality of  water in the Huron
          River.

     C.    BMP's Investigated

          Three BMP's have been investigated in this  project.  One was the
          Swift Run  wetlands.  This BMP has proved to  be very effective for the
          range of storm event sizes sampled,  for  removal  of solids and heavy
          metals.  The effectiveness of nutrients  removal  appears  to vary,
          depending  on seasonal conditions.

          The second BMP evaluated was the existing Pittsfield-Ann Arbor
          retention  basin, designed to function as a  flood control structure.
          It has proven to be quite effective  in removal of  solids, and pollu-
          tants associated with them.  Appropriate modifications of the basin
          outlet structure, oriented towards water pollution control,  would be
          expected to improve the functioning  of this  BMP  in control  of runoff
          pollutants.

          The third  BMP was an on-line detention basin constructed adjacent to
          Traver Creek.  Although it will function as  an   off-line basin,
          while it was being monitored, it was operating as  an on-line BMP.
          It demonstrated only minimal removal of  pollutants, as tested.
          Construction delayed monitoring this project, and  not as many events
          were  sampled, as a result.

          Costs are  being developed for these  BMP's,  to be extent  possible,
          but are not yet available.
                                E8-2

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                                  -2-
III.  Preliminary Conclusions Reached  and Trends Indicated

     The flood control  wet retention  basin  in  the Pittsfield-Ann Arbor
     Drain has demonstrated, for the  range  of  events  sampled  and the seasonal
     coverage included, that water quality  benefits  are produced, also.   The
     Swift Run Wetlands are also effective  in  the removal  of  pollutants,
     subject (in the case of nutrients)  to  seasonal  variations.   The Traver
     Creek Drain BMP has proven less  effective, in part,  it  seems,  due to
     the upstream sources of contributions  (from a largely agricultural,  less
     intensively developed area).

IV.   Further Investigations Indicated in Pursuit of  Answers  to Original  Concerns

     Areas where further investigations  would  appear  to be fruitful  include
     the following:

     1.    For Traver Creek Drain,  the BMP needs to be evaluated  as  an off-line
          structure, with further testing as urban-development occurs.

     2.    For Pittsfield-Ann Arbor Drain, the  BMP should  be  evaluated after
          specific outlet structure modifications designed to improve pollu-
          tion control, are implemented.

     3.    The results obtained  during the evaluations described  above
          should cover a wider  range  of  storm  events, and  be conducted during
          all seasons to better understand  the effectiveness  variability that
          may result from different levels  of  runoff, during  the different
          seasons.
                           E8-3/E8-4 blank

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      NATIONWIDE URBAN RUNOFF PROGRAM

SOUTHEAST MICHIGAN COUNCIL OF GOVERNMENTS
         OAKLAND COUNTY, MICHIGAN

               DETROIT, MI

              REGION V, EPA
                    E9-1

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I.    Project Location

     Michigan,  Oakland County, Troy

II.   Brief Project Description

     The project was located in a relatively flat,  poorly drained and highly
     urbanized  area in southeast Michigan.   Experience had demonstrated
     evidence of poor storm-induced water quality.   In addition,  a network
     of rain gages was in place in close proximity.  Southeast Michigan Council
     of Governments studies have identified urban stormwater as an important
     factor in  water quality degradation.  This has become increasingly ob-
     vious as treatment of municipal  and industrial sources has been imple-
     mented in  the area.  Given the poor drainage conditions,  developers
     have been  required to provide normally dry detention basins  adequate
     for flood  control purposes.  Their design is such that they do not reduce
     pollutants included in urban storm runoff.

     Three of these on-line basins have been selected for modification to
     provide pollutant removal.  The project to date, has evaluated the pollu-
     tants and  concentrations prior to actual modifications to determine a
     base against which to compare results  following the basin modifications.
     Sampling for this purpose will be accomplished in the spring of 1982,
     now that modifications have been accomplished.  A problem of keeping all
     the monitoring and sampling equipment  operating during any given event
     has limited the usable data obtained during the initial phase.

     Legal and  institutional aspects of an  implementation program are under
     review as  well, and recommendations concerning needs in these areas will
     be another end product of this project.

III.  Preliminary conclusions reached

     Until the  event monitoring and sampling of the modified basins has been
     completed, and evaluation of results obtained  can be done, no conclu-
     sions can  be drawn.

IV.   Further Investigations Indicated in Pursuit of the Answer to the
     Original Question

     Other than a need to establish a much  larger data base, followed by a
     much increased sampling and monitoring program of modified structures,
     to include a wide range of storm events for all seasons,  it  is too soon
     to determine other potential investigative needs.
                                     E9-2

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      NATIONWIDE URBAN RUNOFF PROGRAM



NORTHEASTERN ILLINOIS PLANNING COMMISSION



               CHICAGO; IL



              REGION V, EPA
                 E10-1

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I.    Project Location;
     Glen Ellyn,  DuPage County, Illinois
II.   Project Description;
     A.    Urban runoff-related problem observed
          Algal blooms  and low dissolved oxygen (DO) levels.
     8.    Where
          Detention Basin
     C.    How Often
          Algae - Spring,  Summer and Fall.
          Low dissolved oxygen - Summer, occasionally.
     D.    How Severe
          Algae - blooms quite visible.
          DO - <  5 near the lake bottom.
     E.    Under What Circumstances
          Algae - almost any time.
          DO - quiet days, warm temperatures.
     F.    Local,  Legal  and Political Implications and Public Attitudes.
          No legal or political implications at present.   Public unconcerned,
          since principal  recreational  uses (ice skating,  aesthetics and
          fishing) are  not yet seriously impaired.
     G.    BMP's Investigated
          Wet bottom detention - effectiveness not  yet  calculated but thought
          to be about 90%  for suspended  constituents.  No  costs have been
          assembled yet.  No problems related  to the evaluation have been
          experienced.
III.  Preliminary conclusions reached, trends indicated
     Wet bottom detention  is very effective in removing suspended
     constituents for this particular case.  There  have been no con-
     clusions drawn yet concerning pollutant sources.  It  appears that
     about 75% of the load to the detention basin is less  than 63 microns
     in  size.  Little or no material is  being  retained  in  most catchbasins.
                                      E10-2

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                                  -2-


IV.   Further investigations indicated in  pursuit of answer to original
     questions/concernsT

     Further investigation is needed on the availability of constituent
     pollutants for uptake by benthic organisms.  There is concern that
     pollutant constituents in detention  basin sediments may become mobile
     and available to the water column under changing conditions of pH, DO
     or chloride,  as well as uptake by lake bottom benthic organisms,  and
     the potential for bio-accumulation in fish.  An additional  concern
     relates to the question of habitat,  and whether the limiting
     constraint on aquatic organisms is pollutant related or habitat
     related.
                             E10-3/E10-4 blank

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       NATIONWIDE URBAN RUNOFF PROGRAM

ILLINOIS ENVIRONMENTAL PROTECTION  AGENCY AND
    ILLINOIS STATE WATER SURVEY DIVISION

               CHAMPAIGN, IL

               REGION  V, EPA
                 E11-1

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                              Project Location

Illinois, Champaign County, City of Champaign.


                            Project Description

History of Urban Runoff Related Problems   .

Champaign was one of eight SMA's studied in the 1978 208 urban stormwater
assessment.  The urban assessment for Champaign indicated that general
water use standards are exceeded between 20-30 times a year for lead,
copper and iron.  The once a year maximum for these concentrations could
be 15-20 times higher than the standard.  Mercury was regularly observed
in stormwater samples and could be expected to exceed the standard 10
times a year.  Total suspended solids and total dissolved solids were
also frequently high.

Public Attitudes

During the 208 urban stormwater assessment an Urban Stormwater Task Force
composed of 8 local steering committees assessed the lEPA's study.  The
Champaign local steering committee concurred that there was an urban
runoff pollution problem but felt additional data was necessary to
determine whether urban stormwater runoff was a detriment to fishable and
swimable water quality, whether current general use standards were
applicable to urban stormwater pollution, and the relative impact of
urban runoff in relation to other pollution sources.

The local s-teering committee strongly supported intensive monitoring of a
local basin to clarify the above issues.  In addition, the committee
supported less expensive BMP's such as optimized street sweeping,
monitored road salting and on-site runoff control ordinances.
                                    El 1-2

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Project Description

The Illinois NURP is evaluating the use of municipal street sweeping as a
BMP for the improvement of urban stormwater quality.  Eight major project
objectives are:

1.  To relate the accumulation of street dirt to land use, traffic count,
    time, and type and conditions of street surface.

2.  To define the washoff of street dirt in terms of rainfall rate, flow
    rate, available material, particle size, slope and surface roughness.

3.  To determine what fraction of pollutants occurring in stormwater
    runoff may be attributed to atmospheric fallout.

4.  Modify the ILLUDAS model (1) to permit examination of the functions
    determined in objectives 1 through 3.

5.  To calibrate the modified model on all instrumented basins.

6.  To identify sources of pollutants in the urban environment.

7.  To determine, if possible, the influence of deposition and scour in
    the pipe system on runoff quality.

8.  To develop accurate production functions and corresponding cost
    functions for various levels of municipal street sweeping.  (Bender
    et al. 1981)

Four basins have been monitored since 1979:  2 paired single family
residential land use basins and 2 paired commercial land use basins.  In
addition, a microbasin with a single curb inlet and no pipe flow is being
examined for the washout characteristics of surface flow.

All four basins are being measured for rainfall and runoff quantity and
quality, contribution by atmospheric deposition, street dirt load,
accumulation rates and particle distribution.  Concentration analysis is
being completed for lead, iron, copper, total suspended solids, chemical
oxygen demand, phosphorous, K-Nitrogen, nitrite, ammonia, chloride and
sulfate.  Eighty-three events have been monitored and 1663 samples
collected between November 1979 and July 1981.
                                    Ell-3

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BMP Investigated

Street sweeping in one of each paired basin occurred while the other
remained unswept.  In the summer of 1980 each experimental basin was
swept twice weekly.  As the study progressed, the frequency was switched
to once a week and the basin treatments were reversed so the original
control basins were swept and sweeping in the original experimental
basins terminated.  A three wheel mechanical sweeper was used for
sweeping.  Preliminary results for sweeper efficiency are presented below.
                    Removal Efficiency by Particle Size
                                                   PERCENT
Portion of Load

    TOTAL
Mattis South
(Commercial)

     23
REMOVED
   John
                                                                   North
  (Residential)

       36
>3350 microns
3350-2000 microns
2000-1000 microns
1000-500 microns
500-250 microns
250-125 microns
125-63 microns
<63 microns
24
24
25
26
25
18
6
6
61
36 .
39
36
25
15
10
-5
                      (Table from Bender et al. 1981)

Based on 1980 figures, it has been estimated that sweeping costs $13.89
per curb mile.  Proper percentages for parts replacement, major repairs,
fringe benefits and overhead were not calculated into the cost per curb
mile which has resulted in a curb mile cost which may be lower than
actual cost.  This information is currently being analyzed and a new
estimate of cost per curb mile is being calculated.  In a survey of 15
Illinois Municipalities, Public Work Departments estimated sweeping costs
of between $4.98 - 220.60 per curb mile.
                                   Ell-4

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                   • Preliminary  Conclusions  and Trends

An analysis of the 1980 basin load data indicates that sweeping twice a
week has a large impact on measured street, load.   Load was reduced
approximately 63% in the residential basin and 24% in the commercial
basin.

Limited analysis has been made on water quality data so no conclusions
about sweeper effect on pollution concentration can be made.  However,
there is an indication that sweeping in the residential basin may have a
negative effect on water quality because more material is washed off the
swept basin versus an unswept basin.  Additional  analysis on the other
basins must be made before conclusions can be made.
                           Future Investigations

Further analysis will be made to determine the effect of sweeping on
water qulaity by:  additional comparisons of runoff quality from swept  .
and unswept basins, from experimental basins before and after the
sweeping program was initiated and simulation with the Q-Illudas water
quality model.

The next phase of NURP will examine the effects of urban runoff on
receiving streams.  Water quality upstream and downstream of the City of
Champaign will be monitored.

                                 Reference

Bender, Michael G., Michael L. Terstriep, and Douglas C. Noel.  1981.
Second Annual Report.  Nationwide Urban Runoff Project, Champaign,
Illinois.  Evaluation of the Effectiveness of Municipal Street Sweeping
in the Control of Urban Storm Runoff Pollution.  Illinois State Water
Survey, Urbana, Illinois.  82 pp.

WBC:jk/sp/2377c,l-6
                              E11-5/E11-6 blank

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           NATIONWIDE URBAN RUNOFF PROGRAM

   WISCONSIN DEPARTMENT OF NATURAL RESOURCES AND
SOUTHEASTERN WISCONSIN REGIONAL PLANNING COMMISSION

                    MADISON,  WI

                   REGION V,  EPA
                     E12-1

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                   SUMMARY OF MILWAUKEE COUNTY NURP PROJECT
I.    Project Location

     Milwaukee, Milwaukee County, Wisconsin

II.   Summary of Findings:

     The purpose of this project is to characterize urban runoff,  to identify
     urban runoff contaminant problems, and to evaluate street sweeping as an
     urban runoff control practice.

     A.    Urban Runoff Water Quality:

          Several urban runoff contaminants have been observed at
          concentrations above that considered to be serious.   These include
          metals (lead, zinc, cadmium  and copper), suspended solids, and fecal
          coliform.  Nutrients and BOD were not found at excessive
          concentrations and were generally much lower than Wisconsin's
          guidelines for sewage treatment plants.

          The detemination of 'problem'  metal concentrations  is based on the
          proposed 'White  Book'  criteria published in the Federal  Register
          (V45, N231, November, 1900).  'Problem' concentrations were deemed
          to be the acute toxicity concentrations for freshwater aquatic life,
          "not to be exceeded at any time."  These maxima concentrations are
          locally dependent upon the hardness of the receiving waters (for the
          Milwaukee area, 250 ng/1  is  a representative value for average event
          flow hardness concentration).  The analyses to date  have been able
          to identify the location, frequency and extent of urban  runoff
          problems.  Circumstances under which these problems  occur, however,
          have not been identified, i.e., the effects of antecedent conditions
          and rainfall  characteristics on concentrations remains unknown.
          Lead:
              Acute toxicity concentration:   526 ug/1.    Thirty-six  (36)  and
              eighteen (10)  percent of the event mean  concentrations  at the
              commercial  and high density residential  areas  respectively
              exceeded this  concentration.  Small  percentages  (one  (1)  and
              four (4)) of the events at the medium density  residential  areas
              and the parking lots also exceeded this  concentration.
          Zi nc:
              Acute toxicity concentration:   687 ug/1.    Sixteen  (16)  percent
              of the events at the commercial  areas  exceeded  this
              concentration, as did one (1)  and two  (2)  percent of  the medium
              density residential  areas and  the parking  lots  respectively.
              There is presently insufficient data at the high  density
              residential  areas to make an evaluation of this contaminant.
                                       E12-2

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     Cadmium:
         Acute toxicity concentration:  0 ug/1.   This concentration is
         frequently exceeded at the commercial  areas and at Rustler (a
         parking lot), but not at the other areas.

     Copper:

     ,   Acute toxicity concentration:  52 ug/1.   This concentration is
         frequently exceeded at Wood Center (a commercial  area) but not
         at the other areas.

     Suspended Solids:

         Wisconsin does not have an ambient stream standard for suspended
         solids.  The State's guidelines for sewage treatment plant
         effluent however specify a maximum 30 day average of 30 nig/1,
         and a maximum 7 day average of 45 mg/1.   Seventy-five percent of
         all suspended solids event mean concentrations exceeded 30 mg/1,
         50 percent exceeded 67 mg/1, 25 percent  exceeded  150 mg/1, and
         10 percent exceeded 300 rng/1.  Concentrations at  the commercial
         areas and at Lincoln Creek (a high density residential area)
         greatly exceeded concentrations at the other areas.

     Fecal  Col iform:

         Wisconsin has a fecal coliform ambient stream standard such that
         not more than 10 percent of the samples  taken over a 30 day
         period can have fecal coliform counts that exceed 400 mpn/100
         ml.  Ninety percent of all of the urban  runoff samples collected
         exceeded this level, and twenty (20) percent exceeded 50,000
         mpn/100 ml.

     Based on a recent survey of 1,000 people in  the Milwaukee area,
     95 percent of the respondents believe that there are  significant
     water quality problems, but only 23 percent  believe that urban
     runoff is a significant pollutant source.  Less than  10 percent of
     the respondents objected to increased expenditures for nonpoint
     source pollution control.

B.   Street sweeping as an urban runoff control practice:

     The experimental design of the project incorporated traditional test
     and control design concepts, i.e., test areas, where  the sweeping
     frequencies varied between baseline and accelerated levels, and
     control areas where the frequencies were held constant at baseline
     levels.  There is considerable unexplained variability in urban
     runoff concentrations however.  Even under the control situation
     there exists extreme fluctuations in the data base, i.e., when
     paired test and control areas were swept at  the same  frequency,
                                E12-3

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          there were very inconsistent relationships between their respective
          event mean concentrations.  Given this poor signal to noise ratio,
          it is very difficult to extract meaningful information.  There was
          found to be no demonstrable, statistically significant impact of
          accelerated street sweeping on any water quality parameter.  Whether
          there was in fact no impact, or the impact was  minor relative to
          the noise, is indeterminable.

III. Preliminary Conclusion Reached:
           *               •
     The degraded condition of urban runoff poses serious threats to
     freshwater aquatic life and to human body contact recreation.  These
     threats arise from high levels of suspended solids and fecal  coliform
     draining from most urban areas, and of toxic metals from heavily
     developed commercial and (to a lessor degree) high density residential
     areas.  Frequent street sweeping was not found to be effective in
     reducing these contaminants.

IV.  Further Investigations Indicated:

     A major weakness in interpreting the impacts of high concentrations of
     contaminants lies in the inadequate understanding of on-site and
     synergistic impacts of high event-flow concentrations on aquatic
     organisms.  Although event concentrations can be compared to established
     or promulgated criteria, (generally set for low-flow conditions),
     extrapolating from those criteria to actual  in-stream impacts is a far
     more nebulous and uncertain affair.  Further research is needed to
     ascertain the actual in-stream impacts of high event-flow concentrations.


0948A
                                      E12-4

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NATIONWIDE URBAN RUNOFF PROGRAM



          METROPLAN



        LITTLE ROCK, AR



        REGION VI, EPA
            E13-1

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I.    Project Location:

     Little Rock,  Pulaski  County,  Arkansas

II.   Project Description:

     A.    Urban runoff-related  problems  observed

          Pollutants identified as contributing to  water  quality  problems  are
          excessive coliform  concentration,  low pH  and  dissolved  oxygen  levels,
          high phosphorous and  heavy metals  concentrations,  and violation  of
          the water quality standards  for BOD and suspended  solids.

     B.    Where, etc.

          Water quality problems related to  urban runoff  were  observed  in  the
          Fourche  drainage system, which includes a proposed public  use area
          in Fourche Bottoms, where present  poor water  quality (high bacterial
          counts)  precludes water based  recreation.   The  city, the county, the
          health department and the University of Arkansas at  Little Rock  are
          actively cooperating  to control flooding  and  upgrade water quality
          in the Fourche system.

          Water quality problems were  identified during the  first year  sampling
          program, conducted  to discover background conditions.   The second
          phase of the  investigation will include sampling to  evaluate  the ef-
          fectiveness of BMP's  that are  now  in place or being  installed.   The
          BMP's being checked are sodding and rip rap along  stream banks,
          gabions, channel clearing, vegetation, and low  water check dams.

III.  Preliminary conclusions  reached,  trends indicated

     BMP evaluation has not resulted in  any  conclusions being  reached or trends
     indicated, at this early time in  the project.

IV.   Further investigations indicated, etc.

     The project has not yet  progressed  to the stage where further investiga-
     tions can be  identified.
                                     E13-2

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     NATIONWIDE URBAN RUNOFF PROGRAM  .

TEXAS DEPARTMENT OF WATER RESOURCES AND
         CITY OF AUSTIN,  TEXAS

             REGION VI, EPA
                E14-1

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I.    Project Location:

     Austin, Travis County,  Texas

II.   Project Description:

     A.    Urban runoff-related problems  observed

          The results obtained so far indicate  that  high  fecal  coliform counts
          were the most  distinct  characteristic of the  runoff loadings  from
          both stormwater  runoff  and receiving  water stations.   Other  runoff-
          related receiving  water impacts  were  elevated levels  of alkalinity,
          TSS, ammonia,  total  phosphorus,  BOD,  and bacteria  in  the lake
          waters.  Ammonia concentrations  were  found to exceed  .5 mg/L  during
          several runoff events.   There  was  an  increase in water treatment
          cost for the  production of drinking water  which correlated with run-
          off events when  the  cumulative rainfall  volume  was  greater than one
          inch.  Town Lake (the most urbanized  receiving  water)  generally has
          bacteria levels  5  to 6  times greater  than  that  of  Lake Austin.  Dur-
          ing storm events,  this  variation is greater.  Also,  some heavy met-
          als (lead, zinc) and pesticides  (DDT  and metabolites)  have been
          found in significant levels in the sediments.

     B.    Where - N/A

     C.    How Often - N/A

   .  D.    How Severe -  N/A

     E.    Under What Circumstances  - N/A

     F.    Local Legal and  Political  Implications and Public Attitudes

          The local populace is very concerned  with  environmental  issues.
          These attitudes  are  concerned  with aesthetic  and environmental
          issues relating  to development in  the Austin  area.  Accordingly,
          the results of this  NURP  project will receive close scrutiny  from
          the Council, economic interests, and  the populace as  a whole.

     G.    BMP's Investigated

          As part of the local  NURP  study  we have  investigated  a stormwater
          detention basin  as well  as non-structural  controls  in  the form of
          three levels of  impervious cover.

          1.   Effectiveness of BMP's

               a.  Stormwater  Detention  Basin - The  basin under  investigation
               seems to  be somewhat  effective in removing TSS  (67%), and mar-
               ginally effective  in  removing ammonia (27%) and  TKN  (26%).  It
               is felt at  this  time  that insufficient data exists  to draw
               broad conclusions.
                                    E14-2

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          b.  Non-structural controls.   At the present time data indicate that
          the storm average concentrations of most pollutants seem to be about
          the same for each of the two  test watersheds given similar physical
          conditions.  However, data has shown that the total runoff volume
          (on a per acre basis) is significantly lower for the Rollingwood
          (low impervious cover -- 21%) watershed than for the Northwest
          Austin (high impervious cover -- 39%) watershed, hence the
          Rollingwood watershed contributes significantly less pollutant mass
          (Ibs/acre) than does the Northwest Austin watershed under similar
          physical conditions.

     2.   Cost of BMP's - not available at this time

     3.   Problems - The study ran for  only 7 months of data gathering (March-
          September), due to unexpected flood damage and equipment malfunc-
          tions, where it was originally designed to collect one year's data.
          As a result, seasonal variations cannot be accurately shown.  Also,
          inflow/outflow data at Woodhollow Dam.is rather sparse.

III. Preliminary Conclusions Reached, Trends Indicated

Characteristic runoff-related receiving water impacts were elevated levels of
alkalinity, TSS, ammonia, total phosphorous, BOD and bacteria in the lake
waters.  During the course of the receiving water study, it has been observed
that the short-term impact of the "conventional" pollutants on the Town Lake-
Lake Austin receiving waters has been limited both spatially and temporally.
The impact of the discharge plume from  the tributaries to the lakes has been
limited to those areas immediately downstream of the tributary confluence with
the receiving water and in near-shore areas of the lake nearest the tributary.
These effects also are limited from only a few hours to several days after the
storm event, depending on the parameter being examined and the strength of the
storm (intensity and duration).  Unfortunately, comparison with upstream dam
releases is not complete.  Native biota do not seem to be negatively impacted
by these discharge plumes.  Long term effects of runoff on the receiving
waters are still under investigation, and trends and conclusions cannot be
meaningfully determined at this time.

Conclusions may be reached regarding the stormwater monitoring program from
the data now available to the project.   It has been seen that the storm-
averaged concentration of most pollutants may be correlated rather well with
dry days between runoff events, as well as total volume of runoff and storm
intensity, in addition to other parameters.  In many cases this correlation
is quite good.  Equations are presently being developed to describe the storm-
averaged concentrations in terms of some of these parameters.  In addition,
runoff co-efficients also correlate very well with dry days between storm
events.  Peak fluxes (Ibs/hour) of COD, TOC, NH3~N, and Total P correlate well
with peak flows at the monitoring sites and the flux curves for most pollutants
tend to closely follow the general shape of their associated hydrographs.
There is a definite trend toward higher runoff coefficients with an increase
in impervious cover.  Medium density residential land use (39% impervious)
does produce a larger runoff pollutant  load than a low-density residential
                                    E14-3

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land use (21% impervious).   Neither developed watershed demonstrated signifi-
cantly higher concentrations of detected parameters  upon comparison, but were
significantly higher than the undeveloped control  watershed at Turkey Creek.

IV.  Further Investigations Indicated -

     A.   Continuation of sampling at the Woodhollow Dam site  to  get suffi-
          cient data for a  statistically significant determination  of its
          efficiency in removal  of pollutants.

     B.   A seasonal study  of the lake that takes  in fall  and  winter
          conditions.

     C.   A study of the bacterial levels from the tributaries and  the
          sources and types of contamination.
                                     E14-4

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   NATIONWIDE URBAN RUN-OFF PROGRAM  •



DENVER REGIONAL COUNCIL OF GOVERNMENTS



              DENVER, CO



           REGION VIII, EPA
               El 5-1

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                  DENVER REGIONAL URBAN RUNOFF PROGRAM

       Adams, Arapahoe, Boulder, Denver, Douglas and Jefferson Counties
The Denver region, situated at the foot of the Rocky Mountains, receives only
about 14 to 15 inches of precipitation each year. About one-third of this total
occurs as snowfall in the winter months.  The snows usually melt rapidly within
three to four  days. However, there may be one or two periods where the snow
remains on the ground for more than a week at a time.  Lead and other airborne
particulate matter will accumulate in this  pack but generally the snowfall will be
of significant water equivalent to provide  enough water during snowmelt runoff
to dilute the  concentrations of most chemical constituents so as not to pose a
problem in the receiving waters.  Salt  loadings are higher during  these periods,
as one might expect from street sanding and salting operations, but measured
chloride concentrations are considered not to approach problem levels  for aquatic
life in the streams.

During the remainder of the year approximately eight or nine inches of rain will
fall.  Two rainfall regimes are apparent:  1)  frontal systems in early spring and
fall which produce long, gradual, light rains; and 2) convectional systems,
summer thunderstorms characterized by localized heavy rainfall of short duration.
It is these high intensity rains in the late summer during low flow conditions
that produce  the greatest loads of contaminants. Atmospheric deposition during
long intervals between rains,  oftentimes for weeks at a time, has a chance to
build up large loads on the land surface.  This is exacerbated by dry soil con-
ditions , general windy conditions, and the agricultural and construction-related
activities occurring at the outskirts of the Denver region.

When the thunderstorms do occur,  the  high kinetic energy associated  with rain-
drop impact and overland flow carry the accumulated loads to the receiving waters
Data collected to date have shown that quantifiable relationships exist between
the total amounts of rainfall, effective impervious areas,  and storm loads for
selected constituents.  Unit area loading  rates are greater for basins  with a
large extent of imperviousness which in general is related to more intense urban
land use activities. The Cherry Creek basin, which encompasses the  greater
part of the rapidly developing downtown central business district, produces the
most nonpoint pollution compared to other tributary basins on a per area basis.
A good part of this basin is storm-sewered with direct hydraulic connections to
the creek,  which has a minimal base flow to begin with.  The Cherry Creek
basin can produce up to  25 percent of the  total storm loads measured at a down-
stream location on the Platte even though  it encompasses  only 13 percent of the
entire monitored area.

During late summer when streamflows are  low and temperatures are high,  there
is not enough base flow in the South Platte to dilute the incoming storm loads.
An order of magnitude increase, from around 300 to 3,000  cfs, will occur in the
Platte and the runoff response of the basin to rainfall is rapid.  It takes about
                                   E15-2

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two-tenths of an inch of rain to wet all the street and vegetated surfaces before
runoff will occur.  This is important because a large proportion of the total
annual rainfall  occurs as a number of these small rainfall amounts, or cloud-
bursts ,  added up together over the course of  a year. Another consideration occurs
during the month of May when the heaviest rainfall occurs (two to three inches
of rain). This coincides with high streamflow in the South Platte River due to
the snowpack in the mountains which  is melting at this  time of the year. A dilu-
tion effect can  occur during this period. This does not  occur during drought
conditions  as are prone to occur from  time to time and which  the region  is now
experiencing.  Most of the urban runoff related problems can be considered to
occur under conditions of low flow, high temperature and low dissolved oxygen
observed during late summer which are critical periods for the survival of fish.

When discussing the urban runoff "problem" it is important to define what actually
is meant by this term.   It is not difficult to describe the "effect": that quantifiable
loads of chemical constituents are generated during runoff events  and that they
move to receiving waters.  Defining the "impact" is a much more difficult task.
Intuitively the word impact refers to a condition adversely affecting public health
or the health of aquatic biota, if the latter is determined to be a desirable amenity
to preserve.  Another consideration is that the magnitude of a water quality
problem is  defined in terms of how "clean" we choose a desirable level of water
quality to be.  Clearly, a "problem" occurs only when the criteria we have
established has been exceeded more often than a predetermined  "acceptable"
number of times in a-given period.

The duration of the  exceedance is also important.  The potential exists  for a
problem to occur when considering the fishery potential of a stream.  The major
contaminants of concern are potentially toxic substances. Besides the  synthetic
organic  compounds, the dissolved forms of certain heavy metals,  such as lead,
zinc, and cadmium  could pose a problem for stream life and also public water
supply.  This is because the dissolved metals are  the biologically available form
of the metal, the one which is easily incorporated  into body tissues. Shock
loading  of water supply intakes from urban runoff is a potential concern and a
management strategy designed to avoid using intake water with high dissolved
metals would be advisable.  At this point in our investigation, it would be
difficult to assess the impact on stream organisms without an extensive literature
review of toxicity levels impacting sensitive endemic fish species present.  As
the dissolved metal loads occur during the first  part of storms and move as slug
loads downstream,  and considering durations on the order of a few hours of
exposure and the tendency for fish to avoid plumes  of toxic concentrations  of
dissolved substances, no conclusions can be drawn from the available data at
this time on the extent or severity of  the urban runoff impact on the South Platte
River.

Even though it cannot be specified at this time if there is a chemical pollutant
problem associated with urban runoff  in Denver, another interpretation might
connote that there is a physical problem.  The effect of sedimentation in the
stream channel must also be considered.  Much of the sediment transported during
runoff periods is clay-sized and remains suspended in the flow.  This component

                                  E15-3

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merely moves  through the system, whereas sand and silt are deposited in the
river channel during storm periods, although scour of the bottom materials is
also occurring.  The impervious areas accumulate dry depositional materials
which eventually are worked into the streams.  Since major flood control structures
have been built on the mainstem of the Platte and also on its major tributaries
at the periphery of the urbanized Denver area, no large events are allowed to
really scour the channel and both  point source and nonpoint source sediments
accumulate over time.  These sediments  have the potential to continually inter-
act with the overlying water column depending on physical conditions of temper-
ature,   pH and redox which  control mobilization of heavy metals, for instance.
Current thoughts are that keeping  these materials out of the river might be
beneficial in that the channel substrate would be improved, and thus,  fish
habitat.  If the sediments are inactive then no chemical problem can be ascertained,
however, a physical problem might still exist.

Other potential problems are evident from the storm data collected to date.
Relatively high nutrient loads, mainly phosphorus  and nitrogen compounds, have
been observed to occur.  The interpretation is that accelerated eutrophication of
reservoirs, and other impoundments characteristic of water supply management
in the semi-arid west, can and will occur in waterbodies receiving this nutrient-
laden runoff.  If the reservoir is used for agricultural irrigation purposes, then
the nutrients might be considered beneficial, although the water-borne metals
could be detrimental, especially when they accumulate in the soil over the years.
If the reservoir is used for recreational purposes,  then bacterial pollution might
pose a problem as fecal material usually associated with the suspended matter
can reach into the hundreds  of thousands of colonies per 100 milliliters, far in
excess  of the suggested maximum of 2000 colonies/100 ml for secondary contact
recreation.  However, duration of exposure by humans could be effectively
managed to minimize recreational disturbances.

The Best Management Practices, or BMPs, which were investigated in  the Denver
project  include detention ponds and runoff ordinances.  Although street sweeping
with vacuum-type sweepers  is a possible BMP, it was considered  that this
management practice would  be very expensive.  Other studies have shown negligible
effect,  negative effect, or beneficial effects from  street sweeping.  High sweeping
frequency would probably preclude a cost-effective, energy-efficient approach.
Sediment control, by detaining storm flows, has promise although  maintenance of
facilities is a continuing cost.  Detention ponds built from scratch, retrofitted
flood retention ponds already in place, and rock-filled percolation pits seem to
hold promise as  BMPs for the Denver region. Another alternative is the creation
of wetlands  in low-lying areas. The wildlife and aesthetic amenities, as well as
natural  high contaminant-removal efficiencies of wetlands should be seriously
considered as well as negative impacts such as  pest control. Results from mon-
itoring a detention pond's effect on water quality are still being evaluated at the
present time.  As the water  quality problem is merely changed into a solid waste
problem,  disposal of pond sediments in an appropriate manner must also  be
considered.  Other considerations are the possible injuries  which  could be
associated with these structures,  and the delegation of maintenance responsibilities.

                                      E15-4

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This brings'us to the final considerations, those being the political and legal
implications. There exists an intrinsic value to having a waterbody close by
that people can enjoy, but assessing the dollar value ascribed to this is a
difficult matter.  Fish in the  river are desirable, but at what replacement cost?
What are the relative point and nonpoint effects on water quality, how can these
be differentiated, how can available funding for control measure  spending be  '
determined on a cost-benefit basis?  What flexibility exists for local governments
to spend federal funds on nonpoint control?  How is local financing generated?
What political entities should be responsible for implementing a  control program
should one be established?  Ultimately, what are the benefits to be accrued at
what costs?  Unfortunately,  answers to these questions cannot be determined  at
this time for the  Denver region, although they are being  pursued  and will be
addressed  in further analyses and deliberations on the matter.
                                 E15-5/E15-6  blank

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NATIONWIDE URBAN RUNOFF PROGRAM
        CASTRO VALLEY,  CA
         REGION IX,  EPA
              E16-1

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                                   SUMMARY
                            SAN FRANCISCO BAY AREA
                        NATIONAL URBAN RUNOFF PROJECT

                                      by
                        Gary Shawley, Project Manager
  I.  PROJECT LOCATION

      Castro Valley is a small, unincorporated community in Alameda County,
California, within the metropolitan San Francisco Bay region.  It is located
on the east side of San Francisco Bay, south of Oakland and north of San
Jose.  The project's primary test area is a natural, 2.4 square mile water-
shed which is considered typical of residential basins in the San Francisco
Bay region.
II.  PROJECT DESCRIPTION

      A.  Runoff Related Problems

          The San Francisco Bay-Delta Estuary is the single, most important
water body in California.  More than half of California's fishery resources
either live in or directly depend on the estuary for their survival.  It
also provides recreation to over five million people who live near its
shore.

          Stormwater-borne pollutants are thought to adversely effect the
water quality of San Francisco Bay, but a formal assessment of impacts is
difficult because the Bay drainage area is so large (about 3200 square
miles).  Although runoff contributes large amounts of pollutants, its
relationship to observed water quality problems remains uncertain.  The
primary use of many creeks in the Bay area is to convey stormwater runoff
to the Bay.  Castro Valley's creek's contribution of toxic pollutants
into the Bay is seen as a potential water quality problem.

          To determine whether improvements in water quality are necessary,
requires one to consider the beneficial uses of the receiving water.  In
Castro Valley Creek, the support of aquatic habitat is an established
beneficial use.  Table 1 compares EPA's aquatic life criteria with the
observed conditions in Castro Valley Creek for selected total  and dissolved
metals.  The table reports concentrations but does not consider the annual
loads delivered to the Bay.  Note that the maximum dissolved concentrations
are higher than the standards and that the total'concentrations also exceed
the maximum allowable concentrations.
                                    E16-2

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                                  TABLE 1

     Concentrations* of Selected Metals in Castro Valley Creek  Storm-
         water Compared to Water Quality Criteria for Aquatic Life


      Constituent    Aquatic Life Criteria        Castro Valley Creek
                                                Total         Dissolved
                     Maximum       Average  Max.  Average  Max.  Average

      Copper           0.04         0.006    0.7     0.1    0.35    0.05
      Lead             0.04         0.02    3.3     0.5    0.7    0.01
      Zinc             0.6          0.05    2.2     0.3    0.7    0.1

      *Units are mg/1, Castro Valley Creek water hardness = about 200 mg/1

     Two additional  problems in the Bay are thought to be linked to storm-
water runoff:

          o  Commercial and recreational shellfish harvesting is prohibited
             because of contamination from bacteria and heavy metals

          o  Fish kill  incidents can be traced to specific pollution  causes
             (although many fish kills in  the Bay occur for unknown reasons).

     The state is investigating the causes of death of striped  bass.   The
state may also initiate an aquatic habitat institute which will monitor the
effects of point and non-point discharges  on the bay biota.

     The public's awareness of and concern for Castro Valley Creek's'water
quality is not high because its primary use (and that of most other creeks
in the Bay area) is to convey stormwater runoff  into San Francisco Bay.  To
the extent that it exists, public perception of  a water quality problem
focuses on the Bay as a scenic, recreational and commercial water resource
for all communities within the Bay Area.   There  is widespread (and at times
vocal) citizen concern over water quality  of the Bay itself. The Bay  area
208 Study drew heavily upon public support and active citizen participation
in carrying out its problem identification tasks.  'However, the magnitude and
technical/institutional complexity of Bay  water  quality problems tend  to
discourage remedial  action by any one community.

     B.  Best Management Practice Investigated

         This project was conducted to develop information on the control of
urban stormwater runoff and the potential  impacts on water quality.  This
was the  first project to be part of EPA's Nationwide Urban Runoff Program
(NURP) and was designed to develop an understanding of the relationship
between street cleaning and urban stormwater runoff quality, using Castro
Valley Creek as the focus.  The scope of this project did not include  an
investigation of the effects of street cleaning  on the water quality  of San
Francisco Bay.  However, the project was based on the assumption that, if
street cleaning would improve water quality in Castro Valley Creek, then
street cleaning on a larger scale might improve  water quality in the  Bay.


                                   El 6-3

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          1.  Effectiveness

              Information on the urban runoff mass loading was compared
to the initial street surface loading values for each constituent.   This
analysis showed that up to 20 percent of the total solids and about 35
percent of the lead could have been prevented from reaching the creek.
Figure 1 illustrates this relationship and further shows that, after about
three passes per week, additional  street cleaning effort is unproductive.
If maximum urban stormwater runoff improvements are to result from  street
cleaning, then the streets should be cleaned during the winter months
between adjacent storm periods in the Bay area.

          2.  Costs

              Figure 2 shows that, after an initial  steep rise in unit
cost (i.e., from zero to twice-a-month street cleaning), the unit costs
actually decrease.  That is, the cost required to prevent a pound of
material from reaching the receiving water decreases.  After the frequency
exceeds about three times per week, however, the unit costs increase again.
If the program  costs can be justified in terms of water quality, then
cleaning three times a week between the winter storms may give the  best
return for the money for total solids.

          3.  Special Asbestos Study

              As part of this project, a special study of asbestos  was
conducted and it yielded some interesting results.  It was confirmed that
optical techniques are inadequate to identify asbestos in small quantities,
especially for small fiber sizes.   Also, about 10 percent of the runoff
monitored had detectable asbestos.  The asbestos fiber concentration in
urban runoff was about 30 million fibers per liter.   This corresponds
to 3 x 10   fibers per acre per year for an area without asbestos in
the natural soils.  Eighty percent of the street surface samples had
detectable asbestos fibers.  Street cleaning was found capable of removing
10% of the asbestos on street surfaces with weekly cleaning and up  to 50%
with cleaning three times per week.


III.   DESIGN OF STREET CLEANING PROGRAMS FOR WATER QUALITY

       Procedures were developed to calculate the effectiveness of  street
cleaning operations in improving urban runoff quality.  Simple tables and
figures were prepared in the project report to supplement this discussion.
These procedures can be used to develop street cleaning programs necessary
to meet runoff allocation goals, the most cost-effective unit removal  costs
or just the appropriation of available street cleaning dollars in the
service area.. They can also be used to determine when and where service
reductions should be made as decreasing budgets warrant.
                                   E16-4

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S3S
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       0  12
        Monthly
                     52
 104
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Motkly
 156
Hint
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tetkly
  208
Foul*
T1m
Mwkly
220
260
                           WMBH OF SHEET aEANING PASSES K» TEAR
                FIGURE  1.   IMPROVEMENT  IN URBAN RUNOFF QUALITY AS
                            A FUNCTION OF STREET CLEANING EFFORT
         g *4gs"«4

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      U.  S"0*
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                               X -Pounds Ptr Curb Rile Savtd Fron Rectlxlnq U«ttr
                               0 - OoUtr Ptr Pound Stvtd Fro* R»ct1»1ng toter
                               —AniuMl Cost
            *E
        u&ti5o.
             'as
         5o.
            r
                        (ton Oily
                      Quarttrly
                                   OEANIN6 FREQUENCT (PASSES PER TEAR)
              FIGURE  2.  UNIT COST  EFFECTIVENESS  OF CONTROLLING
                          URBAN RUNOFF TOTAL SOLIDS BY STREET
                          CLEANING
                                   E16-5/E16-6 blank

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NATIONWIDE URBAN RUNOFF PROGRAM



          BELLEVUE, WA



         REGION X, EPA
       E17-1

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The Bellevue NURP project is located totally within the limits of the City of
Bellevue, King County, Washington.

Project Description

The Bellevue drainage system relies on an extensive network of small streams
as a "trunk system" to convey Storm and Surface Water to the two large lakes,
Lake Washington and Lake Sammamish, bordering Bellevue to the west and east
respectively.  Major problems are solids and pollutant delivery into this
natural conveyance system and erosion and flooding within the conveyance
system.  These problems occur at some level almost continuously during our
seven-month winter rain season, with as many as half-a-dozen serious, signi-
ficantly damaging events per year.  There also have been sporadic fish kills
due to accidental spills and some indiscriminant dumping.  These problems have
been documented as largely responsible for serious deterioration in fish habitat
in the stream system.

Since the City's objective to manage the Storm and Surface Water System to
operate naturally (according to natural principles), the City relies on pollu-
tant source controls and regional and on-site detention as major controls.
The management practices being evaluated in Bellevue are street sweeping,
catchbasins and line maintenance, and detention.  Surrey Downs and Lake Hills
are two residential basins under study for street sweeping and conveyance
maintenance.  An urban arterial basin is being studied for detention as a
water quality control.

Since the 1960's Bellevue has been very interested in water quantity and
quality controls for its Storm and Surface Water System.  Several public
referenda have been held which resulted in the foundation of a Drainage
Utility in the mid-19701s and the sale of $10 million in revenue bonds in the
1980's for major capital improvements.  Strong public support has also
resulted in stringent erosion control regulations and enforcement, a salmon
enhancement program for Bellevue1s streams, and participation in NURP.
Bellevue volunteered, as part of a pilot program, to receive the first general
NPDES permit in the State for stormwater discharges.  Strong public and
political backing have been an essential part of Bellevue's progress in storm-
water management.  Bellevue plans to develop a comprehensive storm water
quality management program based on information generated through NURP.

Preliminary Results

Preliminary results indicate that street sweeping is not a effective measure
for stormwater runoff pollution abatement in Bellevue.  The best removals
seen to date have been 30%-40% and these are rarely achieved.  Even without
street sweeping for a 5-7 month period, accumulation is usually no more than
500-800 Ibs. solids/curb-mile in our experimental basins which is signifi-
cantly cleaner than other areas monitored in the country.  An intensive street
sweeping program of three times a week using a standard mobil sweeper rarely
reduces this load beyond 300-350 Ibs. solids/curb-mile.  During periods of
low loading, negative removals have been frequently observed.  This is
probably due to erosion of the street surface and/or broom, or possibly to
tracking in of material on the bottom of the sweeper from dirty areas.
                                  E17-2

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One reason for the low loadings is probably climate.   Rainfall  in Bellevue
occurs so frequently (approximately every two days in winter and every 4-7
days in summer) that before accumulation reaches a level where  sweeping could
be effective, rain effectively washes off the streets.  In addition, the street
sweepers do not operate well under continually damp street surface conditions.

Comparing street surface loads to storm loads, we have found that most of the
sediment material is not coming from the streets.  The only time street surface
material contributes significantly to storm loads is for small  storms (short
duration, low intensity).  For the larger storms, more off-street contri-
bution and more conveyance-system bedload movement is indicated.  We have
also found that solids loads are seasonal, with up to 50% of the total annual
solids loadings delivered in the months of November and December.  These loads
may be coming from erosion and/or washout of the systems bedload with the first
heavy seasonal rains.

Investigation of catchbasins revealed sediment loads ranging from 0.5-2.5 ft.
catchbasin.  This is greater than the street area contributary  to these catch-
basins but apparently little of this bedload moves once an "equilibrium" bed-
load has been established.  It was also found that street surface and catch-
basin sediment is comprised of similar constituents,  possibly implying a
similar source.  The constituents observed in the runoff, however, are signi-
ficantly different, possibly indicating different significant sources.

Preliminary Conclusions

In residential basins at least, street sweeping is probably of  little value
as a water quality control measure.  Since this appears to be based primarily
on area hydrology, street sweeping may be of little value in most areas (land
uses) in Bellevue except where these are extremely, high, instantaneous loads.
We hope to evauate other land use areas to test this preliminary conclusion
during the last phase of the project.  If sweeping is useful at all, it probably
would be in late summer and fall before the winter rains and before the salmon
return to spawn in Bellevue's streams.

Catchbasin and sewer cleaning may have some impact but more data and modeling
are needed.  Specifically it's necessary to investigate whether, if bedloads
were removed on a more frequent basis (just before when they reach equilibrium
allowing re-accumulation), significant improvements in runoff quality would
follow.  The City hopes to test this hypothesis during the last phase of the
project.  The data to date have clearly shown that sediment should be target
pollutant for control since most of the polluting material is associated with
solids.

In the last stage of the study, Bellevue will be looking more closely for
pollutant sources and controls not associated with streets.  That portion of
the study focussed on detention did not yield enough data to draw even preli-
minary conclusions at this time.  However, detention has the potential for
controlling both street and non-street pollutant sources, as well as water
quantitiy problems.  Several hundred of these systems are already installed
in Bellevue.  Therefore, Bellevue is very interested in the outcome of these
studies.
                                   E17-3/E17-4  blank

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        APPENDIX  F
PRIORITY POLLUTANT REPORT
            F-l

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                                  APPENDIX  F

                                   FOREWORD
     This appendix was prepared by the Monitoring and Data Support Division
of the EPA Office of Water Regulations and Standards.  Supporting contractors
were Dal ton-Dai ton-Newport, Cleveland Ohio and Versar, Springfield, Virginia.
Their preliminary findings of the NURP priority pollutant monitoring program
and special metals sampling project are presented.
                                      F-2

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     PRELIMINARY FINDINGS OF THE NURP
   PRIORITY  POLLUTANT MONITORING PROGRAM
             December 24, 1981
   U.S. Environmental Protection Agency
   Monitoring and Data Support Division
    Mr. Rod Frederick, Project Officer
Dr. Richard Healy, Work Assignment Manager

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                         CONTENTS
                                                      Page
List of Figures	   ii
List of Tables	iii
Preface	   iv

Section

    1.   Introduction 	    1

    2.   Methodology	    3

    3.   Findings	   10

    4.   Conclusions	   23
              Potential Risk to Human Health	   26
              Potential Risk to Aquatic, Life	   29

    5.   Special Metals Sampling Project	   31

References

Appendix
                         ^
    Appendix A - Land Use Characteristics of NURP
                 Priority Pollutant Sites
    Appendix B - Summary of EPA Ambient Water Quality
                 Criteria
    Appendix C - Pollutant Concentrations Reported in
                 NURP Runoff Samples
    Appendix D - EPA Water  Quality Criteria and Standards
                 for Toxic  Metals
    Appendix E - Special Metals Analytical Results
    Appendix F - Special Metals Quality Control Data

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                          FIGURES


Number                                                Page

    1    NURP Priority Pollutant City Locations ...     5

    2    NURP Special Metals City Location	    36


                          TABLES

    1    NURP Cities Collecting Priority Pollutant
         Samples	     4

    2    Summary of Analytical  Chemistry Findings
         From NURP Priority Pollutant Samples  ....    11

    3    Priority Pollutants Not Detected in NURP
         Urban Runoff Samples	    14

    4    Most Frequently Detected  Pollutants in
         NURP Urban Runoff Samples	    17

    5    Summary of Water Quality  Criteria Exceedances
         for Pollutants Detected in at Least 10 Per-
         cent of NURP Samples:   Number of Individual
         Samples in Which Pollutant Concentrations
         Exceed Criteria	    18

    5a   Summary of Water Quality  Criteria Exceedances
         for Pollutants Detected in at Least 10  Per-
         cent of NURP Samples:   Percentage of Samples
         in  Which Pollutant  Concentrations Exceed
         Criteria	    19

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Number                                                Page

    6    Non-Priority Pollutants Reported in NURP
         Urban Runoff Samples	    22

    7    Predominant Sources of Priority Pollutants
         Which Have Been Detected in at Least 10  Per-
         cent of Urban Runoff Samples 	    24

    8    Special Metals Project:   Parameter  List.  .  .    32

    9    NURP Cities Participating in the Special
         Metals Sampling Project.  ...  	    35

    10   Summary of Analytical Procedures Used  in
         the  Special Metals  Sampling Program	    37

    11   Summary of Number of Detections,  Mean
         Concentrations,  Range and Detection Limits
         for  Special Metals  Data  Collected as of
         October 1981	    41

    12   Summary of Water Quality  Criteria Viola-
         tions	    45

    13a   Total Recoverable and Dissolved Metals
         Concentration  as a  Percent  of Total
         Metals Concentration:  Priority Pollutant
         Metals	    46

    13b   Total Recoverable and Dissolved Metals
         Concentration  as a  Percent  of Total  Metals
         Concentration:   Non-Priority Pollutant
         Metals	    47

    14    Summary of Violations of EPA's "Red Book"
         Criteria for Non-Priority Pollutant
         Metals	    49
                            iii

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                          PREFACE
    The U.S. Environmental Protection Agency, Office of
Water Regulations and Standards (OWRS), is conducting pro-
grams to evaluate the environmental hazards posed by pri-
ority pollutants in our nation's waters.  The Monitoring
and Data Support Division of OWRS is coordinating a pro-
gram to determine the significance of urban runoff as one
source of toxic pollutants to receiving waters.  Specif-
ically, the objective of this program, the Nationwide Ur-
ban Runoff Program (NURP)  priority pollutant monitoring
effort, is to make a preliminary assessment of which pri-
ority pollutants are found in urban stormwater runoff, how
often, at what concentrations, and with what potential
impacts.

    The special metals sampling project is an additional
effort designed to enhance the usefulness of the NURP pri-
ority pollutant data base for metals, which are the pollu-
tants most frequently associated with urban stormwater
runoff.  The primary objective of the special metals proj-
ect is to determine the relationships among dissolved,
total, and total recoverable concentrations of selected
metals in runoff waters.

    The information developed through these efforts will
permit identification of problem areas nationwide and the
                             IV

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subsequent development of the most effective mitigation
strategies to correct urban runoff related problems where
necessary.  This report documents the preliminary findings
and results of the NURP priority pollutant and special
metals monitoring projects as of October 1981.
                            v

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                         SECTION 1

                       INTRODUCTION
    The Nationwide Urban Runoff Program  (NURP) priority
pollutant monitoring effort was initiated to evaluate the
significance of priority pollutants in urban stormwater
runoff.  The principal objectives of the program are (1)
to determine which priority pollutants are found in urban
stormwater runoff, how frequently,- and at what concentra-
tions, and (2) to evaluate the potential impacts of prior-
ity pollutants carried by urban runoff on aquatic life and
water supplies.  The information generated by this program
will .allow the Environmental Protection Agency's (EPA's)
Office of Water Regulation and Standards (OWRS) to assess
the significance of urban runoff relative to other point
and non-point sources of toxic pollutants, in order to
develop the most efficient and cost-effective control
strategies.

    The priority pollutants are a group of toxic chemicals
or classes of chemicals listed under Section 307(a)(1)  of
the Clean Water Act of 1977 (PL 95-217, U.S.C. 466 et
seq.).  There are ten major groups of priority pollutants
including 129 specific compounds or classes of compounds.

    The NURP priority pollutant monitoring program was
developed by EPA's Water Planning Division which provided

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grants to various urban localities for sample collection
and laboratory analysis.  EPA's Monitoring and Data Sup-
port Division (MDSD) is providing technical guidance con-
cerning sampling and analysis procedures, quality assur-
ance and quality control, processing of data, and inter-
pretation of results.  The NURP priority pollutant program
was developed as a logical extension of the NURP conven-
tional pollutant program, which is primarily concerned
with measuring concentrations of conventional pollutants
such as solids, phosphorus, nitrogen, and nitrates in ur-
ban runoff.

    With priority pollutant sampling activities now well
underway nationwide, this report presents preliminary re-
sults to date based on data which were available as of
October 31, 1981,  and offers some tentative conclusions
regarding program objectives.   Results are presented in
such a way as to be usable by  individuals whose concerns
are national, regional, or local in scope.  Obviously,
these are not final conclusions,  but observed trends in
the data.   Final conclusions must await completion,  veri-
fication,  and analysis  of  the  final data  base.

    This report  is  organized as  follows:

    Section 2 -  Methodology
    Section 3 -  Findings
    Section 4 -  Conclusions
    Section 5 -  Special metals project

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                         SECTION 2
                        METHODOLOGY
    Nineteen cities and metropolitan governmental councils
 (henceforth all will be referred to simply as "cities")
 are participating in the NURP priority pollutant monitor-
 ing program (Table 1).  The geographical distribution of
 these cities includes 11 of the 18 major river basins in
 the continental United States (Figure 1),  and ensures that
 a variety of climatic regimes and soil types are repre-
 sented in the sample population.  MDSD provided cities
 with the following general guidelines:

    1.   Use NURP sampling sites which are also being used
         for conventional pollutant sampling.

    2.   Use sites which have flow only when it rains. .

    3.   Take a flow composite sample for  the entire storm
         event.  Discrete samples can also be taken to de-
         termine concentration variations  during the storm
         event.

    Early in the program, participating cities attended an
MDSD-sponsored workshop in Springfield, Virginia.   Using
 the sampling guidance manual as a guide ("Monitoring of

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                          TABLE  1.


                        NURP CITIES
           COLLECTING  PRIORITY POLLUTANT  SAMPLES3
   1.   Durham,  New Hampshire
  *2.   Lake  Quinsigamond, Massachusetts
   3.   Mystic River,  Massachusetts
  *4.   Long  Island, New  York
   5.   Lake  George, New  York
   6.   Irondequoit Bay,  New York
   7.   Metro Washington, D.C.
   8.   Baltimore,  Maryland
  11.   Tampa,  Florida
  12.   Knoxville,  Tennessee
 *17.   Glen  Ellyn,  Illinois
 *19.   Austin,  Texas
 *20.   Little Rock, Arkansas
  21.   Kansas City, Missouri
 *22.   Denver,  Colorado
  23.   Salt  Lake City, Utah
 *24.   Rapid City, South Dakota
 *27.   Bellevue, Washington
 *28.   Eugene,  Oregon
* Asterisk indicates cities from which priority pollutant
  analytical data were available as of 10/31/81 in time to
  be included in this report.

a Numbering system conforms to NURP convention; some num-
  bers are omitted as not all NURP cities are collecting
  priority pollutant samples.
Toxic Pollutants in Urban Runoff:  A Guidance Manual"

[Versar, 1980a]), a number of issues were covered, e.g.,
sample collection procedures such as container selection,

container preparation, sample preservation, and shipping

procedures; and modification of conventional sampling
equipment for the collection of priority pollutant sam-

ples.  Extensive information on NURP guidance regarding
these and other relevant topics can be obtained from the

many sources which are listed in the References section of
this report.

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Ul
                                                                                0 SO 100  200  3OO
                                                                                          H
                                                                                          MILES
    Numbers identify major river basins
    delineated by the United States
    Geological Survey,  1980.
        : Priority Pollutant City
                           Figure  1. NURP Priority Pollutant  City Locations.

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     Samples  are  being  collected  from  approximately  70
 catchments which include  a varied  range of sizes/ popula-
 tions,  and land  use  types (Appendix A).  The  largest
 catchment, for example, collects runoff from  33,544 acres,
 the  smallest from but  a single acre.   The most common  land
 use  types are low-density residential, medium-density  res-
 idential, and commercial.  Land  use characteristics of the
 sampling sites were  obtained and recorded for use in fu-
 ture analyses, which will attempt  to  relate toxics concen-
 trations and loadings  to  site-specific land use and topo-
 graphic characteristics.

     Each participating city has made  appropriate labora-
 tory contracts for analytical services.  Six cities ar-
 ranged  for such  services  through a central EPA office,
 while the remaining  13 cities contracted directly with
 independent  laboratories.  Quality assurance  (QA)  proce-
 dures were established to ensure that the data developed
 from these many  cities and laboratories would be of high
 quality.  QA procedures are detailed  in "Quality Assurance
 for  Laboratory Analysis of 129 Priority Pollutants," (Ver-
 sar,  1980b),  and other NURP program documents.  Inasmuch
 as final QA/QC activities have not been completed,  all
 data  reported here must be considered preliminary.

     At  the time  of preparation of this report, priority
 pollutant analytical data were available from nine
 cities:  Lake Quinsigamond, Massachusetts;  Long island,
 New  York; Glen Ellyn, Illinois; Austin, Texas; Little
 Rock, Arkansas;  Denver, Colorado; Rapid City,  South
 Dakota; Bellevue, Washington;  and Eugene, Oregon.   A maxi-
 mum  of  68 sample results were available for the organic
priority pollutants and 46 sample results  for  the  inorgan-
 ics.  For some pollutants, the number of samples is less
 than the maximum because a pollutant may not  have been

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analyzed for in a particular sample or because some 're-
sults were withdrawn for quality control reasons.   The
data available for this report represent approximately one
half of the final data base expected.

    For the purposes of this program,  asbestos was not
analyzed due to high associated costs.  Dioxin was not
specifically analyzed for because of the health risk to
laboratory personnel involved.   Gas chromatograms  were
scanned for the possible presence of dioxin, however.

    The approach used to summarize and analyze the NURP
priority pollutant data is outlined below:

    1.    A complete listing of  the data was compiled for
         each pollutant which was detected, and identifies
         city,  site,  date of sample collection,  whether
         the sample was discrete or composite, pH, and
         measured pollutant concentration  (Appendix C).
         Important qualifying information concerning the
         analytical results was also noted.

    2.    Summaries of the data  were prepared for each de-
         tected pollutant including range of detected con-
         centrations, mean, number of  samples,, frequency
         of detection,  and concentrations of that  pollu-
         tant reported in other urban  runoff studies.

    3.    For those priority pollutants detected in 10 per-
         cent or more of the samples,  pollutant concentra-
         tions  in each undiluted runoff sample were compared
         to EPA water quality criteria and  drinking water
         standards (Appendix B).  Such a comparison provided
         an initial identification of  pollutants whose

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         concentrations in runoff could lead to potential
         violations of criteria or standards or adversely
         impact aquatic life or water supplies.

    4.   In a limited number of NURP samples, non-priority
         pollutants were also analyzed for and these re-
         sults are reported.  These non-priority pollu-
         tants are somewhat similar to priority pollutants
         in chemical form and should be considered for
         future work; however, specific analysis is beyond
         the scope of the current program.

    With reference to the above, some clarification is
worth noting.  In Step 2, the geometric mean rather than
the arithmetic mean is used,  as this is the appropriate
measure of central tendency when data are log-normally
distributed.  Such a distribution of NURP and similar data
has been demonstrated in the draft EPA Water Planning
Division report "Preliminary Results of the NURP Program"
(Athayde et al., 1981), and other runoff studies.

    Calculating an exact value for the mean (geometric or
arithmetic) is impossible, however, when some results are
"not detected" and therefore  unquantified.  What can be
done in this case is to calculate two geometric means,
which determine a range within which the actual mean
should fall.  The upper end of this range is calculated by
substituting the reported (or nominal)  detection limit in
the case of an "undetected" result.  The lower  end is cal-
culated by substituting one tenth of the detection limit
(although in no case a value  less than 0.001)  for  an unde-
tectable result as a substitute for zero,  which cannot be
accommodated in geometric mean calculations.  This range
bracketing the geometric mean was not calculated if more

-------
 than  85 percent of the sample results were "not detected,"
 due to the preponderance of unknown values.

    With regard to Step 3, several EPA water quality cri-
 teria were used.  Criteria for the protection of aquatic
 life  are of two types:  (1) the freshwater "acute" crite-
 rion, the maximum concentration of a pollutant permitted
 at any time; and  (2) the freshwater "chronic" criterion,
 the maximum 24-hour average concentration allowed.  If
 either the acute or chronic criterion has not been estab-
 lished for a pollutant, then the lowest reported fresh-
 water acute concentration or the lowest reported fresh-
 water chronic concentration was substituted.   Human health
 criteria include both a non-carcinogenic health criterion
 for the ingestion of contaminated water and organisms,  and
 a carcinogenic effects criterion at the 10~ ,  10~ ,
 and 10   risk levels for ingestion of contaminated water
 and organisms.   Human health criteria based on the inges-
 tion of contaminated organisms only were not used, in
order to apply the more stringent water and organisms
standards.   EPA also has criteria associated with taste
and odor problems (organoleptic  criteria)  as  well as
drinking water standards under the. Safe Drinking Water  Act.

-------
                         SECTION  3

                         FINDINGS
    Detailed NURP priority pollutant analytical results
including city and site where sample was collected,  date
of collection, discrete or composite sample, pH, and pol-
lutant concentration can be found in Appendix C.  Appen-
dix C also lists, for each detected pollutant, the range
of concentrations, geometric mean (if calculated), number
of samples, frequency of detection, and reported concen-
trations in other studies.   A concise summary of the cur-
rently available data base is presented in Table 2.

    The findings derived from this preliminary NURP  prior-
ity pollutant data base are:

    1.   Sixty-two priority pollutants were detected in
         urban runoff (Table 2);  65 were not found in any
         urban runoff samples (Table 3).   (Asbestos  is not
         included in the NURP program and results for di-
         chloromethane are not yet available.)

    2.   Thirteen of the 14 inorganic priority pollutants
         were found in urban runoff.   Most frequently de-
         tected were zinc,  lead,  copper,  and arsenic which
         were found in 100, 93,  91,  and 58 percent of the
                             10

-------
                                                         TABLE 2.

                                         SUMMARY OF ANALYTICAL CHEMISTRY FINDINGS
                                           FROM  NURP  PRIORITY POLLUTANT  SAMPLES a
                                     (includes information received through 10/31/81)
Pollutant
Frequency of Range of detected
Cities where detected*3 detection (%) concentrations (vg/1)
I. PESTICIDES
1.
2.
3.
4.
5.

6.
7.
e.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
Acrolein
Aldrin
o-Hexachlorocyclohexane ( o-BHC) (Alpha)
0-Hexachlorocyclohexane ( fr-BHC) (Beta)
Y-Hexachlorocyclohexane ( T-BHC) (Gamma)
(Lindane)
6-Hexachlorocyclohexane ( 6-BHC) (Delta)
Chlordane
ODD
DDE
DDT
Dieldrin
o-Endosulfan (Alpha)
8-Endosulfan (Beta)
Endosulfan sulfate
Endrin
Endrin aldehyde
Heptachlor
Heptachlor epoxide
Isophorone
TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin)
Toxaphene
Not detected
Not detected
22, 27 25 0.0027-0.9
Not detected

22,27 11 0.002-0.9
27 3 0.006-0.007
2 2 0.01
Not detected
Not detected
27 2 0.35
27 3 0.008-0.1
27 2 0.2
Not detected
Not detected
Not detected
Not detected
Not detected
Not detected
Not detected
Not detected
Not detected
II.    METALS AND INORGANICS

        22.  Antimony
        23.  Arsenic
        24.  Asbestos
        25.  Beryllium
        26.  Cadmium
        27.  Chromium
        28.  Copper
        29.  Cyanides
        30.  Lead
        31.  Mercury
        32.  Nickel
        33.  Selenium
        34.  Silver  •   '
        35.  Thallium
        36.  Zinc

III.   PCBs AND RELATED COMPOUNDS

        37.  PCB-1016 (Aroclor 1016)
        38.  PCB-1221 (Aroclor 1221)
        39.  PCB-1232 (Aroclor 1232)
        40.  PCB-1242 (Aroclor 1242)
        41.  PCB-1248 (Aroclor 1248)
        42.  PCB-12S4 (Aroclor 1254)
        43.  PCB-1260 (Aroclor 1260)
        44.  2-Chloronaphthalene

IV.    HALOGENATED ALIPHATICS

        45.  Methane, bromo- (methyl bromide)
        46.  Methane, chloro- (methyl chloride)
        47.  Methane, dichloro- (methylene chloride)

         d)
22
2,19,20,22,27
Not included in NURP program
20
2,20,22,27
2,17,20,27,28
2,17,19,20,22,27,28
4,19,22,27
2,17,19,20,22,27,28
20,28
2,20,22,27
19,22
17,27
Not detected
2,17,19,20,22,27,28
Not detected
Not detected
Not detected
Not detected
Not detected
Not detected
2
Not detected
Not detected
Not detected
Data not available
2
58

9
38
45
91
31
93
7
44
20
4

100
2
2-35

1-4
0.2-17
2-61
11-110
2-33
37.6-445
0.6-1.2
5-270
2-25
0.6-0.8

10-546
               0.03
                                                          11

-------
TABLE 2.   (Continued)
          Pollutant
                                                           Cities where detected15
                                                                              Frequency of
                                                                              detection (%)
  Range of detected
concentrations (ug/1)
IV.
       HALOGENATED ALIPHATICS
       (Continued)
V.
VI.
VII.
48.
49.
50.
51.
52.
53.
54.
55.
56.
57.
58.
59.
60.
61.
62.
63.
64.
65.
66.
67.
68.
69.
70.
Methane, chlorodibromo-
Methane, dichlorobromo-
Me thane, tribromo- (bromoform)
Methane, trichloro- (chloroform)
Methane, tetrachloro- (carbon tetrachloride)
Methane, trichlorofluoro-c
Methane, dichlorodifluoro-c (Freon-12)
Ethane, chloro-
Ethane, 1,1-dichloro-
Ethane, 1,2-dichloro-
Ethane, 1,1,1-trichloro-
Ethane, 1,1,2-trichloro-
Ethane, 1,1,2,2-tetrachloro-
Ethane, hexachloro-
Ethene, chloro- (vinyl chloride)
Ethene, 1,1-dichloro-
Ethene, 1,2-trans-dichloro-
Ethene, trichloro-
Ethene , tetrachloro-
Propane, 1,2-dichloro-
Propene, 1,3-dichloro-
Butadiene, hexachloro-
Cyclopentadiene, hexachloro-
28
28
28
4,17,20,27,28
4,20,28
2,4,24,28
Not detected
Not detected
4,20,28
28
4,17,20,22,24,26
4,20,28
4,20
Not detected
Not detected
28
20,28
4,20,28
4,17,20,22,28
28
28
Not detected
Not detected
ETHERS

 71.  Ether, bis(choromethyl)
 72.  Ether, bia(2-chloroethyl)
 73.  Ether, bis(2-chloroisopropyl)
 74.  Ether, 2-chloroethyl vinyl
 75.  Ether, 4-bromophenyl phenyl
 76.  Ether, 4-chlorophenyl phenyl
 77.  Bis(2-chloroethoxy) methane

MONOCYCLIC AROMATICS (EXCLUDING PHENOLS, CRESOLS,
PHTHALATES)
78.
79.
80.
81.
82.
83.
84.
85.
86.
87.
88.
89.
Benzene
Benzene, chloro-
Benzene, 1,2-dichloro-
Benzene, 1,3-dichloro-
Benzene, 1,4-dichloro-
Benzene, 1,2,4-trichloro-
Benzene, hexechloro-
Benzene, ethyl-
Benzene, nitro-
Toluene
Toluene, 2,4-dinitro-
Toluene, 2,6— ainitro
PHENOLS AND CRESOLS
90.
91.
92.
93.
94.
Phenol
Phenol, 2-chloro-
Phenol, 2,4-aichloro-
Phenol, 2,4,6-trlchloro-
Phenol, pentachloco-
                                                           Not detected
                                                           Not detected
                                                           Not detected
                                                           Not detected
                                                           Not detected
                                                           Not detected
                                                           Not detected
                                                           4,17,20,27,28
                                                           20,28
                                                           Not detected
                                                           Not detected
                                                           Not detected
                                                           Not detected
                                                           Not detected
                                                           4,17,20,28
                                                           Not detected
                                                           4,17,20,
                                                           Not detected
                                                           Not detected
                                                           20,27
                                                           20,28
                                                           22
                                                           Not detected
                                                           4,19,20,22,27,28
                                                                                           1
                                                                                           1.
                                                                                           1
                                                                                           24
                                                                                           6
                                                                                           9
                                                                                           9
                                                                                           2
                                                                                           35
                                                                                           8
                                                                                           9
                                                                                           3
                                                                                           12
                                                                                           1?
                                                                                           10
                                                                                           1
                                                                                           3
                                                                                    34
                                                                                    7
                                                                                    12

                                                                                    24
                                                                                    3
                                                                                    3
                                                                                    1

                                                                                    18
                                                                                                   2
                                                                                                   2
                                                                                                   1
                                                                                                   0.2-8
                                                                                                   1-2
                                                                                                   0.58-27
                                                                                                   1-5
                                                                                                   4
                                                                                                   1-23
                                                                                                   1-3
                                                                                                   1-3
                                                                                                   1.5-4
                                                                                                   1-3
                                                                                                   1-3
                                                                                                   1-43
                                                                                                   3
                                                                                                   1-2
      1-13
      1-3
      1-3

      3-9
      2-3
      2-22
      10

      1-115
 (continued)
                                                           12

-------
TABLE 2.   (Continued)
          Pollutant
Cities where detectedb
Frequency of     Range of detected
detection (%)  concentrations (vg/1)
VII.   PHENOLS AND CRESOLS (Continued)

        95.  Phenol, 2-nitro-
        96.  Phenol, 4-nitro-
        97.  Phenol, 2,4-Hnitro-
        98.  Phenol, 2,4-diraethyl-
        99.  m-Cresol, p-chloro-
       100.  o-Cresol, 4,6-dinitro-

VIII.  PHTHALATE ESTERS

       101.  Phthalate, dimethyl
       102.  Phthalate, diethyl
       103.  Phthalate, di-n-butyl
       104.  Phthalate, di-n-octyl
       105.  Phthalate, bis(2-ethylhexyl)
       106.  Phthalate, butyl benzyl

IX.    POLYCYCLIC AROMATIC HYDROCARBONS

       107.  Acenaphthene
       108.  Acenaphthvlene
       109.  Anthracene
       110.  Benzo(a)anthracene
       111.  Benzo(b)fluoranthene
       117.  Benzo(k)fluoranthene
       113.  Benzo(g,h,i)perylene
       114.  Benzo(a)pyrene
       115.  Chrysene
       116.  Dibenzo(a,h)anthracene
       117.  Fluoranthene
       118.  Fluorene
       119.  Indeno(l,2,3-c,d)pyrene
       120.  Naphthalene
       121.  Phenanthrene
       122.  Pyrene

X.     NITROSAMINES AND OTHER NITROGEN-CONTAINING
       COMPOUNDS

       123.  Nitrosaraine, dimethyl  (DMN)
       124.  Nitrosamine, diphenyl
       125.  Nitrosamine, di-n-propyl
       126.  Benzidi'ne
       127.  Benzidine, 3,3'-dichloro-
       128.  Hydrazine, 1,2-diphenyl-
       129.  Acrylonitrile
Not detected
4,20,28
Not detected
Not detected
4
Not detected
Not detected
17,20
4,20,22,24,28
20
4,17,19,20,22,28
Not detected
Not detected
Not detected
17,20,27
27
27
27
Not detected
27
17,27
Not detected
17,27
Not detected
Not detected
4,20,28
17,20,27
17,27
Not detected
Not detected
Not detected
Not detected
Not detected
Not detected
Not detected
      10
      5
      11
      2
      24
      6
      10
      7
                     1-19
                     1-2
1-5
2.8-11
1
1-41.5
                     1-S
                     1-3
                     2
                     4

                     1-2
                     0.6-4.5

                     0.3-12
1-13
0.3-7
0.3-10
8 Based on 68 organic and 46 inorganic sample results received as of 10/31/81,
  review.  Nine cities reporting.

D Citiee from which data are available:
       2.  Lake Quinsigamond, MA
       4.  Long Island, NY
      17.  Glen Ellyn, IL
      19.  Austin, TX
      20.  Little Rock, AR
      22.  Denver, CO
      24.  Rapid City, SD
      27.  Bellevue, WA
      28.  Eugene, OR
  Numbering of cities conforms to NURP convention.

c Recently removed from priority pollutant list.
                    adjusted for preliminary quality control
                                                           13

-------
                               TABLE 3.

                   PRIORITY POLLUTANTS NOT DETECTED
                     IN NURP URBAN RUNOFF  SAMPLES3
           (includes information received through 10/31/81)
Pollutant
                                                       Reported  limits
                                                        of  detection13
I.
      PESTICIDES
II.
III.
V.
VI.
1.
2.
4.
8.
9.
13.
14.
15.
16.
17.
18.
19.
20.
21.
Acrolein
Aid r in
6- He xachlor ocyc lohexane
ODD
DDE
S-Endosulfan
Endosulfan sulfate
Endrin
Endrin aldehyde
Heptachlor
Heptachlor epoxide
Isophorone
TCDD
Toxaphene
METALS AND INORGANICS
35.
PCBs
37.
38.
39.
40.
41.
42.
44.
Thallium
AND RELATED COMPOUNDS
PCB-1016
PCB-1221
PCB-1232
PCB-1242
PCB-1248
PCB-1254
2-Chloronaphthalene
IV.   HALOGENATED ALIPHATICS
                                                       100
                                                         0.003-10
                                                         0.004-10
                                                         0.012-10
                                                         0.006-10
                                                         0.01-10
                                                         0.03-10
                                                         0.009-10
                                                         0.023-10
                                                         0.002-10
                                                         0.004-10
                                                        10
                                                         0.5
                                                         0.4-10
                                                         1-63
                                                         0.04-10
                                                         0.04-10
                                                         0.04-10
                                                         0.04-10
                                                         0.05-10
                                                         0.5-10
                                                        10
45. Bromoraethane
46. Chloromethane
54. Dichlorodifluoromethanec
55. Chloroethane
61. Hexaehloroethane
62. Chloroethene
69. Hexachlorobutadiene
70. Hexachlorocyclopentadiene
ETHERS
71. Bis(chloromethyl) ether
72. Bis(2-chloroethyl) ether
73. Bis(Z-chloroisopropyl) ether
74. 2-Chloroethyl vinyl ether
75. 4-Bromophenyl phenyl ether
76. 4-Chlorophenyl phenyl ether
77. Bis(2-chloroethoxy) methane
MONOCYCLIC AROMATICS (EXCLUDING PHENOLS,
80. 1,2-Dichlorobenzene
81. 1,3-Dichlorobenzene
82. 1 , 4-Dichlorobenzene
83. 1,2,4-Trichlorobenzene
10
10
10
10
10
10
10
10

10
10
10
1-10
10
10
10
CRESOLS, PHTHALATES)
10
10
10
10
(continued)
                                  14

-------
TABLE  3.   (Continued)
                                                       Reported limits
                                                        of detection13
Pollutant
VI.   MONOCYCLIC AROMATICS  (EXCLUDING PHENOLS,
 (Continued)

      84.  Hexachlorobenzene
      86.  Nitrobenzene
      88.  2,4-Dinitrotoluene
      84.  2,6-Dinitrotoluene

VII.  PHENOLS AND CRESOLS

      93.  2,4,6-Trichlorophenol
      95.  2-Nitrophenol
      97.  2,4-Dinitrophenol
      98.  2,4-Dimethylphenol
      100. 4,6-Dinitro-o-cresol

VII.  PHTHALATE ESTERS

      101. Dimethyl phthalate
      106. Butyl benzyl phthalate

IX.   POLYCYCLIC AROMATICS

      107. Acenaphthene
      108. Acenaphthylene
      113. Benzo(g,h,i)perylene
      116. Dibenzo(a,h)anthracene
      118. Fluocene
      119. Indenod.2,3-c,d)pyrene
X.
CRESOLS, PHTHALATES)
         10
         10
         10
         10
         10-25
         10-25
         25-250
         10-25
         25-250
         10
         10
         10
         10
         10-25
         10-25
         10
         10-25
      NITROSAMINES AND OTHER NITROGEN-CONTAINING COMPOUNDS
123.
124.
125.
126.
127.
128.
129.
Dimethyl nitrosamine
Diphenyl nitrosamine
Di-n-propyl nitrosamine
Benzidine
3,3'-Dichlorobenzidine
1,2-Diphenylhydrazine
Acrylonitrile
10
10
10
100
10
10
100
8 Based on 68 organic and 46 inorganic sample results received as of
  10/31/81, adjusted for preliminary quality control review.   Nine
  cities reporting.

b Where more than one detection limit is applicable because labora-
  tory methodologies differed, a range is given.

c Recently removed from the priority pollutant list.
                                 15

-------
     samples, respectively (Table 4).   The maximum
     zinc concentration was 540 ug/1  and the maximum
     lead concentration was 445 ug/1.   Cadmium, chrom-
     ium, cyanides, nickel, and selenium were detected
     in from 20 to 50 percent of the  samples.  Four
     metals (antimony, beryllium, mercury, and silver)
     were found in less than 10 percent of the sam-
     ples.  Thallium was the only priority pollutant
     metal never found.

3.   Of the 113 priority pollutant organics (dichloro-
     methane excluded), 49 were found  in urban run-
     off.  Of these, six were found in 20 percent or
     more of the NURP samples:   o-hexachlorocyclo-
     hexane; trichloromethane (chloroform); 1,1,1-tri-
     chloroethane;  benzene; toluene; and bis(2-ethyl-
     hexyl)  phthalate.  The maximum reported concen-
     trations among these pollutants are 41.5 ug/1 for
     bis(2-ethylhexyl)  phthalate, 23 ug/1 for 1,1,1-
     trichloroethane, and 13  ug/1 for  benzene.   An ad- .
     ditional nine  organics were found in 10 to 19
     percent of the samples (Table 4).

4.   A comparison of individual sample pollutant concen-
     trations undiluted by stream flow with EPA water
     quality criteria and drinking water standards re-
     veals numerous exceedances of these levels, as shown
     in Tables 5 and 5a.  Table 5 displays the exceed-
     ances on a number of samples basis, while Table 5a
     converts this  information to a percentage basis.
     This analysis  was conducted only  for those pollut-
     ants detected  in at least 10 percent of the samples.
     Among the metals, copper exceeded its freshwater
     acute criterion in 69 percent of  the samples, while
     cadmium and lead each exceeded this criterion at least
                         16

-------
                                  TABLE 4.

                    MOST FREQUENTLY DETECTED POLLUTANTS
                       IN NURP URBAN RUNOFF SAMPLES3
              (includes information received through 10/31/81)
 Pollutants  Detected in 50%  or More of the NURP Samples
      Inorganics
                                 Organics
                                   None
23. Arsenic (58%)
28. Copper (91%)
30. Lead (93%)
36. Zinc (100%)
 Pollutants  Detected in 20%  to 49%  of the NURP Samples
      Inorganics
  26.  Cadmium (38%)
  27.  Chromium (45%)
  29.  Cyanides (31%)
  32.  Nickel  (44%)
  33.  Selenium (20%)
                                 Organics
                              3. o>-Hexachlorocyclohexane (25%)
                             51. Trichloromethane (Chloroform) (24%)
                             58. 1,1,1-Trichloroethane (35%)
                             78. Benzene (34%)
                             87. Toluene (24%)
                            105. Bis(2-ethylhexyl) phthalate  (24%)
Pollutants Detected  in  10%  to  19% of  the NURP Samples

	Inorganics              	Organics	
     None
                              5.  Y-Hexachlorocyclohexane (Lindane) (11%)
                             64.  1,2-trans-Dichloroethene (12%)
                             65.  Trichloroethene  (12%)
                             66.  Tetrachloroethene  (10%)
                             85.  Ethylbenzene  (12%)
                             94.  Pentachlorophenol  (18%)
                             96.  4-Nitrophenol  (10%)
                            103.  Di-n-butyl phthalate  (11%)
                            121.  Phenanthrene  (10%)
a Based on 68 organic and 46 inorganic sample results received as of
  10/31/81, adjusted for preliminary quality control review.  Nine cities
  reporting.  Does not include special metals samples.
                                    17

-------
                                                 TABLE 5.

       SUMMARY OP WATER QUALITY CRITERIA EXCEEDANCES FOR POLLUTANTS  DETECTED IN AT LEAST  10  PERCENT
     OF NURP SAMPLES:   NUMBER OF  INDIVIDUAL SAMPLES  IN WHICH POLLUTANT CONCENTRATIONS EXCEED CRITERIA8

I.


II.









IV.





VI.



VII.


VIII.


Pollutant
PESTICIDES
3. o-Hexachlorocyclohexane
5. Y-Hexachlorocyclohexane (Lindane)
METALS AND INORGANICS
23. Arsenic
26. Cadmiun'3
27. Chromiuirf3'6
28. Copper*3
29. Cyanides
30. Lead1*
32. Nickel"3
33. Selenium
36. Zincd
HALOGENATED ALIPHATICS
51. Methane, trichloro- (chloroform)
58. Ethane, 1,1, 1-trichloro-
64. Ethene, 1 , 2-t rana-d ichloro-
65. Ethene, trichloro-
66. Ethene, tetrachloro-
MONOCYCLIC AROMATICS (EXCLUDING PHENOLS,
78. Benzene
85. Benxene, ethyl-
67. Toluene
PHENOLS AND CRESOLS
94. Phenol, pentachloro-
96. Phenol, 4-nitro-
PHTHALATE ESTERS
103. Phthalate, di-n-butyl
105.. Phthalate, bis(2-ethylhexyl)
Number of times
detected /Number
of samples

16/64
7/64

26/45
17/45
20/44
41/45
10/32
40/43
20/45
9/45
45/45

16/66
23/66
8/66
8/68
7/68
CRESOLS, PHTHALATES)
22/65
8/67
13/55

12/67
7/67

7/61
14/59
Criteria exceedancesb
None FA PC OL HH HCC DW

1,13,16
1 1,2,7

26,26,26
9 17 2 2
1* 1
31 41 -
9
16 40 37 37
8 18
7 7
6 40

8,16,16
X
X
0,1,8
4,7,7

2,22,22
X
X

1* 7« 1
X

6*
13«
IX.    POLYCYCLIC AROMATIC HYDROCARBONS

       121.  Phenanthrene                                 7/67                               7,7,7




 * Indicates PTA or  PTC value  substituted where FA or PC criterion not available (see below).

 * Based on 68 organic and 46  inorganic sample results received as of 10/31/81, adjusted for preliminary
   quality control review.  Nine cities reporting.
FA
PC
FTA
FTC
OL
RH
HC
           Freshwater  ambient  24-hour  instantaneous maximum criterion ('acute* criterion).
           Freshwater  ambient  24-hour average criterion ('chronic* criterion).
           Lowest  reported  freshwater acute toxic concentration.  (Used only when FA is not available.)
           Lowest  reported  freshwater chronic toxic concentration.  (Used only when FC is not available.)
           Taste and odor  (organoleptic) criterion.
           Non'Carclnogenic human health criterion for ingestion of contaminated water and organisms.
           Protection  of human health from carcinogenic effects for ingestion of contaminated water and
          organisms.
  DH   •   Primary drinking water criterion.

c Entries in this column indicate exceedances of the human carcinogen value  at the  10"5,
  10~6, and 10"' risk level, respectively.   The numbers are cumulative,  i.e.,  all 10"'
  exceedances are included in 10"6 exceedances, and all 10~6 exceedances are included  in  10"7
  exeeedances.

d Where hardness dependent, hardness of 100 mg/1 CaC03 equivalent assumed.

4 Different sets of criteria are written for the trivalent and hexavalent forma of  chromium.
  For purposes of this analysis, all chromium is assumed to be in the trivalent form.

                                                   18

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                                                 TABLE 5a.
       SUMMARY OF WATER QUALITY CRITERIA EXCEEDANCES FOR POLLUTANTS DETECTED IN AT LEAST 10 PERCENT
        OF NURP SAMPLES:  PERCENTAGE OF SAMPLES IN WHICH POLLUTANT CONCENTRATIONS EXCEED CRITERIA3
Frequency of
Criteria exceedances U)b
Pollutant detection (») None FA FC OL HH HCC DW
I.


II.









IV.





VI.



VII.


VIII.


PESTICIDES
3. o-Hexachlorocyclohexane
5. Y-Hexachlorocyclohexane (Lindane)
METALS AND INORGANICS
23. Arsenic
26. Cadmium4
27. Chromium3 'e
28. Copper3
29. Cyanides
30. Lead3
32. Nickel3
33. Selenium
36. Zinc3
HALOGENATED ALIPHATICS
51. Methane, trichloro- (chloroform)
58. Ethane, 1,1,1-trichloro-
64. Ethene, 1,2-trana-dichloro-
65. Ethene, trichloro-
66. Ethene, tetrachloro-
MONOCYCLIC AROMATICS (EXCLUDING PHENOLS, CRESOLS,
78. Benzene
85. Benzene, ethyl-
87. Toluene
PHENOLS AND CRESOLS
94. Phenol, pentachloro-
96. Phenol, 4-nitro-
PHTHALATE ESTERS
103. Phthalate, di-n-butyl
105. Phthalate, bie(2-ethylhexyl)

25
11

58
38
45
91
31
93
44
20
100

24
35 X
12 X
12
22
PHTHALATES)
34 X
12 X
24 X

18
10 X

11
24

2,20,25
2 2,3,11

58,58,58
20 38 4 4
2* 2
69 91
28
37 93 86 86
18 40
16 16
13 89

12,24,24


0,1,12
6,22,22

3,34,34



1* 10* 1


10*
22*
 IX.    POLYCYCLIC AROMATIC HYDROCARBONS

        121.  Phenanthrene
                                                           10
                                                                                              10,10,10
 * Indicates PTA or  FTC value  substituted where FA or FC criterion not available (see below).

 • Bated on 68 organic and  46  inorganic sample results received as of 10/31/81, adjusted for  preliminary
   quality  control review.  Nine cities reporting.

 b FA      Freshwater  ambient  24-hour instantaneous maximum criterion ("acute* criterion).
   FC      Freshwater  ambient  24-hour average criterion ("chronic' criterion).
   FTA     Lowest reported  freshwater acute toxic concentration.  (Used only when FA is not available.)
   PTC     Lowest reported  freshwater chronic toxic concentration.  (Used only when FC is  not  available.)
   OL      Taste and odor (organoleptic) criterion.
   HH      Non-carcinogenic human health criterion for ingestion of contaminated water and organisms.
   HC      Protection of human health from carcinogenic effects for ingestion of contaminated  water  and
           organisms.
   DW •    primary drinking water criterion.

c  Entries  in this column indicate exceedances of the human carcinogen value at the 10~5,
   10"6, and 10"' risk level, respectively.   The  numbers  are cumulative,  i.e.,  all  10*5
  •xceedances are included in 10"6 exceedances,  and all  10"6 exceedances are Included in  10~7
  exceedances.

3 Where hardness dependent, hardness of 100 mg/1 CaC03 equivalent assumed.

* Different sets of criteria are written  for the trivalent and hexavalent forms of chromium.
  For purposes of this analysis,  all chromium is  assumed to be in the trivalent form.
                                                 19

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     20 percent of the time.  Freshwater chronic cri-
     teria exceedances were observed for lead,  copper,
     and zinc in at least 89 percent of the samples.
     Drinking water criteria exceedances were signifi-
     cant for lead (86 percent of the time).   For the
     non-carcinogenic human health criterion, lead (86
     percent) and nickel (40 percent)  exceedances were
     most frequent.  Arsenic human carcinogenic crite-
     ria (at all risk levels)  were exceeded 58  percent
     of the time; however,  drinking water standards of
     50 ug/1 for this pollutant were not exceeded.
     (In cases where  inorganic criteria values  are
     water hardness dependent, a value of 100 mg/1
     CaCOo equivalent was assumed.)

5.    Among the organics,  criteria exceedances occurred
     most frequently  in the freshwater chronic  and hu-
     man carcinogenic categories.  Freshwater chronic
     exceedances (utilizing the lowest reported fresh-
     water chronic toxic  concentration)  were  observed
     most often for pentachlorophenol  (10 percent),
     di-n-butyl phthalate (10  percent),  and bis{2-
     ethylhexyl)  phthalate  (22 percent).   Carcinogenic
                                   _5
     criteria exceedances at the 10   risk level
     were observed for o-BHC (2 percent), trichloro-
     methane (12 percent),  tetrachloroethene  (6 per-
     cent),  and benzene (3  percent).   However,  at  the
     10~  risk level  these  exceedances increase to
     25, 24,  22,  and  34 percent,  respectively.   These
     exceedances at the 10~ level  occurred for ev-
     ery sample in which  the pollutant was detected,  a
     result  of the fact that the carcinogenic crite-
     ria levels are less  than  the limits  of detection
     which were used.   For  organics, the  freshwater
     acute and organoleptic criteria were exceeded
     only by  a single pentachlorophenol  sample.

                         20

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    Whenever  a criteria exceedance  is noted above,  this
 does  not  necessarily  imply  that  actual  violations of  cri-
 teria did or  will  take place  in  receiving waters.   Rather,
 the technique used is an  initial screening procedure,  to
 make  a preliminary identification of those pollutants
 whose presence in  urban runoff requires further  study.
 Exceedances of freshwater chronic criteria levels may  not
              **
 persist for a full 24-hour  period,  for  example.  However,
 many  smail urban streams probably carry only slightly  di-
 luted runoff  following storms, and  acute criteria or other
 exceedances may in fact be  real  for such streams.

    While the 65 priority pollutants not detected are  of
 less  immediate concern than those pollutants found often,
 they  cannot safely be eliminated from all future consider-
 ation.  Many  of the pollutants not detected have criteria
 which are  below the detection limits of routine analytical
 methods.  More sensitive analytical methodologies must be
 used  and  dilution  effects considered before it can be said
 with  assurance that these pollutants are not found in ur-
 ban stormwater runoff at levels which pose a threat to hu-
 man health or aquatic life.

    Several non-priority pollutants were reported by the
 laboratory analyzing the Denver runoff  samples (Table 6).
 For example,  the herbicide 2,4-dichlorophenoxyacetic acid
 (2,4-D) was found at a concentration of  180  ug/1, a  level
which violates its drinking  water standard of  100 ug/1.
The Denver results indicate  that  many toxic  compounds
which are not priority pollutants may be found in runoff,
and that such compounds  may  require  further  investigation
and control at some time in  the future.
                             21

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                                TABLE  6.

                NON-PRIORITY  POLLUTANTS REPORTED  IN NURP
                          URBAN  RUNOFF SAMPLES
                 Pollutant
Estimated   Number of times
concentra-  detected/Number
tion ( uj/1)    of samples
 6-Methoxy-N,N'-bis(l-methylethyl)-l,3,5-
  triazine-2,4-dione                         64               1/7
 4-Propoxyphenol                              8                1/7
 Methylheptanol                               12               1/7
 3-Methyl-2-cyclohexen-l-one                  6-9              4/7
 l-(2-Butoxyethoxy)ethanol                    5-23             2/7
 2,2,4-Trimethyl-l,3-pentanediol              17               1/7
 Tributylphosphate                            6                1/7
 9,10-Anthracenedione or
  9,10-Phenanthrenedione                     20-29            2/7
 2,4-Dichlorophenoxyacetic acid or 2,4-D      180              1/7
 (l,l'-biphenyl)-carboxaldehyde               17               1/7
 Unidentified substituted alkyl hydrocarbon   5-37             3/7
 Unidentified substituted alkyl hydrocarbon   12-390           2/7
Unidentified substituted alkyl
  hydrocarbon oil                            10-500           2/7
Unidentified substituted polycyclic
  aromatic                                   22               1/7
2,/2-(2-Butoxyethoxy)ethoxy/ethanol  '8               .  1/7
Note:  Results reported by the Denver  NURP program.
                                   22

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                         SECTION 4

                        CONCLUSIONS
    Section 3 identified the  inorganic  and  organic  prior-
ity pollutants which were most frequently detected  in  ur-
ban runoff and which were found at undiluted  concentra-
tions exceeding applicable water quality criteria and
          *
standards.  The 24 pollutants  (9 inorganics and  15  organ-
ics) detected in greater than  10 percent of the  urban  run-
off samples have been selected for further  evaluation  and
discussion in this section.  A cutoff point of 10 percent
was used because the data are preliminary and the cutoff
tends.to minimize unusual runoff conditions.  More  pollu-
tants will be analyzed in future reports.

    The 24 priority pollutants found in 10  percent  or  more
of the NURP samples, and their predominant  sources,  are
shown in Table 7.  In general, priority pollutant inor-
ganics were found more frequently and at higher  concentra-
tions than the priority pollutant organics.   The inorgan-
ics found most frequently and  at the highest  concentra-
tions were arsenic, cadmium, chromium,  copper, cyanide,
lead, nickel, and zinc.  Predominant sources  of  these
metals in runoff are thought to be fossil fuel and  gaso-
line consumption, metal alloy corrosion, and  automobile
tire wear.  Lindane ( r-BHC) ,  o-BHC, chloroform,  1,1,1-
*A11 findings and conclusions are considered tentative, until  corpletion.
 of thorough quality assurance review.
                              23

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                               TABLE 7.

      PREDOMINANT SOURCES OF PRIORITY POLLUTANTS WHICH HAVE BEEN
       DETECTED  IN AT  LEAST 10  PERCENT OF URBAN RUNOFF SAMPLES
           Pollutant
     Predominant sources
121.  Phenanthrene
 23.  Arsenic
 32.  Nickel
 30.  Lead
 78.  Benzene
 85.  Ethylbenzene
 87.  Toluene
 96.  4-Nitrophenol

 29.  Cyanide
 26.  Cadmium
 27.  Chromium
 28.  Copper
 29.  Cyanide


 36.  Zinc



 51.  Chloroform



(continued)
Fossil Fuels Combustion

Product of the incomplete com-
bustion of fossil fuels, espe-
cially wood and coal burned in
residential home heating units.

Products of fossil fuel
combustion.

Gasoline Consumption

Components of gasoline
Product of gasoline combustion

Metal Alloy Corrosion

Metals released from the corro-
sion of alloys and from elec-
troplating wastes.

Metal released from the corro-
sion of copper plumbing and
from electroplating wastes.
Copper is also commonly used
in algicides.

Automobile Related Activities

Anti-caking ingredient in  road
salts.

Component of automobile tires
and a common ingredient in
road salt.

Product of a chemical
interaction among road salt,
gasoline, and asphalt.
                                24

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TABLE 7.  (Continued)
           Pollutant
                                       Predominant Sources
  3.   o-BHC
  5.   rBHC (Lindane)
 94.  Pentachlorophenol
 58.
 64.
 65.
 66.
1,1,1-Trichloroethane
1,2-trans-Dichloroethene
Tr ichloroethene
Tetrachloroethene
103.
105.
Di-n-butyl phthalate
Bis(2-ethylhexyl) phthalate
e.   Pesticide Use

     Compounds commonly used in soil
     treatment to eliminate nema-
     todes and other pests.

     Primarily used to protect wood
     products from microbial and
     fungal decay.  Telephone poles
     are commonly treated with pen-
     tachlorophenol, for example.

f.   Solvent Use by Light Industry

     Products used in solvents by
     light industries (e.g., dry
     cleaning, auto repair, paint
     contractors, metal finishing
     and degreasing) to dissolve
     grease and clean parts.  The
     "spent" solvent typically
     finds its way into drains,
     open storm drains,  and surface
     runoff due to careless dis-
     posal practices.

g.   Plastic Product Consumption

     Two of the most widely used
     plasticizers (components which
     make plastic flexible).  They
     find their way into urban run-
     off because, through .time,
     they "leach" from numerous
     plastic products (e.g., garden
     hose, floor tile, plastic con-
     tainers, food packaging)  in
     which they are found.

h.   Natural Erosion
 33.  Selenium
                                  Element which occurs naturally
                                  in rocks and soil.
                                   i.    Chlorination of  Drinking  Water
                                        and  Municipal Wastewater
 51.   Chloroform
                                  Chemical compound formed as a
                                  result of the Chlorination of
                                  drinking water and wastewater.
                               25

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trichloroethane, benzene, toluene,  bis(2-ethylhexyl)
phthalate, phenanthrene,  and pentachlorophenol were the
priority pollutant organics found most frequently and at
highest concentrations.  Their predominant sources are
believed to be pesticides, solvents, plastic products, and
water chlorination practices.

POTENTIAL RISK TO HUMAN HEALTH

    A comparison of undiluted NURP priority pollutant con-
centrations with EPA's human health criteria for water
revealed that the organic priority pollutants found most
frequently pose little risk to humans at detected levels,
except possibly for phenanthrene and chloroform.  Ten per-
cent of the urban runoff samples for these two pollutants
contained concentrations greater than the EPA criteria for
protection of health from carcinogenesis at a 10   risk
level.  Pentachlorophenol (PCP)  exceeded the organoleptic
criterion in one sample,  although it was found in 18  per-
cent of the samples.  PCP does not appear to be a carcino-
gen, but tests with rats have shown it to be teratogenic
and fetotoxic.

    Additional dilution during storm events may reduce the
concentrations of the organic pollutants found from the
levels measured in runoff.  This, in addition to known
fates and pathways of these organic pollutants, suggests a
minimal risk to humans due to urban runoff-borne priority
pollutants.  Chloroform,  solvents,  and gasoline-related
organics found in urban runoff are rather volatile (half-
life 30 minutes) and are  not expected to persist in sur-
face waters.  These compounds can be expected to persist
in groundwater, however,  where they are not able to vola-
tilize.
                            26

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    PCP has a short lifetime in water  because photolysis
degrades it in streams within approximately one week.
However, where conditions such as turbidity limit photo-
lysis, degradation may take as long as several months.
PCP also sorbs to sediments where it can persist for
months and eventually recontaminate the water column,
which can be a problem in streams that are attempting  to
recover from intermittent or continuous discharges.
Phenanthrene is also readily adsorbed to sediments where
it can persist and recontaminate the water column.  The
effect of remobilization of these pollutants from sedi-
ments must be further evaluated before a conclusion
regarding potential risk to human health can be fully
stated.  If PCP and phenanthrene are found in additional
NURP samples at concentrations of concern, monitoring  may
be recommended at nearby water supplies.

    The predominant pathway for human exposure for the
organics associated with gasoline is through ingested  food
and inhalation.  Contaminated surface water should there-
fore pose little risk at the levels measured in NUPNP sam-
ples.  The plasticizers and pesticides should also pose a
minimal threat to humans as contaminated surface water is
an insignificant exposure pathway for these chemicals.
The plasticizer values in urban runoff are orders of mag-
nitude below toxic levels.  However, bis(2-ethylhexyl)
phthalate has been shown to accumulate in aquatic life and
sediments.  The effects of exposure to humans due to these
pathways at measured concentrations are currently unknown.

    Some of the priority pollutant metals found in urban
runoff could represent a potential risk to human health.
Exceedances of the non-carcinogenic human health, drinking
water, and human carcinogenic criteria were observed.
Detected lead concentrations in undiluted runoff ranged
                             27

-------
from 38 to 445 ug/1 and exceeded the drinking water stan-
dard and human health criterion of 50 ug/1  (total lead)  in
86 percent of the samples.  Selenium concentrations in
undiluted runoff of from  2 to 25 ug/1 exceeded the drink-
ing water standard and human health criterion of 10 ug/1
(total .selenium) in 16 percent of the samples.  Although
dilution in receiving streams and subsequent treatment in
drinking water treatment  facilities would likely reduce
these observed concentrations, drinking water standard
violations are still possible under worst case condi-
tions.  Such conditions would include cases where:
(1) the runoff generated  during a storm event represented
a large portion of the total receiving water flow, result-
ing in a dilution of less than 1 to 10; (2) the prelimi-
nary sampling results are representative of lead and
selenium concentrations above drinking water supply in-
takes; and (3) lead and selenium removal by public drink-
ing water treatment facilities is minimal.  Specific risks
to drinking water supplies could be evaluated by confirma-
tory sampling during storm events.

    Nickel concentrations in undiluted runoff were found
to exceed the human health criterion of 13.4 ug/1 (total
nickel) in 40 percent of  the samples with detected total
nickel concentrations ranging from 5 to 270 ug/1.  Viola-
tions are expected to be  less than the 40 percent figure
after dilution by receiving streams.  Moreover, nickel is
not considered a significant human health problem in water
because it is poorly absorbed by the body when ingested.
Inhalation of nickel,  especially nickel carbonyl, poses
the greatest risk to human health.  However, nickel com-
pounds are suspected of acting synergistically with some
carcinogens to increase mutagenic effects (Sunderman,
1981).
                             28

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    Arsenic concentrations in undiluted runoff frequently
                                                _ c
exceeded the EPA human carcinogenic criteria (10   risk
level) of .022 ug/1.  There is, however, presently a de-
bate on the carcinogenic potency of arsenic, and this pre-
cludes a meaningful assessment of the risk to humans at
this time.  The arsenic levels in the undiluted runoff
were all below the 50 ug/1 EPA drinking water standard.

POTENTIAL RISK TO AQUATIC LIFE

    Only one organic priority pollutant, pentachloro-
phenol, was found to exceed freshwater acute aquatic life
criteria.  This occurred only once, although the compound
was detected in 12 out of 67 NURP samples.

    Four priority pollutant metals, cadmium, copper, lead,
and zinc, exceeded acute criteria in 13 to 68 percent of
the samples.  The highest detected values for these pollu-
tants were two to five times higher than their appropriate
criteria.  Consequently, these pollutants could cause harm
to aquatic life, depending upon receiving stream dilution.

    These same four priority pollutant metals, plus nickel
and cyanide, also exceeded 24-hour freshwater chronic cri-
teria in 18 to 93 percent of the samples.  The highest
detected values for these pollutants ranged from 3 to 680
times higher than their appropriate criteria.  However,
attenuating circumstances such as dilution and storm dura-
tion must be taken into account in order to fully evaluate
the significance of these exceedances.  Since most storms
last between 2 and 16 hours, violations of chronic cri-
teria levels appear to be unlikely.  The long-term effects
on aquatic life of these pollutants bound to sediments,
however, are unknown.  These six pollutants may accumu-
late to some degree in sediments.
                             29

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    One final observation can be made regarding toxic
metal problems in runoff and receiving stream waters.
Many metals appear to be bound to organic matter or min-
eral particulates in water or bottom sediments.  Through
desorbtion they are potentially available for movement in
a soluble form into the water column.  In many cases de-
sorbtion is governed by the physical-chemical parameters
of pH, oxidation-reduction potential (EH), and dissolved
oxygen (DO).  Low (acid) pH, EH, and DO favor solubility.
Current research on acid precipitation suggests that the
pH and possibly the EH of stormwater in many locations is
decreasing.  Consequently, an increase in the concentra-
tion of soluble metals and therefore the toxicity of these
pollutants in the water might be expected.
                             30

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                          SECTION 5

               SPECIAL METALS SAMPLING PROJECT
INTRODUCTION
     The Special Metals Project was initiated to enhance
the usefulness of the NURP priority pollutant metals data
base and to provide additional perspective on the potential
toxicity of priority pollutant metals in urban runoff.  The
primary objective of this project was to determine the re-
lationship among dissolved, total, and total recoverable
concentrations of 29 metals (Table 8), including both prior-
ity and non-priority pollutant metals, and to evaluate the
potential impact of priority pollutant metals in urban run-
off on aquatic life and water supplies.  A secondary ob-
jective was to ensure a high level of quality in the
generated data by having all the metal analysis conducted at
a single laboratory.  This project, therefore, expands the
NURP priority pollutant metals data base which provides re-
sults for only one form (or fraction) of each metal's con-
centration, and which uses numerous laboratories.
     Definitions of the three metal fractions analyzed in
this project are given below:
          •  Dissolved metals - those constituents (metals)
             which will pass through a 0.45 micron membrane
             filter.  Occasionally referred to as "soluble"
             metal content.
          •  Total recoverable metals - the concentration of
             metals in an unfiltered sample following treat-
             ment with hot dilute mineral acid. Occasionally
             referred to as "extractable" metal content.
          •  Total metals - the concentration of metals
             determined in an unfiltered sample following
             vigorous digestion with concentrated nitric
             acid.
                             31

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                               Table 8
               Special  Metals Project:   Parameter List
Priority Pollutant Metals

     Arsenic (As)
     BeryI I I urn (Be)
     Cadmium (Cd)
     Chromium (Cr)
     Copper  (Cu)
     Lead (Pb)
     Mercury (Hg)
     Nickel  (Nl)
     Selenium (Se)
     SI Iver  (Ag)
     Thai Ilum (T|)
     Zinc (Zn)
Non-Priority Pollutant Metals
        Aluminum (A I )
        Barium (Ba)
        Boron (B)
        CaIcI urn (Ca )
        Cobalt-(Co)
        Iron (Fe)
        Lithi urn (Li )
        MagnesI urn (Mg)
        Manganese (Mn)
        Molybdenum  (Mo)
        Potass I urn (K)
        Sodium (Na)
        StrontI urn (Sr )
        Tin (Sn)
        Titanium (Tl)
        Vanadium (V)
        Yttrium (Y)
                                32

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     The three forms of metal are identified and quantified
because:  (1) in most cases, aquatic life toxicity is be-
lieved to be directly related to the amount of dissolved
metal available, and (2) total recoverable and total metals
results are directly comparable to EPA water quality
criteria and drinking water standards, respectively (Ap-
pendix D).  Although the dissolved metal fraction is most
directly related to toxicity, criteria and standards are
based on total metals fractions because they provide an
indication of the amount of metal available for dissolution.
EPA's 1980 water quality criteria for priority pollutant
metals are based on laboratory toxicity tests in which the
actual form of the metal as measured in concentration may
not be known with certainty;  most of these tests were pro-
bably conducted using metals in the more toxic, dissolved
form.  The criteria for metals, however, are expressed in
terms of total recoverable metal in an effort to provide
adequate protection of aquatic life.  This fraction was
selected as the basis for the criteria because:  (1) the
actual form of the metal reported in laboratory toxicity
tests may not be known, and  (?.) metals in the aquatic en-
vironment may undergo reactions which convert various forms
of the metal into the dissolved fraction.  EPA's drinking
water standards, however, are based on the total metals
fraction.  Consequently, to  identify potential effects of
urban runoff on aquatic life and on water supplies, a com-
parison of both total recoverable and total metal con-
centrations against respective criteria and standards is
needed.
     As part of this project, 17 non-priority pollutant
metals were also measured in the three fractions since the
analytical procedures provide this information at no ad-
ditional cost.  These data are available to all NURP cities
and may be analyzed for potential water quality impacts in
future EPA NURP assessments.  The concentrations of three of
                             33

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these metals (Ca, Mg, and Sr) were used to calculate hard-
ness for each sample.  These hardness values were then used
to calculate the applicable EPA water quality criteria for
selected priority pollutant metals with hardness-dependent
criteria.
METHODOLOGY
     Twenty-five NURP cities (Table 9 and Figure 2) are
participating in this project.  These cities have been
supplied sampling kits with sufficient supplies to collect
eight runoff samples for each of the three fractions.  Con-
sequently, a maximum of 200 samples can be analyzed for each
of the three fractions.  Along with the sampling kit, a
sampling manual  and recommendations on sampling were
provided.  These recommendations are as follows:
  l..The samples collected should be either flow-composited
     or a series of discrete samples for a runoff event.
  2. The special metals sample may be split out of the sam-
     ple collected for priority pollutant analysis, or
     for those cities not participating in the toxic sam-
     pling program, the sample may be split out of a sam-
     ple collected for conventional pollutant analysis.
     The analytical methods  followed by the contracted
laboratory are in accordance with the EPA approved pro-
cedures published in Methods for Chemical Analysis of Water
and Wastes (USEPA, 1979), and Inductively Coupled Plasma  -
Atomic Emission Spectrometric Method for Trace Element An-
alysis of Water and Wastes  (USEPA, 1980).  Table 10
summarizes the analysis procedures used and references the
EPA methods and detection limits for each metal.  The use of
the Inductively Coupled Plasma-Atomic Emission Spectrometric
Method (ICP) for trace element analysis of runoff samples
provides a multi-element analysis at no additional cost.
                              34

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                                  Table 9
      NURP  Cities  Participating  In  the Special  Metals Sampling Project
                                 Durham,  NH*
                           Lake QuInsigamond,  MA*
                             Mystic  River,  MA»
                            Irondequoit Bay, NY*
                              Lake George,  NY*
                              Long Island,  NY*
                               Baltimore, MD*
                              Wash I ngton, DC*
                               KnoxviIle, TN»
                                 Tampa, FL*
                             Wlnston-SaI em, NC
                            Champa Ign-Urbana,  IL
                               Ml Iwaukee, WI
                               Chicago,  IL*
                               Trl-County,  Ml
                               Washtenaw, Ml
                                Austin, TX*
                              Little Rock,  AR*
                              Kansas City,  MO*
                                Denver, CO*
                              Rapid  City, SD*
                            Salt Lake City, UT*
                                 Fresno,  CA
                               Be I levue,  WA*
                                Eugene, OR*
*Also participating in the NURP priority pollutant sampling program.
                                  35

-------
CO
er>
                                                                                       o so no  Mo  100
                                                                                                  m
                                                                                                  MILES
    Numbers Identify major river basins
    delineated by (he United Stales
    Geological Survey,  1980.
     •: Priority Pollutant City
     O r Non Priority Pollutant City
                                Figure  2   NURP  Special Metals City Locations

-------
                                 Table  10
                Summary  of  Analytical  Procedures  Used  in  the
                      Special  Metals  Sampling  Program
Metal
Arsen 1 c { As )
Bery Ilium (Be)
Cadml urn (Cd)
Chroml urn (Cr )
Copper (Cu)
Lead (Pb)
Mercury ( Hg )
NI ckel (Nl )
Selenium (Se)
SI 1 ver (Ag)
Thai 1 lum (Tl )
Zinc (Zn)
Aluminum (Al)
Bar 1 urn (Ba )
Boron (B)
Calcium (Ca)

(Cobalt (Co)
Iron (Fe)
Lithium (LI)
Magnes I urn (Mg )
Manganese (Mn )
JMo 1 ybdenum (Mo)
Potassium (K)
Sodium (Na)
Strontium (Sr)
Tin (Sn)
Titanium (Ti)
Vanadium (V)
Yttrium (Y)
Method Ana 1 y s 1 s
Furnace AA ( 1 )
ICP (3)
ICP (3)
ICP (3)
ICP (3)
ICP (3)
Cold Vapor AA (5)
ICP (3)
Furnace AA ( 2 )
ICP (3)
Furnace AA (2)
ICP (3)
ICP (3)
ICP (3)
ICP (3)
ICP (3)

ICP (3)
ICP (3)
ICP (3)
ICP (3)
ICP (3)
ICP (3)
ICP (3)
ICP (3)
ICP (3)
ICP (3)
• ICP (3)
ICP (3)
ICP (3)
Reference No.
206.2 (2)
200.7 (4)
200.7 (4)
200.7 (4)
200.7 (4)
200.7 (4)
245.1 (2)
200.7 (4)
270.2 (2)
200.7 (4)
279.2 (2)
200.7 (4)
200.7 (4)
200.7 (4)
200.7 (4)
Detect Ion Limit
ua/l
10
2
5
10
20
40
1
20
10
10
10
10
50
10
10
200.7 (4) ! 100
i
200.7 (4) 10
200.7 (4) j 20
200.7 (4)
200.7 (4)
200.7 (4)
200.7 (4)
200.7 (4)
200.7 (4)
200.7 (4)
200.7 (4)
200.7 (4)
200.7 (4)
200.7 (4)
10
100
10
10
200
100
10
50
10
10
10
Footnotes:

'Atomic Absorption, Furnace Technique.

^U.S. Environmental Protection Agency.  1979.  Methods for the Chemical
Analysis of Water and Wastes.  Environmental  Monitoring and Support
Laboratory.  Office of Research and Development.  Cincinnati, Ohio.

'inductively Coupled Plasma-Atomic Emission SpectrometrIc Method.

^U.S. Environmental Protection Agency.  I960.   Inductively Coupled
Plasma-Atomic Emission SpectrometrIc Method for Trace Element Analysis cf
Water and Wastes.  Environmental  Monitoring and Support Laboratory.
Office of Research and Development.   Cincinnati, Ohio.

^Manual Cold Vapor Atomic Absorption Technique.

                                    37

-------
Therefore, besides data on the priority pollutant metals,

which are of primary concern, data on 17 additional metal

elements are provided.

     Four data analysis approaches are used to summarize

preliminary results:

  1. Metals are identified by frequency of detection,
     including calculations of geometric mean con-
     centrations of each fraction (total, total re-
     coverable, and dissolved).

  2. Comparisons are made of priority pollutant metals
     concentrations (total recoverable and total metal) of
     undiluted urban runoff  with EPA's water quality
     criteria and drinking water standards, respectively.
     These comparisons identify exceeded criteria and
     standards in an effort to evaluate the potential
     downstream effects oh aquatic life as well as the
     potential impacts on water supplies.

     EPA water quality criteria for the protection of
     aquatic life are of two types:  (1) "acute" represent
     the maximum concentration of a pollutant at any time;
     (2) "chronic" represents the maximum 24-hour average
     concentration allowed.

     Those criteria that are hardness dependent were
     adjusted using the hardness values calculated for each
     water sample using Ca, Mg and. Sr concentrations.
     (Hardness values ranged from 11.2 to 452 with the
     arithmetic mean being 113 mg/1.) .

  3. Comparisons are made of dissolved metals
     concentrations with total and total recoverable
     concentrations to identify the relative importance of
     each fraction for each metal.

  4. Comparisons are made of special metal concentrations
     with results of metals analyzed in the NURP priority
     pollutant monitoring effort when samples were sampled
     simultaneously for both programs.

  5. Comparisons are made of non-priority pollutant metal
     concentrations (total metal) found in undiluted urban
     runoff with EPA's "Red Book" Criteria.
                              38

-------
     At this time, the focus of the data analysis is on the
priority pollutant metals.  A range of the geometric mean
was calculated for each parameter, based on assumptions made
in the EPA-Water Planning Division report "Preliminary
Results of the NURP Program."   Since it is not appropriate
to calculate a mean if most of the values are undetected,
only metals found in at least 10 percent of the samples are
included in this analysis. Two geometric means were computed
to identify a range within which the actual mean falls. The
upper end of the range was calculated using the actual de-
tection limit when the pollutant was undetected.  The lower
end was calculated using a very small number  (0.1 times the
detection limit) for the undetectable (remarked) result in
order to avoid zero, which cannot be accommodated in
geometric mean calculations. Mean concentrations were also
only calculated on composite samples; therefore, the total
sample size was 46.  The 14 discrete samples were excluded
because they do not provide an adequate representation of
the runoff event concentration.
     The data analysis used event mean concentration which
is calculated by dividing the mass discharge, whether it be
total, total recoverable, or dissolved, by the total runoff
volume.  If a flow-weighted composite was collected, the
metal concentration was used to represent the event mean
concentration.  No flow data were reported for discrete
samples and, consequently, event mean concentrations could
not be calculated.  These discrete samples did provide data
on the instantaneous metal content of various periods in a
runoff event and were used in determining the percent of
total metal in the various metal fractions.
                             39

-------
FINDINGS
     Raw sampling data for all pollutants are given in Ap-
pendix E and summarized in Table 11.  Appendix F contains
preliminary laboratory quality control (QC) data.  In
general this QC data meets established laboratory control
limits (except for aluminum, boron, and iron ), including
control limits specified in "Quality Assurance for Labora-
tory Analysis of 129 Priority Pollutants" (U.S. Environ-
mental Protection Agency, Monitoring and Data Support
Division, February 4, 1980).  Recoveries for spiked samples,
method standards, and reference standards are within 90 to
110 percent for most metals, and replicate standard de-
viations. (RSD's) for duplicate samples are generally less
than 10 percent.
     Specific results and findings are summarized below:
  1. Eight priority pollutant metals were detected in the
     total fraction. Their frequency of detection and range
     of values are shown below.  The range surrounding the
     geometric mean is also provided for the metals found
     in at least 10% of the samoles.
             Frequency         Range of        Range of
            Found Above     Detected Values Geometric Mean*
        Detection Limit  (%)      (ug/1)	(ug/1)
Zinc
Lead
Copper
Chromium
Nickel
Cadmium
Beryllium
Arsenic
92
70
53
45
27
8
8
3
10-730
40-740
20-120
10-80
20-60
5
2
10-20
103-133
43-106
7-27
4-14
4-21
-
:
*Based on "total metal" values calculated in Appendix E and
presented in Table 11.
                             40

-------
                                                               Table II
                         Summary of Number of Detections, Mean Concentrations, Range and Detection Limits for
                                           Special  Metals Data Collected as of October 1961
                                    (Composite Samples Only - 46 Samples: concentrations In ug/l)
Pollutant Form
Total
Arsenic Total Recoverable
Dissolved
Total
Beryllium Total Recoverable
Dissolved
Total
Cadmium Total Recoverable
Dissolved
Total
Chromium Total Recoverable
Dissolved
Total
Copper Total Recoverable
Dissolved
Total
Lead Total Recoverable
Dissolved
Total
)«ercury Total Recoverable
Dissolved
Total
Nickel** Total Recoverable
Dissolved
Total
Selenium Total Recoverable
Dissolved

Total
Silver Total Recoverable
Dissolved
Number of
Detected Values
1
0
0
4
0
t
4
t
2
20
13
0
20
21
4
28
28
0
0
0
1
12
4
1
0
0
0

0
0
0
Geometric Mean
RMK m 0. 10 RMK*
—
-
-
_
-
-
„
.
-
4
2
-
7
8
•
43
42
-
.
-
-
4
-
-
.
-
-
"I
'-
-
—
Geometric Mean
RMK • RMK*
—
-
-
.
-
-
.
.
-
14
12
-
27
27
-
106
103
-
_
-
-
21 -
-
-
_
-
-

-
-
•
Range of
Detected Values
20
-
-
2
-
2
5
3
t - 10
10 - 80
10 - 80
-
20-120
20-110
20-80
40 - 740
40 - 740
-
.
-
1
20 - 60
20 - 40
140
„
-
-

-
-
—
Detection
Limit
10
10
10
2
2
2
3
3
•5
10
10
10
20
20
20
40
40
40
1
1
1
20
20
20
">
10
10

10
10
10
 *RMK  • REMARK and  Indicates non-detection.

••ContamI nation  suspected In dissolved fraction.
                                                           41

-------
                                                           Table  11  (Cont.)
                         Summary  of  Number of  Defections, Mean Concentrations, Range  and  Detection  Limits  for
                                          Special Metals Data Collected  as of October  1981
                                    (Composite Samples Only - 46  Samples: concentrations  In  ug/l)
Pollutant Form
Total
Thallium Total Recoverable
Dissolved
Total
line Total Recoverable
Dissolved
Total
Aluminum Total Recoverable
Dissolved
Total
Barium Total Recoverable
Dissolved
1 Total
Boron" Total Recoverable
' • DI sso I ved
Total
, Calcium Total Recoverable
Dissolved
' Total
! Cobalt Total Recoverable
j . Dissolved
i Total
Iron Total Recoverable
Dissolved
Total
lltllum Total Recoverable
Dissolved
Total
Magnesium Total Recoverable
Dissolved
Number of
Detected Values
0
0
0
41
43
37
43
46
12
43
42
38
32
43
38
46
46
46
2
4 '
0
46
46
37
11
to
9
46
46
46
Geometric Mean
RMK • 0.10 RMK*
^
-
-
103
tie
28
2,303
1,487
11
43
34
28
13
27
22
20,220
19,289
13,925
.
-
•
3,531
2.668
31
2
2
2
5.339
5,200
2,745
Geometric Mean
RMK • RMK*
—
-
-
133
137
43
2,423
1,487
58
50
41
42
27
32
33
20,220
19,289
13.925
.
-
-
3,531
2.668
49
14
13
12
3,339
5,200
2,745
Range of
Detected Values
^
-
-
10 - 730
20 - 690
10 - 550
200 - 74,400.
50 - 44,900
50 - 500
10 - 600
10 - 570
10 - 190
10 - 180
10 - 160
10 - 230
3,100 - 121,000
3,000 - 121,000
2,300 - 133,000
20-30
10 - 20
-
300 - 69,900
280 - 48.600
20 - 470
!0 - 1,140
10 - 1,200
10 - 1,300
900 - 26.800
900 - 25,100
300 - 28,500
Detection
Limit
10
10
10
to
10
10
50
SO
50
to
to
to
10
to
10
too
too
too
to
10
10
20
20
20
10
10
10
too
100
too
•RMK • REMARK and Indicates non-detection.
••Contamination suspected In dissolved  fraction.
                                                           42

-------
                                                                 Table II (Cont.)
                               Summary of Number of Detections,  Mean Concentrations, Range and Detection Limits for
                                                 Special  Metals  Data Collected as of October 1981
                                          (Composite Samples Only - 46 Samples: concentrations In ug/l)
Pol lutant

Manganese


Molybdenum


Potassium


Sodium


Strontium


Tin


Titanium


vanadium


Yttrium

Form
Total
Total Recoverable
Dissolved
Total
Total Recoverable
Dissolved
Total
Total Recoverable
Dissolved
Total
Total Recoverable
Dissolved
Total
Total Recoverable
Dissolved
Total
Total Recoverable
Dissolved
Total
Total Recoverable
Dissolved
Total
Total Recoverable
Dissolved
Total
Total Recoverable
Dissolved
Nunber of
Detected Values
45
45
30
4
0
1
46
46
46
46
46
46
46
46
46
3
0
0
36
40
1
14
13
0
3
5
0
Geometric Mean
RMK « 0. 1 0 RMK*
124
124
11
.
-
-
2,941
2.823
3.130
5,992
6,158
6,913
86
86
66
_
-
-
36
39
-
3
2
-
_
1
~
3oometric Mean
SMK o RMK*
130
130
25
.
-
-
2,941
2,825
3.130
5,992
6,158
6,913
86
86
66
.
-
-
59
53
-
13
12
-
_
It
—
Detected
10 -
10 -
10 -
10 -
-
10
700 -
400 -
800 -
700 -
900 -
900 -
20 -
20 -
10 -
30
-
-
20 -
10 -
20
10 -
10 -
-
20 -
10 -
•
Values
1,620
1,550
290
20


16.900
14.600
6,300
142,000
148,000
160,000
4,490
4,290
5.200



2.490
890

160
90

40
40

- - ,» • '
Limit
10
10
10
10
10
10
200
200
200
100
100
100
10
10
10
SO
50
SO
to
10
10
10
10
10
10
10
10
•RMK • REMARK and Indicates non-detection.

-------
  2. Comparisons of total recoverable and total metal
     concentrations (undiluted by stream flow) with EPA
     water quality criteria and drinking water standards,
     respectively, reveal that lead, copper, and zinc
     exceed acute criteria in greater than 37 percent of
     the samples while they exceed chronic criteria in
     greater than 53 percent of the samples (Table 12).
     Lead concentrations were found to exceed EPA's
     drinking water standards in 63 percent of the
     samples.

  3. A comparison of the priority pollutant metal fractions
     (Table 13a)  revealed that, in general, most of the
     metals are in the particulate form; most of the metals
     associated with particulates are in the total
     recoverable fraction.  However, copper, and zinc both
     are present at 27 percent in the dissolved form.  For
     non- priority metals (Table 13b), a larger percent of
     the metal concentration is in the dissolved fraction.
     More than 90 percent of potassium,  sodium, lithium,
     and boron are present in the dissolved fraction, as
     expected due to the high solubility of these metal
     salts.

  4. Four of the non-priority metals  (barium, boron, iron
     and manganese) have criteria available in EPA's "Red
     Book" (Table 14).  In undiluted runoff, barium and
     boron did not exceed criteria; iron and manganese
     exceeded the criteria for domestic water supplies
     (welfare) in 98% and 77% of the respective samples.
     These criteria are established to prevent brownish
     staining of laundry and plumbing fixtures and
     objectional taste in beverages.

CONCLUSIONS

     For this preliminary screening analysis, the results
indicate that zinc, lead, copper and chromium are the metals

found most frequently and at the highest concentration.

     Lead concentrations in undiluted runoff were found to
exceed the drinking water standard and human health
criterion of 50 ug/1 (total lead) in 63 percent of the

samples, with detected total lead concentrations ranging
                             44

-------
                                                                             Table  12
                                                          Summary of Water Quality Criteria Violations
                                                          (Analyses of data  uses detected  values only)
Metal i of Samples
Arsenic
Beryl Hum
Cadmium
Chromium
Copper
Lead
Mercury
Nickel
Selenium
S 1 1 ver
Thai Hum
Zinc
60
60
60
60
60
60
60
60
60
60
60
60
Percentage of Samples In Violation
Freshwater
Acute
0
0
3C
0
42b'C
43b
0
0
0
oc
0
37 b
Freshwater
Chronic
0
0
3C
2
53b'C
68b'C
0
0
0
oc
0
85 b
Human
Health
oc
0C
2
2
NCA
63b
0C
)2c
0
0
0
NCA
Drinking Water
Standard
0
NS
2
2
0
63b
0
NS
0
0
0
0
Ln
      Footnotes:

      aVlolatlons based on total recoverable fraction only.

      "Five violations as a result of 5 discrete samples collected for a single runoff event In Long  Island, NY., May  II,  1981.

      cDetectlon  limit Is higher than criteria for the metal; therefore, the violation Incidence could be higher than  shown.

-------
                                 Table  13a
            Total Recoverable and Dissolved Metals Concentration
                as a Percent of Total Metals Concentration:
                         Priority Pollutant Metals
                           (Based on 60 samples)

2 3
Arsenic RMK = 0
RMK = RMK
2
Bery 1 1 i urn RMK = 0
RMK = RMK
2
jCadm i urn RMK •= 0
RMK = RMK
Chromium RMK = 0
RMK » RMK
Copper RMK = 0
RMK = RMK
Lead RMK = 0
RMK = RMK
2
Mercury RMK = 0
RMK = RMK
Nickel RMK » 0
RMK = RMK
2 .
Selenium RMK = 0
RMK » RMK
SI 1 ver 2 RMK = 0
RMK * RMK
2
Tha 1 1 1 urn RMK = 0
RMK = RMK
21 nc RMK = 0
RMK = RMK
Percent Tota 1
Recoverab 1 e
.
-
_
-
—
-
61
77
93
94
94
95
_
-
35
85
—
-
_
-
—
-
64
65
Percent
D i sso 1 ved
.
.
_
-
—
-
0
41
27
53
4
18
_
-
_
-
_
-
_
-
—
-
27
28
Frequency of Detection
In Total Fraction (?)
2

7

7

33

33

47

0

20

0

0

o- '

68

^Determined using only those samples with a detectable  level of metal  in
the total fraction for greater than  10$ of the samples  analyzed.
       than IOJ of the samples had detectable levels of metal  In the
total fraction.
     = 0:   Percentages have been calculated substituting zero for  less
            than detectable values in the dissolved and total recoverable
            f ract I ons.
 RMK = RMK: Percentages have been calculated substituting the detectable
            limit for less than detectable values in the dissolved and
            total recoverable fractions.

 One data point eliminated from data set due to field contamination.

                                  46

-------
                     Table  13b
Total  Recoverable and Dissolved Metals  Concentration
    as a Percent of Total  Metals Concentration:
           Non-Priority Pollutant Metals
               (Based on 60 samples)

Aluminum
Barium
Boron
Calcium
Coba It2
1 r on
L i th I urn
Magnes i urn
Manganese
f
Mo 1 y bdenum*
Potass i urn
Sod i urn

RMK3* 0
RMK n RMK
RMK = 0
RMK = RMK
RMK = 0
RMK B RMK
RMK = 0
RMK » RMK
RMK B 0
RMK *> RMK
RMK = 0
RMK ° RMK
RMK » 0
RMK •= RMK
RMK = 0
RMK = RMK
RMK = 0
RMK = RMK
RMK « 0
RMK o RMK
RMK 3 0
RMK * RMK
RMK - 0
RMK B RMK
Percent Total
Recovera b 1 e
64
64
85
86
100+
100+
95
95
-
75
75
97
99
97
97
97
97
-
90
90
99
99
Percent
D 1 sso 1 ved
1
1
87
89
100+
100+
61
61
-
1
1
100
100+
66
66
18
. 19
-
92
92
100+
100+
.Frequency of Detection
I n Tota 1 Fract i on (%)
»
72
53
77
3
77
18
77
75
7
77
77
                        47

-------
                             Table  13b (Cont.)
            Total  Recoverable and Dissolved Metals Concentration
                as a Percent of Total  Metals Concentration:*
                       Non-Priority Pollutant Metals
                           (Based on 60 samples)

Strontium
Tin2
Titanium
Vanadium
Yttr ium2

RMK = 0
RMK = RMK
RMK » 0
RMK = RMK
RMK " 0
RMK - RMK
RMK = 0
RMK = RMK
RMK = 0
RMK = RMK
Percent Tota 1
Recoverab 1 e
96
96
-
59
59
63
71
-
Percent
01 sso 1 ved
93
93
-
0
5
0
32
-
Frequency of Detection
1 n Tota 1 Fract i on ( % )
77
5
60
23
5
^Determined using only those samples with a detectable level of metal in
the total  fraction for greater than IOJ of the samples analyzed.

2Fewer than 10? of the samples had detectable levels of metal  In the
total  fraction.
     * 0:    Percentages have been calculated substituting zero for less
            than detectable values In the dissolved and total recoverable
            f ract I ons.
 RMK » RMK:  Percentages have been calculated substituting the detectable
            limit for less than detectable values In the dissolved and
            total recoverable fractions.

^Contamination suspected In the dissolved fraction.
                                  48

-------
                                 Table  14
                       Summary of Violations of EPA's
                          "Red Book" Criteria for
                     Non-Priority Pollutant Metals (1)
                        (In undiluted Urban Runoff)
Meta 1
Bar I urn
Boron
1 ron
Manganese
Criteria
(ug/l )
1000 (2)
750 (3)
300 (4)
50 (4)
Number
of
Samp 1 es
60
60
60
60
Range of
Detected Va 1 ues
(ug/l )
10-320
10-180
300-69900
10-1620
% of Samples
in Violation
0
0
96
77
Detect I on
Limit
(ug/l )
10
10
20
10
 Violations based on total  metal fraction only,
^Domestic water supply (health)

 Long term Irrigation on sensitive crops

 Domestic water supplies (welfare)
                                   49

-------
from 40-740 ug/1.  Although dilution by receiving streams
and subsequent treatment of river water by drinking water
facilities would likely reduce these levels (particularly
since it is in the suspended form),  drinking water standard
violations are still possible under worst case conditions.
Such conditions would include cases where:  (1) the runoff
during a storm event was a large portion of the receiving
water flow, resulting in a dilution of less than 1 to 15;
(2) the preliminary sampling results were representative of
lead concentrations above drinking water supply intakes; and
(3) lead removal by public drinking water treatment facili-
ties was minimal. Specific risks to drinking water supplies
could be evaluated by confirmatory sampling during storm
events.
     In undiluted urban runoff, nickel concentrations ex-
ceed the human health criterion of 13.4 ug/1 (total nickel)
in 12 percent of the samples, with total detected nickel
concentrations ranging from 20-60 ug/1.  Violations are ex-
pected to be less than the 12 percent figure after dilution
by receiving streams. Moreover, nickel is notconsidered a
significant human health problem in water because it is
poorly adsorbed by the body when ingested.  Inhalation of
nickel, especially nickel carbonyl,  poses the greatest risk
to human health.
     Lead, copper and zinc concentrations in undiluted run-
off exceed freshwater acute criteria in greater than 37 per-
cent of the samples, with the largest observed concentration
being less than 10 times the respective criteria.  Depending
upon receiving stream dilution, these pollutants could cause
harm to aquatic life.
                               50

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     Lead, copper and zinc concentrations in undiluted
runoff also exceed freshwater chronic criteria in greater
than 53 percent of the samples.  These criteria are
allowable levels for 24 hours.  Consequently, duration of
the storm event and receiving stream flow are both important
factors  needed to fully evaluate the significance of these
violations.  Since most storms last between 2 and 16 hours,
problems due to chronic criteria violations appear to be
unlikely.  The violations of acute criteria, however, could
be significant in longer term storms with low dilutions in
receiving waters.
     Only two priority pollutant metals (copper and zinc)
were present in dissolved forms, to any great extent.
     This screening approach does not account for the
long-term water quality impacts that might occur as a result
of the depositon of sediment and accumulation of toxic
metals in stream bottoms.  The sediments deposited as a
result of urban runoff may be a source of toxic metal pol-
lution due to deposition and resuspension.
     In undiluted urban runoff, two non-priority pollutant
metals (iron and manganese) exceed EPA's "Red Book" criteria
established to prevent brownish staining of laundry and
plumbing fixtures, and objectional taste in beverages. The
high levels of these elements found in urban runoff is not
unusual since the metals are ubiquitous in nature, and iron
is the fourth most abundant element in the earth's crust.
                              51

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                        REFERENCES
Athayde, D.N., et al.  1981.  Preliminary Results of the
    Nationwide Urban Runoff Program,  Volumes 1 and 2.
    Draft Report.  U.S. Environmental Protection Agency,
    Water Planning Division, Washington,  D.C.

Dalton"Dalton"Newport.

    1981a.    Priority Pollutants in  Urban Stormwater  Run-
              off:  A Literature Review.   Draft Report.
              EPA Contract No.  68-01-6195, Work Assignment
              No. 1, Dalton'Dalton'Newport, Cleveland,
              Ohio.

    1981b.    Methods for Analysis of Initial  Nationwide
              Urban Runoff Program Data.   Draft Report.
              EPA Contract No.  68-01-6195, Work Assignment
              No. 1, Dalton'Dalton'Newport, Cleveland,
              Ohio.

Shelly, P.E.  1979.   Monitoring Requirements,  Methods,  and
    Costs for the Nationwide Urban Runoff Program.  Re-
    printed from the Areawide Assessment Procedures Manu-
    al.  EPA-600/9-76-014, U.S. Environmental  Protection
    Agency, Water Planning Division.  Washington, D.C.
                            52

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Sunderman, F.W., Jr.  1981.  Recent Research on Nickel Car'
    cinogenesis.  Environmental Health Perspectives,
    40:131-141.

U.S. Environmental Protection Agency.
    n.d.
Data Collection Quality Assurance for the
Nationwide Urban Runoff Program.  EPA, Water
Planning Division, Washington,  D.C.
    1980.     Nationwide Urban Runoff Program, Data Man-
              agement Procedures Manual.   Draft.   U.S.
              Environmental Protection Agency, Washington,
              D.C.  95 p.

    1978.     1978-1983 Work Plan for the Nationwide Urban
              Runoff Program.   U.S.  Environmental Protec-
              tion Agency, Water Planning Division, Wash-
              ington, D.C.  75 p.
Versar.
    1980a.    Monitoring of Toxic Pollutants in Urban Run-
              off:   A Guidance Manual.   U.S.  Environmental
              Protection Agency,  Office of Water Regula-
              tions and Standards.   Washington,  D.C.   65 p.

    1980b.    Quality Assurance for Laboratory Analysis of
              129 Priority Pollutants,  Interim Report.
              U.S.  Environmental  Protection Agency,  Office
              of Water Planning and Standards,  Washington,
              D.C.   63 p.
                             53

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     APPENDIX G



PROJECT DESCRIPTIONS
         G-l

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                                   APPENDIX G

                                    FOREWORD
     Descriptions for each of the twenty-eight NURP projects are presented in
this appendix.  The projects are presented in order by EPA Region number from
I through X.  There is at least one project in each region.

     Descriptions are organized in a uniform format.
                                       G-2

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NATIONWIDE URBAN RUNOFF PROGRAM

 NEW HAMPSHIRE WATER SUPPLY AND
  POLLUTION CONTROL COMMISION

           DURHAM, NH

          REGION I, EPA
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                                                                                                                        PHYSICAL DESCRIPTION
                              Introduction
The town of Durham, situated In Strafford County, Is located In southeastern
New Hamshlre, approximately twelve miles inland from the Atlantic seacoast.
Durham's topography consists of gently  rolling hills and streams with these
streams draining Into the Oyster River  and Oyster River estuary.

The Oyster River has been classified  "Class A° west of Mill Road and "Class B"
east of Mill Road.  The water quality standards require that Class A waters
be acceptable for public water supply after disinfection with no discharge
of wastewater allowed, and that "Class  B" waters be suitable for water supply
after adequate treatment with no wastewater to be discharged unless adequately
treated to maintain other classification parameters.  Beneficial uses of the
Oyster River include freshwater fishing, boating, and extensive shell fishing
in the tidal flats.

The present water quality of the Oyster River and Oyster River estuary is good.
However, it is Important to note the  high growth rate of coastal New Hamphire.
Strafford and Rockingham counties, which encompass the entire coastal region
of New Hampshire have increased In total population from 209,000 In 1970 to
259,000 in 1977.  This represents an  increase of 24 precent over seven years.
Recent economic conditions have continued or even spurred the present development
rate of the area.

Of concern to local and state agencies  Is the impacts that this rapid development
will have upon the entire coastal area, including water quality resources.

Also, on a statewide level, under statute RSA 149:8 the staff Is currently
developing regulations for construction operations involving earth changing;
including road building and repair, site  development and hydrologlc mod-
ifications.  Under these proposed requlations a permit would require the use,
as applicable, of best management practices to control erosion and sedimentation.
Included In the recommendations for new developments is a requirement that
the peak rate of runoff during and after site development should not exceed
that occur1ng before the undertaking  by more than about ten percent.  The
Durham study will aide developers, as well as regulatory agencies. In deter-
mining the best control alternatives  and management practices.
A.   Area

The town of Durham, situated In Strafford County, Is located in Southeastern New
Hampshire, approximately twelve miles inland from the Atlantic Seacoast.  The
total area of the Town comprises about 23.3 square miles of land and about 2.2
square miles of water.  Land use within the town is characterized as Institutional
with associated residential and commercial development.

B.   Population

In the northwesterly section of Durham, adjacent to the upper end of the Oyster
River estuary, are situated the grounds and buildings of the University of New
Hampshire.  The most dense residential and commercial development has taken place
in the area near the University.  Present population including University enrollment
Is 15,100 and has been projected to Increase to 22,500 in the year 2000.

C.   Drainage

Durham's topography Is typically New England with gently rolling hills and streams.
These streams drain to the Oyster River and Oyster River Estuary.

The Oyster River originates In the southern portion of Barrlngton, New Hampshire.
The river flows southeasterly through the Lee-Durham town borders and continues
east through the north central portion of Durham.  The river empties into the Great
Bay at Durham Point, and  is tidal up to the tide head dam In Durham at Route  108.
It drains an area of 32 square miles, (see map)

D.   Sewerage System

The existing sewage system serving the town of Durham and the University of New
Hampshire is completely separated and consists of lateral sewers, intercepting
sewers,  the Dover Road pumping Station and  force main, and  a primary wastewater
treatment plant.  The sewage  system contains  a total of  approximately  13.5 miles
of gravity sewers serving a tributary area  of  about 800  acres and approximately
3,000 feet of  18 Inch force main.

The  primary wastewater treatment plant  is currently being upgraded  to  secondary
treatment. The construction phase Is  approximately  151 complete.  The  wastewater
treatment plant discharges  into the low reaches  of  the Oyster River estuary.
                                       61-2
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         Sugar)oaf
         Mountain
          (3701 ft)
THE STATE UK NEW MAMPSItlUE
        Gl-4


                                    •—U • I - .' f I >\ T^UVv-'-i    1
                                    ;
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                              PROJECT AREA


 I.  Catchment Name - 2 Pte (Pettee Brook at Hadbury  Road)

    A.  Area - 106 acres

    B.  Population - 2600 persons

    C.  Drainage - Pettee Brook Is a tributary draining Into  the Oyster
        River.  Main channel 1s 2800 ft. at approximately  37  ft/mile
        slope In the channel.

    0.  Sewerage - Drainage area of catchment Is 100% separate storm
        sewers.  All of area is served by swales and ditches.

        Streets consist of 100 lane miles of asphalt In good  condition.

    E.  Land Use

        20 acres (192) Is .5 to 2 dwelling units per acre  urban residential.
        2.4 acres (12%) Is Impervious.

        16 acres (15%) Is >8 dwelling units per acre urban residential.
        1.76 acres (lit) is impervious.

        9 acres (8%) Is Central Business District.
        8.55 acres (951) Is impervious.

        6 acres (61) is Shopping Center Area.
        6 acres (1001) is impervious.

        55 acres (52%) is Urban Institution (Univ.  of NH).
        5.5 acres (10%) Is impervious.

         ~ 23%  imperviousness in entire drainage area.


II.  Catchment Name - 3 Pte (Pettee Brook at Alumni  Cntr.)

    A.  Area  -  615 acres

    B.  Population - 100 persons

    C.  Drainage - Pettee Brook is tributary draining Into the Oyster
        River.  Main channel is 15,800  ft. long at approximately
        42 ft/mile slope in  the channel.

    0.  Sewerage - Drainage area of catchment Is 15S separate storm
         sewers  and 85% no sewers.  All  of area is served by swales
        and ditches.
                                  Gl-6
          Street consist of 4.83 lane miles of asphalt and other materials.

      E.   Land Use

          30 acres (5%) is .5 to 2 dwelling units per acre urban residential.
          1.38 acres (5%) is impervious.

          10 acres (2%) Is Central Business District.
          9.5 acres (95%) is impervious.

          135 acres (22%) is Urban Parkland.
          .54 acres (<1%) is impervious.

          18.5 acres (3%) is Urban Institutional.
          3.09 acres (17%) is impervious

          90 acres (15%) is Agriculture.
          .84 acres (<1%) Is impervious.

          320 acres (52%) is Forest.
          .96 acres (<1%) is impervious

          11.5 acres (2%) is Mater, Lakes.
          0% impervious.

          ~ 3% Imperviousness in entire drainage area


III.   Catchment Name - 5 Oys (Oyster River at Tidehead Dam)

      A.   Area - 2181 acres

      B.   Population - 3600 persons

      C.   Drainage - Drainage into site consists of 20% separate storm
          sewers and 80% no sewers.  All of area is served by swales and
          ditches.

          Streets consist of 31  lane miles of asphalt in good condition.

      D.   Sewerage - See above.   80% of drainage is through subsurface
          systems.

      E.   Land Use

          430 acres (20%) .5 to  2 dwelling units per acre urban residential.
          25.8 acres (6%) is Impervious.

          5 acres (.2%) >8 dwelling units per acre urban residential.
          .5 acres (10%) Is impervious.
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          2 acres (.09%)  Centra] business District.
          1.9 acres  (95%) is  Impervious.
          8 acres (.41) Shopping Center.
          8 acres (loot)  is impervious.
          380 acres  (17*) Is  Urban Parkland.
          15 acres (4*) is  impervious.
          86b acres  (40%) is  Forest.
          02 Impervious.
          21 acres (U) is Mater. Lakes.
          OX impervious.
          200 acres  (9%)  is Urban Institutional.
          20 acres-(10%)  Is impervious.
          270 acres  (12%) Is  Agriculture.
         .<5% is impervious.
           ~^3X of entire drainage area is  impervious.
IV.   Catchment  Name  -  7 Oys  (Oyster River at Reservoir)
     A.   Area - 10,560 acres
     B.   Population  -  300 persons
     C.   Drainage -  100% of  area has no sewers.
         Streets consist of  78  lane-wiles with 62 lane-miles being
         asphalt in  good condition.
     0.   Sewerage -  Ho sewers.  Drainage is all through subsurface systems.
     £.   Land Use
         75 acres (1%) is  .5  to 2 dwelling units per acre urban residential.
         3.75 acres  (5%) is  impervious.
         2 acres (<}%) is Central Business District.
         1.9 acres (952) is  impervious.
         II acres (.11)  is Urban Industrial.
         8.25 acres  (75%)  is  Impervious.
         110 acres ([%)  is Urban Parkland.
         2.2 acres (2%)  is impervious.
        5 acres (<1%) is Urban institutional.
        .5 acres (10X) is impervious.
        26 acres (.2*) is Agriculture.
        .52 acres (2%) is impervious.
        10326 acres (982) is Forest.
        5 acres is impervious.
         ~.2% of entire drainage area Is Impervious
V.  Catchment Name - 1 Pkg (Shop and Save Parking Lot)
    A.  Area - .90 acres
    B.  Population - 0
    C.  Drainage - 1 Pkg Is a parking lot site drained entirely by
        separate storm sewers.
        Drainage area of the parking lot Is 1001 asphalt streets.
    D.  See above
    E.  Land Use
        40.000 ft2 ts Commercial Shopping Center of which
        36.000 ft2 (90%) is Impervious
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                                                 O

                                                 :z
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                                                 B
                                                                                         SCIIEhATIC OF  SAMPLING SITES
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                          Project Description
A.   Major objective

The final State of Hew Hampshire detailed 208 Hater  Quality Management Plan
stated that the major emphasis of the 208 statewide  effort is  to control
"existing and potential nonpoint source pollutions"  as  necessary to  "meet
the water quality goals of the state and the  Fishable.  Swlonable goal of
the Act."

The Durham HURP study is a continuation of the earlier  208 effort  and was
structured to meet the objectives outlined in the  final  208 plan.  The  project
was broken into two phases; Phase I  - Base Line Study and Phase II - Control
Measures Study.

Phases I had several specific objectives.   These were to 1) measure  the mass
loadings of urban runoff constituents during  Individual  storm  events, 2) measure
the impact of urban runoff upon the  receiving stream and relate this Impact to
possible violations of State Hater Quality Standards and 3) model  the Impact
of urban runoff upon the receiving estuary stream  and relate this  Impact to
possible violations of State Hater Quality Standards.

One full year's data base, encompassing any seasonal  variations which pay
exist, was obtained for Phase I.

Phase II of the study will begin with the cessation  of  the Phase I data base
collection.  The specific objectives of Phase II are to  1) measure the
effectiveness of urban runoff degradation control  measures in  terms of
cost versus mass loading reduction,  2) assess the  impact of urban  runoff
degradation control measures upon the receiving stream  and Us State Hater
Quality Standards classification and 3) model the  impact of urban  runoff
degradation control measures upon the receiving estuary  and Its State
(•later Quality Standards classification.

Phase II will also be one year in duration In order  to  encompass any seasonal
influences upun the Implanented control measures.  In the study area the State
felt that efforts to prevent or reduce storm  water pollution would be best
applied to developed areas in the Oyster River headwaters, since the Durham/
Tidal Oyster River area Is to a large extent  developed.  The study will con-
centrate on maintenance and operation practices that will attenuate or eliminate
the degree of upset to the natural hydrologic balance of the watershed caused
by urbanization In the loner Oyster  River basin.

After the quantitative impact of the storm water pollution from the developed
area has been estimated, the State feels that effective  planning could be
instituted by limiting the amount of stream degradation  that could be tolerated
during wet weather.  The town of Durham could then determine what  development
options are available based on the residuals  emitted from the  remaining
undeveloped Town area.
                                     Gl-12
B.   Methodologies

Presently there is little urban data base for the Town of Durham.  Basically.
this NURP study Initiated the Investigation of this phenomenon  in  the
New Hampshire coastal area.

In the data collection effort, the quantity, as well as  the quality, of  urban
runoff was examined.  The hydrological causal factors of storm  water runoff
were recorded in order to ascertain their role and importance in the phenomenon
of urban runoff.  These factors Include storm intensity, duration  and  frequency.

Land use within the study areas will also be characterized.  These parameters
are to be developed In relation to pollutant loadings results and  compared
with those of other studies In order to determine whether or not a correlat-
ing factor exists between land use and the amount of pollution  associated
with urban runoff.

Phase I consisted of gathering base line urban runoff data for  the selected
sub-catchments and the receiving stream.  Phase II will  consist of examining
these sub-catchments after the Implementation of control measures.  In this
way, the effectiveness of the control measures will be evaluated by calculat-
ing the difference in pollutant loads of the sub-catchments before and after
the Implementation of the selected control measures.

The cost-effectiveness of implementing control measures  will be assessed In
terms of total costs versus pollutant removal amount or  percent.   The  rela-
tionship examined will be unique to the land use characteristics of the
sub-catchments examined and to the hydrological stonuwater conditions
surrounding the storm events monitored.

Dry weather data was collected weekly for one year In the freshwater portion
of the receiving stream.   Receiving water stream data was also collected during
storm events for comparisons with dry weather, as well as State Water  Quality
Standards.  The purpose of these comparisons is, first,  to determine how
urban runoff and urban runoff control measures affect stream quality and,
second, to evaluate these changes with respect to possible State Hater
Quality Standard Violations.

Estuary monitoring 1s also conducted on a periodic basis.  The purpose of this
monitoring is to collect data in order to calibrate and  verify  the estuary
flushing model.   The flushing model will be used to assess the effects of urban
runoff and control measures upon estuary water quality.

C.  Monitoring

The study area consists of a section of the Oyster River drainage  basin
encompassing the downtown area of Durham, NH.  The monitoring program  covers
three in-town sub-catchments, the Oyster River and the Oyster River estuary.

One sub-catchment examined is a commercial parking lot in downtown Durham
(1 Pkg).   The second sub-catchment is larger and drains  on institutional-
commercial area of town (2 Pte).   A third sub-catchment  drains an  area that
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Is largely forest and agricultural land (3 Pte).   This station is necessary
to separate the upstream drainage from the downstream drainage.   In addition,
there are five stations to be monitored in the Oyster River and  Oyster River
estuary.  The two upstream stations are located at Impoundment sites in the
River, the lower of which separates the freshwater and tidal portions of
the River.  The remaining three stations are located in the Estuary.

There is one rain gage operated on the University of New Hamsphlre campus.
The gage 1s a Fisher-Porter model registering 0.1 inch increments of rainfall.
An additional rain gage was installed at the parking lot site.

The list of parameters examined in each sample Includes:  Biochemical Oyygen
Demand (BOD). Chemical Oyxgen Demand (COD), Nitrogen (NO? and NOi), Total
Phosphorus (P) and Chlorides (CL).  Metals analyzed for Include  Cadmium,
Lead, Chromium, Copper, Iron, Manganese, Nickel and Zinc.  This  dissolved
and suspended nature of each of the parameters was tested.   Temperature,
pll, dissolved oxygen and aklalinlty were also Included.
All monitoring sites, except those located in the estuary, have automatic
sampling equipment.  Following is a brief suimary of the types of flow
monitoring and automatic sampling equipment located at each site:
ISCO model 1870 Flow meter and ISCO model 1680 sampler.   Flow is measured
by a flume located at the outflow of the catch basin.

2 Pte

ISCO model 1870 Flow meter and ISCO model 1680 sampler.   Flow is measured
using a weir located in the culvert.

3 Pte

ISCO model 1870 Flow meter and ISCO model 1680 sampler.   Flow is measured
using a weir located at the upstream end of the culvert.
ISCO model 1870 Flow meter and ISCO model 1680 sampler with model 1640
actuater.  A rating curve was established at this site.  The equipment is
suspended in the fish ladder with a bubbler located at the dam.
ISCO model 1870 Flow meter and ISCO model 1680 sampler with model 1640 actuater.
Equipment Is located in gate house for the reservoir with bubbler located at
the dam.
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  NATIONWIDE URBAN RUNOFF PROGRAM

   MASSACHUSETTS DEPARTMENT OF
ENVIRONMENTAL QUALITY ENGINEERING

      LAKE QUINSIGAMOND, MA

          REGION I, EPA
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                              INTRODUCTION
Lake Quinsigamond is located  In  the heart of Worcester County, Massachusetts
and lies between the City of  Worcester and the Town of Shrewsbury.  The lake's
drainage basin encompasses portions of Worcester, Shrewsbury, BoyIton,  and
West Boylton, plus corners of Grafton and HiUbury.

Lake Quinsigamond lies in a north-south direction and is crossed by three major
highways:  Interstate 1-290,  Route 9 and U.S. Route 20.  Being situated in a
highly urban area, the lake supports multiple recreational uses Including
fishing, boating, water skiing and bathing.  The entire periphery of the lake
Is densely settled with many  private homes and some commercial establishments.

The objectives of the Lake Quinsigamond NURP program are to assess the  magnitude
and severity of storm water runoff pollution In the lake and Its tributaries;
assess the cost, impacts and  benefits of appropriate control techniques;
recommend a comprehensive pollution abatement program for the watershed in
order to protect, preserve, enhance and recover portions of the lake and Us
watershed for recreation, and propagation of fish and other aquatic life;
and provide data on the character of urban runoff. Its Impacts on a major
recreational  lake as a receiving water, and on the effectiveness of various
runoff control alternatives.
                                         62-2
                                                                                                                            PHYSICAL  DESCRIPTION
                                                                                                  A.   Area
Lake Quinsigamond Is located in the heart of Worcester County, Massachusetts,
between the city of Worcester and the town of Shrewsbury.  Worcester and Shrewsbury
are the two most populous municipalities in central Massachusetts.  The lake's
drainage basin also encompasses portions of the towns of BoyIs ton, West Boylston,
Grafton and Mlllbury.  The entire periphery of the lake is densely settled with
many private homes and some commercial establishments.  Two state parks, several
private beaches and marinas are located along the shorefront.  The central part
of the drainage basin Is highly developed and considerable construction is
occurring or Is planned in the basin as a whole.

Being situated in a highly urban area with convenient access, the lake supports
Intensive, multiple recreational uses.  These uses include fishing, SMI mining,
boating, waterskilng, and aesthetic enjoyment.  In addition, the lake recharges
an aquifer providing water supply for Shrewsbury's lakeside wells.

Lake Quinsigamond is separated Into two distinct sections:  the deep narrow
northern basin and the shallow southern basin known as Flint Pond.

The total area of the lake Is 772 acres comprised of 475 acres in the northern  .
basin and 297 acres in Flint Pond.  The Lake Quinsigamond drainage basin
occupies a total area of about 25 square miles (16,000 acres).  The lake has
a maximum depth of 92 feet and an average depth of 20.7 feet.  The lake is
approximately 5 miles long, with the width varying from 250 feet to nearly
a mile.  The lake volume is estimated at 688 million cubic feet.

The single outlet of the lake is located at Irish Dam with the outflow creating
the Blackstone River.  The major Inlet to the lake Is from a series of ponds
north of the main body of the lake.  Approximately 14 small tributaries also
feed the lake.  These tributaries drain sub-basins varying in size from less
than one square mile to over 5 square miles.

B.   Population

Worcester and Shrewsbury, which occupy the majority of the Lake QuinsIgamond
Basin, are the two most populous of the 27 municipalities in the Central
Massachusetts Regional Planning Commission 208 Planning Area.  In terms
of generalized economic and demographic trends, Shrewsbury Is characterized
as an area of moderate to high population growth and Industrial/commercial
expansion.  Boylston and West Boylston are characterized as areas of moderate
to high population growth but slow Industrial commercial expansion.  Worcester,
Grafton and Mlllbury are characterized as areas of slight decline or very slow
                                                                                                                                        G2-3

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population and industrial/comiuerical  growth.
or these areas are as follows:
Worcester
Shrewsbury
BoyIs ton
West BoyIs ton
Grafton
Mi II bury
   1975
171.859
 21.858
  3.318
  6.257
 10.584
12.103
            Existing and projected populations
           1985
        169.400
         24,200
          4,200
          6.750
         11.000
        13,200
The entire periphery of the lake is densely  settled with many private homes
and some commercial  establishments.

C.   Ural iiciije

The Lake Quinsigamond drainage basin is a headwater basin of the Blackstone
River, rising immediately to the east of that  river's  origin.  The Quinsigainond
Itiver is the lake's  outlet and flows to its  juncture with the Blackstone at
Fislierville pond in  the town of Grafton, MA.

Hie Blackstone River than carries the combined flows southeast into Rhode
Island and tlie Seekouk River, which is tidal and flows into the Providence
River and thence into Narragansett Bay.

Lake Quinsigamond lies in a region in which  approximately half of the average
annual precipitation eventually becomes streamflow, the remainder being  lost to
evapotranspiration.   The most thorough study of the surface hydrology of Lake
Quinsigaiuond and its tributary streams was carried out as part of the 1971 Water
Quality study done by Massachusetts Division of Water  Pollution Control.  The
discharge of the major tributaries was measured by current meter on three
occasions.  Of the fifteen feeder streams contributing flow to Lake Quinsigamond.
six contributed over 90 percent of the surface flow:   Tilly Brook, Newton Pond
Overflow. Bonnie Brook. South Meadow Brook,  Poor Farm  Brook, and Coal Mine
Brook.

A partial water balance was derived for the  lake using data points which may be
summarized as follows:
Outflow (0)
Evaporation (E)
Tributary Inflow (I)
0 t E - I
4/26/71
 38cfs
  3
 30.37
 10.63
6/30/71
  9cfs
  6.4
  9.94
  5.46
12/17/71
 47.2cfs
  1.5
 39.63
  9.07
Tim outflow plus evaporation exceeds the inflow by  the  amount  given  In  the  last
row.  That amount approximately equals the release  from storage plus  roundwater
inflow.  Pumping front the Shrewsbury we Ms near the lake intercepts  some of the
groundwater inflow to the lake and may, if their zones  of influence  intersect  the
lake boundaries, cause a groundwater withdrawal from tlie lake.
                               The amount of storuiwater runoff reaching Lake Quinsigamond is important since  it
                               is believed to have a significant pollutional impact.  Using the measured outflow
                               for the lake and the dry weather flow data gathered by MDWPC. an estimate of the
                               total stormwater runoff was made.  That estimate suggested that during the  four
                               month 1971 survey period, about 25 percent of the lake inflow was due to stonuwater
                               which entered the lake from the storm drains and feeder streams.

                               Lake Quinsigamond Is stratified from May through November, during which time the
                               water below the thennocline becomes trapped and remains in place until the  lake
                               becomes completely mixed during fall overturn.  The surface inflow generally mixes
                               with the epillmnion during stratification.  The detention time of water In  the
                               epllimnion has been estimated to be between 125 and 150 days.

                               D.   Sewerage System

                               The Lake Quinsigamond watershed is mixture of separate storm sewers and septic
                               tank systems.  Within recent years elimination of point sources has been attainted
                               by the construction of interceptor sewers and transmission lines which convey  the
                               wastewater out of the basin and southward to a regional treatment facility.  However,
                               there is evidence that sewage contamination is still occurring.  The sources of
                               the sewage contamination could be numerous.  In areas without sanitary.sewers,
                               house connections have been Identified as a source of sewage contamination.  In
                               general storm drains are constructed without a great deal of care to avoid  infiltration
                               and renegade sewage leaking from house connections has no difficulty reaching
                               the storm drains.  Additionally there way still be direct sewage connections draining
                               to storm drains or major points of leakage between neighboring sanitary and storm
                               lines.  Common manholes were a problem in the past and may still be allowing some
                               leakage.
                                        G2-4
                                                                                                                                          62-5

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                                                                             Poor Form
                                                                             Bcoot -
                                                                                                                                 ZOOO
                                                                                                   — Billing'. Brook
                                                                                                          —^~~" IO  Contour inlorvol


                                                                                                           / \  Somplt Stotton
                                                           Rout* 9-Molch Lin*
                                                                               Lake  Quinsigamond  North of Route 9
                                                                                                  GZ-7
G2-6

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                                                                                  (cont.)-   Bathymetric  Map of  Lal;e  Quinsigamond
                                         2000
                               —•— IO' Contour inlixal




                               / \  Saraplt Stalin*
                                                                                                                       -5    Oiplh contour in  leel





                                                                                                                       f ^   SompU  Slolion
o        IOOO      200O      3OOO
                                                                                               (c)   Flint Pond
Lake  Quinsigamond South Of  Route 9
                                                                                                        G2-9

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                          PROJECT AREA

  I.    Catchment Name - Jordan Pond (PI)
       A.   Area - 110 acres
       B.   Population -  1042 persons
       C.   Land Use
           13 acres (121) is 1/2 - 2 dwelling units  per acre residential
           74 acres (661) Is 2 - 8 dwelling units per  acre  residential
           18 acres (16%) Is commercial
            4 acres (41) Is  Industrial
            2 acres (21) Is Parkland
 II.    Catchment Name - Route 9 Manhole, within  Regatta Point fence at
       Police Station  (P2)
       A.   Area - 338 acres
       B.   Population - 2285 persons
       C.   Land Use
           138 acres (411)  Is 2 -8 dwelling units per  acre  residential
            21 acres (61) Is 9 * dwelling units per  acre  residential
            82 acres (241)  is Commercial
            36 acres (111)  Is Industrial
            40 acres (121)  Is Parkland
            2? acres (71) is Open Land
III.    Catchment Name - Manhole on Locust Ave (P3)
       A.   Area - 154 acres
       B.   Population -  1703 persons
                                   G2-10
          C.   Land Use
               131  acres (851) 1s 2 - 8 dwelling units per acre residential
                 2  acres (21) Is Comnerclal
                12  acres (81) Is Industrial
                 7  acres (51) Is Parkland
IV. -Catchment Name - Fitgerald Brook discharge to the Lake (P4)
          A.   Area - 601 acres
          B.   Population -   5491  persons
          C.   Land Use
          363 acres (601) Is 2 - 8 dwelling  units per acre residential
           33 acres (51) is 9 + dwelling units per acre residential
           13 acres (31) Is Commercial
            8 acres (21) is Industrial
          92 acres  (151) is Parkland
          92 acres  (151) Is Open Land
     V.    Catchment Name - Coal Mine Brook at Notre Dame Convent (P5)
          A.   Area - 100 acres
          B.   Population -  104  persons
          C.   Land Use
                8 acres (81) is 2 - 8 dwelling units per acre residential
               63 acres (631) Is Commercial
                9 acres (91) Is Parkland
               20 acres (201) Is Open Land
                                                                                                                                     G2-U

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VI.  Catchment Name - Tilly Brook at Harvey Place Manhole (P6)
          A.   Area - 1690 acres
          B.   Population -  2«4b  persons
          C.   Land Use
               171 acres (10X) Is 1/2 - 2 dwelling units per acre residential
               168 acres (10J) is 2 - 8 dv/ellin9 units per acre residential
               112 acres (7X)  is  Commercial
                 27 acres (2%)  is  Industrial
               «93 acres (53»)  is Parkland
                 99 acres (6%)  is  Open Land
                210 acres (12%)  is Wetlands
                 10  acres  (>1»)  is Lakes
 Note:  Orainaye  and  Sewerage Information for the Individual  sites was  not
 provided in time for inclusion in Report.
r_  .  . •„    ^	\ --••"•5?
   /V-^"* ~>V"i: <~--'£f "3
 a^fe^if^i
 A^%«2B3fc
                                           G2-12
                                                                                                                                         G2-13

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                                                                                                         S3
                                                           1-290"
                                                        —Main Sl.-
   COAL MINE BRK.
  MEDICAL SCHOOL
    STORM DRAIN

WORCESTER
   BELMONT HILL
   STORM DRAIN
fit 9	

SHREWSBURY
                                                       ...Rt. 20	

                                                       fllNT POHO

                                                       IRISH DAM
                                                         OUWSIGAMONO
                                                            RIVER
                                Oulnilganond Drdnaqo latin
                                       G2-14
                                                                                 Clark St.
                                                                                                                                              Newton  Pond
                                                                                       Rte.  70
                                                                                    Boylston ,St.
                                                                                             290
                                                                                           Poor Farm Brook

                                                                                         Eastmountaln St.
                                                                                               Plantation St.

                                                                                               Mohican St.-
                                                                                                                                              Edgewater Ave.
                                                                                                                                              Ridgeland Ave.
Rte 9
                                                                                     SAMPLING STATION LOCATIONS
                                                                                                       Southmeadow
                                                                                                          Brook
                                                                                                       Sunderland Rd.
                                                                                                Rte 20


                                                                                               Mass Pike Exit 11

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                          LAKE QUINS1GAHOHD

                          SAMPLING STATIOUS
                           Lake  Qulnsigamood
STA tl - Lake - 90'                        «*  J»-
SIA 12 - Lake - 60-                        fXA  112
STA » - Lake - 80'                        STA  83
STA 04 - Lake - 50'                        STA  015
STA 55 - Lake - Surface 3 290 Bridge        STA  01b-
STA 06 - Lake - Surface 6 Bte. 9 BridBe     STA  017-
STA 08 - Fitzgerald Brook           -       StA  018-
STA 09 - Coalniue Brook                    &xa  •**"
STA 010 - Poor Farm Brook                  S|IA  »zo~
        Newton Fond Outlet, •
        Laka @ Lincoln SC.
        Billings Brook
        O'Eara Brook
        Medical School Drain
        Tilly Brook
        Jordan Pond Outlet
        Beloonc Street Drain
        Channel below Belmont
        Street Drain
                           flint Fond
STA tl - Pond - 3m, 1.5m
STA 02 - Pond - 8 surface
STA S3 - Pond - 4m. 2n
STA ft - Pond - 8 surface
STA 05 - Pond - 6 surface
STA 16 - South Meadow Brook
STA. tl - Inlet from Lake
         Qulnalgamond
STA 08 - Outlet of Food 3 Irish
         Dam
STA 09 - Bonnie Brook
                                     G2-16
                                                                                                               LAKE QUINSIGA210ND HUB? PROJECT
                                                                                                                 TRIBUTARY WATERSHED SUHVE7S
                                                                                                                      SAMPLING S1ATIOMS
                                                Poor  Farm Brook
                                                                                                           STA 01
                                                                                                           STA 02
                                                                                                           STA S3
                                                                                                           STA. 04
                                                                                                           STA 05
                                                                         at staff gaga behind Shrewsbury  Industrial Park
                                                                         at Route 70 bridge
                                                                         at staff gaga below Clark Street
                                                                         at East Mountain Street, below golf course
                                                                         at Hospital Drive (Usst Boylston)
                                                                                           Coalmine Brook
                STA 16 t   at Lake Avenue at gage
                STA 07 :   at Plantation Street
                STA. 13 I   below culvert at llotre Dame convent entrance
                STA 09 >   confluence with I-290/Llncoln Plaza drain -
                          Notre Dame property
                STA 010:   at culvert below 1-290
Fitzgerald Brook
                                                                                           O'Uara Brook
                                                                                           Tilly Brook
                STA 011:   at staff gage on Lake Aveaue
                STA 012:   below Coburn Avenue
                                                                                                           STA 013:  at staff gage oa culvert behind  17 Uhitla Drive
                STA 014:   West BrooU at Main Street
                STA 01S:   Outlet of Kill Pond
                STA 016:   at culvert above Spag's parking lot
                STA 017:   at staff gage on Hervey Place drain
South Meadow Brook
                                                                                                           STA f18:
                                                                                                           STA 019:
                                                                                                           STA 020:
                                                                         at Route  9
                                                                         at Oak Street betwaen Dclphen Ed.  and Judlck St.
                                                                         at staff  gage at South Quinslgamond Avenue
                                                                                                                               G2-17

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          TlO Poor F*rro ErooV.
                             \
   LI 2  10 Lake Oulnslgaraond
LOS 40 Lake nulnsiganon
                     1-290

       T09 Coalmine Broo
        Til  Houton  Pond  Outlet




   Main Street

-LO1 90  Lake puinslgamond
  T16 Ke-'.lcal School Oral


 T19 Belnont Street Drain

                    RI 9"
 T20 Channel below
   Biilnnnt Street drain
  -L02 60 Lake Ouinsiqamond

   .T 17 Tlllt Brook
     -L06 10 Lake Ouinslqaraond
  , L03 60 Lake Oulnslgamond
        TOB Fitzgera'd Brool:
        T21 Olr-1 Street 'irrok
  _   F07  Inlet  from L.Oulnslo-

      L04 SO Lat-" pulnsigaroond
     T22 Brlddle  Path Storm  Drain


              F05 5 Flint ""ond

                 T1S O'llara Brook
                                          TIB Jordan Pond Outlet
                                F03 IS Flint Fond-

                                      H0° nonnln i;rook'
                    1106  Bouthir.eedou Brook

                               F02 S Flint Pond



                                   F04 5 Flint PC



                                 FOB Irish Dam O
                                                                                                               LAKE QUniSlGAHONB SEDIMENT SAMPLING STATIONS
Lake QuinsIgssiond at Deep  Station tl

Lake Qulnsigamond at Deep  Station ' 92

Lake Qulnslgamohd at Deep  Station J3

Lake Qulnsigamond at Deep  Station J4

Lake Qulnslgaiaond above Lincoln Street

Medical School Drain

Channel below Belmont Street Drain

Mouth of Fitzgerald Brook

Mouth of Coalmine Brook

Confluence of Coalmine Brook and 1TDA. culvert

Mouth of Poor Farm Brook

Flint Fond at Station tl

Flint Fond at Station 13

Flint Fond at Station 04

Open water in pond below South Meadow Brook

Bonnie Brook above railroad tracks, below railroad tracks, and at
    Creeper Hill Road
          LAKE AND TRIBUTARY SAMPLING STATION UTJTIONS
                                         62-18
                                                                                                                                     G2-19

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                                    PROBLEM
A.  local Definition

    During the 1950's, Lake Quinsigamond was  by far the most  heavily  fished
    body of water In Massachusetts.   During the average opening weekend of
    the fishing season the lake supported considerably more angling trips
    than that which the majority of  Massachusetts'  waters  supported during
    the entire season.  The tremendous  fishing  use  of the  lake was as a
    result of its good water quality and heavy  stockings of rainbow, brown
    and brook trout by the Massachusetts Division of Fisheries and Game,
    supplemented by trout purchased  with contributions from Interested
    parties.

    The urbanization of the lake basin  resulted In  a variety  of water pollution
    problems  becoming-apparent  during the 1960's.   Fishing use of
    Lake Quinsigamond dropped off dramatically  as a result of the reduced
    water quality and concomitant drastic reduction in the stocking program.
    Concern about the deteriorating  water quality combined with the tremendous
    desire to utilize the recreational  assets of the lake produced widespread
    concern for the future of Lake Quinsigamond.  Consequently, over a several
    year period in the late 1960's and  early  1970's. investigations of the
    water quality of the lake and its feeder  streams were undertaken by
    state and local agencies, conservation groups,  university departments
    and private citizens.  These efforts were successful in defining the more
    conspicuous pollution sources and in providing  water quality data.

    The point sources of municipal and  Industrial pollution were recognized,
    and effective abatement measures Implemented.   Most significant among
    these was the establishment of the  Upper Blackstone Water Pollution
    Abatement District and construction of its  regional treatment plants at
    Millbury, discharging to the Blackstone River.  This resulted In connec-
    tion of most point sources  in the Lake Quinslgamond Basin to a system
    which conveys the wastes southward  and out  of the basin.  A major point
    source in the basin will be eliminated with the completion of a relief
    sewer by  the City of Worcester.

    As a result of the public's continuing concern  over Lake Quinsigamond's
    water quality, and for the  purposes of determining the magnitude of the
    nonpoint  sources on lake quality in a Massachusetts lake, the Massachusetts
    Division  of Hater Pollution Control (MDUPC)  selected Lake Quinslgamond
    for a comprehensive study during 1971.  The eight month study included a
    regular sampling program of 30 lake and tributary stations, flow measure-
    ments of the tributaries, and special  studies of photosynthesis, fish
    populations dud lake sediments.

    The 19/1  study concluded that significant Impact was being caused by
    urban runoff entering Lake  Quinslgamond.  Specific problems cited were
    the large quantities of nutrients and suspended solids carried In by
    urban runoff plus runoff-induced degradation of the lake's bacteriological
    quality.   It was further concluded  that intensive development of the
    drainage basin had accelerated the  lake's natural aging process, and could
    limit the lake's future recreational value.

                                        G2-20
    The findings of the 1971 Lake Study, plus the increasing conspiciousness
    of urban runoff as point sources were eliminated, provided the impetus
    for additional actions.  Beach closures at Regatta Point on the lakeshore
    resulted in the construction of an earthen dam by the City of Worcester
    to reroute stormwater from Belmont Hill.  Worcester also Instituted an
    ongoing program, Including television Inspections, to detect illegal
    connections to storm sewers, which the City regards as a major problem.  A
    baseline survey was also conducted in 1977 by MDWPC which indicated that
    there were some Improvements In lake water quality.  It is believed that
    these Improvements are a result of the elimination of various point sources
    Pf pollution In the basin.

    However, In spite of the abatement of point sources, survey data indicates
    that certain pollutional Indices have shown little improvement over the
    abatement period.   In particular, the trophic status of the lake has, by
    certain measures,  shown little change.  This is thought to be a result of
    the urban runoff nutrient and BOD loads, which have replaced the point
    source loads as the urbanization and point-source abatement have proceeded
    simultaneously.  Substantial growth Is projected for the basin, and the
    question of what the ultimate Impact will be on the lake Is one of extreme
    Importance.  Planning for recreational and aesthetic amenities in the
    region and public  water supply is highly contingent on the answer.

B.  Local  Perception

    The similarity of  Lake Quinslgamond to other lakes in Massachusetts, from
    a technical standpoint, was a primary consideration in the State's selec-
    tion of the project.   Massachusetts can be divided into four major
    physiographic regions based on Itmnological  factors.   Lake Quinslgamond
    is centrally located in the largest of these regions, termed the acidic
    fades of the central  and coastal areas.  By far the most common type
    in the State, this fades Is characterized by low pH, low total hardness,
    high iron, and high manganese.   The general  cause for these characteristics
    is the near absence of CaCOa in the rocks arid sediments.  Considering that
    the majority of the state's 2,859 lakes and  ponds lie In these fades, the
    regional significance of knowledge gained on lakes of the general limnological
    type of Lake Quinslgamond is considerable.

    Strong local commitment to Lake Quinsigamond has already been demonstrated
    by local expenditures of time and money in efforts to identify and abate
    pollution affecting the lake.  In addition,  the Lake Quinsigamond Commission.
    the Lake Quinslgamond Action Force of the Worcester Chamber of Commerce,
    and the Regional Environmental  Council have  all been involved in local and
    state efforts to clean up the lake.
                                       G2-21

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                          PROJECT  DESCRIPTION
A.  Ha Ior Oblecllve
The principle objective of  the  study  is to develop a basin management program.
In conjunction with the ongoing Clean Lakes project, which will  result in the
preservation and restoration  of Lake  Quinsigamond and Its tributary streams,
stressing In particular the water quality impacts of urban stormwater runoff.

Secondary objectives of the study are to develop information on the nature of
urban runoff affecting a major  urbanized lake basin.  This information Is to
be transferred to other areas with similar problems and to those areas where
It Is still  possible to avoid those problems.  An additional objective Is to
develop information on stonnwater pollution controls which can transferred to
other areas.

In developing Information on  the nature of urban runoff affecting an urbanized
basin, the State feels it's necessary to define the full range of existing and
potential  water quality problems caused by stonnwater runoff and to understand
the land use/beneficial  use interrelations mediated by stormwater runoff.  A
full range of viable stonnwater control alternatives will be defined to develop
a sound basin management program.

B.  Methodologies

The Lake Quinsigamond NURP  project has been divided Into two distinct phases,
the first of which took place during  the first year.  The first year effort
was Intended to define the  full  range of existing and potential  water quality
problems in  the Lake Quinsigamond basin and to gain a clear understanding of
the pollutant contibutions  from different land uses.

Before a sampling methodology was developed, a preliminary assessment of stonnwater
loads was performed using models.

The purpose  of the screening  was twofold.  First, It provided a basis for evaluating
the average  annual  stormwater pollutant load to the lake and what percentage  of the
total annual pollutant load to  the lake might be attributed to urban runoff.  The
screening also assisted in  the  selection of stormwater sampling stations.

Using the information developed through the screening methods, a stonnwater
sampling program was Identified.  This program was designed to provide sufficient
information  on the quality  and  mass loadings of pollutants discharged to Lake
Quinslyamond to allow correlations to be made between land use, storm events,
and resultant short and long  term impacts on lake water quality.

The data collected in the monitoring  effort will be input Into the same models
used for that screening effort  to come up with a refined set of land use-based
pollutant generation coefficients and an analysis of the Impacts of stonnwater
runoff on lake water quality.
This information on the impacts of stormwater runoff will be combined with the
criteria associated with the water quality goals for the lake to determine the
level of pollutant reduction required of stormwater runoff that will allow the
Lake to meet its assigned water quality classification.

Using other Information on historical rainfall, hydrcloglc design criteria such
as design storm volume, washoff depth, etc. will be established.  A range of
control alternatives including structural, non-structural and management controls
capable of meeting the design criteria will be defined.  This range of control
alternatives will be used In the development of a stormwater management plan  for
the watershed.

C.  Monitoring

In order to augment the existing data base and to more clearly establish cause
- effect relationships between wet weather events and in-lake water quality
Impacts on both a short and long-term basis, and expanded sampling program for
the lake and its tributaries was jointly developed by the Massachusetts Division
of Water Pollution Control 314 staff and DEQE/NURP staff.  Biweekly sampling  was
conducted at all in-lake stations and natural tributaries from the months of  April
to November 1980.  For the In-lake stations, chemical samples were collected  at
the surface, thermocline, 50 feet and bottom Intervals.  Dissolved oxygen and
temperature measurements were made at 10 foot intervals  in order to determine the
rate of oxygen depletion In the hypolimnlon and further define chemical trans-
formations and trends during the lake's period of stratification.  Stage/rating
curves were developed for the major  tributaries to the lake.  A survey of selected
major tributaries was conducted by the Worcester Department of Public Health  and
NURP staff.  This program is to aid  in characterizing and defining trends In  water
quality as they relate to land use and other tributary watershed characteristics
and in establishing water quality baselines for the tributaries.  Sampling at
these tributaries was conducted on a monthly basis from  September 1980 to July  1981.
Sediment samples were also collected to determine the nutrient and heavy metals
content.

Primary and Secondary Stonnwater Sampling Program

Stormwater sampling sites were located at six primary sites (P1-P6) and nine  secondary
sites (S1-S9).  Automatic water quality sampling devices and continuous flow  recording
devices were located at the primary  locations.  The secondary locations were  selected
for manual sampling and gaging with  the exception of Poor Farm Brook (S-9) which had
a continuous flow recording device for part of the sampling period.

The following Is a list of sampling  stations.  Primary sites are designated by  "f".

Designation                                  Location
    PI
Storm drain discharge to Jordan
Pond (Shrewsbury at Lakewood
Drive and Edgewood Avenue)
                                         G2-22
                                                                                                                                           G2-23

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     P2                                      Rt.  9 manhole (within Regatta  Point
                                             fence at  Police Station upstream of
                                             Be)wont St.  outfalls to the lake.
                                             Worcester side).

     P3                                      Manhole on Locust  Ave. (Worcester).

     P4                                      Fitzgerald Brook discharge to  the Lake
                                             across from Anna St. (Worcester).

     PS                                      Coal Mine Brook at Notre Dante  Convent
                                             (Worcester).

     P6                                      Tilly Brook  at Harvey Place Manhole
                                             (Shrewsbury).

There are ten secondary stonnwater sampling stations

A.   Poor Farm Brook at Rt. 70          F.   South Meadow Brook at Oak St.
B.   Poor Farm Brook at Mouth           G.   South Meadow Brook at Mouth
C.   Coalmine Brook at NDC              H.   O'llara Brook at Whitla Ave.
0.   Coalmine Brook at Plantation St.   I.   Billings  Brook at  N. Quinslgamond
E.   Coalmine Brook at Mouth            J.   Bonnie Brook at Creeper Hill Rd.

Catchment divisions were determined for all sampling locations  and for the  model
cells which cover the entire watershed.  Land uses were assessed for each catchment
division.

Mater quality, flow and rainfall records were collected over a  period from  June -
to Decanter, 1960.  Specific collection schemes were designed to cover various
types of composite and discrete samples.

Equipment

Each primary station was equipped with continuous automatic flow (liquid level)
recording devices.  Each site designated as a secondary station had sampling
and flow gaging conducted by manual means.

Water quality samples were taken at the primary stations using  Manning automatic
samplers collecting discrete and sequential samples over a specified period of
lime.  The sampler used a vacuum pump to minimize agitation of  the sample.   It
was driven by standard 12 volt batteries.  Samplers were set to initiate sampling
at the first significant increase in flow caused  by storm runoff.

0.  Controls

Several alternative control strategies will be evaluated using  modeling techniques.
                                        G2-24

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 NATIONWIDE URBAN RUNOFF PROGRAM
   MASSACHUSETTS DEPARTMENT OF
ENVIRONMENTAL QUALITY ENGINEERING
   MYSTIC RIVER, WATERSHED, MA
          REGION I, EPA
              G3-1

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                              INTRODUCTION
                                                                                                                         PHYSICAL DESCRIPTION
The Aberjona River Basin Is located  to  the north of Boston, Massachusetts and
comprises the largest tributary area to the Hystlc River watershed.  Aberjona
River empties into the Upper Hystlc  Lake which In turn becomes the headwaters
of the Hystlc River.  During the two decades from 1950 to 1970 this area under-
went a tremendous urban expansion.   Population increased by approximately
sixty percent and the total acreage  under some fora of urban land use climbed
to nearly fifty percent of the available land area.  Although the pace of
urbanization and population growth has  slackened somewhat. It is estimated
that nearly sixty percent of the drainage area to the Upper Mystic Lake will
be developed by the mid 1990's.

At present the water quality conditions throughout the Aberjona River system
and In the Upper Mystic Lake are generally below the standards assigned by
the Massachusetts Division of Water  Pollution Control and fall short of the
quality desired by the local populace.   As the level of urbanization and the
area population Increase, the demand for Improved water quality conditions
and expanded recreational opportunities will continue to grow.  Recent and
on-going efforts at the state and local  level have been" directed towards eli-
minating the adverse Impacts of  point source discharges and past waste dispoal
practices.  The effects of urban runoff on water quality In the study area
have not yet been addressed and  remain  a major factor prohibiting the full
realization of recreational opportunities within the urban watershed.
A.   Area

     The Mystic River basin Is located to the north of Boston and covers
     approximately 62 square miles.  The Upper Mystic Lake Watershed, the
     study area, covers 28 square miles In the upper basin.  Most of this
     area, 25 square miles. Is drained by the Aberjona River and its tri-
     butaries; the remaining area drains directly Into the Upper Mystic Lake.

     The Upper Mystic Lake Itself has two shallow forebays. 6 to 8 feet in
     depth, with a joint surface area of 40 acres, which flow into the main
     body which has a surface area of 126 acres and a maximum depth of
     approximately 90 feet.  The lake Is a major recreational area serving
     residents within the watershed and from nearby communities.  The Metro-
     politan District Commission maintains a swimming facility  - "Sandy
     Beach" - In the northeastern corner of the main body.  There is also
     a private swimming facility at the Medford Boat Club near  the outlet.
     Boating Is also a popular activity.  Fishing was enjoyed In the past
     but the lake quality Is no longer suitable for game fish.

     The Mystic River basin In characterized by long, cold winters and short
     to medium length summers with rainy, nun Id, warm periods.  Average annual
     precipitation Is about forty-three Inches and Is distributed through the
     four seasons In approximately equal  Increments.

     Historical Information Indicates that storms with relatively long duration
     and moderate Intensity have more pronounced effects on the Mystic basin
     than short duration, high Intensity  storms.

 B.   Population

     In 1975, the population of the Upper Mystic Lake Watershed was  640,000.
     During the two decades from 1950 to  1970 this area  underwent a  tremendous
     uran expansion.  Population  Increased by approximately sixty percent  and
     the total acreage under  some  form of urban land use climbed to  nearly
     fifty percent of the  available  land  area.  Although the  pace of urbanization
     and population growth has slackened  somewhat.  It  Is estimated  that nearly
     sixty percent of the drainage area to the upper Mystic Lake will  be develop-
     ed by the mid 1990's.

 C.   Drainage

     The Mystic River Basin extends  northeast from Boston  Harbor  and is bordered
     on  the west  by the  Shawsheen  River Basin, on the  north by  the  Ipswich River
     Basin, and on the  south  by  the  Charles  River Basin.   The topography of the
     basin, which was formed  by  the  east  glacier  about  ten thousand  years  ago,
      Is  predominately rolling hills  and  flat lands containing swamps,  but  includes
     some  steep  and rocky areas.   Elevations range  from sea  level  to a few hun-
     dred  feet.   Above  the Amelia  Earhart Dam. the basin encompasses a drainage
     area  of  61.9 square miles.  Including 25 square miles  which Is  drained by
     the Aberjona River.
                                  63-2
                                                                                                                                 63-3

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Upper Mystic Basin

The Aberjona River Basin covers the northern hiU of  the Mystic Basin and
includes the true source of the Mystic river, although  the name 'Mystic* is
not applied to these waters until they pass through the Mystic Lakes.  The
Aberjona River has its origins In a marshy area to the  north of Reading Center
and then flows in a southerly direction towards Uoburn.  After crossing Route
129 in Reading the stream enters a swampy area and emerges as two separate
branches. .These two branches are re-united when the  Aberjona is channelized
through the commercial/industrial area currently undergoing re-development
in the vicinity of the Old Mlshauua Lake just north of  Route 128.

Halls Brook and its tributary. Willow Brook, rise  In  marsh land west of the
Aberjona.  Halls Brook first flows north until Us confluence with Ml How Brook.
It then turns east-northeast until it reaches New Boston Street In Uoburn. where
it again turns and flows southeast until Its confluence with the Aberjona River.
The drainage area of Halls Brook Is 2.9 square niles  of generally mild topo-
graphy with some swampy areas in the upper reaches.

Halls Brook and the Aberjona River formerly flowed  into the Mtshawun Lake but
the recent construction In that area has altered that drainage pattern.  Mishawuro
Lake has been largely filled and replaced by Halls Brook holding pond; Halls
Brook empties Into this pond.  The Aberjona has been  routed around this pond
and now joins Halls Brook at the pond outlet lamedlately north of Mishawun
Road.

Below Halls Brook the Aberjona flows south, passes under Route 128 and Olympia
Avenue and then enters a marshy area extending through  Cedar Street and down
to Mill Street.  This marshy area was formerly a large  cranberry bog.  The
marsh gives way to a well-defined stream channel and  flows past Washington
Street and Hintvale Avenue, shortly after which Sweetwater Brook joins the
river from the east.

Sweetwater Brook, which has a predominantly urban drainage area of 2.3 square
miles, rises in a marshy area adjacent to Main Street in Stonehan.  It flows
south for a short distance and then through an underground pipe for about
2000 feet.  After leaving the pipe Sweetwater Brook flows southwest In an
open channel until just east of Interstate Route 93.  from there the brook is
channeled through a manufacturing area and into the Aberjona River.

Below Sweetwater Brook the Aberjona River continues to  the south and enters
Winchester.  Throughout the upper part of Winchester, the river flows through
a relatively natural channel past Cross Street. Washington Street, the B&M
railroad and Swanton Street.  There is a small pond  Immediately upstream from
Cross Street.  Downstream of Swanton Street the river travels In an open channel
for a few hundred feet until reaching Winchester High School's athletic field.
Aberjona pond once existed where the athletic field  is  now.  The pond has been
filled and the river flows through three 7-foot diameter pipes beneath the
field.  Horn Pond Brook joins the Aberjona River below  the athletic field.
Horn Pond Brook has a total drainage area, above Wedge  Pond, of 10 square miles.
The outer parts of the Horn Pond Brook watershed are  drained by Shaker Glen.
Cununiiiys and Sucker Brooks.  Cunnings Brook and Shaker  Glen Brook rise in
                                  G3-4
•arshy areas  to  the north  and west of  Horn Pond,  respectively,  darning's Brook
meanders  in a southerly direction, while  Shaker Glen Brook generally flows
northwest  until  its confluence with Cunnings  Brook  to fora Fowle Brook.  Fowle
Brook  flows due  east where It empties  Into Horn Pond.  Sucker Brook rises to
the  south  and flows northeast to  Horn  Pond.

Horn Pond  covers « surface area of roughly 120 acres and is used for limited
recreational  purposes and  as a water supply source  for the Town of Uoburn.
In the  recent past its capacity was Increased by  raising its normal water
surface approxlnately six  feet.   Horn  Pond discharges through a weir structure
into Horn  Pond Brook, which then  flows in a southeasterly direction through
Wedge Pond to the Aberjona River.

Below Its  confluence with  Horn Pond Brook, the Aberjona enters Judkins Pond
and Mill Pond In Winchester Center.  The  outlet of  Hill Pond is configured
as a semi-circle step spillway that falls approximately six feet.   The river
continues  to  travel in • southerly direction  to the United States  Geological
Survey  guage  located a short distance  downstream.   An elevation change of
approximately ninety feet  is recorded  over a  distance ilightly more than eight
miles from the headwaters  in Reading to Upper Mystic Lake in Winchester.  As
the Aberjona  River nears the end of its length It makes a final bend to the
west, gaining  depth and width as  it enters the Upper Mystic Lake.

0.   Sewerage  System

     The upper Mystic Lake watershed is served entirely by separate storm
     sewers.
                                                                                                                                    GJ-5

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                                              in <
                                              i'
                                                                                      PROJECT AREA
I.   Catchment  Name  - EOPA  (36* storm drain outfall draining a SO acre
     residential  area).
     A.    Area  -  50  acres.
     B.    Population - 240  persons.
     C.    Drainage - Station  Is located at end of 36  Inch reinforced concrete
          pipe.   The area drained  is low density residential.  There are
          sidewalks, well-groomed  lawns, and trees.   The land is moderately
          sloped  towards the monitoring station and the streets are relatively
          clean.
     D.    Sewerage - Drainage  area of catchment is 70X separate storm sewers
          and 20% curbs and gutters.  SOX of this area has swales and ditches.
          30X Is  not separately sewered.  There are no combined sewers  In the
          area.   Streets consist of 2.5 miles of asphalt.
     E.    Land  Use
          50 acres (100X) is  .5 to 2 dwelling units/acre.
          8 acres (16X)  Is  Impervious.
II.   Catchment  Name  - EOPB  (manhole installation in 30* pipe draining an
     18 acre office  park).
     A.    Area  -  18  acres
     B.    Population - 0 persons live  in the catchment
     C.    Drainage - Station  is located at end of 30  inch reinforced concrete
          pipe  draining  an  18 acre office park.  There are well-groomed lawns,
          shrubs, and  trees throughout the park.  Basin has relatively  steep
          slope towards station.
     D.    Sewerage - Drainage area of catchment Is 1M separate storm sewers
          and 30* with no sewers.  There are no combined sewers in the  area.
          Streets consist of  2.5 miles of asphalt.
     E.    Land  Use
          18 acres (100X)  is  light industrial.
          12.5 acres (69X)  Is impervious.
                                                                                             G3-7
63-6

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             63-9


MYSTIC RIVER WATERSHED
                                        O End of  pipe

                                        £ In-stream

                                        O Rainfall
                                           recorder

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          UPPER
          MYSTIC
          LAKE
                                                                  UPPER BASIN
               IOWEK
               BASIN
ARLINGTON
     Oo» fim OWPC 1981
     Uuppvdby Ollie. ol Fvrong 0 Pio?om K
          feel •* Erwuarawi*
                                       G3-10
                                                                                                                            PROJECT  DESCRIPTION
A.   Major Objectives

     The project was designed to build upon the existing data base to fully
     define the urban runoff problem In the Mystic River Basin and work
     towards Us solution.

     The major objectives are to Identify the characteristics of urban runoff
     and their Impacts on receiving water quality In the Aberjona River and
     Upper Mystic Lake and to recommend control strategies and management prac-
     tices needed for restoration of the Upper Mystic Lake.

     There are several Intermediate objectives.  These are to assess the relative
     Importance of pollutants carried by urban runoff in relation to other
     pollution sources, to evaluate the costs, effectiveness and practicality of
     various procedures suggested as a means of improving the receiving water
     quality, and to Illustrate how the data collected and the knowledge gained
     In this effort can be applied to urban runoff problems in other areas of
     the region and nation.

B.   Methodologies

     To fulfill the goals outlined for the program, the hydrologlc system was
     broken down  into several similar subsystems for analysis, namely: precipi-
     tation, pollutant generation, stream transport, and  lake processes.

     Precipitation  Is the basic driving for runoff,  infiltration  and stresnflow.
     The  statistical characteristics of the long-term observed precipitation at
     local gauges were determined describing  storm depth  duration  and  intensity
     and  the  Interval between storms, using a rainfall  simulation  logarithm.
     This Information  Is  used as rainfall  Input data for  the  runoff  simulation
     model discussed below.

     The  pollutant  generation subsystem uses  the  STORM model  to represent  the
     accumulation,  washoff,  and transport of  pollutant  species  from  the  land
     surface  of the study area  to  the Aberjona River and  Its  major tributaries.
     The  Upper  Mystic  Lake  watershed  was divided  into eight  sub-basins for
     analysis with  the contibutlng acreage  defined in terras of  five  land use
     categories.  The  results of the  STORM simulation give a  long-term record
     of flow  and pollutant  load Into  the Aberjona River from  the  various sub-
     basins.

     During the stream transport component of the analysis the existing  and
     potential  wet  weather pollution  problems are Identified  with the urban
      runoff contribution to these  problems separated from other factors.
      To accomplish  this  the RWQM is being  applied to the Aberjona River  with
      the 6 mile system divided  Into 12 reaches.   A number of pollutants  are
      being simulated, including BOD.  NBOD.  0.0.,  phosphorus and coliform.   The
      results  of this simulation can be expressed as loadings to the Upper  Mystic
      Lake.  RHQM will also be used to evauate a number  of control options.
                                                                                                                                       G3-11

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     lite objectives of the lake processes component are:

     1)   to Increase understanding of  the chemical, physical and biological
          processes which control  water quality conditions  in the Upper Mystic
          Lake (UML), relating those conditions to water uses of concern;

     2)   to assess the contribution of urban runoff relative to other sources;
          and

     3)   to predict lake quality  response to various control options.

     The analysis Includes a number of  key factors including: hydraulic flushing
     rates and retention time; in-lake  circulation patterns; relative thermal
     resistence to nixing; oxygen  distribution and depletion; In-lake pollutant
     cycling; trophic state; buffering  capacity; population dynamics, and;
     bacteriology.

     The analysis will compare wet-weather response conditions to baseline or
     dry-weather conditions.  Lake conditions that can be controlled through
     application of urban runoff and lake restoration practices are being
     determined.

C.   Monitoring

     Wet-weather sampling at end of pipe and instream stations was conducted by
     the selected consultant.  The existing sampling programs of the Department
     of Environmental Quality Engineering and the Metropolitan District Commission
     were modified to meet the project  needs.

     The end of pipes sites represent major land use types  In the watershed.  The
     instrean sites segment the Aberjona into subbasins for the runoff nodel and
     reaches for the river quality. The sites for In-lake  sampling are shown
     on Figure 2.  Precipitation is being monitored at four sites.

     The sampling program on the lake  includes wet weather  physical/chemical
     sampling 24, 48 and 72 hours  after the end of the storm event, dry weather
     physical/chemical sampling, circulation studies, benthic sampling, phyto-
     plankton and zooplankton surveys,  fish population surveys, and fish flesh.

     The lake sampling program includes 5 inlake stations and two tributary
     stations.  The Inlake sites are located between the forebays and main
     basin, at the beach, at the deephole and at the outlet and are designed to
     track water quality conditions throughout the system.

     The data collection strategy  for  the end of pipe and instream sites is
     presented in Table 2.

     Equipment

     Precipitation is being monitored  using Weather Measure, Inc. P521 event
     recorders, P501-I tipping ticket  bucket rain gauges and Balfour gauges.
     Al the end of pipe and Instrean stations, permanent installations are
     maintained consisting of Manning  S4040-2 discrete samplers and Manning
               uj*ras?n!c l(*el recorders.  Lake samples -ere taken manually
     at various time intervals using a Keoraerer sampler.  In the shallow
     upper portions of the Upper Hystic Lake where maxlmin depths are less
     thSMk.  !£• ST fJl-ere u«sn fro° **depths-  In the o«ln bod* °f
     the lake, where depths up to 82 feet nay be encountered, sanples were
     taken at three depths in five locations.
0.   Control
     Evaluation of control technologies and nanagement strategies will be
     carried out using the sane package of simulation nodels as described
     above.
                                    G3-12
                                                                                                                                   G3-13

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                                                                                                                                            PROBLEM
TABLE 1: Sampling Strategy Summary •
Site
(OP A







FOP e


IS 1





Description
36' storm driln outdl 1
draining 1 SO acre
residential area





outfall installation In
30* P'pe draining an 13
acre office park
Aberjona River at Nishawua
Rd. with an upstren drain-
age area of 4,157 acres
•Men lulatei the impacts
Of pot Industrial waste
disposal practices In the
upper basin
Equipment
flow: automatic liquid
le
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The 208 program, undertaken by the Metropolitan Area Planning Council
(HAPC). investigated storm-related (combined sewer  overlfows and urban
runoff) water quality problems in the Mystic River  Basin.   Under this
effort, the stormwater collection systems In the Mystic  Basin communities
were inventoried and mapped.  An attempt was then made to  quantify the
water quality impacts of these collection systems in order to Identify
the most significant systems and discharges.

The OUPC completed wet-weather surveys In the fall  of 1977.   Data were
collected on six stations In the basin, 5 of which  were  storm drains and
1 was a combined sewer overflow, for the first four hours  of a storm.

The Upper Mystic Lake has also been studied In detail.  In 1974-1975.  the
OUPC conducted a one-year intensive study of the Upper Mystic Lake with
monthly samplings at its Inlets, deep hole, and outlet.  The study focused
on the limnology of the lake and the causes of Its  eutrophic state.

The above survey Is indicative of the importance of this urban watershed
and of the attention that has been directed towards various  water resource
problems in the Aberjona River and Upper Mystic Lake watersheds.
                               GJ-16

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     NATIONWIDE URBAN RUNOFF PROGRAM



LONG ISLAND REGIONAL PLANNING COMMISSION





          LONG ISLAND, NEW YORK



              REGION I, EPA
                  G4-1

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                                 INTRODUCTION
Groundwater is the sole source  of  fresh water for the more than 2.7 million
residents of Nassau and Suffolk Counties on Long Island, N.Y. (Figure 1).
Under natural  conditions,  the groundwater reservior 1s recharged only by
local precipitation seeping  from the land surface to the water table.  Since
the 1920's, when Nassau County  began to experience rapid urbanization, the
construction of highways and parkways, houses, shopping centers, industrial
parks, and street and sidewalks in areas that had been farmland has contin-
uously reduced the amount  of land  surface through which precipitation can
infiltrate to the water table.   After urbanization, storm runoff from the
paved surfaces was carried to coastal waters through storm sewers, which
resulted in a  substantial  loss  of  recharge to the groundwater resevoir.

Ulicn Nassau County recognized that natural recharge was being lost, it began,
In 1935, to excavate large basins  to impound stormwater so that the water
could infiltrate to the groundwater reservoir through the permeable sand and
gravel beds that underlie  Long  Island.  The use of stormwater basins not only
helped to conserve storm runoff and to augment the groundwater supply, but
also eliminated the need for long, costly trunk storm sewers to carry runoff
to coastal waters.  The concept was adopted throughout Suffolk County some
years later.  In spite of  these efforts, there remain significant areas not
served by recharge basins, and, therefore, relatively large quantities of
runoff are still discharged  to  bays.

Investigations of the results of stormwater runoff management practices con-
ducted during the Long Island 208  Study identified major deleterious effects
of runoff upon surface waters and  possible significant impacts upon ground-
water.  With respect to surface waters, the major concerns are the potential
impacts upon use of the embayments for contact recreation, a use presently
widespread, and both existing and  future closures of shellfish areas for
health reasons.  With respect to groundwater, a major concern is the suspected
organic chemical contamination  of  the drinking water supply from runoff.
                                   G4-2
                                                                                                                            PHYSICAL DESCRIPTION
                                                                                              A.  Area
Long Island, the eastern-most part of New York State, extends east-
northeastward roughly parallel to the coastline.  The study area, Nassau and
Suffolk Counties, is bounded on the narth by Long Island sound, on the east
and south by the Atlantic Ocean, and on the west by Queens County which is
one of the five boroughs of New York City (Figure 1).  The primary land use
is residential but significant portions of the two counties is given to in-
dustrial and commercial uses.  Farming is also a major land use, particularly
In the central and eastern sections of Suffolk County.  The Inland fresh
waters, particularly In Suffolk County, have an abundance of trout and other
Important sport fish.  Estuarine marshes and the off-shore waters abound In
a variety of shell- and finflsh.

B.  Population

Nassau and Suffolk Counties occupy one-sixth of the land area of the New York
Metropolitan Region, and have been two of the fastest growing counties in the
United States since the end of World Mar II.  In 1960, the combined Nassau
and Suffolk population of two million persons was one-eighth of the total
Regional population of sixteen million.  The present population of the bi-
county area is in excess of 2.7 million people.

C.  Drainage

Long Island is underlain by a thick southward-dipping wedge of rock materials
that consist mainly of sand, silt, clay, and gravel.  These loose materials
are underlain by dense crystalline bedrock that does not store or transmit
significant quantities of water.  The groundwater reservoir Is within the
loose (unconsolidated) materials above bedrock and ranges in thickness from
zero to northern Queens County, were bedrock is exposed to more than 2,000 feet
in south-central Suffolk County.  Of the total precipitation on the island
(which averages about 44 Inches per year), approximately half or 600 million
gallons per day recharges the groundwater reservoir In Nassau and Suffolk
Counties.  Natural runoff discharged to surface waters accounts for only
5-10 percent of the precipitation, but in urbanized areas of the two counties
runoff is much greater.  As a result of the topography, all the southward
flowing streams have gentle gradients that average about 10 feet per mile
throughout most of their reaches.  The northward flowing streams generally
have steeper gradients that average about 20-40 feet per mile.

D.  Sewerage System

Because of differences in the degree of development in the two counties, and
the Inherently fixed nature of the existing Nassau system, treatment emphasis
differs not only by the hydrogeologlc zone but also by administrative area.
In Nassau, the major options concern treatment plant locations and effluent
disposal; in Suffolk, the major options concern an Identification of those
                                                                                                                                    G4-3

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areas that should be sewered as well as the siting of treatment facilities
and effluent discharges.

In addition, Nassau and Suffolk are discussed separately because their munic-
ipal wastewater treatment needs differ. Nassau County Is highly developed;
according to the 208 population estimates, the county population Is approxi-
mately 96 percent of saturation or zoned capacity, and is projected to reach
98 percent by the year 1995. Suffolk's population, on the other hand, is
currently at 52 percent of saturation and'is expected to Increase to 71 per-
cent by 1995. Nassau County has 23 existing domestic wastewater treatment
facilities, and major new construction is not anticipated except where'
expansion and upgrading of existing facilities Is necessary.  Suffolk County
has 105 small domestic treatment facilities in operation, and one major facil-
ity (30 MGD) under construction. Nassau's domestic treatment facilities are
generally large scale, treating up to 60 million gallons per day (MGD), but a
typical Suffolk County domestic wastewater treatment plant treats less than
one MGD, with the largest treating only approximately two MGD.

Surface water quality considerations also dictate different approaches in the
61-county Region. Marine water quality in Nassau County and western Suffolk
is Influenced by the effects of New York City discharge. In eastern Suffolk,
agricultural uses impact river and bay quality. A final reason for separate
consideration of the two counties concerns their degree of urbanization:
Nassau and western Suffolk Counties are highly urbanized, while eastern
Suffolk is essentially rural and agricultural In nature.
                           G4-4
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I 03330

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                                PROJECT AREA

I.     Catchment Name - Bayville (Perry Ave.)
      A.  Area - 65.6 acres.
      B.  Population - 612 persons.
      C.  Drainage - This catchment area has  a representative slope of
         40  feet/mile, 50% served with curbs and  gutters.  The storm sewers
         approximate a 40 feet/mile slope and extend  3500  feet.
      D.  Sewerage - Drainage area of catchment is 100%  separate storm sewers.
         Streets consist of 3.9 lane-miles of asphalt,.60% of which is in
         good condition and 40% of which is  in fair condition.
      E.  Land Use
         65.6 acres (100%) is 2.5 to 8 dwelling units per  acre urban resi-
         dential of which 9.8 acres (15%) is impervious.
II.    Catchment Name - Unqua Pond (Massapequa)
      A.  Area - 298.5 acres.
      B.  Population - 9492 persons.
      C.  Drainage - This catchment area has  a representative slope of
         20  feet/mile, 100% served with curbs and gutters.  The storm sewers
         approximate a 20 feet/mile slope and extend  2800  feet.
      D.  Sewerage - Drainage area of the catchment is 000% separate storm
         sewers.
         Streets consist of 46.6 lane-miles of asphalt, 100% of which is in
         good condition, and 3 lane-miles of concrete,  of  which 100% is in
         good condition.
      E.  Land Use
         253 acres  (85%) is 2.5 to 8 dwelling units per acre urban resi-
         dential, of which 40 acres (16%) is impervious.
          15  acres (5%) is Shopping Center of which 14 acres  (93%)  is
          impervious.
          30  acres (10%)  is Urban Parkland or Open Space of which 4 acres (13%)
          is  impervious.
                                      G4-6
III.  Catchment Name - Carl Is River Street Sweeping
      A.   Area - 73 acres.
      B.   Population - 939  persons.
      C.   Drainage - This catchment area has a representative slope of
          1.7 feet/mile,  81% served with curbs and gutters.   The channel
          approximates a  1.7 feet/mile slope and extends 4725 feet.
      D.   Sewerage - Drainage area of the catchment is 1002 separate storm
          sewers.
          Streets.consist of 9.5 lane-miles of asphalt. 902 of which Is in
          good condition, 7% of which is In fair condition,  and 3% of which
          Is In poor condition.
      E.   Land Use
          73 acres (100%) Is 2.5 to 8 dwelling units per acre urban residen-
          tial, of-which  14.5 acres (202) is Impervious.
IV.   Catchment Name - Carlls River Street Sweeping Control
      A.   Area - 64 acres.
      B.   Population - 925  persons.
      C.   Drainage - This catchment area has a representative slope of
          1.7 feet/mile,  93% served with curbs and gutters.   The channel
          approximates a  1.9 feet/mile slope and extends 2775 feet.
      D.   Sewerage - Drainage area of the catchment Is 100% separate storm
          sewers.
          Streets  consist of 7.98 lane-miles of asphalt, 90% of which is In
          good condition, 7% of which is in fair condition,  and 3% of which
          Is in poor condition.
      E.   Land Use
          64 acres (1002) is 2.5 to '8 dwelling units per acre urban resi-
          dential, of which 13 acres (20%) Is impervious.
V.    Catchment Name - Orowoc Creek
      A.   Area - 188 acres.
      B.   Population - 2,260 persons
      C.   Drainage - This catchment area has a representative slope of
          22 feet/mile, 852 served with curbs and gutters.  The channel
          approximates a  22 feet/mile slope and extends 1,700 feet.
                                                                                                                                     64-7

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     D.  Sewerage -  Drainage  area  of the catchment  is 100% separate storm
         sewers.

         Streets  consist of 16.45  lane-miles of asphalt, 86% of which is in
         good condition, 102  of which is fair condition, and 4% of which is
         in poor  condition.

     E.  Land Use -  154 acres  (82%)  is 2.5 to e dwelling units p?r acre urban residential,
         14 acres (8%) is urban institutional, and  18 acres (10%) «; the stream channel.
         26.3 acres  (14%) is  Impervious.

VI.   Catchment Name - lluntington  (Parking Lot)

      A.  Area -  39.19 acres.

      B.  Population - 0 persons.

      C.  Drainage - This catchment  area has a representative slope of
          84.5 feet/mile, 100% served with curbs and gutters.  The storm
          sewers  approximate  a 58  feet/mile slope and extend 1400 feet.

      0.  Sewerage - Drainage area of the catchment is 100% separate storm
          sewers.

          Streets consist of  27 lane-miles of asphalt of which 100% is in
          good condition.

      E.  Land Use

          39.19 acres (100%)  is Shopping Center, of which 39.19 acres (100%)
          is impervious.

VII.  Catchment Name - Plainview (Highway)

      A.  Area -  190 acres.

      B.  Population - 0 persons.

      C.  Drainage - This catchment  area has a representative slope of
          119 feet/mile, 85%  served  with curbs and  gutters and 15% served
          with swales and ditches.   The channel approximates a 206 feet/mile
          slope and  extends 2500 feet.

      D.  Sewerage -  Drainage  area of  the catchment is 100% separate storm
          sewers.

          Street  consist of .9 lane-miles of asphalt,  100% of which is in
          good condition, and  1.5  lane-miles of concrete, of which 1007, is
          In good condition.

      E.  Land Use

          178.1 acres (94%) is urban parkland or open  space.

          11.9 acres  (6%) Is Urban (other),  of which 11.9 acres  (100%)  is
          impervious.

                                        G4-8
VIII.  Catchment Name - Syosset  (Medium Density Residential)

       A.  Area - 28.2 acres.

       B.  Population - 238 persons.

       C.  Drainage - This catchment  area  has  a representative  slope of
           42.6 feet/mile, 100%  served with curbs  and  gutters.   The storm
           sewers approximate  a  42 feet/mile slope and extend 2100 feet.

       D.  Sewerage - Drainage area of the catchment is 100%  separate storm
           sewers.

           Streets consist of  2.45 lane-miles  of asphalt,  100%  of which is In
           good condition.

       E.  Land Use

           28.2 acres (100%) is  2.5 to 8 dwelling  units per acre urban resi-
           dential, of which 4.5 acres (15%) is impervious.

IX.    Catchment Name - Laurel Hollow (Low Density Residential)

       A.  Area - 100 acres.

       B.  Population - 117 persons.

       C.  Drainage - This catchment  area has  a representative  slope of
           519 feet/mile, 56%  served  with curbs and gutters and 44% served
           with swales and ditches.  The storm sewers approximate a 275 feet/
           mile slope and extend 2300 feet.

       D.  Sewerage - Drainage area of the catchment is 100%  separate storm
           sewers.

           Streets consist of 3.2 lane/miles of asphalt, 100% of which Is in
           good condition.

       E.  Land Use

           100 acres  (100%) is 0.5 to 2 dwelling units per acre urban resi-
         •  dential, of which 4.7 acres (4.7%)  is impervious.

X.     Catchment Name - Centereach

       A.  Area - 553 acres (But actual drainage area = 3.2 acres - see
           attached note.)

       B.  Population - 0  In actual drainage area (see attached note.)

       C.  Drainage - This catchment area has a representative slope of
           53  feet/mile,  100% served with curbs and gutters.   The storm
                                       G4-9

-------
          sewers  (main drainage channel) approximates  a  74  feet/mile slope and
          extend  2400 feet.

      D.   Sewerage  - Drainage area of the catchment is 100% separate storm
          sewers.

          Streets consist of 2.2 lane-miles of asphalt,  100% of which is in
          good condition.

      E.   Land Use

          543  acres (98.2%) is medium-density residential.

          10 acres  (1.8%) is urban commercial (linear  strip commercial develop-
          ment),  of which 3.2 acres (0.6%) is impervious.

Note:     Centereach Basin

          The  topographic drainage area surrounding the  Centereach Basin is
          553  acres, most of which is medium-density residnetial.  The actual
          area draining  into the basin, however, is only a  portion of the
          state road (Route 25 - Middle Country Road)  that  passes through the
          strip commercial portion of the area.  The shopping areas on both
          sides of  the highways have their own individual drainage systems and
          the  residential areas drain into other basins.  The basin being
          tested  is a state-owned basin that only drains that portion of the
          state-owned highway passing through the area (3.2 acres).  Thus,
          some of the data presented in part (X) might appear somewhat
          confusing.
                                     G4-10
                                   PROBLEM
A.  Local Definition (Government)
The Long Island 208 Study Indicated that stormwater runoff Is the major source
of bacterial loading to the marine waters of the area, and may contribute
significant quantities of pollutants to the groundwater reservoir through
stormwater recharge basins.

The groundwater reservoir has been designated the "sole-source aquifer" for
water supply In Nassau and Suffolk Counties, and the embayments of the area
are used for contact recreation, and are the major source of hard-shell clams
(Hercenaria mercenarla) In the United States.

In most areas of the region, runoff was found to contribute greater than
95 percent of the annual bacterial loading to the bays.  Since It Is the pre-
dominant source of colifonn bacteria, stormwater runoff Is very likely respon-
sible for much of the shellfish area closures on Long Island, and also
threatens many bathing beaches.  Surface water quality standards for several
bays cannot be consistently attained until the pollutant loading from storm-
water runoff 1s controlled.

Large quantities of pollutants in runoff are known to enter stormwater basins,*
which recharge an estimated 10% of all runoff on Long Island.  Little Is known,
however, about the composition and quantity of pollutants that reach the water
table after basin storage and exfiltratlon, or the effect of the soil cover
of a basin on the quality of percolate.  The 208 study seemed to indicate that
urban runoff is a significant source of inorganic chemicals, organic matter
and sediment, and may also be a significant source of organic chemclals.

New York State's concern was clearly indicated In Its New York State Mater
Quality Management Plan, which Identified urban stormwater management problems.
In particular, runoff problems on Long Island were Identified as requiring
special attention.  The State plan recommended additional monitoring, research,
and assessment in order to provide a better understanding of nonpolnt pollution
generation and transport, and a stronger technical basis for identifying and
solving runoff problems.
                                                                                                  Stormwater recharge basins on Long Island are open pits of various shapes
                                                                                                  and sizes excavated in moderately to highly permeable sand and gravel
                                                                                                  deposites of glacial origin.  Basins range from 0.1 to 30 acres in area
                                                                                                  and average 1 acre.  Basin depth average 10 feet, but some are deep as
                                                                                                  40 feet.  More of the water delivered to the basins consists of storm
                                                                                                  runoff from residential. Industrial, and commercial areas and from high-
                                                                                                  ways.  In 1978, more than 3,000 stormwater basins were In use in Nassau
                                                                                                  and Suffolk counties.
                                                                                                                                      G4-U

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B.  Local Perception (Public Awareness)

The forced closing of shellfish beds and  occasional  beach closings for health
reasons have caused stonns of protest at  the  time  the actions were taken.
There 1s contlning concern about shellfish bed  closures among both commercial
and recreational fishermen, and among all  citizens who regularly use the
embayments for contact recreation -  boating,  water skiing and swimming - as
well, for they rightfully see the shellfish restrictions as a sign of declin-
ing water quality which, If allowed  to continue, will sooner or later inter-
fere with other uses of the waters.   However, these  protests tend to be
triggered by specific events and ebb and  flow with particular crisis in water
quality.  The relationship of stormwater  runoff to these highly visible crisis
is complex and requires a technical  sophistication only a few random citizens-
in-the-street possess.  The connection between  pollutants In stormwater runoff
and contamination via recharge basins of  the  aquifers which provide drinking
water supply is even less visible and more complex technically.

As a result, the problem of controlling pollution  from stormwater runoff is
not one which has received a lot of  Independent, self-generated action, or
even attention, from the public.  However, public  participation and education
efforts under the original 208 Study were quite effective In alerting both
community leaders and Interested members  of the general publich to the poten-
tial dangers of stonnwater runoff.  Consequently there Is growing concern
for the need to control stormwater,  resulting 1n a very active publich advi-
sory group for NURP and a high degree of  citizen Interest In the results.
                                     G4-1Z
                             PROJECT DESCRIPTION
A.  Major Objectives

This project comprises sampling programs conducted at nine representative
sites to monitor the impact of different land uses upon storrawater runoff
loads, and to evaluate the effects of management practices on receiving water
quality.  Specifically, the project was designed to accomplish the following
objectives:

    1.  Groundwater:

        •  to determine the types and quantities of pollutants 1n runoff
           entering recharge basins (5 sites) and in percolating runoff
           entering the groundwater reservoir beneath basins;

        •  to evaluate the effects, If any, of the soil cover of recharge
           basins and basin management practices on the quality of preco-
           lating runoff;

    2.  Surface Waters:

        •  to identify the sources, concentrations and loadings for other
          . pollutants in addition to coliform bacteria and nutrients;

        •  to determine the practicality and cost-effectiveness of measures
           proposed for the control and/or treatment of urban runoff;

        •  to develop a stormwater management plan incorporating these
           measures to guide local municipalities.

B.  Methodologies

The overall program is being coordinated through the local 208 Agency (LIRPli)
as a cooperative effort of the local office of the United States Geological
Survey and the staffs of agencies represented on the Technical Advisory
Committee (TAC).  The TAC is comprised of the Nassau Departments of Health,
Publich Works and Planning, and the Suffolk County Hater Authority and
Department of Health Services.

Nassau County Is evaluating control measures at two sites.  The runoff
generated along Perry Avenue,  Bayvllle was previously uncontrolled and
flowed overland, south along Perry Avenue, directly Into Hill Neck Creek,
contiguous "to a bathing beach.  The majority of Hill Neck Creek had been
closed to shell fishing due primarily to stonnwater runoff bacteria loadings.
The method of control being evaluated in this drainage basin utilizes an
inline storage and leaching system, consisting of a series of perforated
catch basins, overflow leaching pools and perforated pipe.  Flow measurement
data and samples will be collected from three locations:  (1) in-flow Into
a catch basin, (2) in-flow Into overflow leaching pool (effluent of catch
basin), and (3) over-flow from whole sewerage system into a discharge outfall.
                                                                                                                                    G4-13

-------
At Unqua Pond, Massapcqua, the control  measure  to be evaluated is settling
and sedimentation in a natural impoundment.   Samples and  flow measurements
will be obtained immediately upstream of the  pond and at  the spillway dis-
charging to the marine waters.

The Suffolk County Department of Health Services is sampling stonnwater run-
off pollution mitigation measures:   (1) street  cleaning;  (2) energy dissipa-
tion at the discharge of a storm sewer  to maximize overland runoff and the
pollutant removal capabilities of wetlands; and, (3) the  pollutant filtering
potential of dried up portions of stream beds.  Two of the sites are located
on Carlls River, which is the freshwater stream with the  greatest base flow
discharging to western Great South  Bay.  The  third site is located on Orowoc
Creek in South Brentwood, Town of Islip.  Baseline data has been collected
at the Carlls River sites to establish  pre-control pollutant levels.  Sam-
pling at the Orowoc Creek site will  begin in  the spring.

The five remaining sites are all  recharge basins draining various land uses
and will be monitored by the U.S. Geological  Survey.  At  all sites there will
be monitoring of the inflow pipe, precipitation and a water-table well to
measure water-level changes and the  quality of  percolating runoff.  In one
basin there is no existing vegetal cover on the basin floor.  In three basins
no maintenance is carried out.  The  fifth basin has an impervious liner and,
therefore,  contains standing water at all times.

Using the data generated at the nine control  sites, the regional effective-
ness of the various control schemes  will  be evaluated by  means of the dynamic
mathematical models which were developed during the initial 208 study.

Using information derived from the evaluation phase, and  land-use information
from the 208 program, suggested stormwater runoff control procedures will be
developed for use by local agencies.  The procedures will incorporate the
most cost-effective structural and non-structural controls for the area.
They will be developed as a regional  approach to urban runoff control and
will have implementation geared to various localities on  Long Island and to
similar areas-of the country elsewhere  with specific instructions for manage-
ment, operation and maintenance of the  proposed systems.  Requirements for
implementation will also be included.   The legislative, institutional, fiscal,
and administration needs will  be addressed.
The Bayville site (figure 3), which is located along Perry Avenue between
Bayville Avenue and Creek Road, is in part situated on a steep grade which
is topographically representative of the north shore of Long Island.  The
land use in this drainage basin is essentially all medium density residential,
consisting primarily of single family dwellings on 60' x 100* plots, which
Is typical of development in Nassau County.  Automatic sampling and flow
measuring devices will be used for sample collection and flow measurement
at each of the three sampling points with the equipment located either in the
catch basin or overflow leaching pool structures.  Bacteriological samples
will be collected manually.  Precipitation is measured by a recording gauge,
installed on the roof of the Bayville Village Hall.  Unqua Pond, (Figure 4)
is located between Sunrise Highway and (derrick Road, adjacent to Marjorie
Post Park.  The drainage area contiguous to Unqua Pond 1s gently sloped and
topographically representative of the south shore of Long Island.  The land
use in this drainage basin is primarily medium density residential, but the
pond also receives runoff from Sunrise Highway, which Is a major east-west
thoroughfare, from a commercial shopping center and from the adjacent park
land.  Most of the stormwater discharge in this basin is diverted into
Unqua Pond and subsequently into South Oyster Bay.  Portions of South Oyster
Bay adjacent to the shoreline are presently closed to shellfishing, primarily
due to the bacteria loadings from stonnwater runoff.  Although there are a
number of ponds located along the south shore of Nassau County, Unqua was
selected for three reasons:  (1) relatively deep (3 to 5 ft) as compared to
most ponds, which are shallow (1 to 3 ft), (2) only one direct discharge
into the pond in addition to the primary stream inflow, (3) easy accessibility
to the Inflow and outflow sampling locations.  Essentially all sampling will
be conducted manually since the pond system ts unsecured and subject to
vandalism.  Automatic samplers may be used once on site, but bacteriological
samples must be collected manually.  Precipitation Is measured by a recording
gauge set up on the roof of the Marjorie Post Park Administration building,
located at the southern end of the drainage area.

Suffolk County Department of Health Services is studying three surface water
Sites, as follows:  Two sites are located on the Carlls River and are being used
to test the effectiveness of street sweeping.  The sweeping is being conducted
at site (1) Centra) Avenue, which has a drainage area of approximately 73 acres
Medium-density residential land use.  Streamflow gauging and water quality sam-
pling are carried out at a location in the stream channel downstream of the dis-
charge points of the two 48" diameter and one 24" diameter storm sewers.

Site (2), located on the west branch of the Carlls River, and a few thousand
feet north of Belmont Lake, will be used as a control on the street sweeping
evaluation at Central Avenue.  The site has a 48" diameter storm sewer col-
lecting runoff from a drainage area of approximately 64 acres of medium density
residential land use along Westview Avenue and West 24th Street.  Flow measure-
ment and water quality sampling are done at the pipe discharge, and in the stream
channel upstream and  downstream from the pipe.   Precipitation  is measured by  a
recording gage  located at  Belmont  Park Headquarters  and by manual gages set  up
at  the  sites by  sampling crews.
                                     G4-14
                                                                                                                                    G.4-15

-------
     "f-
     0,v ri«V. -'.-I '  .,
=«h   q*«S--'%Ji^s«5C
                                                    DRAINAGE AREA BOUNDAUY.
                                 i- 1 'Vj^J'- \y- ^-f"-  * ' ^^^^ t ' 3 *^^_ ^^ «rry to*"- ••  r  r^ b'X X.  •     ?
                                 i^y^^S^^^
Site (3)  Is at a trapezoidal  shaped recharge basin just  to the north of the
Southern  State Parkway in South Brentwood, Islip town, located on the service
road to the parkway.  The basin is approximately 450'  long and 300' wide at
its longest and widest points.  There is a storm drain draining a small
residential area that discharges  into the east side of the basin, roughly
200' downstream from the stream influent point at the northern end of the
basin.  A low (8"-10" high) concrete wall at the end of  the 10' long concrete
apron to  the storm drain, which has been in place for at least 15 years,
acts as a working, effective  energy disslpator.  The basin and stream channel
upstream  are heavily overgrown with wetlands vegetation  and, hence, provide
an effective site for wetlands treatment.  Upstream of the recharge basin,
the channel is dry for much of the year and resembles  the conditions predicted
in the  Suffolk County Flow Augmentation Heeds Study (FANS) for streams with-
out augmentation.

The parameters analyzed in samples from the above sites  include:  TKN, NH3-N,
HOz-N,  TOC, COD, TSS, Chloride, BOD,. Total Conforms,  Fecal Conforms, Fecal
Strep,  lead, chromium, cadimiurn,  zinc, copper. Iron, and mangenese.
                                                                                                         The five recharge basins  being monitored by U.S.G.S. are as follows:
                                                                                                         site shown in Figure 6):
                                                                   (Sample
        T.N-I.I.XE STORAGE  SYSTEM
             ["PERRY AVE.  DAYVTI,LE J
                                                                                                                Laurel Hollow is.located at the intersection of Cove Road and Moore's
                                                                                                                Hill Road in Laurel  Hollow, N.Y;,  This basin drains a 100-acre area
                                                                                                                of recently-constructed, medium-density housing.  Some construction
                                                                                                                was still going on  in  1979.  The basin is  three acres in area and
                                                                                                                trapezoidal In shape.  The basin floor is  approximately 14 feet below
                                                                                                                land surface.

                                                                                                                The Plain view basin,  also known as Hew York State Department of
                                                                                                                Transportation Highway Basin 66, Is located at the Intersection of
                                                                                                                Mashington Avenue and  Executive Drive in PTainvlew, N.Y.  This
                                                                                                                basin receives runoff  from the Long Island Expressway, its service
                                                                                                                road, and a small number of local  streets  - a total of 7,000 feet
                                                                                                                of roads, or approximately eight acres of  impervious surface area.
                                                                                                                The basin is approximately two acres in size and square In shape.
                                                                                                                The basin floor is  40  feet below land surface.

                                                                                                                The Syosset stormwater recharge basin is located at Cary Street in
                                                                                                                Syosset, N.Y.  This  basin Is also  known as Nassau County Storm Water
                                                                                                                Basin 377.  This basin drains a 28.2-acre  high-density residential
                                                                                                                area.  Housing construction in this area was completed in 1957.  The
                                                                                                                basin Itself is one  acre In size and triangular In shape; its bottom
                                                                                                                is 14 feet below land  surface.

                                                                                                                The Huntington stormwater recharge basin is located at Halt Whitman
                                                                                                                Shopping Center on  Route 110 at South Huntington, N.Y.  This basin
                                              64-16
                                                                                                                                           G4-17

-------
       drains the north half of the  shopping center which includes approxi-
       mately 39 acres of paved parking and roof area.  This basin is clogged,
       but storm water can exfiltrate  the walls above the clogging layer.
       The number of shopping center basins is small (less than 50), but
       the large volume of man-made  organic compounds that enter these
       basins may have a disproportionately large Impact on the quality
       of ground water.

       The Centereach stonnwater recharge basin is located near the north-
       west corner of the intersection of Oak Street and Middle Country Road
       (N.V. Route 25) in Centereach.  This basin drains Middle Country Road
       and the commercial areas on both sides of the road.  This basin is
       different from the other four in that it has a liner, which causes
       it to retain a pre-determined volume of water.  Excess stonnwater is
       recharged to the ground water via an overflow pipe connected to a
       leaching field.

In all five basins, flow measurement data, water-quality samples and micro-
biological samples will be collected at the inflow pipes.  A watertable  well
will be placed in each basin to monitor water-level changes and the quality
of percolating runoff.  A rain gage  will be placed in each basin to record
rainfall  input.

Equipment
Equipment
               8 of Pieces  Manufacturer
I.  NASSAU COUNTY DEPARTMENT OF HEALTH
Automatic Re-
cording Rain
gauge

Manual Rain
Guage (dip-
stick type)
Flow Meter
Portable
Flow Meter

Manual Flow
Gauge-Staff
Gauges

Automatic
Water
Sampler
2       Weather Measure



2       Bel fort




3       Marsh-McBirney


1       Marsh-HcBirney


2



3       I SCO
                           Model  i
P501-1
                                         Site
Bayville,
Massapequa
U.S. Weather  Bayville,
Bureau- Spec-  Massapequa
ification
#4502301
VMFM 265


201






2100
Bayville,
Massapequa

Bayville,
Massapequa

Massapequa
                                          Bayville,
                                          Massapequa
                                     G4-18
                                                                           Equipment     t of Pieces  Manufacturer        Model  t

                                                                           11.  SUFFOLK COUNTY-DEPARTMENT OF HEALTH SERVICES

                                                                           Flow Meter         3       Harsh-HcBirney      VMFS 265
Conductivity
Meter
Cone Sample
Splitter
pll Meter
or
pll Meter
D. 0. Meter
Temperature
Standard 8" Dia-
meter Manual
Rain Gage*
Tipping
Bucket Rain
Gage*
1
1
1

1
1
1
1
III. U. S. GEOLOGICAL
Automatic
Sampler
Velocity
Modified
l;low Meter
Minigraph
Event
Recorder
Tipping Bucket
Rain Gage
w/Recorder
Atmospheric
Deposition
Water-Level
Recorder
4
5
4
4
2
4
Horizon Ecology
Company
Leonard Hold &
Die
Horizon Ecology
Company

Leeds & Northrup
Yellow Springs
Instruments
Science Associates
Weather Measure
Corporation
SURVEY
Manning
March-McBirney
Esterline Angus
Leupold & Stevens
N-Con
Leupold & Stevens
1484-10
-
5995

7417-L2
57


S-6000
250
none
7012
none
Type F
                                                                                                            Site



                                                                                                            CarlIs River-Energy
                                                                                                            Dissipation

                                                                                                            Sampling Vehicle


                                                                                                            Sampling Vehicle


                                                                                                            Sampling Vehicle




                                                                                                            Sampling Vehicle

                                                                                                            Carl Is River-Energy
                                                                                                            Dissipation

                                                                                                            Level area at
                                                                                                            Sampling site


                                                                                                            Belmont Lake State
                                                                                                            Park Headquarters
Five basins,  four
instrumented  at any
given time

Five basins,  four
instrumented  at any
given time

Five basins,  four
instrumented  at any
given time

On-site at Hunting-
ton Laurel Hollow,
Plainview Syosset -
rear of USGS  off.

Huntington Basin
Platnview Health
Center

Five basins,  four
Instrumented  at any
given time
                                                                                                                                 64-19

-------
Controls

The in-line storage system In Bayville,  Hew  York,  consists of a series of
leaching-type catch basins and leaching  pools  connected with perforated
reinforced concrete pipe.  The catch basins  are  located strategically along
Perry Avenue for collection of runoff from storm event.  Any overflow from
the basins enter perforated pipes  (v/here some  leaching also occurs) that
allow the stormwater to flow from  one leaching pool to the next as each fills.
If the storm runoff Is of sufficient volume  to fill all the leaching catch
basins and pools, then the excess  volume will  flow into Hill Neck Creek.
Figure 7 shows cross sectional views of  a typical  leaching pool, leaching-
type catch basin, and perforated pipe.  The  design capacity of this stream
will theoretically retain a one-in./24-hour  storm  before there Is any over-
flow and discharge to the marine waters. This design  is Intended to capture
and retain the stormwater generated from approximately 851 of the rainfall
events 1n the Long Island area.

Unqua Pond Is located In the Village of  Massapequa between Sunrise Highway
and derrick Road adjacent to Marjorle Post Park.  The  pond Is relatively
deep (3 to 5 ft) compared to most  ponds  on Long  Island, which are shallow
(1 to 3 ft)  Unqua Pond has one stream Influent  and effluent, but it also
receives urban runoff from a small stormwater  drainage system discharge.
Natural sedimentation on detention are the processes that are being evaluated
by this control measure.  The site Is currently  a  control measure as It exists,
and the only changes that will occur are the installation of monitoring equip-
ment.  Ducks and geese located on  and around the pond  contribute significant
quantities of nutrients, biochemical oxygen  demand, and bacteria to the pond.
Feeding of the ducks and geese by  people in  the  area tends to increase their
population around the pond, thus contributing  to more  pollution.

For the Carlls River street cleaning site, existing Elgin Pelican street
cleaning equipment will be used.  This equipment will  be operated In accord-
ance with a predetermined operation schedule.  At  present, this area has a
typical street cleaning frequency  of five times  per year.  During the HURP
study, the same mode of operation  and piece  of equipment should be used to
control the number of variables to be considered when evaluating the results
of street cleaning.  Frequency of  sweeping and antecedent rain will be the
only major variables.

The dry stream channel energy dissipation/wetlands treatment at Orowoc Creek
involves a recharge basin through  which  the  stream channel passes.  Up stream
of the recharge basin, the channel is dry for  much of  the year, which would
resemble the conditions predicted  in the Suffolk County Flow Augmentation
Heeds Study for several of the streams without augmentation.  In addition,
there 1s a storm drain which discharges  into the basin from a small residen-
tial area.  The stream channel and the recharge  basin are heavily overgrown,
the latter with typical wetlands species.

Suffolk County Department of Health Services will  be assessing the stormwater
runoff treatment benefits that may result from the drying up of portions
of streams due to the effect of sewering. The department is in the process of
establishing a monitoring station  at the basin influent to evaluate the treat-
ment provided by the dry stream channel; a monitoring  station at the storm
                                    G4-20
drain discharge to the basin, to sample runoff from the small residential
area; and a sampling point at the basin effluent to evaluate the treatment
provided by the wetlands vegetation and from recharge in the basin.

Because of the existence of heavy vegetation in the channel up stream and
also in the recharge basin, It is anticipated that there will be several
storms for which there may not be measurable flow at the basin's Influent or
effluent points.

The originally proposed energy dissipation construction at the Hestvlew
Avenue site, on the Carll's River, has been dropped from the study for the
following reasons:

    the low bid for constructing the facility was $41,000, which was
    approximately $20,000 more than the consultant's estimate.

    although the SCDHS' field crew had Identified 40 to 50 potential sites
    where energy dissipation could be Implemented, the total contributory
    drainage area to these sites has been found to be less significant than
    envisioned prior to the site Inspections.

    energy dissipation/wetlands treatment will be better evaluated at the
    storm drain discharge to the Orowoc Creek Site, where an existing energy
    disslpator and wetland has been operating for many years.

The Westvlew Avenue site is being retained In the monitoring program to facil-
itate evaluation of the Impact of varying street cleaning practices at Central
Avenue.  Both Carll's River sites will be sampled during the same storm events.
                                                                                                                                     G1-21

-------
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                                                    U.8.G.S. GAGE
                                                                                      SOUTHWEST SEWER
                                                                                      DISTRICT BOUNOART
             _.  ,..     .  ...»
 I'l.ATX SKDTMKN'T/rrrON^.VATliriAI. IMPOUNDMENT SYSTEM
        TliMU rONJOIASSAPEQUA   G4-22
                                                                      G4-23

-------
    TE:
      faf^wirigsectTW^s Txcerprecrfrd^^ie  nS^'.Is^ffd
Waste Treatment  Management  Plan,  published in  1978.
2.2 GROUND WATER POLLUTION SOURCES
2.2.1  Background
      An evaluation of ground water pollution sources is one of the products
of the Long  Island 208 areawide waste management study. A full report,
presented to the  208 Technical Advisory Committee by Geraghty & Miller,
Inc. in September 1977, describes eighteen different activities which have or
may impair ground water quality in the study area. This  section has been
prepared to provide easy access to the salient facts contained  in the longer,
more  technical version. The potential  impact of  the various contamination
sources discussed  may be subject to reassessment  at a later date as more data
are made available, or as legal requirements initiate a change  in practices.
      Although the ground water contamination  contribution of several of
the sources described may not appear to be significant, it should be borne in
mind  that the quality  of the regional ground water  supply is susceptible to
the adverse  effects of the sum  total  of man's activities on  land. This under-
standing  is particularly crucial to Long Island where activities are diverse, and
where a water supply  alternative  to ground water is not readily or economi-
cally available.
      There are many  sources and causes of ground  water  contamination in
the 208 area.  Basically, they can be divided into four categories (Table 2-1).
The first two categories represent discharges of contaminants that are derived
from  solid and liquid wastes.  The third category concerns discharges of con-
taminants that are not wastes, and the fourth category  lists'lhose causes of
ground water contamination that are not discharges at all.
      The  variety and type  of management options  available  for each
category  differ.  For example,  some Category I sources  may  require a dis-
charge permit whereas others can be controlled by restrictions on land use.
Sources under Category II may require satisfaction of specified construction
standards,  such  as the lining of landfills  and the  installation  of  leachate
collection systems. Guidelines  and manuals (e.g., tons/land-mile  limits on
highway  deicing salts) may be the only type of management option available
for Category III.  Special regulatory  controls are  available  for the causes of
ground water contamination listed under  Category  IV.  An example  is the
current system of ground water diversion applications and hearings employed
to minimize salt  water encroachment. Another  is the  licensing of drilling
contractors in order to upgrade water well construction practices.

2.2.2  Domestic On-Site Waste Disposal Systems
      Cesspools, septic  tanks and leaching fields are a source of ground water
contamination on Long Island that has been of great concern to many investi-
gators and regulatory agencies. "The  Final Report of the Long Island Ground
Water  Pollution Study" stated that  800,000 persons in Nassau and  950,000
persons in Suffolk reside in unsewered areas (Nassau-Suffolk Research Task
Group, 1969). In  addition,  facilities serving 24,000 people residing in Nassau

                                G4-24
                                                                                                           Table 2-1

                                                                                  CLASSIFICATION OF SOURCES AND CAUSES OF GROUND WATER
                                                                              CONTAMINATION USED IN DETERMINING LEVEL AND TYPE OF CONTROL
                                                                                               Category II
                                                                                             Systems, facilities,
                                                                                             or sources not
                                                                                             specifically designed
                                                                                             to discharge wastes
                                                                                             or waste waters to the
                                                                                             land and ground
                                                                                             waters.

                                                                                             Sanitary sewers
  Category III
Systems, facilities,
or sources which
may discharge or
cause a discharge of
contaminants that are
not wastes to the land
and ground waters.

Highway deicing and
salt storage
                                                                                             Landfills


                                                                                             Animal wastes


                                                                                             Cemeteries
Fertilizers and
pesticides
Product storage
tanks and pipelines

Spills and incidental
discharges

Sand and gravel mining
  Category IV .
Causes of ground
water contamin-
ation which are
not discharges.
Airborne
pollution
Water well con-
struction and
abandonment

Salt water
intrustion
   Category I
Systems, facilities
or sources designed
to discharge waste
or waste waters to
the land and ground
waters.
Domestic on-site
waste disposal
systems

Sewage treatment
plant effluent
Industrial waste
discharges

Storm water basin
recharge

Incinerator quench
water

Diffusion wells

Scavenger waste
disposal
                                                                         Sewer District No.  2 were reported as not being hooked up to the sewer
                                                                         system. Other reports give different estimates for the number of cesspools
                                                                         and  septic  tanks  in Nassau  County  (Nassau  Environmental  Management
                                                                         Council, 1974 and Padar, 1968). The U.S. Geological Survey has estimated
                                                                         that in 1966, 120 million gallons per day  of sewage were returned to the
                                                                         ground through cesspools and septic tanks on Long Island (Parker, 1967). A
                                                                         more recent paper from the Nassau County  Department  of  Health  reports
                                                                         that 150,000 cesspools in Nassau alone discharge  60 million gallons per day
                                                                         (Smith, 1975).
                                                                               In on-site disposal systems, bacterial action  digests the solid materials,
                                                                         and  the liquid effluent is discharged to the ground. In theory, filtration by
                                                                         earth materials provides additional  treatment so  that the liquid, when  it
                                                                         arrives  at the water table,  is relatively clean. However,  many constituents
                                                                         carried by the effluent are introduced to the ground water  system. Those
                                                                         which present the greatest threat to ground water quality  are excessive con-
                                                                         centrations  of nitrate, organic chemicals, detergent, metals,  bacteria and
                                                                         viruses.  Other  constituents-previously ignored,   but now recognized  as a

                                                                                                            G4-25
                                                                                                                                                                59

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      threat-arc  halogenated hydrocarbons.  Compounds  such  as chloroform,
      carbon tetrachloride, trichloroethylene,  and  others are in  common use in
      industry as degreasers and solvents or are incorporated in plastic products. It
      has only recently been recognized that these and similar compounds regularly
      occur in discharges  from households. Many products common in the home,
      such as fabric and rug cleaners, workshop cleaners and solvents, and solutions
      to clean  pipes  find their way  into on-site  disposal  systems. Septic  tank
      cleaners are composed  almost entirely of active ingredients which are fre-
      quently  halogenated hydrocarbons. For example,  one common cesspool
      cleaner contains more than 99 percent trichloroethylene. One gallon of this
      compound  could  raise  the trichloroethylene concentrations  of 29 million
      gallons of water to the State recommended maximum of  0.05 parts per
      million.
           Cesspools  and  septic tanks are viewed by regulatory agencies as low-cost
      systems  which  eliminate surface discharges of raw sewage.  There are  areas
      where low  housing density and favorable soil conditions make such systems
      satisfactory  alternatives to  expensive  trunk sewers and treatment plants.
      However, government agencies have been leaning more and more toward the
                                                 latter  in recent years. Sewer districts have been delineated in both counties
                                                 and plans for  construction are well underway. Figure 2—14 is a nitrogen-
                                                 loading map, showing the areas in which more than 40 pounds of nitrogen are
                                                 added annually to each acre by  cesspools and septic tanks (Weston, July
                                                 1976). This  map  does not include the  nitrogen loading that  results from
                                                 agricultural and domestic fertilizer applications.

                                                 2.2.3 Sewage Treatment Plant Effluent
                                                      At present,  sewage treatment plant effluent is only a minor threat to
                                                 ground water quality in the bi-county area, as most of  the effluent is dis-
                                                 charged directly to the sea.  According to a study made by Weston in 1976, 23
                                                 plants in Nassau County discharge an average of 105.63 million gallons per
                                                 day,  and in Suffolk County 101 plants  have an average discharge of 14.26
                                                 million gallons per day (Weston, July 1976). These are the total flows of the
                                                 NPDES and SPDES permitted sewage treatment systems and are believed to
                                                 include all plants  in both counties. Figure 2—15 shows the locations of plants
                                                 that discharge to the ground.
                                                       In Nassau County, only one percent of the total daily flow of treated
  o
                                                                                                                                   LEGEND

                                                                                                                    GREATER THAN 40 LBS OF NITROGEN/ACRE/YEAR
                                                                                                                   ! FROM CESSPOOLS AND SEPTIC TANKS
                         G4-26
FIGURE 2-14    Areas of Major Concentrations of On-Site Domestic Waste Disposal Systems.
                                                                           G4-27
GO

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effluent (1.2 million gallons per day) and in Suffolk County 50 percent of the
total daily flow of treated effluent (7.39 million gallons per day) are  dis-
charged to the ground. Thus, a total of 8.59 million gallons per day enters the
ground compared to about 800 million gallons per day total recharge of fresh
water from precipitation in the bi-county area. Although small, this discharge
of effluent to the ground may have a significant effect when concentrated at
a few sites.  In Nassau County, effluent is discharged at five sites: Meadow-
brook Hospital (0.77 million gallons per day), Farmingdale Sanitorium (0.07
million gallons per day), C. W. Post College  (0.12 million gallons per day),
New York Institute of Technology  (0.003  million gallons per  day), and
Grumman Aerospace Corp. (0.25 million gallons per day).
     In Suffolk County,  the 85 facilities which discharge treated  sewage
effluent to the ground are predominantly small residential facilities and some
special health and elderly care facilities (Weston, July 1976). Suffolk County
is  undergoing rapid development and many  small sewage treatment plants
are being installed to serve areas of 100 or more homes. In developments of
less than 100 homes where no sewer system is available, builders are required
to install sewers, which will be placed Into service after future construction of
a nearby interceptor. These homes are permitted to temporarily discharge to
cesspools and septic tanks (Pirn, 1977).
     Some  systems receive domestic wastes exclusively; others accept,some
industrial  wastes.   Regulatory  authorities  make every  effort  to  exclude
constituents harmful  to the  treatment  plant  process  or employees,  but
incidental discharges  are  not easily controlled.  Some chemicals,  such as
solvents, do not appear to be harmful over  the short term, but may damage
either the plant or sewer system over a long period of time.
     According to a NYSDEC law, effective  secondary treatment is the
minimum  required before effluent can be discharged  to surface water.
Although this law does not apply to plants discharging to the ground, second-
ary treatment  also is common.  Only  Farmingdale Sanitorium  in Nassau
discharges primary  treated effluent to the  ground (0.07 million gallons per
day). In Suffolk, of the 85 plants discharging to the ground, only six do not
provide at  least secondary treatment. Denitrification of sewage effluent is
now required of all new sewage treatment plants which discharge to ground
water in Suffolk County.
     A recently released report by  Roy Gilbert  of  the SCDEC states that
                                            •          •      .      • •  •
                                                 • :.o       S'Uf F  M. K
                                                                                 a 11 a ii I i n    n r n n n
                                                                                                                              LEGEND

                                                                                                                          DOMESTIC WASTE TREATMENT PLANT
                                      FIGURE 2-15    Domestic Waste Treatment Plants Discharging to Ground Water,  1978

                          G4-28       ,                                                                     G4-29
                                                                                                                                                            61

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        a number of organic compounds present  in treated sewage are refractory
        products (not affected by the treatment process) of the biological treatment
        of the plant, or new compounds formed during chlorination (Gilbert, 1977).
        It is possible that  these products may move  through  the unsaturated soil
        to contaminate ground  water in places where  the  effluent  is discharged to
        the ground.
             The New York State Environmental Conservation Law of 1967 em-
        powers agencies to regulate sewage treatment  plants. This law provides for
        the classification of state ground water and establishment of quality standards.
        Violators are assessed penalties under the  Federal  Water Pollution Control
        Act  (PL 92-500). The  NPDES program was established in 1973 and the
        SPOES  program in January 1975; the SCOEC and the NCDH derive their
        enforcement powers from these.

        2.2.4 Sanitary Sewers
             Approximately 120 million gallons per day of raw sewage flow through
        thousands of miles of sewers  in  the bi-county  area.  The  flow in  Nassau
        averages 105.63 million gallons per day and in Suffolk, 14.26 million gallons
per day (Weston, July 1976). Figure 2—16 shows the locations of sewered
areas. Sewers frequently leak, and depending upon the type of sewer and its
altitude relative to the water table, ground water can infiltrate or sewage can
exfiltrate.  The contamination that takes place in the latter case  is normal
domestic sewage, plus those constituents in industrial effluent discharged to
sewers.
      Since the enactment of  the SPDES permit program, the direct discharge
of industrial wastes to septic systems has been severely curtailed. Restrictions
on industrial discharges to  sewers are much less stringent than those covering
such discharges to septic systems. Concern over the constituents in industrial
effluent is primarily due to their effects on the sewer system, the treatment
plant processes, and  treatment plant personnel—not their effects on ground
water.
      Permissible maximum infiltration rates are usually written into sewer
specifications and commonly vary from 200 to 500 gallons per day per mile
per inch of pipe diameter.  Where ground water pollution is of concern, exfil-
tration rates are also specified. In Suffolk County's Southwest Sewer District,
for example, 200 gallons per  day per mile per inch of pipe diameter has been
                                                                              long    i s I a ii il     s o ii n il
              r~
           JVV«
V~n*i,
    city  nI  A.,i;-4|
 »«* y°|K Jll-f  M^SSAU
                                                                                     a 11 a n t i c    ocean
                                                                                                                                          LEGEND

                                                                                                                                           SEWERED AREA
                                                              FIGURE 2-16    Presently Sewered Areas, 1978
  62
                            G4-30
                             G4-31

-------
specified as the maximum rate for exfiltration. Projections from tests carried
out on existing sewer lines show that leakage has been considerably less than
this figure (Graner, 1977).
     The potential volume of exfiltration is small when compared  to  the
nearly  100  percent discharge that occurs from cesspools and septic tanks.
However, exfiltration may increase over the years as loading produces breaks
in the pipes and joints, and as chemical action deteriorates the joints. Exfiltra-
tion  may also  increase if  the ground water  level was originally above  the
sewer, but has declined to a point below the sewer.
     With present materials and construction  techniques, a 50 year sewer life
is used as a minimum design estimate. However, a 100 year life may be a
more  reasonable  estimate  (Graner,  1977). Some of  the older  systems In
Nassau County are  receiving  large volumes of ground water (Long  Beach,
Glen Cove,  Oyster Bay and Freeport) (Cameron, 1977). If these systems are
infiltrating  additional water where the pipes are below the water table, it is
reasonable to assume they are also exfiltrating additional sewage where  the
pipes are above the water table. Similar problems may be occurring in older
Suffolk  systems,  such  as  Port  Jefferson,  Huntington,  Northport  and
Patchogue.
      Except for monitoring volumes, and to some extent, chemical quality
of incoming  waste  at sewage treatment plants, little control is exerted on
sewers once  the  construction  specifications are satisfied. Severe problems
involving exfiltration, infiltration or clogging are remedied where they inter-
fere with the operation of the system or cause a public nuisance.
2.2.5 Industrial Waste Discharge
     Industrial development and zoning are extensive on Long Island.  In
1972, five percent of the Nassau-Suffolk area was zoned for industry. Most
of this acreage is  inland and includes such heavily industrialized areas  as
Syosset,  Hicksville,  Bethpage-Plainview, Melville-Farmingdale,  Hauppauge
and  Deer  Park.  Except for a small  part of the Melville-Farmingdale area,
all of these zones and a number of smaller ones in Suffolk County are located
in the recharge area  of the Magothy  aquifer. Areas of known industrial dis-
charge to the ground  are shown on Figure 2-17.
     Although there are discrepancies in the number of Industries  reported
to have  permitted  discharges, the nature and volume of NPDES and SPDES
discharges are documented  in a  1976 report prepared by Roy F. Weston
                                                                               allantic    ocean
                                                                                                                                      LEGEND

                                                                                                                                     • INDUSTRIAL SITE
                         G4-32
                                            FIGURE 2-17    Major Industrial Sites Discharging to Ground Water*  1978

                                                                                                                 G4-33
                                                                                                                                                           63

-------
       (Weston. July  1976). According to the report, in Nassau 1.2 million gallons
       per day of waste water are  discharged by industry. About 800.000 gallons
       per day  of this amount  are discharged to the ground. In Suffolk County,
       88  industries  discharge  a total of  1,325.000 gallons per day,  of which
       1,278,900 gallons per  day  are discharged  to the ground.  Thus,  in the bi-
       county  area,  about  2.1  million gallons per day  of industrial wastes  are
       discharged to the ground in a few industrialized areas.
             There are also commercial and industrial discharges in both counties,
       not  included  in  the permitted  inventory.  These include  car washes, coin-
       operated laundries and industries discharging waste water with constituents
       not covered by permitting regulations.
             In an attempt to control industrial waste discharges, Nassau County
       has  recently  instituted  a program to inventory  all  industries, according to
       the  nature of  and receiving body  for their discharges. The inventory  has
       revealed a  number of industries that are discharging untreated liquid wastes
       to cesspools (Burger, 1977). Abatement actions have been initiated in these
       cases.  Suffolk County  has  been conducting industrial surveys for several
       years.
             In Suffolk County, a list of  car washes and coin-operated laundries
        has been compiled. Ten car  washes  presently  discharge to ground water;
        these predate the State  DEC regulation requiring closed systems. There are
        135 coin-operated laundries discharging to  the ground water; two of these
        ha.-a once-through waste treatment  and four others have partial  treatment
        (Gilbert,  1977). Twenty-five percent of Suffolk's coin-operated laundries
        discharge to sewers and  require no pre-treatment (Pirn, 1972). Forty-five of
        the laundries  discharging to the ground are in the Southwest Sewer District
        and will be sewered  in the future.  Nearly 500,000 gallons per day discharges
        to ground water from 75 of  these laundries.
             In Nassau County, permitted discharges to the ground amount to about
        800.000 gallons per day. Fourteen metal processing firms  discharge 726.000
        gallons per day, which is 90 percent of the  total. The bottling industry pro-
        duces an additional  32,000 gallons  per day, and the food industry, 24,000
        gallons per day. Very small discharges are  from metal powder mixing  and
        paper processing industries (Weston, July 1977).
             In Suffolk County, 1,278,900 gallons per  day  of industrial  wastes are
        discharged to  the ground. This includes 470,989 gallons per day from metal
        processing,  356,813 gallons per day  from commercial laundries,  164,978
        gallons per day from dairies and 152,18^'gallons per day from bakeries.
             Prior to the passage of the New York State Environmental Conservation
        Law in 1967, there was no effective  law limiting the types of waste water dis-
        charged to the land surface. With the enactment of the NPDES and subsequent
        enactment of  the SPDES,  a  NYSDEC permit is required for non-sewered
        industrial effluent discharges.  The  industry must produce  treated effluent
        which meets state water standards.  Compliance is monitored by the NCDH
        and the SCDEC. These agencies also enforce  sludge disposal rules.
2.2.6 Storm Water Basins
     Investigators have determined, that on Long Island approximately half
the annual precipitation  finds  its way to the ground  water reservoir as
recharge. This averages roughly one  million gallons per day per square mile
in a 760 square mile recharge area.  As the western part  of the region has
become increasingly  urbanized, however,  permeable  soil areas have  been
replaced by impermeable roofs and paved areas. The water cannot  seep into
these surfaces, so it accumulates and runs off.
     As a water  conservation  alternative to offset reductions in  ground
water recharge and to eliminate the need for expensive trunk sewers leading
to the  sea,  a system of small storm sewers draining to unlined recharge basins
was implemented in Nassau County  in 1935. At the present time, there are
more than  2,000 basins on Long Island, the locations of which are shown on
Figure  2—18 (Seaburn,  1973). The basins range from less  than  one to more
than 30 acres in size but most are about one acre. They average ten to twenty
feet in  depth.
     Recharge basins have been considered to  be highly beneficial to the
overall water conservation program on  Long Island, since they account for
approximately  twenty  percent  of all recharge  to  the underlying aquifers
(Aronson, 1974). Although the basins restore potentially lost recharge, they
are also sources of contamination.  Inflow into the basins is a combination of
precipitation plus constituents that are dissolved and suspended by  the water
as it runs over the ground. Typical  sources of contaminants are fertilizers,
pesticides, deicing sa>ts, organic debris, grease and road oil, rubber, asphaltic
materials, hydrocarbons, animal feces and food wastes. Many of the contam-
inants  are not biodegradable and persist in ground water.
     As part  of the 208 investigation, a number of studies were conducted
which  have bearing  on  the amount  and  types of pollutants  that may be
entering the ground water system via storm water  basins. The Weston non-
point source analysts  included sampling  runoff from small  drainage areas and
correlation of the runoff quantity  and quality with the prevailing land uses.
The data and analyses indicated that annual toads of pollutants from non-
point  sources can  be as large  as loadings from  traditional point  sources
(Weston, April 1977).
     In their program of storm water runoff and ground water sampling at
two recharge basins along the Long Island Expressway, the SCDEC detected
significant  intermittent concentrations  of  selected heavy  metals (e.g., zinc
and lead) and total organic carbon (TOC) in discrete samples of storm water
runoff during  the sampled storm events. Chloride and zinc were observed in
elevated concentrations  in the ground  water samples obtained from  wells
located in  the two recharge basins receiving storm runoff  from the Express-
way. The SCDEC concluded that further investigation is obviously necessary
to determine if runoff quality from  the Long Island Expressway is compar-
able to the often reported major waste load attributed to heavy  metals in
runoff  (Minei.1977).
C4
                                 G4-34
                                  G4-35

-------

•           t    i-
«*M.ti 1C    (I / '•rtfK"^=^"-V*
HI x
s^v^ttrr->dLJ.QH
                                                                                                 j.        --   •!•-••--;j*~-JUl-•/••"/" <*-•/.-.;*:::
                                                                                                 !  H.A1.V SKnlMEXTATIOM^SATUIML IHI'OUXUMEiVT
                                                                                                             ^JNtjUA j-O.VI) IMASSAPEQUA
                                                                                                                                     G4-37
   PI.ATX 5KnlMENTATTO.^-gfATURAL  IHPOUNDMEN'T  SYSTEM

                        POMDVMASSAPEQl/A

-------

   MUNICIPALITIES  and C.D.P.'s. .

  (Census Designated Places) -1S80
                  NASSAU COUNTY

                  SUFFOLK COUNTY

                   ***• •L**"^ kit Mini
•X Cull* &. (C«MvU MM.)

H. Ctfll*

ii. OMMDC
                 Figure 2 - Project.Area and Sampling Sites
I    i  "*f~"\ut'Sif"'"""  V-»™~ *r7j'—""SI'-B.  J    >r      ^-   /  P*J*~

S=i5a3N5^*T f|: ^       V ,>"^
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L^^.*=   ^Sk^.vj'fe         •     __lr-=f
                                                   —~           	
    MUNICIPALITIES and C.D.P.'s. .

   (Census Designated Places] -1980
                   mr tlt»*
                  NASSAU COUNTY

                  SUFFOLK COUNTY
 •a! WMM'M ""' "'   '  5! •y«M«t'(c*rr'i«.}


 •4! CUlU &. (»M»i«r M*,)   «i. IkJtMUlM**

 •4. OmMteMk       «. ft	


                D •
                 Figure 2 - Project.Area and Sampling Sites	

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NATIONWIDE URBAN RUNOFF PROGRAM

 NEW YORK STATE DEPARTMENT OF
  ENVIRONMENTAL CONSERVATION

        LAKE GEORGE, NY

        REGION II, EPA
             •GS-1

-------
                              INTRODUCTION
     Lake George is located In the eastern Adirondack  Mountains of  New York  State
and the southeastern portion of the Adirondack State Park  not  far  from the Vermont
State border (Figure 1).  Sometimes called the Queen of  American Lakes,  its  clarity
is nearly unsurpassed In the United States.

     Lake George lies mostly within Warren and Washington  Counties; the  northern
tip of Lake George, at Ticonderoga, is within Essex  County.  Host of Lake George's
commerce Is located along the southwestern shores of the Lake, which are within
Warren County.  The commercial district is concentrated  mainly at  the southern
tip of the Lake at Lake George Village.

     The major use of the waters of Lake George has  been for recreation.   It also
provides a potable water supply for its peripheral inhabitants.   In order to
maintain the Integrity of the waters, the State has  designated  it  as a "Class
AA-Special* water body.  In addition, Title 17-1709  of the New York State (NYS)
Enviromental Conservation Law prohibits the discharge of sewage  into waters  of
the Lake.

     The population in Lake George is dominated by seasonal variations,  since
this lake is a popular resort area.  The year round  population in  Bo 1 ton and Lake
George Village, the two largest communities of south Lake  George,  is approximately
5000 persons.   In the summer, this increases about  tenfold to 50,000 persons.
New York State projections for these two communities show  the  populations increasing
to 6,000 permanent residents and 66,000 summer residents by the year 2000.

     The recreational-based economies of communities in  the Lake George  region
are heavily dependent upon maintaining a high level  of water quality in  the  Lake.
In recognition of the Lake as a unique resource, there has been a  strong, long-term
State and local commitment to protect and enhance the water quality of Lake  George.
This has resulted in a number of detailed studies of the Lake  and  in a long  history
of spirited public debate over the Lake's present and future quality.

     Although the water quality of Lake George has been studied  for over fifty years
most of the emphasis has been placed on the physical and chemical  nature of  the open
water.  Only in the last decade has the lake's watershed been  the  object of
scientific  investigations, and almost all of this work has been  in  determining the
water chemistry at the mouths of the ten or so major tributaries.
                                         65-
                                                                                                        FIGURE 1 - STATE  LOCUS AMD PROJECT AREA OF

                                                                                                                   LAKE GEORGE NURP
N
/
                                                                                                                            __
                                                                                                                      WARREN
                                                                                                                                                     SCALE  IN  MILES
                                                                                                                                        G5-3
                                                                                    J

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                          PHYSICAL INSCRIPTION
A.   Area
     Lake George is long and narrow; its major axis extends in a north,  northeasterly
     direction.  The Lake may be considered as two basins,  commonly referred to as
     North and South Lake George, respectively.  The South  Lake Is further divided
     into two basins, South and Central, on a raorphometric  and circulation basis;
     each contains a very deep section and several shallower areas.  The deep South  .
     basin is also called Caldwell Basin.

     Lake George has 4 lake surface which stands at 97 ra above sea.level and en-
     coiiipassess XI km.   The drainage basin surface area is 492 km.   The lake
     averages 18.3 m in  depth and varies in width from 1.6  kin to 4.8 km  along
     its 51.5 km length.

     Most of the drainage basin Is covered with shallow soil from glacial debris,
     with numerous outcroppings present.  The lake shore is irregular, steep and
     rocky, with the lake at a rather low level, amid elevations of considerable
     height,  cheating a  steep and fjord-like appearance. About 16 km of a total
     of 492 km  is developed urban land, concentrated in the towns of Lake George,
     Bo I ton,  Fort Ann, Hague, Queensbury, Dresdan, Putnam,  Ticonderoga,  and
     strip/shore developments along approximately half of the lake shoreline.
     (Figure 1)  The rest of the area is sparsely-populated, deciduously-forested
     land with numerous  conifers also present.
B.   Population
                                                                              in
     According to HeIliny (1974),  the population of the Lake George watershed
     1970 was 32,484. of which 16,138 resided in sewered areas.   The Town  and
     Village of Lake George accounted for 50.5< of  the total and  90.9* of  the
     sewered population in 1970.   However,  of the total watershed population
     of 32,484, only 17.2% or 5,575 were year-round residents.  Ferris et  al..
     (1980) estimated a slightly smaller population for the watershed (10,160).

C.   (Ira in aye

     Surface runoff into the lake  is greatly affected  by the physical characteristics
     of the basin, vegetation cover, areal  variations  and distribution of  precipitation,
     soil moisture arid groundwater, and development of the area by man.  The shallow
     soil cover, abrupt topography, steepness of slopes, and short travel  of runoff
     make storm runoff very rapid  and tumultuous.  The shape of the basin  is
     elongated and this, coupled with the steep topography, creates a large  number
     of streams with small drainage areas relative  to  the size of the lake.   Of
     the 80 streans flowing into the lake,  about one-fourth are Intermittent.
     The water volumes in the North and South basins are equal at 2.11 billion
     cubic meters (1,689,600 acre-ft) for each.  The average water retention time
     in the lake is 7.98 years.
                                                                                                 0.    Sewerage System

                                                                                                      The Village of Lake George is totally sewered with separate sewers and  Is
                                                                                                      served by a secondary sewage treatment plant utilizing trickling filters and
                                                                                                      sand beds.  Phosphorus is raaoved by passage of the sewage through the  sand
                                                                                                      beds whereupon the effluent is released as a subsurface discharge.

                                                                                                      The Village of BoIton Landing, the other major concentration of population
                                                                                                      on the South Lake, is about 75X sewered with a separated system.  Secondary
                                                                                                      treatment is provided by the same type of tricking filter and sand-bed
                                                                                                      system employed at Lake  George Village.

                                                                                                      The remainder of the homes and small commercial establishments scattered
                                                                                                      around the perimeter of  the Lake are served by individual, on-lot disposal
                                                                                                      systems usually consisting of septic tanks and drainfields.
                                       G5-4
                                                                                                                                        65-5

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FIGURE 2 - LAKE GEORGE MONITORING BASINS AHO SAMPLING SITES
                     ' direct cunofl

                     > drainage basin no.
                           G5-6
                              PROJECT AREA


I.    Catchment Name - Cedar Lane Storm Sewer (37)

     A.    Area - 76.2 acres.

     B.    Population -     persons.

     C.    Drainage - The Cedar Lane storm sewer drains Into East Brook
          approximately 10 feet south of a culvert carrying the Brook under
          Beach Road and Into the Lake.  The main channel Is 1650 feet at
          a slope of approximately 996 ft/mile and for the last 328 feet
          flows through corrugated pipe.

     D.    Sewerage - 9.64X of the drainage area Is served by separate storm
          sewers; 90.36% has no sewers.

          Streets consist of  .74 lane-miles of asphalt In good condition
          and .48 lane-miles of other materials 1n poor condition.

     E.    Land Use

          4.48 acres (6%)  is 0.5 to 2 dwelling units per acre urban residential,
          of which .62 acres (14%) is  Impervious.

          27.52 acres (36<) Is Linear Strip Development,
          of which 3.38 acres (12X)  Is  Impervious.

          44.16 acres (58X) is Forest.

          5X  impervtousness in entire drainage area.

 II.  Catchment Name  - West  Brook (38)

     A.   Area - 5337.6 acres.

     B.   Population -     persons.

     C.   Drainage - West  Brook, with  several  tributaries,  flows  northeasterly
          and enters the Lake  at the south  end.   The main channel  is  26400 ft.
          with  a slope of  approximately 433 ft/mile.

     0.   Sewerage - 0.27X of  the drainage  area  Is  served by  separate storm
          sewers;  99.73X of the catchment has  no  sewers.

          15.29  lane-miles of  streets  are asphalt (92% in good  condition,  5%
           in  fair  condition and 3X  in  poor  condition); 18.7 lane-miles of
          streets  are concrete (100* in good condition);  .36  lane-miles are
          of  other materials  (53*  in good condition and  47* in  poor  condition).

     E.   Land  Use

          22.04 acres (<  IX)  is  0.5 to 2 dwelling units  per acre urban residential,
          of  which 2.91  acres (13%)  is Impervious.
                                                                                                                             G5-7

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          119.37 acres (2X) is Linear Strip Development,
         of which  18.43 acres (15X) is impervious.

          15.60 acres (< IX) is Urban Parkland or Open Space,
         of which  .33 acres (2%) is impervious.

          166.21) acres (3XJ is urban inactive, of which
         0.62 acres (< IX) is impervious.

          75.29 acres (IX)  is Urban (other),
         of which  23.57 acres (31X) is impervious.

          2.75 acres (< IX) is Agriculture.

          4894.17 acres (92X) is Forest,
         of which  19.50 acres (< IX) is  impervious.

         42.24 acres (IX)  is Mater, Lakes.

111.  Catchment Name'- Sheriff's Dock Stonn Sewer (39)

     A.    Area - 552.3 acres.

     B.    Population -    persons.

     C.    Drainage  - Sheriff's Dock storm sewer discharges directly into the
          lake on the western shore at the south end through a 117 cm concrete
          pipe.  The main channel is 5280 feet with a slope of approximately
          610 ft/mile.  The last 600 feet of the main channel and 1198 feet
          of a triburtary flow through metal pipe.

     I).    Sewerage  - 3.66X  of the drainage area Is served by separate storm
          sewers; 96.34X of the drainage  area has no sewers.

          9.75  lane-miles of streets are  asphalt (74X in good condition, 24%
          in fair condition. 2X  in poor condition); 5.11 lane-miles of streets
          are concrete (100*  in good condition).

     t.    Land Use

          71.32  acres (13X) is 0.5 to 2 dwelling units per acre urban residential.
          of which  18.10 acres (25X) is  impervious.

          32 acres  (6X)  is  Linear Strip Development,
          of which  12.23 acres (38X) is  Impervious.

          7.04  acres  (IX)  is Urban Parkland or Open Space,
          of which  0  acres  (OX)  is  impervious.

          14.08  acres  (3X)  is Urban  Inactive,
          of which  0  acres  (OX)  is  impervious.
                                    65-8
          26.60 acres (5X)  is Urban (other),
          of which 4.63 acres (17X) is impervious.

          401.28 acres (73X)  is Forest.
          of which 2.07 acres (IX)  is impervious.

IV.   Catchment Name - Marine  Village Storm Sewer (40)

     A.    Area - 163.2 acres.

     B.    Population -   persons.

     C.    Drainage - Originally an  above-ground  stream,  reconstruction prior
          to 1926 channelized the stream and  filled a  wetland of considerable
          size.   Presently  Marine Village Storm  Sewer  originates in a farm pond
          (from which water discharges all year)  and flows easterly, discharging
          through a metal pipe directly  into  the lake  on the western shore
          approximately 2000  ft. from the south  end.  An intermittent tributary
          collects drainage from Interchange  22  of  interstate 1-87.   The main
          channel Is 1980 ft. with  a slope of approximately 887 ft/mile;
          approximately 1312  ft. of the  main  channel flow through corrugated
          metal  pipe.

     0.    Sewerage - 7.31X  of the drainage area  Is  served by separate sewers;
          92.69X has no sewers.

          6.78 lane-miles of  streets are asphalt  (60X  in good condition,
          40X in fair condition); 3.31 lane-miles  are  concrete (100X in good
          condition); .26 lane-miles are of other materials (100* in fair
          condition).

     E.    Land Use

          35.84  acres (22X) is 0.5  to 2  dwelling  units per acre urban residential,
          of which 12.38 acres (35X) is  impervious.

          17.28  acres (11X) is Linear Strip Development,
          of which 6.55X acres (382) is  impervious.

          15.36  acres (9X)  is Urban Parkland  or Open Space,
          of which 0.42 acres (3X)  is impervious.

          14.72  acres (9X)  is Urban Inactive.
          of which 0.14 acres (IX)  is impervious.

          42.24  acres (26X) is Urban (other).
          of which 25.99 acres (62X) Is  impervious.

          37.76  acres (23X) is Forest,
          of which 0.48 acres (IX)  is impervious.
                                                                                                                                    G5-9

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                                                                                                                             PROBLEM
Catchment Name -  English  Brook  (41)

A.   Area - 5248 acres.

B.   Population -    persons.

C.   Drainage - English Brook  flows  In a southeasterly direction, entering
     the lake on the western shore approximately 4000 ft. from the south
     end of the lake.  The main channel Is 36,630 ft. with a slope of
     approximately 2072 ft/mile.  Highway, commercial and residential
     development adjoin the brook within 11,000 feet of  the mouth.

0.   Sewerage -  .IX of the drainage area 1s served  by separate
     sewers;  99.9X of the area has no sewers.

     24.4  lane-miles of  streets or highway are asphalt  (100X In  good
     condition); 35.03 lane-miles of  streets or highway are concrete
     (100% In good condition).

 E.   Land  Use

      32 acres (IX)  Is  0.5 to 2  dwelling  units per acre urban residential,
     of which 3.96  acres (12X)  Is Impervious.

      62.28 acres (IX)  Is Linear Strip Development,
      of which 7.29  acres (12X)  Is impervious.

      8.96 acres (<  IX) is Urban Parkland or  Open Space,
      of which 0 acres (OX) Is Impervious.

      11.52 acres is Urban Inactive, of which
      2.09 acres (18X) Is impervious.

      135.68  acres (3X)  is Urban (other),
      of whicjj 39.89 acres (29X)  is impervious.

      23.68  acres (< IX)  is Agriculture.'

      4956.77 acres  (94X)  is Forest,
      of which  20.56 acres  (<  IX) Is  Impervious.

       1.84 acres (<  IX)  is  Water, Reservoirs.

       14.69 acres (< IX) is Wetlands.
 A.    Local  Definition  (Government)

 Every summer,  inhabitants of New York  City,  Albany,  Schenectady, Utica,
 Syracuse, Springfield, Hartford, New Haven,  Montreal,  and other northeastern
 cities concentrate  in  a narrow strip around  the  southern basin of Lake George.
 The population  increases tenfold from  about  5000 people to about 50,000 people,
 renewing annually,  if  temporarily, urban pressures upon the  area.  The reason
 for this migration  is  the quality of the environmental experience available.
 Central to  that experience  is the water quality  of Lake George.

 From  1974 to 1978,  the algae population in South Lake  George has increased
 logarithmically.  The  Lake  is not eutrophic  but  the  condition  Is incipient  as
 reflected in the chlorophyll a data reported by  Wood and Fuhs  for 1978.  The
 residence, or flushing, time Tn the southern basin of  Lake George is eight
 years.  Therefore,  anything wrong with the Lake  will take years to correct.
 If corrective actions  are not taken In the next  decade, an invaluable water
 resource impacting  thousands of people may be  lost.  Reductions in recreational
 use caused by declines in water quality have been documented for a number of
 Lakes  In New York State.  Candarago Lake and Saratoga  Lake are examples.

 The water quality problem In Lake George appears to  be related to phosphorus In
 the water body.  Since anoxic conditions have not been observed, it is unlikely
 that  the bottom sediment of the Lake is the  source of  the troublesome phosphorus.
 Rather, the phosphorus very likely Is dissolved  in the water discharges,such
 as urban runoff, coming from the land surrounding the  Lake.

 Incipient eutrophtcatfon is not the only problem facing the Lake.  Dr. C.R. Goldman
 in his review of Lake George in 1978 presents the following  account:

     "Mr. C.G. Suits of the Lake George Association  has noted that
     bacterial pollution was the major problem in the Lake; total
     colfform counts for 1977 were 11,500, while the maximum allow-
     able for water contact recreation Is 2,400.   Hazen and Sawyer
     (1975)  also noted occasional high coll form counts ... the
     southern basin of Lake George has supported a noticeable growth
     of planktonic blue-green algae during the sunnier months.
      In addition, there have been more frequent complaints by residents
     about near-shore growth of other types  of algae (Hazen and Sawyer
     1977).

     The difference in limnological characteristics between the north
     and south basins provides the most substantial evidence that hunan
      impacts are causing changes in water quality.   It Is not likely
     mere coincidence that the south basin is much more populated and
     also more productive that the north basin (Aulenbach and Clesceri
     1977;  Ferris and Clesceri 1977a)."

Other existing problems Include bacteriological  levels that exceed water quality
standards and sediment deposition which is impairing stream usage and contri-
buting to takeshore silting.  Perhaps the most dramatic example of  sedimentation
 is the emergence of deltas at the mouth of feeder streams.   Sediments deposited
                                 65-10
                                                                                                                                 G5-11

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 in  the  streams  and  in  the Lake are adversely affecting the food-producing,
 spawning  and  nursery potential of the Lake.

 It  appears  that 'a significant  part of any program to preserve the Lake's high
 water qua!ity must  be  land-based control  of urban runoff.

 8.   Local  Perception  (Public  Awareness)

 Widespread  public concern for  the water quality of Lake George is evident  in
 the number  of studies  of  the Lake conducted over the last dozen years, many
 of  than sponsored by citizen organizations of one kind or another.  Six studies
 of  stream chemistry have  been  conducted and nine nutrient budgets have been
 prepared  for  the Lake  since  1971 and the  Lake George Park Commission has sampled
 storm sewers  tributary to the  Lake for bacterial quality since 1973.  Much
 of  this study was triggered by public alarm over extensive algal blooms which
 have occurred from  time to time during the sunnier months.  The Lake George
 Association,  with a current membership of 3000 residents of the Lake George area,
 has been  working since 188S solely to preserve the quality of the Lake.  A Lake
 George NURP Advisory Group comprised of IS members representing the Lake George
 Park Commission, the Lake George Association, public officials, other public
 interest  groups and the citizens at large regularly meets with project staff
 to review progress  and provide comments and has conducted several public
meetings  to inform  the communities about  project-goals and accomplishments.
 Articles  on urban runoff,  its  probable impact on the Lake and the need to control
 it regularly  appear in the six local  newspapers serving the communities sur-
 rounding  the  Lake.
                                     G5-12
                         PROJECT DESCRIPTION


A.   Major Objectives

The major technical  activities  taking place  ir. the Lake George study arc:

     1.   Identification of  all major stormwater  sources  in the highly developed
          southern portion of the Lake George Basin;

     2.   Quantification (in terms of concentration and load) of the major
          stormwater contaminants discharged to the Lake;

     3.   Assessment of the  contribution of  phosphorus and fecal bacteria to
          south Lake George; and

     4.   Baseline monitoring of selected  tributaries.

Essentially these activities are intended  to provide an assessment of the
temporal and spatial generation of the various stonnwater contaminants, their
delivery to south Lake George,  and the loadings attributable to stormwater,
especially those for phosphorus.  The findings will be used in the formulation
of an overall urban runoff management strategy for the Lake to be funded at a
later date from other sources.

Stormwater inputs to Lake George are generated by two major sources: 1) the
densely populated residential/commercial area from Lake George Village to
BoIton landing and,  2) the major highways  (Interstate 87  - the Adirondack
Northway - and New York State routes 9, 9L and 9M). that  cross the watershed.
Specific sources and impacted tributaries  have been sampled and measured on an
event basis to determine concentration and load of the several pollutants
including complete scans for priority pollutants  on a limited number of samples.
The storm drains and streams designated for  study give spatial distribution
over the area such that major source zones can be identified.

The contribution of pollutants  from both dry and  wet atmospheric fallout is
being determined in addition to the contributions from stormwater and septic
systems.

8.   Methodologies

An historical data review was completed and  submitted to  USEPA on December 1, 1980.

A storm sewer map was developed for the Village and Town  of Lake George.  This
was essential to delineate the drainage of each catchment within the study area.
Field surveys established the storm sewer  system  and the  catchment boundaries.

Land use estimate have been  updated using  aerial  photographs from 1948, 1958,
and 1968, LUNR series maps (Shelton et a!.,  1973) and 1976 aerial photographs.
                                                                                                                                     G5-13

-------
Verification of the land uses  within  the study area was carried out by NYSDEC
personnel.  Estimates for Impervious  areas have been calculated for all catch-
ments within the study area.

The developed areas consist of private residences and commercial establishments
related primarily to tourism and  recreation.  All travel, which is quite heavy,
is essentially by automobile.   There  Is no significant Industry within the
basin.  The following land uses occur within  the five basins chosen for runoff
sampling and measurements:

     *    mixed residential/coroner leal;
     '    transportation (roads);
     *    urban open space; and
     *    forested, brush and  open  land.

The relatively large amount of undeveloped land which surrounds the urban areas
constitutes a major part of most  of the monitored basins.  For this reason an
additional monitoring site was established during the summer of 1981 upstream
of the urban area In one of the basins to determine background runoff loadings
for comparison with the loadings  generated within the urban areas.

A total of forty atmospheric deposition samples were submitted for chemical
analysis during the first year of the study.  These Include twenty-five wetfall
samples, six dryfall 'samples and  nine sanples from the bulk collector.

The monitoring of priority pollutants was not carried out during the first year,
but is scheduled for completion by  June, 1982.  Sample collection will be
carried out by NYSOEC personnel and sample analysis will be conducted by
laboratories at the NYS Department  of Health.

A review of historical data for the near-shore area of Lake George was completed
during the first year.  Hater  quality In the  near-shore area has received little
previous attention.  Host of the  sampling programs have been carried out in the
deeper waters.  Therefore, a limited  sampling program for near-shore areas of
the Lake was established to determine baseline water quality and the response
of Lake water quality to storm events.  To determine the Impact of stormwater
runoff on the Lake, the phytoplankton community response was analyzed.  Algal
assays were conducted to determine  the availability of nutrients in the open
waters.  Lake sampling was conducted  only during the first year of the project.

C.   Monitor ing

The study area consists of two strean watersheds (West Brook and English Brook)
and three storm sewer catchments  (Cedar Lane, Sheriff's Dock and Marine Village)
located at the extreme southern end of Lake George.  A sampling station re-
cently established to determine runoff  loadings from undeveloped open land is
located In the Shetff's Dock catchment west of the Village of Lake George and
Interstate 1-87.

The major land use within the  West  Brook watershed  is forests.  Urban areas
constitute a small part of the area (7.5%), all located  immediately adjacent
to the Lake.  The predominant  land  use  in  the English Brook watershed is
forest (91.7*).
                                     G5-14
All development  Is located adjacent to the Brook,  is highway, commercial  or
residential  in nature and  is within two miles of the mouth.  The  predominant
land uses within the Cedar Lane storm sewer drainage are  forest (58.0%)  and
urban (42.OX), approximately 86% of the latter being commercial.   In  the
Sheriff's Dock drainage basin, forests constitute  the  greatest proportion of
land use (72.6%).  Urban areas, although only 27.4% of the total  basin,  are
concentrated east of Interstate 1-87 within the Village of Lake George  and are
44.6% Impervious.  Urban areas constitute the predominant land use  (76.9%)
within the Marine Village basin, approximately 60% of  which  falls within  the
boundaries of the Village of Lake George.  The total Impervious area  for  this
portion of the drainage basin Is 25.45%.  The remaining land area is  forested
(23.1%).

Atmospheric  sampling, Including wetfall/dryfall and bulk, was conducted
originally at a point within the West Brook drainage basin near the Lake  but
has been shifted to a location within the Cedar Lane Storm Sewer  basin  for
the remainder of the project due to interference from  trees  at the  first
location.

Collected samples are analyzed for the following constitutents: nitrogen,
phosphorus,  suspended solids, chloride, sodium, lead,  bacteria, pH, conduct-
ivity, alkalinity and temperature.  In addition, other paraneters listed  In
the USGS/EPA Urban Hydrology Studies Program will  be analyzed for as  necessary.
Location

Lake George V.
  Village
West Brook
English Brook
Cedar Lane
Sheriff's
Dock
Marine
  Village
Type

Atmospheric
Fallout
Streams
                         Stormsewer
Stormsewer
                         Stormsewer
Equipment

Aerochemetrics, Inc., wet/dry
deposition collector, bulk
precipitation collector and
weighing bucket recording
precipitation collector.

Manning S-4050 automatic
sampler, liquid-level actuated
STACOM-7735 gas purge servo
manometer, Fisher-Porter ADR-
350, and Stevens chart
recorder type A35.

ISCO 2100 automatic flow
proportional sampler, ISCO 170
flow meter with ISCO 1710
printer, 53 cm Palmer-Bowlus
Flume.

Manning S-4050-2 automatic
sampler, liquid-level actuated
or flow proportional, Harsh-
He Birney Flowmeter Model 250.

Manning S-4050 automatic
sampler, liquid-level actuated
or flow propotional, Marsh-
McBirney Flowmeter Model 250.
                                                                                                                                    G5-15

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D.   Controls

The original work plan for this project provided for the evaluation of control
measures and development of a stormwater control management plan in the second
and third years of the project if the sources of phosphorus and other nutrients
entering the southern portion of the Lake could be pinpointed as a result of the
first year's monitoring and analysis efforts.  Because isolation of those sources
proved to be more difficult than originally anticipated, it was decided to
drop evaluation of controls and development of a management plan in favor of
modifying and continuing the monitoring and analysis tasks.
                                 G5-I6

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IRONDEQUOIT BAY,  NEW YORK
               bC-i

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                                                                                                             FIGURE 1 - STATE AND COUNTY LOCUS OF  IRONOEQUOIT BAY
                                                                                                                                   NURP PROJECT
                              INTRODUCTION
Irondequolt Bay Is one of many bays of Lake Ontario located within Hew York
State.  It Is a prime water  resource  for Monroe County In terms of recreational
potential.  Figure 1 shows the general location of the Bay within Monroe County.
A quarter of a million people  presently Inhabit the area tributary to Ironde-
quolt Bay.  It Is truly an urban  receiving water body, being completely sur-
rounded by rapidly expanding urban development.

The Bay Is a relatively shallow body  of water bordered by low-lying areas.
The stormwater generated from  the eastern portion of the City of Rochester
and much of the southeastern portion  of Monroe County drains to Irondequolt
Bay.  Combined sewer overflow  (CSO) discharges also enter the Bay from the
City of Rochester.  These factors have led to * progressive eutrophlcatton
of the Bay which has seriously restricted  Its recreational potential.

The degraded water quality of  Irondequolt Bay and the condition of the benthos
severely Interfere with its  use for bathing, boating, and fishing.  Presently,
the Bay is classified as Class *B* waters by the New York State Department
of Environmental Conservation  (NYSOEC).  Public surveys, however, have Indicated
widespread support for restoring  the  Bay sufficiently to support earlier uses
such as contact recreation.

A comprehensive sewer study  conducted during the late 1960s recommended a
water quality management program  requiring complete diversion from the Bay of
all sewage treatment plant (STP)  discharges and CSOs from the City of Rochester.
The diversion of STP discharges has now been fully completed and a program to
reduce drastically CSO discharges to  the Bay Is well underway.  The expected
Improvement In water quality should move the Bay a long way toward restoration
of Its Identified best uses  -  fishing and swimming.  However, there Is concern
by local officials that urban  stormwater runoff. If allowed to continue to
enter the Bay uncontrolled,  will  deter the full restoration process.
                                    G6-2
IRONDEQUOI
     BAY

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                          PHYSICAL  DESCRIPTION
A.   Area
and
     West  Blooraf ield.

      Population



                           ^^






 w« uttaated it 2M.OM   Asking canplete diversion of Rochester sewerage.
 the effective population would be about  140,000.


 C.   Drainage

 The drainage area is characterized by gently rolling countryside IK* »"''
 streams of various sizes, all of which feed into Irondequoit Creek.   The Bay
 itself Is bordered by steep, wooded hillsides.  The Irondequoit flay Drainage
 Basin (Figure 2) measures 22 miles on the north-south axis  and
         9                                                           f
  flow In Irondequoit  Creek  are not  available, but a stage gauge "« existed
  on Al  en C?2ek  2bout 1 .lie  upstre*. fro.  Irondequoit Creek since 1959   An
  average discharge rate of  168 cubic feet per second near the mouth of the
  Irondlquoit Creek may be calculated based  on the ratio of the Allen Creek and
  Irondequoit Creek drainage areas.
                                                                                                                       FIGURE 2 - PROJECT AREA
                                                                                              N
                                                                                              A
                                                                                                         IRONOEQUOIT
                                                                                                         CREEK 3ASIN
                                                                                                          : I URBANIZED AREA
                                                                                                                                                                FECT
                                      G6-4
                                                                                                                                      G6-5

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IrondequoH Bay Is about 4 miles long and varies  between  1/4  and  1-1/4 miles
In width.  The Bay lies at the mouth of a pre-glaclal  river valley with slopes
rising on either side to about 150 feet over  the  present  water  level.   Depths
vary between very shallow marshes at the northern and  southern  extremities  and
75 feet in the central basin.  Approximately  SOX  of its area  lies over shallows
less than 10 feet deep.  The outlet to Lake Ontario passes under  railway and
highway bridges and Is restricted by a sand spit  to an opening  50 feet wide
and 200 feet long.  The depths at the outlet  range between a  few  Inches and
4 feet.  Flow at the outlet Is variable and restricted, depending on oscillations
in Lake levels due to wind direction and barometric pressure  differences as
well as on variations In the discharge of Irondequott  Creek.  Nixing between
the Bay and Lake Ontario is limited.

D.   Sewerage System

The area within the Rochester city limits (figure 2) In the northwestern corner
of the drainage area is served by combined sewers which are part  of the $80
million  program to reduce CSOs to a once-ln-ftve-year frequency.  The urbanized
areas outside the City of Rochester and excluding the  township  of Hendon and
Victor are served by separate storm sewers which  discharge Into the creek
system and by sanitary sewers which, along with the combined  sewers within  the
City limits, flow to the Van Lare treatment plant, Rochester's  250 MGD secondary
treatment facility which discharges directly  InU Lake Ontario.  The areas  of
Mendon and Victor townships lying within the  Irondequoit  Creek  watershed are
rural and unsewered.
                                     G6-6
FIGURE 3 - MONITORING SITES
           AND  RELATED DRAIN-
           AGE  BASINS
                 ^
                                                                                           Bail n Boundary ••"—•
                                                                                           Town Un» ——
                                                                                           C/Mfc —	
                                                                                           County Un«
                                                                                           Cllv DM	
                                                                                           Land UN Monitoring
                                                                                              Sit* Orataaq* Bain

                                                                                           Uonitartng Located

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                              PROJECT AREA
I.    Catchment Name - East  Rochester.

     A.    Area -.384 acres.

     B.    Population - 6836 persons.

     C.    drainage - This catchment  area has  a representative slope of 58.08
          feet/mile. SOX served  with curbs  and gutters and 10X served with
          swales and ditches.  The storm sewers approximate t 15.84 feet/mile
          slope and extend  7600  feet.

     0.    Sewerage - Drainage  area of  the catchment  is 100% separate storm
          sewers.

          Streets consist of 25.09 lane ulles of asphalt. 75X of which is in
          good condition. 20X  of *4»ich is in  fair condition, and 5X of which
          is in poor condition.   There is no  concrete or other roadway In the
          catchment.

     E.    Land Use

          384 acres (100X)  is  2.5 to 8 dwelling units per acre urban residential.
          of which 146 acres (38*) is  impervious?

11.  Catchment Name - Balrd Road (Thomas Creek)

     A.    Area - 18.240 acres.

     B.    Population - 24,618  persons.

     C.    Drainage - This catchment  area has  a representative slope of 232.32
          feet/mile. 8X served with curbs and gutters and 2X served with swales
          and ditches.  The storm sewers approximate a 15.84 feet/mile slope
          and extend 56.496 feet.

     D.    Sewerage - Drainage  area of  the catchment  is 10X separate storm sewers
          and 90S unsewered.

          Streets consist of 186.37  lane miles of asphalt. 90X of which is  in
          good condition and 1C* of which is  in fair condition, and 19.03 lane
          miles of other material, 90X of which is in good condition and 10% of
          which is in fair  condition.

     E.    Land Use

          18,240 acres (100X)  is < 0.5 dwelling units per acre urban residential.
          of which 1920 acres  (11X)  is impervious.
                                       G6-8
III. Catchment Name - Southgate

     A.    Area - 177.2 acres.

     S.    Population - 250 persons.

     C.    Drainage - This catchment  area has a representative slope of 300.96
          feet/oille. S8X served with curbs and gutters and 3X served with swales
          and ditches.  The storm sewers approximate a 36.96 feet/mile slope
          and extend 2150 feet.

     D.    Sewerage - Drainage  area of the catchment is 60X separate storm sewers
          and 40X no sewers.

          Streets consist of 2.75 lane miles of asphalt. 95X of which is in
          good condition and 52 of which Is in fair condition.

     E.    Land Use

          177.2 acres (100X) Is Shopping Center
          of which 37.7 acres  (2U)  is impervious.

IV.  Catchment Name - Thornell  Road

     A.    Area - 28.416 acres.

     B.    Population - 5950 persons.

     C.    Drainage - This catchment  area has a representative slope of 279.84
          feet/mile. ,2SX served with curbs and gutters and 4.75X served with
          swales and ditches.   The storm sewers approximate a 15.84 feet/mile
          slope and extend 82.360 feet.

     D.    Sewerage - Drainage  area of the catchment is 5X separate storm sewers
          and 95X no sewers.

          Streets consist of 255.75  lane miles of asphalt, 90X of which is in
          good condition and 10X of  which is in fair condition.  In addition
          there are about 13.62 lane miles of concrete, of which 90X is In
          good condition and 10X is  in fair condition, and 25 lane miles of
          other material, of which 90X is in good condition and 10X is in
          fair condition.

     E.    Land Use

          28.416 acres (100X)  is Agriculture, of which
          1051 acres (4X) is Impervious.
                                                                                                                                   G6-9

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V.   Catchment Name - Cranston Road

     A.    Area - 167.6 acres.

          Population - 900 persons.
B.

C.




D.
          Drainage  -  This  catchment area has a representative slope of 174.24
          feet/mile,  68X served Mith curbs and gutters and 22X served with
          swales  and  ditches.  The storm sewers approximate a 84.48 feet/mile
          slope and extend 2850 feet.

          Sewerage  -  Drainage  area of the catchment Is 89.6X separate storm
          sewers  and  10.« no  sewers.

          Streets consist  of 8.67 lane miles of asphalt. 100X of which Is In
          good condition.

    E.    Land Use

          167.6 acres (100X) is  0.5 to 2 dwelling units per acre urban resident)!
          of which  36.3  acres  (22X) Is Impervious.
                                     G6-10
                                                                                                                             PROBLEM
A.   Local Definition (Government)

A dense algal crop occupies the surface waters of the Bay continuously from
early Hay to mid-October.  Deep sediments (characterized by citizens  as
"black muck0) underlie the Bay waters.   Spring mixing in the Bay  is often
Incomplete and In the fall is often delayed.   These conditions  have been related
to the accumulation of roadway de-Icing salts In the deeper waters.   Algae
and other organic matter sink to the bottom of the Bay.  where decomposition
during winter and summer stratification consume all of the dissolved  oxygen
In the bottom waters and generate high  concentrations of ammonia,  phosphate,
and hydrogen sulflde.

A comprehensive sewer study conducted during  the late 1960s recommended a
water quality management program to enhance water quality in the  Bay.  The
program, which was eventually adopted,  required complete diversion from the
Bay of all sewage treatment plant (STP) discharges and CSOs from  the
City of Rochester.  Extensive llmnological studies of the Bay ecosystems
were also conducted.  These studies provided  the data base to properly
evaluate the Impact of the proposed wastewater diversion program.  All of
these studies Indicated that Irondequolt Bay  was beginning to approach a
nutrient limiting condition and that a  significant reduction In phosphorous
loadings would be necessary to arrest and reverse the water quality deg-
radation of the Bay.

Figure 4 Indicates the dramatic reduction In  phosphorus  loadings  to the Bay
which has been accomplished by the STP  effluent diversions and  partial CSO
relief.  The average daily phosphorous  loading to the Bay has decreased from
238 kg P/day to 62 kg P/day since 1977  as the discharges from 16  STPs have
been diverted.  Additional reduction will be  realized when an ongoing
Rochester CSO pollution abatement program Is  completed.   This program In-
volves construction of the Culver-Goodman Tunnel complex on the east  side
of the city.  While completion of this  program is expected to reduce  phos-
phorous loadings further, It will not lower them to the  16 kg/day level
required to control the algal productivity of the Bay.  Consequently  nonpoint
source controls are essential to restore, and maintain acceptable water quality
In the Bay.

Specifically, there Is concern by local officials that urban stormwater runoff,
if It continues to enter the Bay uncontrolled, will deter the full restoration
process and may even reverse It.

While much Is known about Irondequott Bay from previous  studies,  the  Impact
of further pollutant loading reductions by the control of urban stormwater
runoff has yet to be adequately demonstrated.  The relative magnitude of
the remaining urban runoff pollutant loading  and the cost-effectiveness of
further reductions require further study.  Furthermore,  If It appears cost-
effective to reduce the urban stormwater runoff component of the  Bay's
pollutant Inputs, evaluations must continue In order to  formulate control
strategies for dealing with the urban runoff  problem.
                                                                                                                                    06-11

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FIGURE 4 - REDUCTIONS IN PHOSPHORUS LOADINGS  TO IRONOEQUOIT BAY
           FOLLOWING STP EFFLUENT DIVERSIONS  AND PARTIAL CSO RELIEF
             log i|en6«puai| o| Buipocr)
                                  G6-12
8.   Local Perception (Public Awareness)

Clear indication of the extent of citizen concern for water quality in the
Bay has been shown by public support of the $130 million already spent
to divert STP effluents from the bay and of the ibO million presently being
spent to reduce CSOs.  Newspapers, radio and television consider efforts to
clean up the Bay newsworthy and generally give such efforts excellent
coverage, another Indicator of widespread citizen interest  in the water
quality of the Bay.  To some extent, public concern for the Bay is a matter
of re-education as water quality in the Bay has been on the decline for
aany years and Its widespread use for contact recreation is beyond the personal
memories of most of Its current citizens.  As word of the NURP study has spread.
however, citizen interest In the future Improvement of the  Bay has grown markedly.
                                                                                                                          G6-13

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                         PROJECT DESCRIPTION
A.   Major Objective

Simply stated,  the primary objective of the  Irondequott Bay National Urban
Runoff Program  (IBHURP) 1s to establish the  significance of the Impact of
urban runoff upon the Mater quality of Irondequott Bay and to put It Into per-
spective with other nonpolnt sources.  The problems associated with
Irondequott Bay - hypollronetic oxygen depletion, turbidity, and adverse
fishery Impacts - result from the grossly over-productive status of the Bay
and have been well documented.  The problems are very clear; the causes of
the problems are not clear.  Controls for diverting all point source dis-
charges Involved the expenditure of $130 nillion and are presently operating.
Controls for reducing CSOs to a once-ln-fIve-year frequency have been designed
and are presently under construction.  The amount of reversal In Bay
eutrophteat ion  that will result from these controls, however, has yet to
be fully determined.  The missing element now Is assessment of the-signi-
ficance of urban stormwater runoff as a contributor to eutrophteat ton.

A second, and equally Important objective. Is to determine the effectiveness
of primarily non-structlonat controls In reducing the  Impact of urban runoff.
Accordingly, various management options Involving Best Management Practices
(BHPs) which are currently being evaluated by a USEPA Great Lakes Initiative
Grant Program for the City of Rochester will be reviewed for applicability
to the Irondequolt Bay drainage basin.  The effectiveness of control measures
will be evaluated  separately, and  In various combinations.  Since commit-
ments have already been made to both point source  and CSO control, the merits
of urban runoff control can be more definitively specified  and understood
more pragmatically.

B.   Methodologies

The sources and magnitude of the pollutants must be determined before specific
control measures can be  formulated  to abate the present  storm-Induced con-
tamination  In runoff entering the  Bay.  The Irondequolt  Bay drainage basin
 Is comprised of urban,  suburban, and rural or agricultural  areas.   Therefore.
one major  task of the overall program  Is  to determine the magnitude and  fre-
quency of  specific  pollutant  loadings from typical  urban land  uses. Including
highways  and roads,  and  to  differentiate  these loadings  from  those  originating
from  undeveloped land.

To. determine the pollutant  loadings associated with different land  uses, five
monitoring sites were established.   Each  site has an associated  tributary
drainage  area  that Is relatively small  In relation to the entire Irondequolt
Bay basin.  Because of this,  boundaries for each area can be accurately
established and the runoff  measurements and sampling easily conducted.
Monitoring of  small, well-defined  watersheds will allow for reliable  and
 accurate  pollutant runoff determinations and easy Identification of the
 sources of these contaminants.   Estimates of present and future runoff loads
 to the Bay will be based on transferring and extrapolating the data collected
 from these five different land use sites.
 At  present,  a full year's monitoring program,  Incorporating both dry weather
 and storm samples and seasonal variations, has been conducted at all five
 land use  sites.   Less frequent monitoring has  also  been conducted at two
 •Junction* sites;draining larger sections of the  overall Irondequolt Bay..
 basin and at a wetlands site a few hundred yards  from the point where
 Irondequolt  Creek discharges into the Bay and  which effectively drains the
 entire basin.  The same monitoring program will be  continued for a second year.

 In  conducting  this project,  the Vallenwelder eutrophicatlon model will be
 adapted so that  the contribution of urban runoff  to Bay eutrophIcatIon can be
 evaluated.   The  model will also be used to evaluate the effectiveness of
 overall runoff management schemes on the water quality of the Bay.  A watershed
 model  will be  used to establish the relationship  of rainfall to stormwater
 runoff and pollutant loadings.  Watershed response,  which transfers precipitation
 Input  Into runoff output. Is determined by land use and other physical
 characteristics  which can be estimated during  model  calibration.   One-demensional
 tributary models that address advectlve and dispersive process components will
 be  used to simulate the transport of loads by  the tributaries to  the Bay.  Con-
 straints  will  be imposed on  the models to simulate  the action of  control measures
 and  thereby  establish their  relative effectiveness.

 C.   Monitoring
                                         f        .0.
 Sample collection  and analysis for the Irondequolt  Bay NURP are being performed
 by the U.S.  Geological  Survey (USGS) and the Monroe  County  Health Department
 (MCHO).

 Table  1 summarizes the  land  uses and relative  sizes  of the  five primary
 sampling  sites:
                        TABLE 1.  LAND  USE MONITORING  SITES
                                               Drainage Area
fenltorlng Location      Basin Tributary          «1
                                           Land Use
rhornell Road

•    i —
laird Road (BOCES)

Cranston Road

iouthgata Road

ast Rochester
Irondequoit Creek        44.4


Thou*  Cr«ek             28.5

Irondequott Creek         0.31

Whit* Brook               0.36

Store sewer to            0.61
Irondequolt Creak
Rural


Mixed

Middle  density residential

Coaoerelal

High density residential
                                     G6-14
                                                                                                                              66-15

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                                                                                                           TABU 2.  FLOW MONITORING AMD SAMPLING METHODS
Baseflow samples are collected at  all  sites using methods described by Guy
and Norman to define non-storm or  background concentrations at gaged sites.

Precipitation quality is determined  at three sites using an Aerochemetries Inc.
Model 301 wet/dry fall collector.  A minimum of one continuous precipitation
quantity gage is located in each watershed sampled.  Because of the large
basin area, a network of daily gages for rainfall quantity are operated In the
Irondequoit Bay NURP to supplement continuous precipitation data.
The constituents analyzed In each  sample are:
     Suspended solids.
     Particle size analysis.
     Specific conductance,
     PH.
     Dissolved Solids.
     Dissolved NO., NO,-H.
     Dissolved KJeldahf-N.
     Total Kjeldahl-N.
     Dissolved Phosphorus-P,
     Total Phosphorus-P,
     Dissolved Sodiun-Na,
     Dissolved Calcium-Ca,
Dissolved Hagnesiin-Hg.
Dissolved Potasslun-K,
Dissolved Chloride-Cl
Dissolved So.
Alkalinity a? CaCo,.
Dissolved Organic Carbon,
Suspended Organic Carbon,
Chemical Oxygen Demand.
5-Day BOD.
Ultimate BOD. and
Fecal Collfonu.
Sampling and streamflow equipment  at the  Irondequoit Bay collection sites are
maintained by USGS and Monroe  County personnel.  All samples are returned as
soon as possible after collection  to the Monroe County Health Department
Laboratories for further processing, i.e.. filtering, splitting, preservation.
etc.  The use of this lab provides a nearby well equipped facility with well
trained personnel for sampling processing.

Equipment

Flow monitoring at four of the five land use sites Is accomplished by converting
a stage or depth of flow, the  primary measurement. Into a flowrate according
to a calibrated and verified stage/discharge relationship.  At the East Rochester
site, flow is computed directly by a Harsh-HeBirney electronic head and velocity
meter.  Depth is computed by a pressure sensor, whereas, velocity is determined
by an ultrasonic meter.  All water quality sampling is accomplished by the use
of Manning Corporation flow proportional samplers.  Each of the five monitoring
sites also measures precipitation  by a recording tlpping-bucket rain gauge.  A
suumary of the type of sampler and recording procedure used for runoff flow
monitoring and water quality sampling is presented in Table 2.
                                                    Monitoring
                                                     Location
               Flow Monitoring
                       Sampling
                                                          Rainfall
                                                    Thornall Road
Balrd Road
(BOCES)
Cranston Road
                                                    SouthgaU

                                                    Ea*t
                                                      Rocnastar
Mercury •anoaatar
bubblar gaga-records
In graphical  and 15-
•in digital  fora.
                                      Manning SaopUr
                                      stags-actlvatad
                                      or flowr
                                      proportlonal
                                      saoples.
                                           Volumetric
                                           S *1n digital
                                           output
Stilling wall-float
ntlwd-rvcords In
graphical  and IS din
digital fora

SaM as Thormll Road -
axcapt racords In S ain
digital fora

Sana as Cranston Road  -
                                                —Sao* as Thornatl  Road
                                                  -Sam as Thornall  Road
                Manh-Mcairney
                flowMtar
                        .as Thorn*11 Road
                                                 Controls

                                                 A wide variety of control measures have been investigated for possible use in
                                                 the Irondequoit Bay basin.  Probable candidates include Increased use of porous
                                                 pavement in developing areas. Improved solid waste management procedures.
                                                 erosion and sedimentation control regulations, chemical use ordinances and
                                                 related public Information programs, modification df highway deicing practices.
                                                 industrial spill control ordinances, mlscroscreening and swirl concentrators
                                                 (depending upon monitoring results with regard to particles size and associated
                                                 nutrients), detention and retention basins and swale drainage.  Because of
                                                 the presence of a large wetlands area near the mouth of Irondequoit Creek,
                                                 this technology offers great promise in this watershed.  Considerable discussion
                                                 has already addressed the possibility of installing a control structure on the
                                                 outflow from the wetlands to maximize detention tine and.  presumably, nutrient
                                                 uptake.   However, this would have to be done carefully as. according to some
                                                 of  the available literature, microbial activity is the most important mechanism
                                                 for phosphorus reaoval and this activity decreases If the  soil is submerged and
                                                 becomes  anaerobic.  In any case, because of the length of  time required for
                                                 adequate evaluation it is highly unlikely that significant results can be
                                                 obtained by the end of the NURP project period and therefore wetlands evaluation
                                                 would  have to be conducted as a separate project.
                                  (16-16
                                                                                                                              G6-17.

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          NATIONWIDE URBAN RUNOFF PROGRAM

  METROPOLITAN WASHINGTON COUNCIL OF GOVERNMENTS
          Water Resources Planning Board
                In Association With
  Northern Virginia Planning District Commission
                      And The
Virginia Polytechnic Institute and State University
                  REGION III, EPA
                     G7-1

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                                INTRODUCTION
The metropolitan Washington area extends for approximately  2400  square miles cen-
tered on the District of Columbia.   The major receiving waters include the
Potomac River and Estuary,  the Patuxent River and  the Occoquan Creek and River.
These rivers and estuary systems provide important freshwater and  low salinity
spawning aras for anadromous fish populations off  the Atlantic coast from Maine to
Florida.  Further these river systems  provide the  source  of a valuable product,
drinking water, for the entire metropolitan Washington area.

The water quality problems  Include destruction of  spawning  areas,  reduction in
storage capacity of the Occoquan reservoir from excessive upstream erosion, and
eutrophtc levels of algae production.

The project is (1) evaluating BMP effectiveness of source,  volume  and detention
controls, (2) determining capital and  operation, maintenance and repair costs of
BHP's, (3) scanning 128 priority pollutants, (4) refining runoff data in central
business district areas, (5) monitoring and analyzing the contribution of atmos-
pheric sources to urban nonpoint source loads, (6) conducting critical watershed
studies to apply runoff relationships, refine data transferability and identify
nonpoint source management  options, and (7) conducting a  public  participation
program.

The Washington NURP project participation represents a unique cooperative ventures
of government and the business community.   The project is being  coordinated and
administrated by the Metropolitan Washington Council of Governments (COG) and its
Water Resources Planning Board (WRPB).

Since 1975, the WRPB has been responsible for areawide wastewater  management plan-
ning for the metropolitan region under provisions  of Section 208 of the Federal
Water Pollution Control Act Amendments of 1972.  The WRPB Is composed of represen-
tatives of the executive and legislative branches  of COG's  16 member jurisdic-
tions.  Members also include representatives from  the State of Maryland, Virginia,
and the District of Columbia (through  its responsibility  for state certification
of the 208 areawide water quality management plan); the  Interstate Commission on
the Potomac River Basin (ICPRB), and the Northern  Virginia  Planning District Com-
mission (NVPDC).

Technical staff assistance  of the WRPB Is provided by the COG Department of En-
vironmental Programs (OEP).  OEP is responsible for all of  the project's program
management activities.   Other COG participating departments include its Office of
Computer Services and Office of Public Participation.

The project was developed and is being carried out in association  with the Nor-
thern Virginia Planning District Commission (NVPDC) and the Virginia Polytechnic
Institute and State University (VPI).   VPI is responsible for all  sample collec-
tion and analysis, with the exception  of priority  pollutant scan analysis, which
has been subcontracted to a private research/engineering  firm.   NVPOC  is responsi-
ble, in conjunction with VPI and COG,  for evaluating  lab  data from specified BMP
monitoring activities and land use/runoff correlation studies.   VPI and NVPDC are
generally recognized as national leaders in research and  data applications  involv-
ing nonpoint source assessments.
                                  67-2
Both agencies were associated with COG  in earlier 208-related studies and planning
efforts.

The National Association of Home Builders (NAHB)  and the Northern Virginia Buil-
der's Association (NVBA) are also providing  financial support, and periodic tech
nical input to this project.  To date,  the associations have provided assistance
in site selection and development of  unit cost  survey information for the BMP pol-
lutant removal efficiency and cost studies.   The  NAHB and NVBA have also partici-
pated on the WRPB Nonpoint Source Task  Force (NPSTF), a group which includes
engineers and planner from area  local and state governments as well as business
and citizen group interests.
                                                                                                                                  67-3

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                                PHYSICAL DESCRIPTION
A.  Area

Tlie Washington, DC.  metropolitan region is an area of approximately 2,400 square
miles, located within the Potomac River Basin and a major portion of the
Patuxent River Basins (See Figure 1).   Us principal urban areas are situated at
the heail of the Potomac Estuary.  Free-flowing sections of the Potomac River pro-
vide 60 percent of the region's drinking water, with one of the estuary's major
tributaries, Occoijuan Creek, supplying an additional thirteen percent.  The upper
Potomac Estuary and its tributaries constitute an important freshwater low salin-
ity spawning area for anadromous fish of the Potomac and Chesapeake Bay.

A majority of the region falls within the piedmont and coastal plain geologic for-
mations.   The region's clay/sandy silt loan soils, found on both formations, are
considered severely erosion prone.   Figure 2 depicts the region's generalized soil
groupings.

6.  Population.

Iliu Washington, DC.  region has a current population of approximately 3 million
persons.   Population growth has traditionally been greatest in area suburbs and
recent growth trend assessments predict this trend will continue, with the suburbs
projected to show over a 40 percent increase in population by the year 2000 as
compared to an 11 percent rate of growth in the inner urban core (District of
Columbia, Arlington County).

Table 1 shows.the current (1977) distribution of land use throughout the region,
and provides a general indication of future development and land use patterns.

C.  Drainage.

There are several hundred streams of varying flow in the region, tributary to both
the free-flowing and estuary portions of the Potomac and Patuxent rivers.   A large
number of these streams are located in older residential or newlydeveloping areas.
Figure 3 shows the metropolitan region, its streams, basins and some of its major
jiirisdictional boundaries.
The urban area is served by a separate sanitary sewer systeal with the exception of
14.UOO acres in the District of Columbia and 650 acres in Alexandria which are
served by combined sewer systems.   Further, approximately 7 to 8 percent of the
population of the metropolitan Washington area is served by on-site (e.g., septic
tank) systems.
                                  G7 4
Figure 1.  The Washington Metropolitan Are* and Potomac River Basin
                                                                                                                                  G7-5

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      I!D!QIBIO;@  I! 01! 110111683;

                      ii
                                                                                 TABLE 1.  LAND COVER IN THE WASHINGTON MEIROPOUTAM AREA
3




I
S
3
f.


I

s
Urban/Suburban Areas
Low-density single family
Medium-density single family
Townhouse/garden apartment
Hi-Rise Residential
Institutional
Industrial
Suburban Commercial
Central Business District
Rural Areas
Forest
Idle
Cropland (Hin. till)
Cropland (Conv. till)
Pasture
Tended Areas
Estimated Total
Percent
Imperviousness
6%
25%
40%
70*
60%
70%
90%
95%
1%
a%
IX
1%
1%
IX
Existing (1977)
Land Cover in
Acres
37,615
137,643
14,689
28,316
43,580
15,011
39,671
3.575
512,585
311,263
61.732
25,933
206,442
68,583
1,506,641
Projected (200)
Land Cover in
Acres
100,885
206,880
17,905
30,391
48,337
23,642
48,029
6,133
436,935
271.982
54.323
22.743
185,176
53,083
1,506,641
                           G7-6
                                                                                                    67-7

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                                                                                                                PROJECT AREA
                                                                             1.    Catchment Name - DC1.  Catchment 001.  Stratton Woods,  Roadside Swale, BMP

                                                                                  A.   Area - 8.461 acres.

                                                                                  B.   Population - No data.

                                                                                  C.   Drainage - This catchment has a representative slope of 64.5 feet/mile,
                                                                                      100% served with swales and ditches.   The drainage channels approximate a
                                                                                      95.0 feet/mile slope,  and extend 1890 feet.

                                                                                  D.   Sewerage - Drainage area of the catchment is 100% separate storm sewers.

                                                                                  E.   Land Use

                                                                                      8.46 acres is 0.5 to 2 dwelling units per acre urban residential

                                                                             II.  Catchment Name - DC1,  Catchment 002.  Dufief. Roadside Swale BMP

                                                                                  A.   Area - 11.84 acres.

                                                                                  B.   Population - No data.

                                                                                  C.   Drainage - This catchment has a representative slope of 449.8 feet/mile,
                                                                                      100% served with swales and ditches.   The drainage channels approximate a
                                                                                      343.2 feet/mile slope, and extend 450 feet.

                                                                                  0.   Sewerage - Drainage area of the catchment is 100% separate storm sewers.

                                                                                      Streets consist of 0.78 lane miles of 12 foot wide equivalent lanes.

                                                                                  E.   Land Use

                                                                                      11.84 acres of 0.5 to 2 dwelling units per acre urban residential

                                                                             III. Catchment Name - OC1,  Catchment 103.  Westleigh Retention Pond (wet) Inflow
                                                                                  BMP

                                                                                  A.   Area - 40.952 acres

                                                                                  B.   Population - No data
Figure 3.   Major Washington Area Watersheds


                 G/-8
                                                                                                               G7-9

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     C.   Drainage -  This  catchment has a representative slope of 195.4 feet/mile,
         63.7% served with curbs and gutters and 16.30% served by no sewers.   The
         drainage channels approximate a 127.25 feet/nile slope, and extend
         1800 feet.

     D.   Sewerage -  Drainage  area of the catchment is 83.7% separate storm sewers
         and 16.30%  no sewers.
      *
         Streets  consist  of 3.26 lane miles of 12-foot wide equivalent lanes.
         Curbs consist of 2.58  curb miles.

     E.   Land Use

         37.96 acres is 0.5 to  2 dwelling units per acre urban residential.

         2.94 acres  is Urban  Parkland or Open Space.

IV.   Catchment Name  - DC1, Catchment 004, Fairidge Roadside Swale BMP

     A.   Area - 18.77 acres

     B.   Population  - No  data

     C.   Drainage -  This  catchment has a representative slope of 227 feet/ mile,
         49.7% served with curbs and gutters and 50.83X served with swales and
         ditches.  The storm  sewers approximate a 190 feet/mile slope, and extend
         375 feet.

     D.   Sewerage -  Drainage  area of the catchment Is 100% separate storm sewers.

         Streets  consist  of 2.24 lane miles of 12 foot wide equivalent lanes.

     E.   Lane Use

         16.54 acres is 2.5 to  8 dwelling units per acre urban residential

         2.24 acres  is Urban  Institutional

V.   Catchment Name  - OC1, Catchment, Burke Ponds

     A.   Area - 18.3 acres

     B.   Population  - No  data

     C.   Drainage -  This  catchment has a representative slope of 230 feet/mile,
         100% served with curbs and gutters.  The drainage channel approximate a
         220 feet/mile slope, and extend 1260 feet.

     D.   Sewerage -  Drainage  area of the catchment is 100% separate storm sewers.

         Curbs consist of 1.52  curb miles.
     E.  Land Use

         18.3 acres is 2.5 to 8 dwelling units per acre urban  residential

VI.  Catchment Name - DC1, Catchment 106, Stedwick Detention (dry)  BMP

     A.  Area - 24.44 acres

     B.  Population - No data

     C.  Drainage - This catchment has a representative slope  of  248.2  feet/mile,
         79.67% served with curbs and gutters and 20.33%  served by  no  sewers.
         The drainage channels approximate a 227 feet/mile  slope, and  extend
         1000 feet.

     D.  Sewerage - Drainage area of the catchment is  79.67% separate  storm sewers,
         and 20.33% no sewers.

         Streets consist of 2.96  lane miles of 12 foot wide equivalent  lanes.   Curbs
         consist of 1.99 curb miles.

     E.  Land Use

         0.57 acres is 0.5 to 2 dwelling units per acre urban  residential

         20.70 acres is 2.5 to 8 dwelling units per acre  urban residential

         6.17 acres is Urban Institutional

VII. Catchment Name - DC1, Catchment 107, Lake Ridge Detention Pond (dry)  BMP

     A.  Area - 68.3 acres

     B.  Population - No data

     C.  Drainage - This catchment has a representative slope  of  420 feet/mile,
         68.26% served with curbs and gutters and 31.74%  served with no sewers.
         The storm sewers approximate a 164 feet/mile  slope, and  extend 2220 feet.

     D.  Sewerage - Drainage area of the catchment is  68.26% separate  storm sewers,
         and 31.74% no sewers

         Streets consist of 11.56 lane miles of 12 foot wide equivalent lanes.
         Curbs consist of 6.10 curb miles.

     E.  Lane Use

         Not available

VIII.  Catchment Name - DC 1, Catchment. 008, Dandridge Infiltration Irenrh BMP

     A.  Area - 1.96 acres
                                  G7-10
                                                                                                                                 (57-11

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     B.   Population - No data

     C.   Drainage - This catchment hat> a representative slope of 190.1 feet/mile.
         93.87% served with curbs and gutters and 6.12% served with swales and
         ditches.  The store sewers appruxlnate a 113 feet/mile slope, and extend
         540 feet.

     0.   Sewerage - Drainage area of Uie catchnent is 100% separate storm sewers.

         Streets consist of 0.27 lane miles of 12 foot wide equivalent lanes.   Curbs
         consist of 0.13 curb miles.

     E.   Land Use

         1.96 acres is greater than 8 dwelling units per acre urban residential

IX.   Catchment Name - OC1, Catchment 009, Rockville City Center Porous Pavement BMP

     A.   Area -4.2 acres

     B.   Population - No data

     C.   Drainage - This catcliment has a representative slope of 135 feet/mile,
         74.3% served with curbs and gutters and 25.7% served with no sewers.
         Ihe storm sewers approximate a 135 feet/mile slope, and extend 390 feet.

     I).   Sewerage - Drainage area of the catchment is 74.3% separate storm sewers,
         and 25.7% is no sewers.

         Streets consist of 1.82 lane miles of 12 foot wide equivalent lanes.   Curbs
         consist of 0.25 curb miles.

     t   land Use

         3.J2 acres is urban institutional

         l.ut) acres Is urban parkland or open space.

X.    Catchment Name - (id. Catcliment Oil, Burke Village Shopping Center Infiltra-
     tion Trench BMP

     A.   Area -4.5 acres

     B.   PupuI at ion - No data

     C.   Drainage - This catcluuent has a representative slope of 85 feet/oile,
         82% served with curbs and gutters and 18X served with no sewer.   The  stom
         sewers approximate a 30.6 feet/oile slope, and extend 585 feet.
     D.  Sewerage - Drainage area of the catchment  is 82%  separate storm sewers,
         and 18% no sewers.

         Streets consist of 2.14 lane miles of  12 foot wide equivalent lanes.   Curbs
         consist of 0.36 curb miles.
t.   Land Use
     3.69 acres is urban commercial shopping center, O.B1  acres  is urban parkland
     or open space.
                                  G7 12
                                                                                                                                 G7-13

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                                   PROBLEM
A.   Local definition (government)

In 1975, the Water Resources Planning Board (WRPB) of the Metropolitan Washington
Council of Governments (COG) was given broad responsibilities and funding support
to conduct areawide waste treatment management planning  in the Washington metropol
itan area pursuant to Section 208 of the  Federal Water Pollution Control Act of
1972.   In accordance with its mandated responsibilities, the WRPB adopted an ini-
tial 208 Waste Treatment Management Plan  for the Washington area in June 1978.
The Plan was subsequently approved by Washington area jurisdictions and is cur-
rently under review by State certifying agencies.

As a starting point for developing an understanding of pollutant sources and im-
pacts affecting Washington area waterways,  a water quality assessment was con-
ducted as part of the initial 208 plan.   This assessment identified the following
general conditions.

     •  The Potomac estuary experiences periodically excessive algal concentra-
        tions and occasional contraventions of dissolved oxygen standards during
        summer periods of low fresh water inflow and high water temperature.

     •  Ther is no longer a diversified system of bottom life in the upper Potomac
        estuary.   Nearly all rooted aquatic plants are gone from the estuarial
        shallows of the Potomac and Anacostia rivers.

     •  The recreational and commercial value of acquatic life within or dependent
        upon Potomac and Patuxent River waters has generally declined due to habi-
        tat descruction and water quality degradation.

     •  Few streams in the more urbanized portions of the Washington metropolitan
        area consistently meet bacterial  standards for safe water contact
        recreation.

     •  The recreational and aesthetic value of many of  the region's stream valley
        has decreased due to stream channel destruction  resulting from uncontrolle
        storm runoff in urbanizing areas.  This has also resulted in declines  in
        the diversity and range of acquatic and water associated species inhabitin
        these small streams.

     •  Sedimentation from excessive upstream erosion is reducing the storage  capa
        city of the Occoquan reservoir -- a major water  supply source for
        Northern Virginia.  Periodically  high suspended  solids loads in the
        Potomac River has also resulted in higher water  treatment costs for the
        Washington Suburban Sanitary Commission at its Potomac filtration plant.
     •   As the Washington area has developed, related  increases  in the amount of
        land surface made impervious to rainfall have  increased  stormwater runoff
        pollutant loads and freshwater flows to downstream  areas in periods im-
        mediately following storm events.  The combination  of  increased freshwater
        flows from runoff, and increased sediment, nutrient, and bacterial loads
        being swept down into the Potomac and Patuxent estuaries appear to have
        reduced available commercial seafood harvesting areas,  reduced fish spawn-
        ing and nursery grounds and stimulated excessive plant  and algal  growth.
        Eutrophic levels of algae production is an especially  visible problem at
        the Occoquan Reservoir.

B.   Local perception (public awareness)

The public participation program will provide the opportunity  to determine the
public perception of water resources problems.
                                  G7-14
                                                                                                                                 G7-15

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                             PROJECT! DESCRIPTION
A•   Major Objective.

I lie Washington Metropolitan Area's  Urban Runoff Demonstration Project is being
undertaken as one of 28 projects  sponsored by EPA  in various urban areas through-
out the country as part of  its Nationwide Urban Runoff Program (NURP).  The pro-
ject will provide information on  urban  uoripoint source loadings and potential
control measure effectiveness needed by EPA  in its national assessment or urban
runoff problems and potential controls.  It  will also develop local field data
needed to help assess the impacts of nonpoint loadings in Washington area waters
and to quantify the costs and effectiveness  of potential control measures.  This
work is critical to the identification  and implementation of water quality manage-
ment strategies that are based on a full understanding of interactive point/
nonpoint source loading impacts on  the  region's waters and the potential control
tradeoffs available for meeting clean water  goals  in the most cost-effective
manner.

Individual tasks being executed under this project have been designed to build upon
the land use/runoff relationships and Best Management Practice (BMP) pollutant
trap efficiency and cost information originally developed for the Washington, O.C.
recjitm as part of the Metropolitan  Washington Water Resources Planning Board's
(WRPB) initial 20d planning effort.

The specific and interrelated tasks being carried out in this project will:

     •  Document, through monitoring and analysis, the costs and effectiveness of
        alternative Best Management Practices (BHPs) for nonpoint pollution
        control.

        Related tasks will  associate BMP effectiveness with sediment particle size
        (for detention controls)  and soil absorption characteristics (for  infiltra-
        tion controls).

     •  Refine atmospheric loading  estimates and  identify air/water quality manage-
        ment interfaces and possible regional variations in air quality that should
        be accounted for in the local application of runoff data to specific geo-
        graphic areas.

     •  Demonstrate the detailed  application of  land use/runoff relationships to
         identify nonpoint source  management  program alternatives in two prototype
         local watersheds selected for further study in the  region's initial
        206 planning effort.

     •  Refine existing land use/runoff loading  estimates in central business dis-
        trict areas which have very high  levels  of  imperviousness and on-site
        activity.
        Identify the bioavailability of phosphorus loads in urban runoff and the
        presence of other toxic substances specified in EPA's list of pollutants.

        Identify maintenance and captured pollutant disposal guidelines for urban
        BHPs having potential application In the Washington area.

In addition, local technical liaison and public participation activities, under-
taken as part of overall project execution, are being used to further refine and
develop local understandings of nonpoint pollution problems, demonstrate the types
of measures currently available to control these problems, and otherwise encourage
the participation of local jurisdictions and affected Interest groups in the im-
plementation of detailed planning and nonpoint source management activities that
may be needed to meet area water quality goals and standards.

All of these activties are needed to develop an adequate understanding of the over-
all significance of nonpoint loadings and the most cost-effective means available
for their control.  Without these analyses and associated demonstration of local
data applications, it would be nost difficult to gain any meaningful degree of
local support and participation In implementing those nonpoint management programs
that may be needed to protect certain area waters.  Final task outputs will also
provide EPA with state-of-the-art planning and management tools that will be help-
ful in the evaluation of other urban nonpoint pollution problems and solutions
from the broader perspective of national needs that EPA is addressing through its
Nationwide Urban Runoff Program.

B.  Methodologies.

The Washington, O.C. NURP project will substantially refine and expand upon the
preliminary nonpoint source data base collected during the region's initial
208 water quality planning effort.   As part of its initial activities as the de-
signated agency for areawide waste treatment planning in the Washington region —
the Metropolitan Washington Water Resources Planning Board (WRPB) sponsored sev-
eral field studies to develop basic data needed to identify the major sources and
magnitude of area nonpoint pollution contributions and to evaluate the need and
options available for nonpoint control.  These studies produced estimates of land
use/runoff relationships from 11 representative land uses (7 of which were urban/
suburban in nature), and Best Management Practices (BMP) pollutant removal effi-
ciency and cost information primarily directed toward BMP applications in urban
and developing land uses areas.

Conducted for COG by the Northern Virginia Planning District Commission (NVDPDC)
and VPI & SU's Department of Engineering, the land use/runoff study analyzed rain-
fall and runoff data from over 300 site/storms collected between June 1976 and
May 1977 at 21 small watersheds in Northern Virginia.  Each composite, the moni-
tored sites represented a mix of the residential, urban and rural land uses typi-
cally found in the Washington, O.C.  area.

More recent studies by the Council  of Governments have been directed at assessing
the total annual pollutant loading (BOO, N, P) reaching the upper 50 miles of the
                                  G7-I6
                                                                                                                                67-17

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Potomac Esluary, by source, and considering both loads delivered by watersheds within
the metropolitan region and pollutant loadings originating from the Upper Potomac
Basin above the Washington, D.C.  area.  Using the NVPOC land/runoff relationships
previously cited, nonpoint loadings from the region's 42 major watersheds were
assessed based on simulations of current (1977) and forecasted (2000) average
annual total and unit area nonpoint loads for average rainfall year and according
to existing and forecasted land use patterns.  Regional versus upper Potomac Basin
loading comparisons were developed based on an analysis of US EPA and USGS data
taken at Chain Bridge (at the head of the Potomac Estuary) during the late 1970's.
Point source loadings were considered based on all permitted discharges to the
Upper Estuary and its direct tributaries below Chain Bridge.   Projected point
source discharges were calculated to reflect Implementation,  over time, of NPOJS
discharge permits.

Study Findings

These initial 208-retated studies resulted in the following conclusions regarding
urban nonpoint pollution, its impact and control In the Washington, D.C. area:

     1.   The concentration of pollutant loads in runoff fron urban sites was sig-
         nificantly higher than runoff from rural/agricultural sites on a per acre
         basis.

     2.   Urban runoff contained significant loadings of BOD,  nitrogen and phos-
         phorus on a per acre loading basis.   Runoff rate, volume and pollutant
         loadings Increased as land area increased in impervious cover (see
         Table 2).

     3.   Urban areas with a high percentage of impervious land cover generally
         shows significant, "first flush" effects for certain pollutants.

     4.   local storoiwater runoff loadings represented roughly one-half the current
         total annual pollutant loading of BOD, N and P, particularly as point
         source discharges are brought under control.

     5.   Local runoff represented approximately 20 percent of the total pollution
         load at Chain Bridge.   A majority of the load originated from sources
         (primarily nonpofnt) upstream of the Washington, D.C. area.

     6.   Local runoff and upstream nonpoint loadings, if controlled, would far
         exceed future nonpoint source loadings on an average annual basis
         (Figure 4).

     7.   Nonpoint loads from stormwater runoff and combined sewer overflow loads
         are extremely transient and variable.  Both respond directly to runoff
         produced by precipitation and snow-melt.  The generation of nonpoint
         pollutants ranges from nearly no contributions at all during dry periods
         to the largest and most Important source of pollutants during major run-
         off events.  Similarly,  combined sewer overflows typically do not occur
         unless some type of runoff Is generated, but overflows represent the most
         severe form of localized pollution when they do occur.
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                                  R7-18
                                                                                                                                    G7-19

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      8.  Uncontrolled urban stonnwater runoff volumes posed a threat to stable
          streambed habitats.

      9.  Application of certain BMPs appeared to be feasible methods of reducing
          urban runoff loads, particularly in developing areas of the region.  Of
          these. Modification of storrowater management structures to achieve added
          water quality benefits appeared particularly cost-effective.  Habitat
          protection and trapping of heavy metals were identified as additional
          benefits provided by certain BMPs.   Available data were incorporated into
          the 1980 Supplement to the region's 208 Water Quality Management Plan.

 The following is a summary of task objectives and methodologies:

 Task 1.  BMP EFFECTIVENESS STUDIES

 Runoff inflows and outflows of certain BHPs  are being monitored to determine wine
 pollutant removal efficiencies for different BMPs having potential application in
 the Washington metropolitan area.   BMP efficiency data will be used by  local and
 regional  agencies to:

      •  Address local  technical  and poll tea) concerns about the effectiveness of
        typical nonpoint pollution control measures specified in the initial
        208 plan and develop information on  the efficiency  of local BMPs  that is
        equivalent in  detail  to  the "urban  land use-nonpoint pollution"  relation-
        ships produced by the  initial  208 planning study.   The BMP efficiency data
        will be used by  local  and  regional agencies to evaluate nonpoint  pollution
        management strategies  for  the  region's  watersheds.

      •  Refine the region's  "urban land use/nonpoint  pollution"  relationships
        produced In the  initial  208 planning effort,  by  collecting and analyzing
        nonpoint pollution  loading data  from new monitoring sites  under various
        neteorologic conditions.

      •  Refine  the region's 208  "desktop" nonpoinl  source and  BMP  assessment
        models  to enhance applications by local  public works and land use planning
        staffs  using the BMP efficiency and  nonpoint pollution loading relation-
        ships  cited above.

      •  Refine  the region's 208  "computer-based" planning models to enhance  appli-
        cations by regional planning agencies Involved in water  quality management
        using the  BMP efficiency and nonpoint pollution  loading  relationships.

      •  Actively  Involve representatives from the home building  industry in  the
        evaluation of BMPs that are being considered for the region's urban  areas.

Task 2.  AMORTIZED/UNIT COST DAFA ON BMP CAPITAL MAINTENANCE AND OPERATING


Itemized unit cost information is being developed for BMPs used  throughout the
Metropolitan Washington area.  This information will allow for projection of
figure 4.   Average Animal  Pollutant  Loads
                                                                                                                G7-21

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anticipated capita) costs of BMPs  as well  as  projections of manpower and equip-
ment expenditures required to maintain  BMPs  in proper operating condition.  Data
Mill be amortized and reviewed with other  BMP test results in determining cost-
effectiveness of the various BMP alternatives.  Operating, maintenance, and pollut-
ant disposal guidelines  that are necessary to insure the continued effective
operation of these structures will also be developed.

Task 3.  SCAN OF 128 PRIORITY POLLUTANTS

While there is strong evidence Indicating  that storm runoff represents a major
contribution of contaminants to acquatic systems, the majority of work in this
area has concentrated on traditional sanitary and chemical parameters.  To assist
in its nationwide assessment of the presence, severity, and sources of 128 prior-
ity pollutants, EPA has  requested  that  a limited scan of priority pollutants in
runoff be included as part of the  NURP  project.

Runoff from representative urban land uses (including a central business district,
an Industrial site, suburban shopping center, and a nedium density residential
area is being sampled for the 128  priority pollutants Identified by EPA.

Task 4.  REFINEMENTS OF  RUNOFF DATA IN  CENTRAL BUSINESS DISTRICT (CBD) AREAS

Several years ago,- as part of its  overall  Combined Sewer Overflow Study, the D.C.
Department of Environmental Services  installed and monitored the quality of storm
runoff from two sampling stations  In  the Washington area's CBO.  At COG's sugges-
tion, the samples collected and sampling methodology were patterned after the
NVPDC/VPI&SU study to provide comparable data.  Under this task, NVPDC Is analyz-
ing the sampling data collected to refine  the original NVPDC land use/runoff rela-
tionships to specifically reflect  CBD areas.  (NVPDC's original runoff studies foY
the WRPB developed relationships for highly  impervious areas, but they were more
suburban in nature than  the CBD.)

Task S.  MONITORING AND  ANAYLS1S OF ATMOSPHERIC SOURCE CONTRIBUTION TO URBAN
         NONPOINT SOURCE LOADS

Initial 208 field work indicated that significant percentages of total nutrient
and COD loadings and lesser proportions of other constituents observed in runoff
are delivered by precipitation rather than washed off the land surface.  More ex-
tensive analysis of locatlonal differences In air quality was needed to determine
if they were substantial enough to necessitate further refinements of the land
use/runoff relationships when they are  applied to specific parts of the Washington
area.  Similarly, a better understanding of  the components and sources of atmos-
pheric loads was thought necessary to identify the most appropriate control tech-
niques and interfaces between air  and water  quality management strategies.  As an
example, data was lacking on the composition  of airborne particulates, their
source, dispersion characteristics, and the  ultimate manner in which they became
entrained in runoff (through wetfall or dustfall accumulation on the land).

This task is attempting  to quantify the contribution of atmospheric sources to
runoff pollutant loads;  consider how air-related sources should be factored into
existing land use/runoff quality relationships; assess the relative importance of
                                  67-22
atmospheric loads delivered by rainout, washout and dryfall; determine the influ-
ence of seasonal and rainfall variations on atmospheric loads; assist in  identily-
ing and quantifying possible multiple water and air quality benefits and
limitations associated with certain control techniques such as street sweeping;
and assist COG's air quality management efforts by providing a greater understand-
ing of fugitive dust sources and possible controls.

The task involves the analysis of hi-vol filter data from eight selected  state  and
local air quality monitoring stations and the establishment and analysis  of othor
data from four wetfal1/dryfall sampling sites that were constructed with  NURP
funding.

Task 6.  CONDUCT CRITICAL WATERSHED SAMPLING AND MODEL RUNS TO APPLY RUNOFF
         RELATIONSHIPS, REFINE DATA TRANSFERABILITY, AND IDENTIFY NPS MANAGE-
         MENT OPTIONS

The land use/runoff relationships developed in  initial 208 planning activities
were based upon intensive sampling of small watersheds of homogeneous land use  in
Northern Virginia.  Land uses monitored were typical of those found in other parts
of the Washington area in terms of kinds of site activity, ranges of  impervious-
ness, and underlying soil conditions.  As such, they are quite suitable  for devel-
oping preliminary estimates of overall regional nonpoint pollutant  loads  and
relative watershed contributions to these loads.  However, concerns have  been ex-
pressed that more detailed demonstrations of runoff data transferability  are
needed before such relationships are applied to more precisely defined water
quality management options and programs that may be needed for specific
watersheds.

A transferability analysis of this nature was conducted as part of  the-Occoquan
comprehensive watershed study for the WRPB.  In this study, a hydrologic  and water
quality model was set up and runoff pollutant loads were estimated  for large mixed
use drainage areas using the described  land use/ runoff relationships.   These
model outputs favorably compared with observed monitoring data once appropriate
refinements were made to reflect In-stream process effects on runoff  loads.  How-
ever, additional activity involving hydrologic modeling in conjunction with water
quality sampling and analysis was believed needed  in other watersheds of  the
metropolitan area to further demonstrate runoff data applications  in  different
areas having some variation  in physiographic and land use characteristics.

The Seneca Creek and Piscataway Creek Watersheds in Maryland were  selected as pro-
totype watersheds to further demonstrate to area local jurisdictions  the  applica-
tion of metropolitan area land use/runoff relationships  in the investigation of
nonpoint pollution problems.  The watersheds selected have mixed  land uses and
differing physiographic characteristics, and were  selected because  of their rela-
tive significance for nonpoint source  load contributions as determined through  the
WRPB's critical watershed identification process.
                                                                                                                                   G7-23

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lasfc 1.  Pl/BilC PAHIICIPATION

Ihis task contains a broad range of public participation activities geared to in-
forming and involving the public in urban runoff evaluations.   The objectives of
cespcsiie subtasfcs are as follows:

     •  To inform the public about  the problems of urban runoff, the objectives of
        the HURP project and the nature of the research conducted under NURP.

        To encourage the involvement of a broad range of interested and affected
        constituencies in BMP evaluation and in the fomulation of regional urban
        runoff policies that may be prompted by NURP project results.

     Activities include:

     •  publication of newsletters  and other literature to educate the public on
        the issues related to urban runoff and NURP studies and objectives.

     •  preparation of urban runoff exhibits, slides and other audiovisual mater-
        ial

     •  BMP site tours

        presentations to outside citizen and professional organizations

        COG Public Advisory Commit lee involvement

        media education

        conference sponsorship

these activities are being timed to parallel the NURP project's technical work and
management activities.  The initial focus has been on providing information about
the urban runoff situation in the Washington area and the objectives and method-
ology of the NURP project.   As the  project progresses and data becomes available,
more attention will be devoted to surveying the public on issues of BMP accepta-
bility, costs, effectiveness and willingness to pay.  A concluding conference in
FY '82 is to be sponsored to facilitate discussion between citizens, development
interests and public officials on possible policy and implementation approaches to
urban runoff control.

C.  Monitoring.

     1.  The BMP sites devised in Table 3 and located in Figure 5 monitored, con-
sist of three types of BMP practices as follows:

Source CuntroIs

Programs that are designed to minimise the accumulation of pollutants  on the land
surface during dry periods between  rainfall events, and subdivision site design
I
o>
                                                                                                                                   G7-25

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policies that, are directed at reducing  the potential for generating nonpoint pollu-
tants during storm events.   These programs can range from policies that encourage
the use of roadside sw.iles and other  natural drainage systems in lieu of conven-
tional connected storm drain systems, to  reducing roadway pavement widths in order
to decrease the total  amount of impervious surfaces created through development.

This type of control is being tested  at the following NURP sites established dur-
ing 1980.

     •  Fairldge (Swale Drainage and  Reducted Pavement Width)

     •  Stratton Woods (Swale Drainage)

     •  Dufief (Swale  Drainage and Reduced Pavement Widths)

Volume Controls

Volume Control BHPs obtain their pollutant removal effectiveness through channel-
ing a specific volume  of runoff, containing both dissolved and suspended pollu-
tants, into the soil profile where pollutants are trapped or otherwise degraded by
the natural checmical  and biological  processes that take place in the soil.   This
type of control Is being evaluated at the following sites during this NURP
project.

     •  Dandridge Apartment Complex (Infiltration Pits)

     •  Burke Village  Center Shopping Center (Infiltration Trenches)

     •  City Center Building (Porous  Pavement with underlying stone storage area)

Detention Controls

Detention controls obtains their pollutant removal effectiveness through detaining
captured storn runoff  for a sufficient  period of time to allow suspended pollu-
tants to settle out through the natural sedimentation process.  The pollutant re-
moval effectiveness of both "wet ponds" and "dry ponds" were evaluated during 1980.
The dry ponds that were evaluated were  equipped with modified outlet structures
designed to detain storm runoff for a period of 24 hours prior to its release to
the receiving waters.   The sites being  monitored that are equipped with detention
controls are:

     •  WesHeigh (Wet Pond)

     •  Burke Village  (Wet Pond)

     •  Stedwick (Dry  Pond)
                                  G7-26
     2.   The priority pollutant scan sites are divided  into  two sets.   Tlie  first
set consists of three paired stations:

         1.  Falridge/Stedwick;

         2.  Oufief/Westleigh; and

         3.  Burketown Center/Burke Pond.

The close arrangement of these stations allows for sampling  to take place at bnth
of the pairs during a single storm event.

The second set of sites consist of a series of individual  sampling stations.
These sites include:

         1.  Rockville City Center;

         2.  Stratton Woods;

         3.  Dandridge; and

         4.  Lakeridge.

     3.   Four wetfa)I/dryfall (WD) sampling stations have  been established  as
shown In Figure 6 within the COG area as part of this NURP program.   Ihese  sites
are located at the Burke Village Shopping Center In Burke, Virginia,  adjacent to
the BMP volume control monitoring site, with the other  being located  at the U.S.
Park Service Administrative Building in Southwest Washington, D.C.

     4.   The eight (8) hi-vol sampling stations established  as part of this NURP
project represent the widely diversified conditions found  within  this region.
Their spatial distribution throughout the metropolitan  area  also  Insures that in-
formation gained through this work will contribute to a greater understanding of
the impact air quality has on nonpoint source pollution problems.

Five of the stations have been located in the more suburban  portions  of the region.
These sites will collect total suspended particulate (TSP) data  from  the following
surburban business districts:

     Maryland

         Rockville, Montgomery County

         Laurel (Laurel Junior H.S.), Prince George's County

         Hall (C&P Telephone Co.), Prince George's County

     Virginia

         Massey Building (Police Station), Fairfax County

         Fort Belvoir  (South Post Bldge. #247), Fairfax County
                                                                                                                                  67-27

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                                                          MM MUMTITI CP
Figure 6.   Location of Wetf»11/Dryfal 1 Monitoring Sites
                           G7-28
The remaining three sites are located in more dense urban areas of the metropoli-
tan region.   They are located as follows:

     District of Columbia

         Catholic university, Northeast D.C.

         lladley Hospital, Southeast O.C.

     Virginia

         Aurora Hills Community Center, Arlington County

The distribution of these TSP sampling station allows for conclusions to be drawn
regarding the variations in air quality that exist betwen the high density busi-
ness districts and lower density suburban developments.   Figure 7 illustrates this
regional distribution of TSP Hi-Vol sampling equipment.

     5.  Two watersheds are being monitored as shown in Figure 8.

Seneca Creek

The Seneca Creek watershed is located in Central Montgomery County, Maryland and
drains an area of approximately 82,440 acres,  (his watershed is located almost
completely within the Piedmont Plateau, an area characterized by gently to steeply
rolling topography.  Elevations within this area range from 850 ft. Mean Sea Level
Datum (MSI) in the northeastern section to 180 ft MSL at the mouth of Seneca Creek
at its confluence with the Potomoac River.

Soils found within the Seneca drainage area are typical of those common to the
Piedmont Plateau, having been derived, in part, from the underlying igneous,
metamorphic and older sedimentary bedrock.   Approximately 45 percent of these
soils belong to the Glenelg-Hanor and Chester associations.  These are well
drained silt loan soils that produce moerate to low amounts of runoff in their
undisturbed condition.  The next largest group of soils (30 percent) are from the
Manor-Linganore-Glenelg association.  These are also silt loam soils that produce
moderate to low amounts of runoff.   The last major type of soils (20 percent)
found within the area are the Penn and Lewisberry Association that developed from
the Triassic sandstone common to the area.   These are silt loam (Penn) and sandy
loam (tewisberry) soils that generate moderate to high amounts of runoff in their
undisturbed condition.

At the present time, the Seneca Creek Watershed is primarily rural in character.
This situation is expected to change considerably during the next 20 years, how-
ever.  This transformation will include conversion of extensive areas into single
family and other types of residential housing, as well as the more intensive com-
mercial uses.  This activity is summarized in Table 4.3.

The results of the NURP critical watershed monitoring will be used to establish
and calibrate the Hydrologic Simulation Program-Fortran (HSP-F) continuous simu-
lation water quality node! under existing land use conditions.  Following the
calibration of this model, the project land use changes will be inputed.   From
                                                                                                                         G7-29

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KEY
  Lautlon at Ht-Vol Supllng

  SuUoo*
                   Figure 7.   Location of Hi-Vol Supllng  Stations
                                                                                                              Seneca Creek
                                                                                                                Watershed
Plscatawayjyeek
   Watershed
                                                                                                                  Figure  6.   NURP Watershed Study Areas and Monitoring Sites
                                         67-30
                                                                                                                                         G7-31

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these ciiamjtb, the impact of development on water quality within I he basin can be
evaluated.  The results from this study will also allow other jurisdictions with
similar physiographic situations to better estimate the impact that extensive
changes in land use will have on water quality within their area.   In addition
this study will provide EPA with a documented working water quality/ land use
planning tool.

pibcataway Cruuk

ihc- Piscaldway Creek Watershed is located within the southwestern portion of
Prince George's County, Maryland.  In contrast to the Seneca area, the Piscataway
Watershed is  located within the Atlantic Coastal Plain physiographic province.
This area is underlain by the unconsolidated deposits of gravel, sand, silt and
clay and characterized by gently rolling hills dissected by broad shallow valleys.
Elevations within the watershed range from approximately 260 ft HSL in the north-
east portion to sea level at the entrance of Piscataway Creek on the Potomac
Estuary.

The majority (53 percent) of the soils found within the drainage area are from the
Sassafras Cruoa Association.  These are gravelly loam and sandy loan soils that
produce low to moderately high amount of runoff in response to rainfall.   The
second largest group of soils found within the watershed (33 percent) consist of
the Beltsville-lfeonardtown-Chillum Association.  These are silt loam soils that
are generally found in the upland portions of the watershed, which because of com-
pact subsoils and substratum layers, generally produce moderately high to high
amounts of runnoff.   The last major group of soils found within the watershed
(13 percent) consist of those formed within the tidal marsh and floodplain areas
adjacent to the major stream channels of the watershed and the Potomac Estuary.
These soils are extremely variable in their characteristics, due to their loca-
tion, and range from poorly drained to well drained with all subject to some de-
gree of periodic inundation due to flooding.

Even though the Piscalaway watershed will not undergo the dramatic changes in ur-
banization that are expected in the Seneca Watershed, available information indi-
cates that the area will undergo a significant amount of growth during the next
20 years.

0.  Equipment

All of the monitoring stations have been designed with equipment being selected to
allow maximum flexibility in installation.   See Figure 9 for schematic.   A brief
explanation of the function of each piece of station equipment and its role in the
overall station operation follows.

Rain Gaging Equipment

A tipping bucket rain gage with a sensitivity of O.OJ" of rainfall was selected
for use with voltage accumulator devices.  The voltage accumulators count the num-
ber of bucket tips (and therefore the amount of rain) and convert the number into
a voltdge.  The voltage created varies from 0-5 vdc.   Each increase of 5  mv signi-
fies 0.01" of rainfall.   The voltage is constantly maintained, so that whenever a
recording device (such as a data logger) queries the accumulator,  the total pre-
cipitation to the moment nay be determined.
                                  U7-J2

s
                                                                                                                                 G7-33

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Primary Flow Measuring Devices

In most cases,  a primary  flow measuring device was installed at each monitoring
location.   This primary device  is  used to  facilitate the development of a stage-
discharge relationship and consists of some  type of flume.  The two types of
flumes utilized are "Palmer-Bowlus" and Type H."  Where possible, the "H" type
flume was perferred because of  its wide range of flow measurement, ability to
function while  submerged,  and ease of installation.

Secondary Flow  Measuring  Device

A bubbler-type  secondary  device was selected for use during this study.  The in-
strument makes  use of pressurized  gas and  a  transducer arrangement to measure
static head.  A microprocessor  arrangement then allows for the conversion of sta-
tic head data directly into flow rate by using the stage-discharge relationship of
the primary measuring device.   This flowmeter is also the basic controller of the
station in that it activates the sampling  device at predetermined equal increments
of total flow.   In addition, the device outputs a 4-20 ma analog signal propor-
tional to the flowrate.   At times  of sampler activation, the flowmeter also momen-
tarily activates the data logger,  which then scans all the appropriate data
channels.

Automatic Samplers

The sampling units utilized in  this study  are all portable, automatically acti-
vated 12 vdc battery powered devices.  These units are activated by the secondary
flow measuring  device during periods of flow and are capable of retrieving a
500 ml. sample  against a  suction  lift of 20  feet using a 3/8" hose of 25 ft. long.
Each sample is  withdrawn  at a velocity of  3  feet per second up to 15 ft. of suc-
tion head.  Each unit has the capability of  collecting either discrete of compo-
site samples.  These samples are then collected in either a 24 1.0 liter capacity
container or a  single 15.0 liter polyproplyene bottle depending on the needs of
the site.

When discrete samplers are collected, each unit can collect up to four (4) samples
of equal volume per bottle and  distribute  a  single sample among as many as four
(4) bottles.   Upon activation,  the sample  collection unit purges the sample line
to prevent contamination  both before and after the collection cycle.

Data Logger

A cassette type data logger is  attached to the rain gage accumulator and flow-
meter.  An Internal quartz crystal clock allows data from all associated Instru-
ments to be recorded on the same time base,  thus eliminating the timing error
problems that plague the  acquisition of synoptic hydrologic data.  The logger
scans flowmeter and rain  gage channels  at  regularly selected switch Intervals and
when the sampler is activated.

Power Unit

Each station is powered by a single deep-cycle 12 vdc battery.  This unit is
changed at a minimum Interval of one week, or whenever station power demands make
it imperative.
                                  G7-34
Wetfall/Dryfall Sampling Station Instrumentation

The wetfall/dryfall (WO) sampling stations have been equipped with  table  mounted,
12 vdc battery operated units that collect material that  Is deposited  under both
dry and wet meteorological conditions.  This  is accomplished by having one of the
two sample collection units of equal cross sectional area exposed to the  atmos-
phere.  Upon sensing the onset of precipitation,  the device automatically closes
the dryfall collector to the atmosphere and exposes the wetfall side.   Upon sens-
ing the end of precipitation, the sequence is  reversed.   Samples are then removed
to the lab for analysis.

Watershed Monitoring Site Instrumentation

With the exception of the primary flow measuring  gages, the equipment  deployed at
the two critical watershed monitoring sites are identical to those  used at the BMP
sites.  Since both of the critical watershed  stations  are located at existing USGS
flow recording gage sites, it was decided to  utilize the  inplace controlled stream
cross sections as the primary measuring device.   While USGS had no  objection to
allowing Installation of this equipment in their  gage  houses (space permitting),
they were unwilling to provide nonagency personnel with direct access  to  their ir-
replaceable flow records.  This required that  the procedure described  below be
implemented at each site.

Seneca Creek

The secondary recording device is connected directly to the existing USGS stage
recording "stilling well."  A magnetic reed switch arrangement was  then installed
on the "Stevens" recorder that allows the water quality sampler to  be  triggered at
each 0.25 ft. Interval of rising or  falling stage.  This  procedure  produces se-
quentially collected discrete samples which may then be flow-composited by hand.
The actual sampler intake hoses are  placed In the main stream channel.

Piscataway Creek

Due to space limitations in the existing gage housing, the monitoring  equipment at
this site is contained  in a pad mounted fibergalss protective enclosure adjacent.
to the USGS structure.  The flowraeter bubbler tube is  then anchored inside the
existing gage house near the USGS datum.  The sample uptake probe was  then estab-
lished within the main  stream.  An Erasable Programmable  Read Only  Memory (EPROPM)
is then used to store data from the  flowmeter used at  the station.  Flow weighted
composite samples are then collected using this arrangement.

D.  Controls

The BMP controls evaluated are source controls, volume controls, and determination
controls as described in Table 3.
                                                                                                                                  67-35

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                         TABLE 3.   FIXED  SITE  CHARACTERISTICS OF  BMP  MONITORING SITES
NOJHTOtllK
IMI
MU I DENSITY
iwrtll ftml/ACM)
•Saa^BS-^^lww?1
m*r \ "VrnVmn LinSKfRnn
E*|l OP CATCMMnr AIU
;. tMsc-ior sinciE fnxitt RCSIDCHTIAL
A. Strttton Hoods
1. Olfltf
C. HtstUloh Inflow:
Onflow:

A. ftlrloot
8. BurW Ponds Inflow:
Out (ION:

A. StxHIck* Inflow:
Outdo*:
B. Ltlwrtdot Inflow:
Outflow:
C. Omdrtdo.

A. DodKlllt City
C*nttr

A. Bulk Mill Inflow:
Cmur ' Outflow:
8.b 1.8
11.8 2.2
40.9 1.2
47.9

18.8 2.8
18.3 1.0
27.1

27.4 6.1
34.4
68.3 ».0
88.4
2.0 56.0

4.2 I/A

19.0 «/A
20. 1 «/«
».2
18.5
21.2
il.7
11.
14.1
32.7
30.1

13.8
30.5
a.t
x.o
M.4

M.S

83.0
78.5
16.5
11.1
14.0
13.7
orttsod —
nxlt
grasMd —
suit
Mt 191.400
pond
— 100 0
— 100 0
Surf in Am: 100 83.70
35.500 to. ft.
0
0
14.30
KOUM DEIISin SIHEIE FWIIT BtSIOtHIIAl
21.0
n.i
21.1
III.
22.1
19.:
27.2
24.0
34.0

. C9.S

83.0
78.5
grnstd .—
SMlt
«.t 135.000
— 100 0
Smf Mt Am: 100 100
41.400 so. ft.
0
0
TOWOBUSt/WRDCB »PMT«KT!
dry 38.000
pond (HTSI
5.5' It* rlitr 100 79.<7
dry 210.000 7.5' rlttr 100 68.JS
pond (10 yr/2nrl
Inflltrt- 4.060 Perfonttd 6* 100 100
tlon pits (mid tll» dnim
sptcv)
II. OFFICE

poraol 27.400 PtrforttM 6* 100 74. »
pwomt (mid dnln
iptnl
«. IIOUSniAl
dry 68.000
pond (UPS)

l.S- 8' t\m. 100 •
rtstr
20.13
31.74
0

25.70

•
•i. swrim CUTEI
A. Burti *ll)iot
Shopplnt Cnur
4.S "/»
71.2
79.2
Inflltrt- 11.240 —
tlon pits (ootd
sptc*)

*SI«d»lck Mi HMD •odl'IM no (unction u • Or arf pond  (M< fotxm «ft«ttliio the ml taring iltn » tM «M of Soctlon If for • cowltu dlicnulo
 of mMflutloin).

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 NATIONWIDE URBAN RUNOFF PROGRAM
JONES FALLS URBAN RUNOFF PROJECT
       BALTIMORE, MARYLAND
    Regional Planning Council

       In Association With

         Baltimore City
        Baltimore County

            and the

    U. S. Geological Survey

        •REGION III, EPA

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                                 INTRODUCTION
                                                                                                                            PHYSICAL DESCRIPTION
In over 375 years, the Baltimore metropolitan area has developed into one of
the nation's largest urban centers.   This growlh,  spawned primarily by commercial
and industrial interests centered upon maritime activities, has been a majot-
factor of the degradation in quality of the surrounding waters.  The region's seven
major watersheds provide rapidly flowing freshwater  to numerous estuarine
ranbayraents which drain into the Chesapeake Bay, the  nation's  largest estuary.
The Bay supports an abundance of finfish and shellfish populations which repre-
sent a considerable economic resource to the states  of Maryland and Virginia.
This delicate ecosystem also represents a major artery of water-borne transporta-
tion and a recreational resource of  virtually unlimited potential.

Historically, local streams have enjoyed a multitude of uses  including drinking
water supply, commercial and public  fishing, spawning grounds for certain species,
boating, swimming, agricultural support, industrial  consumption, and the transporta-
tion of wastewater discharges.  Many of these uses have suffered due to the severe
degradation of water quality.  Numerous problems have been  identified, including
the following:  extensive land surface and streambank erosion resulting in sedi-
ment which  fills water supply impoundments and adversely  affects aquatic species;
entranced algal propagation with resulting eutrophication  in freshwater impoundments
and estuarine embayments; and, potentially adverse health effects due to bacterial
contamination.

Although less than one-third of the  region is considered  to be urbanized, urban
stormwater runoff has been identified as a significant factor in the degradation
of local receiving waters.  The Jones Falls Watershed, selected because of.its
representative urban/urbanizing characteristics, provides an  excellent case study
of urban runoff - its sources, causes, impacts, and  cost-effective control mea-
sures.  More specifically, the Jones Falls Urban Runoff Project (JHURP) is de-
signed  to identify and quantify all  significant sources of  pollutants in the
watershed, define the existing water problem(s), and examine  selected management
practices capable of "cost-effectively" controlling  the  identified  problem(s).

Cooperation among the region's six local jurisdictions  in successfully formulating
and implementing the Areawide Water Quality Management Program has provided a
unique  framework for JFURP.  Project coordination and technical guidance is vested
in the  regional forum - the Regional Planning Council (RPC).   In  light of the fact
that the study watershed is located in both Baltimore City  and Baltimore County,
the participation of these jurisdictions was desirable and  has been  guaranteed.
Past successes in water quality management within the Baltimore Region have been
assisted by direct  involvement of this nature.  The  II. S. Geological Survey, an
agency  with a solid foundation of knowledge  in local and  national  hydrology, was
asked to provide technical expertise and resources to  the Project;  this assistance
is provided nationally through a formal coordination plan with the I). S. EPA and
locally by cooperative agreement.  This cooperative  effort  has greatly eased the
identification of critical issues and priorities through  an effective planning and
management  structure.
 A.   Area

     The Baltimore metropolitan region is an area of approximately 2.20O square
     miles.   The area is situated in east central Maryland to the west of the
     Chesapeake Bay and approximately 4O miles northeast of Washington, D. C.
     The urbanized portion of the region is 589 square miles (2635 of total area).
     The principal,  highly developed urban areas are located near the Bay in five
     of  the  region's seven major river basins.  Much of the older, more intensive
     urban land use is located in the Patapsco River Basin which also includes
     the Jones  Falls Watershed with an area of approximately 54 square miles.
     Figure  1  illustrates the Baltimore metropolitan area and the Jones Falls
     Watershed.

     The area  lies within the Piedmont and Coastal Plain geologic formations.
     The region receives,  on  the average, 45 inches of precipitation a year
     occurring  primarily as rainfall.   Precipitation volumes are distributed
     evenly  throughout the year but generally follow a well-defined seasonal pat-
     tern:   extended,  low intensity frontal storms during winter and spring months
     and short duration,  high intensity convective storms.

B.   Population

     The  Baltimore region  has a current population of approximately 2.2 million
     (190O).  Two-thirds of the total  are located in Baltimore  City and County.
     Development  in  recent decades  denotes a trend from the more established
     urban areas  toward  the rural countryside.   This trend continues although
     some reinvestment and  relocation  back to older urban areas has begun.   Of
     the  total developed  land in the  region,  44% is residential, indicating the
     level of land consumption for living.
    There are seven major river basins in  the region,  comprised of hundreds of
    tributaries.  These streams are generally small, shallow,  and rapidly flowing,
    draining a few miles into estuarine embayments.  Developed areas of the region
    include a mixture of natural and man-made storm drainage systems.
D.
    The urban area is primarily served by separate sanitary and  storm sewer
    systems.  Typical storm sewer systems include curbs,  gutters,  and inlets.   A
    few isolated areas of Baltimore City were developed privately  and have a
    combined sewer system; these were later assumed by the  City.   Due to the age
    of the system and rapid growth in the upstream sections, some  sanitary sewers
    have been found to leak and capacity-exceeded problems  such as sanitary over-
    flows now occur.  There is also evidence of illegal sanitary connections to
    the storm sewer system.  Present 2O1 studies are directed at correcting these
    problems.
                                    G8-2
                                                                                                                                  G8-3

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FIGURE 1 - HIE BALTIMORE METROPOLITAN AREA
           AND JONES FALLS WATERSHED
                                                                                                          PROJECT AREA
                                                                           1.  Catchment Name - WD1,  Jones Falls Watershed
                                                                               The Jones Falls Watershed  is  approximately 54 square miles,  and includes
                                                                               all of the listed catchments.   Figure  2 provides detailed illustration of
                                                                               the study area.
                                                                              A.   Area  - 34.501 acres
                                                                              B.   Population - Not yet compiled
                                                                              C.   Drainage - Subsurface and surface conveyance  to  the Jones Falls.
                                                                                   More  specific hydrologic information to be provided later.
                                                                              D.  Sewerage - Not compiled
                                                                              E.  Land Use
                                                                                  Urban
                                                                                  - Residential
                                                                                  - Commercial
                                                                                  - Industrial
                                                                                  - Institutional
                                                                                  - Expressways
                                                                                  - Cemetary/Recreational
                                                                                  •f Total Urban
                                                                                  Non-urban
                                                                                  - Agriculture
                                                                                  - Brush/Grass
                                                                                  - Woodlands
                                                                                  - Reservoir
                                                                                  - Quarry/Landfill
                                                                                  + Total Non-urban
                             Total Acreage

                                15,082
                                 1,586
                                   825
                                 1,452
                                   46)
                                 1,955
                                21,361

                                 4,192
                                 1,059
                                 7,672
                                   155
                                   142
                                                                                                              13,220
                                                                         II.  Catchment Mane - MD 1,  O08,  Lake Roland
% of Total Drainage Area

           44
            5
            2
            4
            1
            6
           62

           12
            3
           22
           .4
           .4
           38
The Lake Roland catchment area comprises the upper Jones Falls Watershed and
is approximately 35 square miles.
A.  Area - 22,142 areas
B.  Population - ftot yet compiled
C.  Drainage - Subsurface and surface conveyance to the Jones Falls and
    Lake Roland.  Representative slope of overall drainage basin is 63.32
    feel per mile.
                                   68-5
                 G8-4

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          -LEGENO-
•  RECEIVING WATERS STATION
O  SMALL HOMOGENEOUS CATCHMENT
A  AID DEPOSITION STATION
O  SUPPLEMENTAL RA1NGAGE
FIGURE 2 - JONES FALLS WATtliSHEO
           ANU SAMH-ING STATION
           LOCATIONS
                                                                                               D.  Sewerage - Not yet compiled
                                                                                               E.  Land Use                 Total Acreage
                                                                                                   Urban
                                                                                                   - Residential                7,846
                                                                                                   - Commercial                   428
                                                                                                   - industrial                   212
                                                                                                   - Institutional                831
                                                                                                   - Expressways                  276
                                                                                                   - Cemetary/Recreational        843
                                                                                                   Total urban                 1O,436
                                                                                                   Non-urban
                                                                                                   - Agriculture                4,192
                                                                                                   - Urush/Grass                  732
                                                                                                   - Woodlands                  6,575
                                                                                                   - Reservoir                     92
                                                                                                   - Quarry/Landfill              115
                                                                                                   Total Non-urban
                                                               of Total Drainage Area

                                                                          36
                                                                           2
                                                                           1
                                                                           4
                                                                           1
                                                                           4
                                                                          47

                                                                         110
                                                                           3
                                                                          30
                                                                          .4
                                                                          .5
                                                                          53
                                       11,706
          Percent of impervious area not compiled.
III.  Catchment Name - MD1, O07, Stony Run
       The Stony Run catchment area  is  a  subwatershed within the Jones Falls
      Watershed and is approximately 3.2 square miles.  Two of the snail homo-
      geneous catchments,  Homeland  and Hampden, are located within this area.
      A.  Area - 2,047 acres
      B.  Population - Estimate:  51,151 persons based on 12 persons per acre
      C.  Drainage - Subsurface conveyance to Stony Run,  a tributary of the Jones
          Falls.   Representative slope of overall drainage basin is 130.38 feet
          per mile.
      D.  Sewerage - Drainage area of catchment  is  1OGK separate storm sewer.
                                                                                                                                 G8-7
                               G8-6  .

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E. Land Use Total Acreage
Urban
- Residential
- Conrnercial
- Industrial
- Institutional
- Expressways
- Cemetary/Recreutional
Total Urban
Non-urban
- Agriculture
- Brush/Grass
- Woodlands
- Reservoir
- Quarry/Landfill
Total Non-urban

1,472
95
O
172
O
118
1,857

O
83
101
6
0
190
% of Total Drainage Area

72
5
0
8
O
6
91

O
4
5
.3
0
9
E. Land Use Total Acreage
Urban
- Residential
- Commercial
- Industrial
- Institutional
- (Expressways
- Cemetary/Recreational
Total Urban
Non-urban
- Agriculture
- Brush/Graos
- Woodlands
- Reservoir
- Quarry/Landfill
Total Non-urban

14,797
1,425
744
1,407
442
1,943
20, 758

4,192
1,059
7,672
155
142
13,220
% of Total Draic

44
4
2
4
1
6
61

12
3
23
.5
.4
39
         Percent of impervious  area not compiled.

IV.   Catchment Maine - MD1,  OO6,  Biddle Street

     Tho Biddle Street catchment area includes all of the listed catchment areas
     and is approximately 53 square miles.   This  is the lowest point of sample
     collection in the Jones Falls Watershed.

     A.   Area - 33,978 acres

     0.   Population - Not yet compiled

     C.   Drainage - Subsurface conveyance to the Jones Falls.  Representative
         slope of overall drainage basin  is 62.4 feet per mile.

     D.   Sewerage - Percent of drainage area served by separate storm sewers
         is not yet compiled.
        Percent of impervious area not compiled.

    There are five email homogeneous catchments:  Reservoir Hill, llampden,
    Mt. Washington, Bolton Hill, and Homeland.  These areas are located within
    the Jones Falls Watershed and range in size from 1O to 23 acres.  The areas
    are predominantly residential.

V.  Catchment Name - IO1.  CO1, Reservoir Hill

    A.  Area - 10.42 acres

    B.  Population - 577 persons

    C.  Drainage - Subsurface conveyance to the Jones Falls.  Main channel is
        437 feet at a slope of approximately 1O2.7 feet per mile.

    D.  Sewerage - Drainage area of catchment is 1COS4 separate storm sewers.
        luCK is served by curbs and gutters.

    E.  Land Use

        - Residential
          ^ High (9 more more du/ac) = 1O.42 acres, 10CK of total drainage
            area.
                                      G8-8
                                                                                                                                     Gft-9

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  VI.  Catchment Name - MD1, OO2, llampden

       A.  Area - 17.02 acres

       0.  Population - 681 persons

       C.  Drainage - Subsurface conveyance to the Jones Falls.  Main  channel
           is 8/5 feet at a slope of approximately 274.56 feet per mile.

       0.  Sewerage - Drainage area of catchment is 100% separate storm sewer.
           100% is served by curbs and gutters.

       E.  Land Use

           - Residential

             + High (9 or more du/ac) = 12.27 acres, 72* of total drainage  area.

           - Commercial = 4.75 acres, 28K of total drainage area

 VII.  Catchment Name -MD1. 003, Mt. Washington

       A.  Area - 16.5U acres

       B.  Population - 195 persons

       C.  Drainage - Subsurface conveyance tu Western Run a tributary of the
           Jones Falls.  Main channel is 825 feet at a slope of  approximately
           355.2 feet per mile.

       D.  Sewerage - Drainage area of catchment is 100K separate storm sewers.
           87% is served by curbs and gutters and 13% is served  by swales and
           ditches.

       E.  Land Use

           - Residential

             + Medium (3 to 8 du/ac) =  13.91 acres, 84% of total drainage area.

           - Recreational = 2.67 acres,  16% of total drainage area.

VIII.. Catchment Name - MD1, OO4, Bolton Hill

       A.  Area - 14.02 acres

       B.  Population - 415 persons

       C.  Drainage - Subsurface conveyance to the Jones Falls.  Main  channel
           is 688 feet at a slope of approximately 53.72 feet per mile.

       0.  Sewerage - Drainage area of catchment is 100% separate storm sewers.
           100K is served by curb and gutter.
                                        G8-10
     E.  Land Use
         - Residential
           -f High (more than 9 du/ac) = 13.2b acres, 95% of  total  drainage
             area
         - Recreational = .73 acres, 5% of total drainage area.

IX.  Catclmient Name - MD1, OO5, Homeland

     A.  Area - 23.O3 acres

     B.  Population - 2O4 persons

     C.  Drainage - Subsurface conveyance to Stony Run a tributary of the
         Jones Falls.  Main channel is 35O feet at a slope of  approximately
         181.02 feet per mile.

     D.  Sewerage - Drainage area of catchment is 10O/6 separate  storm sewers.
         tOOH is served by curb and gutter.

     E.  Land Use

         - Residential
           + Low ('/> to 2 du/ac) = 23.03 acres, 10OS4 of  total drainage area.
                                                                                                                                          G8-11

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                                    PROBLEM


A.  Local Definition (Government)

    Section 2O8 of the Federal  Water Pollution Control  Act  Amendments of 1972
    addressed areawide waste treatment  management  planning, designating certain
    local and regional government  agencies to plan for  improved water quality
    while concurrently reviewing environmental,  land  use and organizational issues
    related to solving water quality problems in their  respective areas.  The six
    member jurisdictions of the Regional  Planning  Council (KPC), through the
    Baltimore Region's Areawide Water Quality Management Process, reported that
    urban runoff was a major contributor  of pollutants  to local receiving waters.
    Following Federal guidelines,  a water quality  management plan was adopted by
    the six member jurisdictions,  establishing an  implementation process to pre-
    vent, reduce, and eliminate sources of contamination of regional waters.

    The 2O8 Plan identified the Jones Falls as one of the most severely degraded
    streams in the region.   This stream is representative of the variety of water
    quality conditions found throughout the region.   Emanating from springs in
    Baltimore County, the Jones Falls meanders toward the south into an old, man-
    made water supply impoundment  located near the City/County jurisdictional
    boundary.   Upper watershed  streams  have been designated by the State of
    Maryland as suitable for the support  of trout  population growth and propaga-
    tion and related food sources.   This  designation  represents the most stringent
    of the State's four receiving  waters  classifications, which include the fol-
    lowing:  contact recreation and aquatic life waters, shellfish harvesting
    waters; natural  trout waters;  and,  recreational trout waters.  In spite of the
    encroachment cf  the urban area,  slowed somewhat by  local government inter-
    vention, local fishermen report that  certain upper  Jones Falls tributaries do
    indeed support a trout  population.

    Lake Roland is an almost eO-acre impoundment completed  in 18C1 to serve as
    Baltimore's first major water  supply  reservoir.   This lake suffers from a
    variety of problems, which  include  the following:  exponential sedimenta-
    tion and the resulting  loss of storage capacity;  eutrophication; and, vio-
    lations of state bacterial  standards.  The Lake Roland Clean Lakes Project,
    sponsored under Section 314 of the  Act, is currently investigating the lake's
    problems and attempting to  identify potential  solutions to restore and
    maintain beneficial uses associated with recreation.

    After exiting Lake Roland,  the Jones  Falls  continues to flow southward,
    passing through  Baltimore City  into a large conveyance tunnel and finally
    emptying into Baltimore Harbor,  the estuarine  section of the Patapsco River.
    The State  has recently  reclassified this  section  of the stream to a Class III
    receiving  water,  capable of supporting adult trout  for put-and-take fishing.
    Since 1979,  rainbow trout have  been stocked  in the upper reaches of  this
    section of the stream;  results  of this effort are not yet apparent.

    The section  of the Jones Falls  below  Lake Roland  is also the most Influenced
    by urbanization  and the  associated  pollutant sources.  These include NPDES
    discharges from  industrial/commercial  userr., sanitary sewer overflows,  illegal
    connections,  and  increased  runoff volumes due to  impervious areas.
                                     G8-12
    To recover and mintain designated beneficial uses, the State has promulgated
    water quality standards including a range of physical chemical parameters.
    The two parameters with major violations of state standards are  turbidity
    and bacteria - turbidity being storm-related and bacteria in a range of stream
    conditions.

    Storm wash-off results from selected land uses indicate signfleant levels of
    nonpoint pollution entering the receiving streams in the watershed.  The
    direct impacts upon receiving streams and relative magnitude comparisons to
    other poiiulant sources have not been established.  Also, the existing levels
    of urban housekeeping management practices being implemented by  local
    governments focus upon aesthetic and primary public health objectives rather
    than water quality.  The effectiveness of these non-structural controls aimed
    at reducing the magnitude of source-related pollutants is not known.  The pri-
    mary question is how effective are current levels of urban housekeeping in
    pollutant removal in comparison to alternative strategies, and what is the
    relative cost-effectiveness of the control applications for achievement of
    water quality objectives.

B.  Public Perception (Public Awareness)

    The assessment of public perception of water quality benefits and problems
    in a stream or lake requires careful investigation.   In the planning of JFIIRP,
    a vigorous public participation strategy was developed in recognition of the
    fact that there is a wide range of diversity in the "public" and perhaps many
    perceptions of benefits and problems.   JFURP intends to provide guidelines to
    determine how the public perceives of  local water quality problems.   In each
    of the land use categories being examined,  public lifestyles and, therefore,
    public perception and expectations of  water quality will be different.  For
    example,  citizens in heavily urbanized downtown Baltimore probably will not
    have an interest in,  or awareness of,  their impact upon downstream estuaries.
    Inhabitants of rural  areas,  on the other hand,  may be seriously concerned
    about their impact upon local  bodies of water and interested in assuming an
    aggressive posture when addressing water quality issues.

    In reviewing water quality management  strategies, these and other differences
    must be taken into account.  A first step will  include citizen surveys in each
    of the land use areas under scrutiny to determine how they perceive  local water
    quality management programs and what level  of control  they consider  necessary.
    Moreover,  citizens must be informed of the  significant economic realities asso-
    ciated with specific  management strategies.   In the  end,  public value judgements
    will  tie balanced  against  realities of  economics,  politics,  and technical  de-
    cisions and limitations.

    Examples  of efforts inspired by individuals and public and private organizations
    to revitalize areas in Baltimore adjacent to the Jones Falls and other re-
    ceiving waters include the following:

    1.  A massive urban renewal  campaign encouraged by the  City and private
        groups to rebuild local  communities and  the Inner Harbor in the
        vicinity of the Jones  Fails outflow.
                                                                                                                                    C8-13

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2.  Strong local community  interest in neighborhood "cleanliness" and
    nearby streams via clean-up campaigns, stream 'Vjatchdogs", and other
    actions.

3.  Independent stream monitoring and revilalization programs sponsored
    by organizations staffed  primarily by volunteers.

4.  Increased use of various  streams and surrounding valleys by commu-
    nity children, joggers, hikers, and other public groups.

5.  The development of far-reaching water quality public advisory com-
    mittees operating in local jurisdictions and at the regional level to
    encourage citizen awareness and education, and provide for forums for
    the elucidation of various viewpoints.

In brief, the public awareness of JFURP and the existence of urban runoff
is not only desirable, but  essential,  the public response to questions
posed about water quality "problems" in the Jones Falls will be encouraged.

Project findings, conclusions, and resulting technology gained from moni-
toring and data analysis will be disseminated by reports and a series of
technical transfer sessions.  These and other actions should provide the
basis for future inclusion  of urban runoff problem assessment and de-
velopment of control strategies in the Baltimore region's water quality
management activities.
                                                                                                                        PROJECT INSCRIPTION
A.  Major Objectives

    There is abundant evidence that the Jones Falls Watershed is plagued by
    the ravages of nature and the myriad degradations exercised by anthro-
    pogenic activities.  Identified sources of water quality impairment
    include the following:  urban runoff, sanitary sewer overflows, sediment
    releases, streambank erosion, upstream pollutant loadings, unsewered
    areas and illegal storm sewer connections.  The review of specific pro-
    blems, as identified in the "PROBLEM" section of this summary, resulted in
    the development of JFURP objectives based upon local concerns and the pri-
    mary objectives stated by EPA.  In brief, the JFURP objectives are as fol-
    lows:

    1.  Investigate and define water quality contaminants, sources, transport
        mechanisms, and receiving water impacts in the urbanized Jones Falls
        Watershed.

    2.  Quantitatively define the total pollutant contributions of the Jones
        Falls Watershed to the Baltimore Harbor.

    3.  Identify and assess the sources and transport mechanisms from a va-
        riety of small, relatively homogeneous land uses in a stable urban
        watershed and determine their comparability with similar areas in
        the Eastern United States.

    4.  Determine the efficacy of existing source control management practices
        and operational implementation strategies in the reduction and/or pre-
        vention of water quality degradation.

    5.  Determine the efficacy of Lake Roland as a water quality/quantity
        management practice and its role in water resources management,
        especially for downstream control.

    6.  Provide information supporting the development of an integrated, cost-
        effective water quality management program for the urbanized Jones
        Falls Watershed through the "2O8" Program.

    7.  Provide a basis for transfer of project findings to the related techni-
        cal public and private communities for future stcrmwater runoff manage-
        ment planning and implementation.

    Additional work will include local technical liaison and public participa-
    tion activities.  The combination of efforts should result in a mechanism
    for balanced decision-making.  Data collected throughout the Project should
    provide an illumination of choices which rest upon scientific evidence.
    Subsequent clarification of the cost-effectiveness of the control techniques
    and strategies becomes an input necessary to provide a management structure
    which includes the considerable realities of economic limitations.
                                 G8-14
                                                                                                                                G8-15

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B.  Methodology and Associated  Monitoring

    Deficiencies in knowledge demand  that a methodology be developed pro-
    viding a structure  for  obtaining  the information required to explain the
    issues confronting  decision-makers.  With problems and objectives now de-
    fined, a range  of techniques  is selected, designed to reduce the existing
    state of scientific uncertainty within resource limitations.

    Briefly stated,  the Project intends to quantify the various Inputs to the
    lower Jones Falls Watershed and assess their impact upon the water quality
    of the stream and its subsequent  output into the Baltimore Harbor.  Spe-
    cific attention will be focused upon the development of an urban nonpoint
    source data base suitable for use as a planning and management tool in the
    evaluation  of local, regional and national problems and solutions.

    Monitoring  is a  critical facet of. the Project, with requirements defined
    by data needs.   JFURP Monitoring  is summarized in the following components:

    1.   The monitoring  of quantity and quality of the Jones Falls stream
        during  base-flow (dry weather) conditions.

    2.   The monitoring  of quantity and quality of the Jones Falls during
        high flow (storm events).

    3.   The monitoring  of quantity and quality of rainfall and runoff during
        storm events at five selected small homogeneous catchments of pro-"
        dominant  land covers in the watershed.

    4.   Atmospheric  deposition quantity and quality monitoring:   dryfall and
        precipitation.

    5.   The quantity and quality monitoring of sanitary sewer overflows and
        direct  sewer discharges during base-flow and storm conditions.

    6.   Industrial/conmercial NPDES discharge monitoring for load assessment.

    7.   Collection of stream bottom sediment  samples throughout  the year to
        define  seasonal conditions.

    8.   The collection and analysis of street dust  and  dirt to assist  in the
        evaluation of pollutant  source accumulation and  non-structural  house-
        keeping management practices.

    9.  Supplemental rainfall  monitoring throughout the  watershed.

  1O.  A range of miscellaneous activities designed to  support  the primary
       components.

    There are varying degrees  of dependence between these  facets of moni-
    toring:   the ultimate  goal  is, of  course,  to complement  the  knowledge
    gained with a perspective  which recognizes the  effects of  one  element
    upon another.  This approach is calculated to provide  the  input necessary
    for  tne definition and implementation of  a practicable  water quality
    management strategy.
                                      G8-16
     The monitoring of base-flow and storm conditions  in  the  Jones Falls and of
     urban  runoff at  the five small homogeneous catchments  relies  upon  auto-
     matic  samplers and flowmeters.  Base-flow samples are  collected  biweekly.
     Storm  sampling depends upon the activation of  the automated sampling
     equipment by an  associated pressure transducer type  recording flowmeter to
     permit the collection of discrete samples at a number  of points  along  the
     runoff hydrograph.  The flownieter places an event mark on  its strip chart
     in order to record the time at which each sample  is  taken.

     Flow rates for each monitoring station are derived from the stage measure-
     ments  recorded by the flowmeters.  Natural controls  were used to develop
     stage-discharge  relationships wherever possible;  artificial controls were
     installed at other locations.  In addition, chemical gaging techniques are
     being used to verify rating curves in storm events.

     The collection of dryfall and wetfall samples is  also  being performed  with
     automatic equipment.  In addition, a continuous recording, tipping-bucket
     raingage with a  sensitivity of O.01 in. was installed  near or within each
     study area to provide the required rainfall information.  Supplemental
    •rainfall data are being supplied by the National  Weather Service long-term
     gages and eight  supplemental gages maintained by  LEGS; these  are being used
     to enhance the data base as well as to check data collected by JFURP equipment.

     A combination of automated and manual techniques  is  being used for other
     monitoring elements associated with discharges to the  Jones Falls.   These
    methods have been outlined by several publications,  including the  NPDES
    Compliance Sampling Inspection Manual.

    Street dust and dirt samples arc collected during daylight hours by a
     field crew using an industrial wet/dry vacuum cleaner.   Subsamples are
     collected within the small homogeneous catchments by running  the vacuum
     cleaner intake along the street surface from curb-to-curb.

     The collection, handling,  preservation and analysis  of all samples re-
     sulting from JFURP activities follow procedures which  have been  outlined
     by the II. S. EPA and supplemented by project-developed methodologies.

C.  Controls

    An important facet of JFURP is the evaluation of certain pollutant  control
    or management  practices for removal efficiency, cost-effectiveness, and
    feasibility of application.  The following two practices have been  identi-
    fied for evaluation:

    1.  An assessment of the efficacy of a total  watershed "best urban  house-
        keeping practices" strategy and its comparison to existing practices
        employed by Baltimore  City.

    2.  Study the  efficacy of  Lake Roland as a water quality/quantity de-
        tention control  structure.
                                                                                                                                 G8-17

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    The study of urban housekeeping practices (including street, alley, and
    stonndrain cleaning; animal litter control;  and general sanitation) will
    examine the feasibility of applying these methods  in low to high density
    coninercial and residential areas within the  Jones  Falls Watershed.  This
    element of JFURP is significantly affected by a number of items, including
    economic restraints and the existing drive toward  urban revitalization
    within Baltimore City.  Communities within Hie city are, for the most part,
    wu11 -organized and vocal in the protection of local interests.  The socio-
    political aspect of this cannot be neglected:  uniformity of solution may
    not generally apply.  Management strategies  should attempt to satisfy the
    needs of the communities with their multiplicity of competing objectives.

    The study of Lake Roland and its efficacy as a management practice is
    boing performed in the following manner:   the Lake Roland Clean Lake
    Study, supported by the U. S. EPA Section'314 funds, will gather one year
    of base-flow and storm event water quality and quantity data.  In a co-
    operative effort, JFURP and the Clean Lakes  Study  will examine the cur-
    rent condition of Lake Roland and its efficacy as  a management practice.
    JFURP has assumed a secondary posture in  the collection and evaluation of
    information gathered.

D.  Progress to Date

    The progress of tho various aspects of the Project is suninarized below:

    1.  The collection of  base-flow and storm event samples occurs regularly
        at the stream monitoring stations;  activities  were initiated in
        October, 1080.

    2.  The collection of  storm event samples occurs regularly at the five
        small homogeneous  catchments; activities were  initiated in early 1981.

    3.  Flow rating curves for all sites are  being developed.  This task is
        approximately 75%  complete.

    4.  Dryfall and wetfall  samples are collected regularly at JFURP
        atmospheric deposition stations.   This includes the compilation
        of rainfall data as  provided by the continuous recording, tipping-
        bucket raingagcs.

    5.  The monitoring of  sanitary sewer overflows occurs regularly in
        conjunction with stream monitoring events.

    6.  A strategy for  the monitoring of direct  sewer discharges awaits
        field implementation.

    7.  A strategy for  industrial/comnercial  discharge monitoring awaits
        implementation.

   • U.  ins11-earn bottom sediment sampling is  underway.

    9.  A strategy for  the collection and analysis of  street dust and dirt
        samples has been developed and sampling  was initiated in October, 1981.
                                    G8-18
1O.  Field sampling associated with the Lake Roland Clean  Lakes Project
.     has been completed and a draft final report  is hearing completion.
     JFURP has received raw data collected  throughout  the  study:  its
     review is forthcoming.

 As might be expected in any project of this scope, numerous problems
 were encountered during the first months of work.  Base-flow monitoring
 has proceeded smoothly; the sampling of rainfall events,  however,  has
 been less successful.  Automated equipment must be used because of the
 capricious nature of rainfall patterns and limitations in budgeted re-
 sources.  Unfortunately, experience has proven that automatic  equipment
 is capable of mischief.

 The overall project plan of action attempts to correlate  all facets of
 the study in a systematic fashion and, in doing  so, admit for  the  proba-
 bility of mechanical and operator error.  Experience  results in the intro-
 duction of proper control techniques to assure system reliability  and col-
 lection of accurate data through a rigid quality assurance program.  JFURP
 has reached a stage where the most prominent work elements continue in an
 orderly manner toward the achievement of objectives with  high  quality data
 results.  Analysis of project data proceeds toward the achievement of stated
 objectives.
                                                                                                                                       G8-19

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NATIONWIDE URBAN RUNOFF PROGRAM
       WACCAMAW REGIONAL
      PLANNING COMMISSION
        MYRTLE BEACH, SC


         REGION IV, EPA
             G9-1

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                                                                                                                     PHYSICAL DESCRIPTION
                              INTRODUCTION
The 208 Areawida Water Quality Management Plan for Maccamaw Regional Planning
and Development Council (VIRPDC) was based upon a comprehensive inventory,
analysis and quantification of water pollutant sources within the region.
Water quality problems were prioritized and addressed in the 208 plan reports.

One of the .recognized water quality problem areas Involved stormwater from
the City of Myrtle Beach.   Stormwater from Myrtle Beach is discharged direct-
ly onto the beach or into  various swashes which flow across the beach into the
Atlantic Ocean.  There are more than 280 direct pipe discharges onto the
beach within the Myrtle Beach city limits.  While some of the small pipe dis-
charges are from swimming  pool drains and pool filter backwashes, more than
160 are direct stormwater  discharges from streets and property drains.  The
city of Myrtle Beach felt  that these beach discharges adversely affect water
quality, beach erosion and beach appearance.

Preliminary sampling of these beach discharges indicated they had high
bacterial counts.  Based on this sampling, a detailed stormwater runoff study
was proposed that would develop the solutions necessary to correct the exist-
ing water quality problems which resulted from the urban stormwater runoff.
This runoff study was accepted by EPA Headquarters as part of the Nationwide
Urban Runoff Program.
A.   Area

The area being studied includes the commercial strip and bathing
beaches along the "Grand Strand" area of Myrtle Beach.

B.   Population

Myrtle Beach and the Grand Strand area entertain over 6,000,000
visitors per year.   Myrtle Beach alone hosts up to 250,000 visitors
on major holiday weekends.   The area's largest industry of course
Is tourism.

C.   Drainage

The drainage consists of pipe systems draining directly to the
beach area.

0.   Sewerage System

The Myrtle Beach area is served entirely by separate sewer systems.
                                  G9-2
                                                                                                                          09- 3

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           1 « « «. § a « a  /
            V       /
             •>-,     /
              i    /
              \   /
                                              NORTH     CAROLINA
        O
  >  SOUTH    c A  R Q'L I N
'i                   >>       V
                                           LOCATION
                                                            LOW r. ON
                           G9-4
                                                                                                                     PROBLEM
A.   Local Definition (Government)

The Waccamaw Regional Planning and  Development Council  received a grant from
the USEPA in June 1975 to prepare an areawide water quality management plan
for the H ace am aw region.   The Uaccanaw Regional 20U Areawitie Water Quality
Management Plan, completed in 1978, contained strategies for local water
quality Improvement through integration of various federal pollution abate-
ment requirements-municipal,  industrial, residual wastes, stocmwater runoff,
groundvtater pollution abatement-and placed the responsibility for planning
and implementing these requirements with regional and local agencies.

The 208 Areawide Mater Quality Management Plan was based upon a comprehensive
inventory, analysis and quantification of water pollutant sources within the
region.  Water quality problems were prioritized.

One of the recognized'water quality problem areas involved stormwater from
the city of Myrtle Beach.  Stormwater from Myrtle Beach is discharged directly
onto the beach or into various swashes which flow across the beach into the
Atlantic Ocean.  There are more than 280 direct pipe discharges onto the
beach within the Myrtle Beach city  limits.  While some of the small pipe dis-
charges are from swimming pool drains and pool filter backwashes, more than
160 are direct stormwater discharges from street and property drains.  The
local government feels that stormwater runoff adversely affects water quality,
beach erosion and beach appearance.

A 1972 study by EPA Indicated that  many of the Myrtle Beach stormwater discharges
had high bacterial counts.  The discharges were cited by the study as posing
a potential health hazard along the extensively developed and utilized beach.

Two stormwater pipes discharging onto the beach were also monitored, sampled
and analyzed during the 208 study.   The sampling occurred in October 1976.
The bacteriological results of the  sampling confirmed the initial EPA findings
as to the seriousness of bacterial  concentrations in the stormwater being
discharged onto the beach.

Based on this work, Waccamaw RPOC and South Carolina Department of Health and
Environment Control concurred that  the Myrtle Beach stormwater runoff was a
high priority state problem.

The two levels of government felt that Myrtle 3each's stormwater problem
required attention because large quantities of materials contained in the
urban runoff enter Withers Swash or flow directly onto the beach and into
the ocean waters.  They felt that the seriously degraded water quality in the
surf has the potential for containing disease causing bacteria that could
affect anyone swimming in, using, or eating food obtained from those waters.

The Myrtle Beach area provides the  attraction for very extensive tourist
tride, which is the prime revenue producing "industry"  of the Grind Strand.
The local decision makers felt that the water quality problens that they
felt existed potentially threatened the source of tourist expenditures in
South Carolina.

                               G9-5

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In addition to the water quality problem,  another major area of concern to
the local government was the beach  erosion.   Stormwater runoff from the city
of Myrtle Beach causes extensive beach  erosion after every significant rain-
fall.  Runoff is collected in the Stormwater  system and transported to the
over 160 pipes discharging directly onto  the  beach.  As the runoff flows
from the discharge pipes,  it erodes the beach sand and creates pools and
gullies across the beach.

These pools and gullies are usually smoothed  out to the high tide line by the
erosion and deposition action of the  tidal cycles.  The gullies enable the
tides to reach further up the beach to  the pipe discharge points.  As the
sand bank around the discharge pipe dries out after rain storms, the tidal
action in the gullies creates further collapse and erosion of the drain line.
This erosive action continues as long as  Stormwater flows across the beach
or until the tides have filled In the gullies.

Runoff front the numerous paved parking  and terrace areas between the beach
and Ocean Boulevard often Is not collected by the Stormwater system.  It
flows as sheet runoff across the paved  areas  and falls directly onto the
beach.  This sheet runoff  contributes to  erosion along the remnant of the
dune line that still exists so that structural retaining walls are necessary
to prevent further loss of soil  and property.

The appearance of the beach is also something the local government Is
concerned about.  Over 280 pipes, many  corroded, chipped, and supported on
make shift wooden braces that extend  further  across the beach each year as
beach erosion continues, are a current  feature of Myrtle Beach's prime
tourist attraction.  Unsightly,  stagnant  runoff pools on the beach also
detract from its appearance.

The local officials are interested  in correcting both the storrawater quantity
and quality problem that exists in  Myrtle  Beach.

8.   Local Perception

The local population Is of course concerned about the Stormwater problem If
It means losing some of the tourist industry.  The local resident population
however, is very small compared to  the  number of tourists that visit the
area.  The tax base generated by local  taxes  Is nowhere near that needed to
finance any cleanup of the problem, if  in  fact it is determined that one Is
needed.
                                G9-6
                          PROJECT DESCRIPTION
A.   Major Objective

The Myrtle Beach Stormwater study was designed  to  provide  Myrtle  Beach,
Kaccamaw RPOC, EPA and South Carolina OHEC with specific  information that
will enable decisions to be made regarding Stormwater  runoff  related water
quality problems.  First, the seriousness of water  quality problems  was  to
be determined through a sampling progran.  The  second  objective of  the study
was to Identify, screen and recommend solutions that would reduce the amount
of pollutants entering the surf from Stormwater runoff.  Preliminary engi-
neering design and cost estimates for the best  runoff  control  alternatives
were to be developed and presented.  A third objective was to  identify,
examine the applicability of, and recommend non-structural runoff control
measures for  implementation by Myrtle Beach and Horry  County.

To provide a gauge against which to compare the costs  of runoff controls, the
study had a fourth element which involved examination  of the  economic costs
to the city and region of taking no action to control  runoff.  This  "no  action"
alternative projects the impacts to the  local economy  of a decline  in tourist
numbers if continued water quality degradation  reaches a magnitude  where
closing the beach after storms might be  necessary.

B.   Methodologies

Extensive bacterial sampling was performed to gather  information  on  the  quality
of recreational and other waters within  the commercial section of town during
dry and wet conditions.

In the beginning of the project all existing direct discharges to the beach
were inventoried in an attempt to select primary and secondary sampling  sites.
It was decided upon that 120 of 160 discharges  to  the  beaches  and swashes
were to be selected for initial sampling.

The spurces of the conforms were to also be defined.  The ratios of fecal
coltfbrm to fecal strep were used to determine  if  the  sources  were  primarily of
human or animal origin.

In order to evaluate the water quality of direct beach discharges,  pipe
streams flowing across the beach, and natural beach pools, established
South Carolina water classification standards were used  for comparison.
However, there are no South Carolina water classifications standards which
are applicable to direct beach discharges, pipe streams, or natural  beach
poo Is.

C.   Monitoring

A total of 289 separate and distinct Stormwater pipes  discharging directly to
the beach  inside the Myrtle Beach City  limits were identified, located,  and
inventoried.  Based on the  inventory,  120 pipes were  selected  for more in-
tensive sampling.  The location of  these selected  pipes  ind random  sampling
stations ara  shown  in the following maps.
                                                                                                                       GO-7

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The City of Myrtle Beach was divided into six contiguous  sections  according
to predominant land use.  A brief description of  each  section  is  shown  in  the
following table:
               Location

               North Myrtle
               Beach City
               Limits to
               69th Ave.
               North

               69th Ave. North
               To Sunset Trail

               Sunset Trail to
               Hampton Circle

               Hampton Circle to
               39th Ave. North

               29th Ave. North to
               20th Ave. South

               20th Ave. South to
               South Myrtle Beach
               City Limits
Predominate Land Use

     Open Space
     Mixed Residential
     and Commercial

     Residential
     Mixed Residential
     and Commercial

     Commercial
     Mixture of Commercial,
     Residential,  and Open
     Space
Direct Beach Discharge No.

        1-12
        13-15


        16-20


        21-33


        34-111


        112-120
After initial sampling, it was decided that  Section  5 would be  intensively
sampled since this section contained  the majority  of the commercial  section
of the city and this was where the tourist population was centered.

Samples were collected from 4 places  during  wet  and  dry periods: direct beach
discharges, swashes, surf, natural pools.  Samples were collected during the
storm, 4 hours after a rainfall event and 24 hours after 4 rainfall  event.
Samples were also collected during dry weather as  a  means of comparison.  The
samples were analyzed for fecal coliforra and a selected group of metals.

0.   Controls

Alternative control  methods, structural and  nonstructural, were identified and
screened in an effort to select three to five alternatives having cost-
affective potential.

The structural and nonstructural  control alternatives considered included
ocean outfalls, disinfection, collection, transport, and release at  selected
locations, collection and discharge to the Intracoastal Water Way, use of
porous paving and any combination of  these measures.

The four basic structural alternatives considered  for controlling Myrtla
Beach's runoff were: ocean discharges, collection  and diversion, disinfection
and infiltration.
The evaluation procedures for the alternatives considered hydrology,  storm
frequency, and engineering economics.  A detailed analysis was performed  to
establish the hydrologic characteristics of each of 25 areas or  subbasins
that contribute storm runoff to the section 5 portion of Myrtle  Beach.  This
analysis established a methodology for determining peak and  total  storm flows
for rainfall frequencies that would recur on an average of 3 month, 6 months,
and 1, 5, 10, and 25 years.

The frequency of the storms was considered.  The cost evaluation prepared
show that the rankings of alternatives for controlling both  the  one-year
and the 25 year storms are identical.

Cost evaluations of alternatives were made using a discount  rate of 6 7/82,
an evaluation period of 20 years, service life of the punping facilities  of
30 years, and service life of structures and piping of SO years.

The alternatives were evaluated in terms of initial costs, capital  and O&M
costs.

Several reports were submitted by Waccamaw RPOC which included evaluations
of the selected alternatives.  The final list with costs was the following:
Alternative

Ocean Discharge from
one outfall pipe with
disinfection

Ocean discharge from
four outfall pipes with
disinfection

Ocean discharge from
four diffusers

Intracoastal Waterway
discharge

Ocean discharge from
one diffuser
Construction Cost with  Interception  Sewer  in  Beach

                    32,800,000



                    37.700,000



                    40,000,000


                    41.300,000


                    44,500,000
                                                                                                                            G9-9

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I   _. JJggpg*gfSs£
                        69-10

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R./MMOOIW  SAMPLlNO
             G9-12
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                                                                                          RANOCM
                                                                                                              STATCNS
                                                                                                                              vtYRTLi   5EACH  i

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RANDOM SAMPLING STATIONS
         G9-14
                                    MYRTL£   =£A



                                  j  STCPM jr*e.i ">

                                                                                                         G9-15

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G9-16
                                                                                                  G9-17

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ST~EHT i/IO SOJflCS
             G9-18

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NATIONWIDE URBAN RUNOFF PROGRAM

 NORTH CAROLINA DEPARTMENT OF
      NATURAL RESOURCES

      WINSTON-SALEM, NC

       REGION IV, EPA
          630-1

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                              INTOHHICI ION
In Hnrlh Carolina, t.he industries and overall  population are  relatively dispersed.
Consequently, water (wllution effects characteristic of large urban cities  in
other parts of the nation are not pronounced.   Only 3/.3 percent of North Carolina s
1970 population of 5,082,059 lived in standard metropolitan statistical areas (SMSA's).
Nationally, 68.5 percent of the population is  centered  in  SHSA  populations.

Seven SMSA's are designated in North Carolina:  Asheville, Burlington,
Charlotte-Gastnnia, Fayetteville, Greenshoro-Uinston-Salem-lligh Point, Raleigh-Durham,
and Wilmington.

The Piedmont, where 54.1 percent of the population Is  in urban  areas,  is  the most
urbanized region  in the State.

A large (Kjrtion of the state's urban population is located in a string of cities
from Gastonia and Charlotte, through Greensboro to Raleigh.   Similarly, a  large
portion of the manufacturing industry is concentrated  in this area  tended  the
"Piedmont. Crescent."  The Cresent is a dispersed urban  region;  no  single  city
dominates.   The development of this clustered  cresent was  originally  influenced
by a railroad line and has since been reinforced by the construction  of  Interstate 85.
Three district clusters make up the Crescent:   the Hetrolina  area  (centered in
Charlotte),  the Triad (Greensboro-Winston-Salem-lligh  Point),  and the  Research
Triangle (Raleigh-Uurham-Chapel Mill).

In North Carolina, several studies have been carried  out to determine the magnitude
of water quality  problems associated with urban runoff.  Many of these  studies were
conducted in the  urbanized Piedmont Crescent.   The results of the  studies  showed
that the Central Business District and other commercial  land  use areas were found
to generate  the highest pollutant loadings for most of  the pollutant  parameters
monitored.  Additionally, work conducted by the Division of Environmental Management
found urban  streams In Asheville to be severely biologically  degraded.

The Winston-Salem area was designated by OEM as a priority area in  the  first  phase of
statewide 208 planning process, due to the concentration of urban  and industrial
activities.  Additional significance in choosing Uinston-Salem  as  a study area lies
in the fact  that  the city  is the first major urban center  (fourth  largest  city in NC)
below the headwaters of the Yadkin River.  Runoff from  from almost  all of this urban
area is received  ultimately by the Yadkin River, the  major potable  surface  water
supply for many communities downstream.

In conjunction with the Forsyth County Environmental  Affairs  Department,  sampling
in Winston-Salem was  Initiated in January, 1978, to examine the water quality
impacts of both Central Business District (CBO) and residential land  uses.   Each
stream station was sampled during low flow and several  during stormflow conditions
for nutrients, heavy metals, dissolved oxygen, BOD, and fecal coliforms.  Biological
sampling was also conducted on a (|iiarterly basis in Tar Branch, the stream  the Central
Business District discharges  into.
The results of this study were consistent with earlier  studies.   That  is,  concen-
trations of most pollutants were higher  in  the Central  Business  District diiriiH)
the period sampled.

In addition to monitoring for physical/chemical  parameters,  biological  sampling
was conducted which showed the urban  streams  to  have  "poor water quality conditions.

The urban stonnwater section of the North Carolina  Water Quality Management Plan
identified various techniques that could be used to reduce urban runoff pollution.
The purpose of the Uinslon-Salem urban runoff project was to evaluate  some of the
techniques mentioned in this plan under  a variety of  real world  conditions.
                                      GlO-2
                                                                                                                                        filO-3

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                          PHYSICAL lit SCRIPT ION
A.   Area
li.
.C.
     The II ins tun- Sal em NIJKP project encompasses several jurisdictions including
     Forsyth County and I he city of Uinston- Salem.

     I uc j I. c-d in north central  North Carolina in the middle Piedmont Plateau,
     Forsyth County is characterised by a foothill  terrain.  Elevations range
     trum a low of about 700 feet along the Yadkin River to points of about
     111)0 feet along the divide between the Dan-Roanoke Basin and the Yadkin
     River Basin, with an average elevation of about 870 feet.

     I lie soils of the county are extremely varied and highly intermingled.   The
     soils present a wide range of percolation characteristics,  depth to water
     table, depth to bedrock,  erodabilHy, and other factors.

     (hi: quality of the gronndwater for Forsyth County is good and the mineral
     content is low.  The dissolved solids content ranges from about 30 to  160
     my/1 , but is generally between 50 and 100 my/ 1.

     Winston- Salem is the major urban area in Forsyth County and is located in
     the central  part of the county.  The city has a total land area of 61.6
     square mi les.

     Approximately t!l% of the laud area in Winston-Salein is in residential  and
     related uses.  Industry accounts for about 7% of the area.   Commercial use
     accounts for another 7%,  and the remaining SI is in vacant  lots.

     Thu average annual temperature is 50.5°F, with an average monthly temperature
     of 1l°F in Oecember to 78°F in July.  Precipitation averages about 44.2 inches
     per ye 6 1'.

     Summer rainfall is characterized l>y thunderstorms with occasional hail.
     Iliriler rainfall results mainly from low-pressure storms arid is less variable
     than summer rainfall.  Ihe total snowfall in Fursyth County every v/inter
     ranges from one inch to two feet with an average total amount of nine  inches.
      Ihe Hj/a population estimate for I orsyth County is 233,600.  Future projections
     done in 1976 were 238,200 by 1980 and 260,900 by 1990.

     Drainage

     Urainuge patterns in Forsyth County follow three main directions.   A very
     small fraction flows eastward and is received by the Cape Fear River.
     Approximately 'i'ti of the county's drainage flows north and is contained
     within tht Uan-Koanuke River basin.  Southwestward flow into the Yadkin
     River accounts for approximately 78l of the drainage.

                                         Glu-4
                                                                                                 The Yadkin River is located on the western boundary of the county.   The
                                                                                                 two major tributaries flowing into the Yadkin River from Forsyth County
                                                                                                 are Abbott's Creek (drainage 25.3 square ariles in forsytis County), as;d
                                                                                                 Muddy Creek (drainage 159.2 square miles in Forsylh County).  The Muddy
                                                                                                 Creek basin drains a major portion of urban Forsyth County, including
                                                                                                 all of Winston-Salem, portions of the municipalities of Kernersville
                                                                                                 and Rural Hall, and portions of the unincorporated communities of Malkertown
                                                                                                 and Clemmons.  Muddy Creek tributaries and their drainage areas from
                                                                                                 north to south include Mill Creek (32.2 square miles). Silas Creek and
                                                                                                 Little Creek (18.9 square miles,) Salem Lake and Salem Creek (69.6 square
                                                                                                 miles), and the Forsyth County portion of South Fork Creek (36.8 square
                                                                                                 miles).  The Abbott's Creek watershed drains southward into High Rock
                                                                                                 Lake.  The remaining of the county is westard directly into the Yadkin
                                                                                                 River, eastward into the Maw and Deep Rivers, and northeastward into
                                                                                                 the Dan-Roanoke River Basin.  These drainage areas are shown in Figure 111.A.'

                                                                                            D.    Sewerage System

                                                                                                 The entire area of Winston-Sal em is served by separate storm sewers.
                                                                                                                                    G10-5

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                                          NORN CAROM
                                           RIVER BASINS
                              IO&H/-N;
                              ,WINSTON-    x  .
                                 _0 SALEMQ  1  O
01
02
03
04
05
06
07
Broad
Cape Fiar
CaUwbJ
Chowan
French  Broad
Hiwasset
Little  Tenn.
Saunnab
                UC
 08    Umber
 09    Neust
10114  Kew-Watauga
 11    Pasquotank
 12    Roanoke
 13    Tar-Panlico
 15    White Oak
 IB    ladkin-Pee  Dei
WILMINGTON
                                             THE STATE OF NORTH CAROLINA

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                              PKG.IECI AKEA
1.    Cattluuent Name - NC IU23 Ardiiiore

     A.    Area - 324 acrts.

     B.    Copulation - )U4b persons.

     C.    Drainage - Burke Brancli is a tributary draining the Ariliuore
          residential district.

     I).    Sewerage - Drainage area of calcluuent is 97.7* separate storm
          sewers.   2.3% is served by on-site systems.  All of the separate
          storm sewered aroa has curbs and gutters.  Streets consist of
          26 miles of asphalt.

     t.    Land Use

          3u.y acres (122) Urban Parkland.

          5.73 acres (2*)  is Liyht Industrial.

          b.M dcres (2i)  is Linear Strip Development.

          . y!) acres (< 1%) is 78 dwelliiuj units per acre residential.

          2b'J.36 (83%) is  2.5 to U dnulliny units per acre.

II.   Calcluuenl Name - NC 1013 Central business District

     A.    Area - 22.7 acres.

     b.    Copulation - U persons.

     C.    Liramaye - Site  is a stonu sower draining into Tar Branch Tributary
          to Muddy Creek.

     U.    Seweraye - Drainage area of catclunent is 100% separate stonu sewers.
          All of the separate stonu sewered area has curbs and gutters.  Streets
          consist  of 3.68  miles of asphalt.

     E.    land Use

          22.7 jcres (10U£) is Central business District
LOCATION  OF WATERSHEDS TO'St MONITORED
                                    G1U-B
                                                                                                                                     G10-9
                                                                                                                                     .•, i-'

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^^m^m^fff^^^y\ vx~fr^i>
S& \: ftllSw M, fg^r m^
       Minstnii-Saleni, N.C.

        Central Business District Site


          G10-10

                                                                       &\%i( •\M\t@M
                                       ' •vUVr^-'.'Jnv.Jl'
                                       -.  :.vV^_,  AV.-.\I/
                    /  I  '^^,
       , N.C.

Ardiiiore Rosidcntiiil Site
                                                            Gin-11

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                          PKOJtCI  UtSCKIHTlOM
A.   Major Objective

     The primary ubjective of the Uinston-Salem  HIIRP project  is to evaluate street-
     related, non-structural  practices  for  relative pollutant  removal cost and
     effectiveness potentials under a variety  of real world conditions.   Street
     cleaning and catch-basin cleaning  activities in already developed urban
     areas were evaluated.  Tyraco Regenerative Air Sweepers and various cleaning
     frequencies were investigated in small-scale field  tests  and larye-scale
     program tests in selected watershed.   Small-scale tests  included determination
     or accumulation rates of street surface solids by weight  and particle sue
     distributions and associated, attached contaminants.

     Larger scale proyraiiauatic tests included  cost determinations, as well as
     benefits to water quality, leading to  the development of  an optimal  cost-
     effective program.

     Determination of the seasonal atmospheric fallout contribution which can
     accumulate on streets and other impervious  surfaces and  subsequently be
     washed off and a determination ol  the  pollutant contributions washed out
     of Ihu atmosphere by precipitation were made.

     The watersheds monitored are representative of about 8UJ of the land area
     of Winstoii-Saleiii, and a  lanje percentage  of most urban areas in North
     Carolina.  The CBU watershed was studied  because of the  associated high
     concentration of pollutants and potential efficiency of management for
     this type of land use.  The residential area, although having relatively
     lower pollutant concentration in runoff accounts for a large majority
     of tin- city area and thus a larye  overall pollution potential.

B.   Hotho>1ulO'jies

     Hie full scale tests of  Best Management Practices was divided into four
     subiasfcs. These four subtasks included  1)  accumulation  rate determinations
     2) pollutant/particle size determinations,  3) street cleaning equipment
     performance determinations, and 4) catch  basin cleaning  performance
     determinations.  Each of these tasks were necessary to accomplish the main'
     objective of the study.

     1.   Accumulation Kate lletenninations

     A knowledge of the accumulation rales  of  solids on  street surfaces and
     surrounding impervious surfaces is important in determining the amounts
     of associated pollutants that accumulate  on these surfaces.  Past studies
     had shown that accumulation rates  vary widely between areas due to street
     surface characteristics, land use  patterns, traffic conditions and other
     local factors.
                                          tilO-12
Solids accumulations within eacli watershed were studied by collecting
representative samples from the streets and sidewalks.  An experimental
design was carried out In each watershed to determine the number of  subsampies
needed to statistically represent the variation found in the watershed.   Due
to cost constraints however, only 50 strips were chosen randomly throughout
the watershed.  This number is less than the number needed to adequately
represent the variation.

The experimental  design study was carried out in each season, in both  watersheds,
to determine the required number of subsampies for a representative  watershed
sample.

Accumulated solids on strips of street were then collected with a  small-scale,
hand-held, vacuum cleaner capable of removing and retaining particles  as  small
as five microns.

Watershed accumulation studies were carried out in essentially the same manner
as the experimental design studies.  The exception was that larger capacity vacuum
cleaners were used in the full scale tests to accomodate the collection and
retention of the larger watershed representative "sample".  Solids  accumulation
within each watershed was determined by taking weekly samples within each watershed
for a period of 12 months.

Collected solids  in each sample were analyzed for wet and dry weight,  particle
size distribution and median paticle size class based on the weight  fractions
of size classes.   All particle size fractions were retained for each watershed.
Size fractions from each weekly sample were composited on a monthly  basis by
watershed and analyzed for several pollutants.

Because of the possibility of across the street variation in solids  loading on
streets and sidewalks, seasonal studies were carried out to evaluate this possiblity.
Street lengths of 10 feet considered to be representative of the test  areas were
chosen.  A number of pavement strips of afferent width were vacuumed,  solids
collected, removed, and retained for particle sizing and pollutant analysis.

2.   Pollutant/Particle Size Determinations

Many of the accumulation rate determination studies have associated  particle sizing
of solids collected, and pollutant analyses for each separated particle size
class.  These pollutant analyses are important in determining the  relationship
between particle  size and associated pollutants and in drawing conclusions from
these analyses.

The weekly samples collected in the watershed accumulation studies were separated
into particle size fractions which were weighed and retained.  These size fractions
from weekly samples were composited by size class on a monthly basis.  The
composited, monthly size fractions were analyzed for eight pollutants  of  interest.
                                                                                                                                         GIG-13

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                                                                                                                              PROBLEM
     •*•   jiLLi?.'J-LlSffiLlU-El".ipment performance  Determinations

     Vacutun cleaners were investigated under a variety of  real-world operating conditions
     to determine the pounds  of solids removed per curb-mile and the particle size
     distributions in samples taken from  street  surface tests strips before and after
     cleaning operations.

     Particle size determinations provided  for estimates of associated pollutants
     removed based on information determined in  the pollutant/particle size association
     studies.  Calculations were also  made  to determine the median particle size in
     each of the samples to allow for  determinations of equipment performances to
     be made as a function of particle size.

     4.   QUch-BasIn Cleaning Performance

     The purpose of this subtask was to determine the accumulation rates of solids
     in test catch basin structures.   Three test structures were chosen to represent
     different siting positions.  The  pollution  abatement  potential of cleaning these
     structures at various intervals was  investigated.  Accumulation periods of two
     weeks, one month, and two months  were  studied.

     Practice effectiveness was evaluated for different accumulation periods by
     determining dry weight amounts (pounds) of  solids removed per structure
     cleaned.  Representative solid samples were removed from the catch/basins
     being studied after cleaning.

     Precipitation events and other activities influencing accumulation were closely
     documented.

     Water quality samples were taken  at  the two selected watersheds before and after
     implementation of the RMP's.  Total  loads washed off  and concentrations were
     compared l:o before and after BMP  implementation as well as to water quality
     standards promulgated by the state of  North Carolina.

     Two sites were also constructed in the Central Business District to supply
     source input for background deposition, and street and curb deposition
     from atmospheric sources.

C.   Monitoring

     Automatic samples were taken at both monitoring locations.  ISCO model 1870
     flow meters and ISCO model 1680 high speed  sequential samplers were used.
     Discrete samples were taken at both  sites.

     Acrochemetrics Model 301 wetfall/dryfalI samplers were used to collect the
     atmospheric deposition samples.   Hut fall samples were collected on an event
     basis.  Dryfall  samplers were  collected on  a monthly basis.

I).   Controls

     As described in the Methodologies section,  both street sweeping practices
     and catch-basin cleaning practices wore evaluated.  The methods used for
     those evaluations are described In Section  B.
A.   local Definition

     Several studies have been conducted  in North Carolina to detenu!ne  the  extent
     of degradation of urban streams,  lliese studies  in Durham, Uoleigh,  Asheville.
     and Winston-Salem have shown that, under present conditions, almost  all  urban
     streams will he unable to meet the 1083 water quality go.ils.

     Many of these studies were conducted  in the urbanized Piedmont Crescent.   Iho
     results of the studies showed that the Central Business District  and other
     commercial land use areas were Inund  to getierate the highest pollutant  load-
     ings for most of the pollutant parameters monitored.  Sitjnif icantly  high
     concentrations of nutrients and heavy metals, notably phosphorus  and load,
     respectively were observed.  Additionally, v/ork conducted hy the  North  Carolina
     Division of Environmental Management  (DEM) in conjunction with the  Land of
     Sky Regional Council of Governments  found urban  streams  in Asheville to he
     severely biologically degraded.

     The Winston-Salem area was designated hy DEM as  a priority area  in  the  first
     phase of the statewide 208 planning  process, due to the concentration of urban
     and  industrial activities.  Additional significance in choosing Winston-Salcm
     as a study area lies in the fact that the city  is the first major urban center
     below the headwaters of the Yadkin P.iver.  Runoff from almost all of this urban
     area is received ultimately by the Yadkin River, Hie major potable  surface water
     supply for many communities downstream.

     In conjunction with the Forsyth County Environmental Affairs Department, samp I Ing
     was  initiated in January 1978 to examine the water quality  impacts  of both
     Central Business District (CBD) and  residential  land uses.   Each  stream station
     was  sampled during  low flow and several during  stoniiflow conditions for
     nutrients, heavy metals, dissolved oxygen, BOD  and fecal colifoniis.   Biological
     sampling was also conducted on a quarterly basis in Tar Branch,  the stream the
     Central Business District discharges into.  The  data  from  these  studies showed
     distinct differences in iwllutant concentrations from the  residential areas and
     the CBD for several parameters.  Concentrations  of most pollutants  were higher
     in the CBD during the period sampled.

     The monitoring also showed that some water quality problems  also  oxist  durint)
     dry weather (low flow) conditions.   During high  flow conditions,  concentrations
     exceeding proposed  North Carolina standards were deinrmstrdtiul for load, mercury,
     iron, and fecal colifonn bacteria.   Elevated  levels associated with high flows,
     hut  not exceeding proposed standards were shown  for zinc,  several nutrient para-
     meters, BOD, and COD.  However, high concentrations of several of the heavy metals.
     particularly mercury, were found during low flow conditions.  High  fecal r.olifotm
     concentrations were also found during low flow conditions.

     In addition to the monitoring for physical/chemical parameters,  biological
     sampling vias conducted which showed  the urban  streams to have "poor water quality
     conditions".
                                                                                                                                      G10-I5
                                         GIO-14

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     Hie urban stonm/ater section of tlie florlh Carolina Water Quality Management
     Plan Identified various techniques that possibly could be used to reduce
     urbdii runoff pollution.  These techniques include both structural and
     MOPI-structural practices.  The objective of the Winslon-Salein study  is
     tu evaluate some of the uon-striictrual techniques for relative pollutant
     removal effectiveness potentials under a variety of real world conditions.

B.   Local t*t!i-ceptign

     The "North Carolina Stonnwater Manager" is a publication put out bi-nionthly
     by the Mater Resources Research Inlstitute at North Carolina State University.
     Thi: purpose of the newsletter is to help consultants, city engineers and public
     works directors in North Carolina who are concerned with stonnwater management
     communicate with each other.  Ihe state has always been a leader in  the field
     of stormwaler management.

     Because of the local interest in environmental problems. Forsyth County formed
     an Environmental Affairs Board in 1976.  The purpose of the board is to encourage
     the wise and beneficial use of the natural environment and minimize the adverse
     effects of environmental contaminants on human health.  The Forsyth County
     Environmental  Affairs Board has played a very active part in the Winston-Sal em
     IIURP project.
                                       GlO-16

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 NATIONWIDE URBAN RUNOFF PROGRAM



TAMPA DEPARTMENT OF PUBLIC WORKS



         TAMPA, FLORIDA



         REGION IV, EPA
              Gll-1

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                              INTRODUCTION
The City of Tampa Department of  Public Works  is charged with solving the, at
limes, conflicting problems  of urban  flood control and runoff generated water
quality deterioration.  Large portions of Tampa have been developed with
little, if any, drainage provisions and the consequent flooding is of primary
concern to the citizens.  At the same time, urban runoff has been identified
as a significant source of pollution  to several important local water bodies
(the Hillsborough River including a reservoir, and portions of Hillsborough
Bay).  The areawide Water Quality Management Plan recently completed by the
Tampa Bay RFC classified all land areas within the City limits as segments
with serious water quality problems.  The Florida Department of Environmental
Regulation (DER) has designated  all stream segments within the Tampa Bay Region
as water quality limited, i.e.,  point source treatment is expected to be In-
sufficient to achieve acceptable water quality and thus nonpoint sources must
be considered a significant  portion of the problem.  The DER also recently
enacted stormwater runoff permitting  rules which call for a reduction of
pollution to comply with water quality standards.

To help find a solution to all of these problems, the Tampa Department of
Public Works is participating in the  Nationwide Urban Runoff Program.  Tampa
OPU hopes to use the data collected in the NURP program and develop a plan
for the management of stormwater runoff in the Tampa area.
                                      Gll-2
                                                                                                                         PHYSICAL DESCRIPTION
                                                                                               A.   Area
The City of Tampa lies at the northeast corner of Tampa Bay wd partially
encompasses the Hillsborough Bay System (Figure 1).   Hi I lsborou<|h Bay covers
approximately sixty-five square miles and surrounded by a large metropolitan
complex which supports extensive industrial activity and serves as a major
shipping port.  The Bay is highly eutrophic, and anoxic conditions have been
reported.  The city of Tampa is bisected by the Hillsborough River.  The Bay
and the River serve as the primary ultimate recipients of stormwater dis-
charge.  The Hillsborough River originates some 55 miles northeast of fampa
in the Green Swamp.

Approximately ten miles from its mouth, the river has been dammed to create
the Hillsborough River reservoir.  The predominantly forested and agricultural
(but increasingly urban) drainage basin above the dam is estimated at 630
square miles.  Below the spillway, approximately sixty square miles of  largely
urban area drain into the river.

The Tampa Bay area is a humid sub-tropical area.  Average annual rainfall  is
48.9 Inches, 60X of which falls between June and September (National Oceanic
and Atmospheric Administration).  The rainfall is associated with seasonal
thunderstorms and frontal activity.

Easterly winds prevail during the summer and northerly winds during the winter.
Mean monthly temperatures range from 16.?"C (61.?°F) in January to 27.8°C
(82*F) in August.

Tampa exhibits flat to gently undulating terrain, typically characteristic
of the Gulf Coastal Lowlands in which it is Included.  Elevations range from
sea level along Hillsborough and Tampa Bay, to 87 feet above mean sea  level
(MSL) in the extrane northeastern parts of the City.  Ihe remnants of three
shorelines and four marine terraces, attributed to the rise and fall of the
sea durfng'the periods of continental glaciation, have been identified.

A close examination of a topographic map of the City reveals that the majority
of the City is less than 25 feet above mean sea level (MSL).  This low coastal
area, which originates at the Bay margin, varies considerably in configuration
and is extranely susceptible to adverse weather conditions, specifically, high
tides and tropical storms.  Historical evidence confirms the assumption that
a significant portion of the City is subject to frequent and recurrent  flooding
due to adverse weather conditions, low and flat topography, and a lack of
drainage facilities.

Flooding is a serious natural hazard that should he avoided.  Because Florida
is prone to periods of drought or long periods of less than average rainfall,
many areas which are subject to flooding appear to be high and dry.  Especially
deceptive to many people is the extent of the floodplain associated witli  tropical
storms.  The  low-lying areas surrounding the Bay are extremely attractive  for
residential neighborhoods, and consequently, are well developed.  Since the  last
major hurricane (1960), extensive development in the coastal floodplain has
occured.  Realistically, the next hurricane can inflict massive and catastrophic
damages  upon  the low-lying areas within the City.
                                                                                                                                     611-3

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         Lower HUlsborough  River
PA3CO COUNTN          	
        HILLSBOROUGrTcOUNTT
                                                           Basin Boundaries
                                                              nHILLSBOHOllGti HIVEH
                                                              OPfllNAOE UrtSiN
                                                           B«>inii Wtmm Cilf Limiif
                                                                     nonCiH H;i:vEn
                                                         [
                                                         1 I   I HILLSDOHOIIl'.d UA»
   Figure 1   Ctcy of Taapa Drainag* Areas

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      ^jw'V-^^ii^iJij:  i!
      •(•I :-.*/:..  :.|  ;:  	...-n,'--;*A.'1
STr^mm  iffWmrT^yTTrn?
Beyond the low-lying areas subject to flooding,  extensive  areas within the City
are representative of karst topography.  Evidenced primarily  in the northern
extent of the City, karst topography is characterized  by springs, disappearing
streams, depressions, water-filled depressions,  subterranean  cavities, and
sinkholes.

Tampa may be considered  as being almost entirely developed, with  lew  large
tracts of open land remaining.  This state of development  is  significant  in that
the development  process  has altered existing vegetation patterns, drainage,
soils and groundwater characteristics.  For example, development  of roads, side-
walks, and roof  tops  increases the amount of water that "rims off" a  site; this
extra runoff, above the  natural rate, necessitates the construction of a  storm
sewer system.  This modification of drainage, from a natural  to an artificial
urban stystem, is essentially complete within the City although construction of
storm sewer systems is not yet complete.

Within the incorporated  city  limits of Tampa, a relatively small  amount of
land remains vacant for  development,   the majority of  vacant  lam! exists  near
MacOill Air Force Base and south of Tampa Airport -- undeveloped  land is  also
available around McKay Bay and on Seddon  Island.

Industrial land uses  in  the City are heavily concentrated in  the  areas around
the port  facilities,  with  the greatest percentage located along  the north side
of Adamo  Drive from the  Palm  River area on the east to 13th Street on the west.
From  this location,  industrial usage extends southward to (looker's Point.
Another  large concentration of  industrial usage which exists  ap-irt  from  the port
facilities is located just north of Busrh Boulevard and east  of  30th  Street.
This  area is the Tampa  Industrial Park which includes the well-known  tourist
attraction,  Busch Gardens.  Smaller concentrations of  industry exist  at  the Port
of Tampa  and west of  Westshore Blvd.  in the vicinity of the Westinghouse  Plant.

Commercial development  in  Tampa has  in many cases developed  in the traditional
strip commercial fashion along  the  length of major traffic arterials.  The pri-
mary  commercial strips  are found  on Hi IIsborough  Avenue, Kennedy Boulevard,
East  Broadway,'Busch  Boulevard, Hale  Habry Highway, Armenia Avenue,  Florida Avenue,
and Nebraska Avenue.

The majority of  land  in  the  City  is  in residential usage, primarily  single
family   with multi-family the second  largest category, but representative of  a
significantly smaller amount  of  acreage.  Mobile  home  parks  are a much smaller
residential  use  in the City.

B.    Population

 The  City of  Tampa is located  in west  central Florida.   The corporate limits
encompass 84.45  square miles (8.12*)  of  Hillsborough  County;  approximately half
of the  total population of Hillsborough County  resides within Tampa.  Gross
 population  density per  square mile is 3,351;  total  population (1978) is  282,741.
 This figure represents  a 4 percent increase since the 1970 Census.   Ihe minor
 population  increase  is  not characteristic of  the Tampa Bay region; compared to
most other  jurisdictions, Tampa's population is increasing at a  very slow rate.
 The level of population concentration generally increases  as one moves from the
 downtown Central Business District (CBD) to the corporate  limits.  As a  result,
 large portions  of the population are located in the North  Tampa  and  Interbay areas.
 Gil-6

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C.   Drainage

I lie Illy of lompa Is divided into three major drainage areas:   the Ilil Isborough
River. Hillsborough bay, and Old Tampa bay.  Old Tampa Bay Is  not addressed at
all in this study,  (see map)

  Mi 1Isborough Kiyer

The Hi)Ishorough River originates approximately 50 miles northeast of the
City of Tampa in the Green Swaiup.  The Green Swamp is a large. Ill-defined,
wetland area situated in Suinter, folk, Pasco. and Lake counties.   The swamp
has been determined to be situated directly over a recharge subsurface aquifer.
The swamp is also the origin of two other major central Florida rivers,  the
Uithlacoochee and Oklawaha.  The watershed for the Ilil Isborough River is
generally considered to be approximately 630 square wiles; however, exact
delineation of the basin's area is difficult due to the lace of readily defined
interfluves in the Green Swamp headwaters.  Under certain high water conditions,
the Hillsborouyh River receives drainage that would normally be considered  as
being part of the Uithlacoochee basin.  Ihe Army Corps of Engineers estimates
that intermittent overflows as high as 35,000 cfs have occurred in the  past
(1934) but that the animal average overflow is about 30 cfs.

Proceeding downstream from the Uithlacoochee "overflow channel",  the river  shows
a relatively steep gradient; however,  the floodplain remains quite expansive,
with widths varying between 2.000 to 6,000 feet.  Fox Branch enters the
Ilillsburaiigh at this point.  Fox Branch extends roughly 8 miles to the  southeast,
to its origin near the settlement of Socrum.  Host of Fox Branch  extends through
unimproved pasture, but some citrus and improved pastures are  apparent.   Flows
range from 0 to 100 cfs.  Downstream,  Crystal Springs discharges  to the
Hillsburough through a half mile run.   Ihe springs flow year-around and  assure
a base flow in the river.  Discharges  vary from 20 to 150 cfs.  Big Ditch is a
3-mile long tributary flowing due west into the river.  The headwaters of Big
Ditch originate in an area of surface  mining and phosphate production.

Uowni-leaiu, ui. unnamed tributary flows  south 5 miles through areas of improved
pasture,  citrus,  and at least 20 confined feeding operations around the  out-
skirts of the City of Zephyrhills.

Blackwater Creek  is the first major tributary to the Hillsborough downstream
from Big  Ditch.   Ihis watershed is characterized by extensive  channelization
that has  been developed to manage improved pasture and citrus  groves within
the watershed.  Furthermore, the headwaters of Blackwater Creek and its  major
tributary, Itchepackesassa Creek,  drain urban and suburban development  in and
around Plant City.  Discharges from Blackwater range from 0 to 5,500 cfs.   As
many as 15 confined feeding operations have been identified within the Blackwater
watershed.

Proceeding downstream, an Intermittent stream known as Two-hole Branch discharges
into the  Hillsborough.  Two-hole Branch drains primarily unimproved pasture.
At this point, the HitIsborongh hiver  is associated with a vast hardwood swamp.
Two tributaries,  the New River and an  unnamed tributary,  also  enter at this point.
Ihe New River drains an extensive arou of improved pastures and rangeland,  and
has been  channelized over much of its  length.  Ihe unnamed tributary to  the west
of Hew River has  similar characteristics.
                                    GH-8
The Hillsborough River, at this point, is ill-defined as  it flows through
the massive hardwood swamp.  This swamp is the location of the  lower
Ilil Isborough River Detention Area, and encompasses approximately 15 square
miles.  The detention area, coupled with the nearly complete Tampa Bypass
Canal, is intended to alleviate downstream flooding along the uranized portions
of the Hillsborough River.

Several other tributaries also drain  into this hardwood swamp,  including
Ho11Oman's Branch, Flint Creek, Cow House Creek, Clay Gully and Trout Creek.
Ho11Oman's Branch is an intermittent  stream that is largely channelized.   It
drains rangeland, improved pasture, and several confined  feeding operations.
Flint Creek originates at Lake Thonotosassa, which in turn is fed by Baker
Creek and Pemberton Creek.  Baker Creek and Pemberton Creek drain areas of
mixed land-uses, including hardwood swamp, improved pasture, rangeland, sub-
urban areas, and a small Industrial area.  Lake Ihonotosassa is the largest
lake  in Hillsborough County at 830 acres.  Its stage is regulated by a weir
at the outfall to Flint Creek.  Varying over a range of 2 feet, maximum lake
depth is 14 feet with the deeper areas being covered with benthic muck, a
result of phytoplankton fallout and organic wastes (citrus pulp) trum
industrial sources tributary to Baker Creek.  Lake Thonotosassa experienced
the largest fish kill in the U.S. in  1969.  Flint Creek discharges into the
Hillsborough via an unchannelized section of hardnood swamp.  Average discharge
is 20 cfs, with a range from 0 to 350 cfs.

Cow House Creek is a natural meandering channel of the Hillsborough and is
undergoing substantial modification due to the construction of  the Tampa
Bypass Canal.  Trout Creek and Clay Gully drain predominately land uses north
of the Hillsborough.  Both creeks drain Into the river through  a series of
swamplands which probably reduces water quality problems.

Cypress Creek is the last major tributary in the rural segment of the
Hillsborough River.   Indeed, several portions of the lower reaches of Cypress
Creek contain suburban residential land-uses, including a small airport and
several minor commercial establishments.   The upper reaches of Cypress Creek
basin lies within a trough (50-70 feet) in the potentiometric surface of the
Floridan Aquifer.  Thus, the potentiometric level results in the discharge
of considerable ground water into Cypress Creek.

The Hillsborough River segment downstream from the tributary Cypress Creek to
its mouth at Hillsborough Bay is highly urbanized.   Houses are  located imme-
diately on the river and in some cases are located in the ten-year flood plain.
Urban stormwater drainage from the cities of Temple Terrace and Tampa is
generally routed directly to the river, with little or no retention or quality
control provided?

Water quality sampling efforts indicate that as the river passes through the
urban areas, the water quality is degraded.    Particularly important to the
City of Tampa is the utilization of the IlilIsborough River as a surface reservoir
of raw water for potable uses.  The Tampa water systaii pumps approximately
65 mgd of water from the reservoir and has a plant capacity of 94 ingd.  The
City of Tampa reservoir is formed by tne City dam,  located approximately at
30th Street.  The reservoir water storage currently covers approximately 950
acres.  The water treatment facility  is located directly upstream from the dam.
                                                                                                                                  Gll-9

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The majority of the annual  low Dow of  the river  is diverted through the
waterworks and consumed by  the residents  of the City.  During the wet season,
some water passes over the  dnm; however,  the reservoir pool Is usually main-
tained at approximately 22  m.s.l.,  resulting in the river segment below the
dam being primarily tidal  in nature.

Ten storm sewers of 60° or  larger drain directly  into the Tampa reservoir;
numerous smaller storm sewers and urban sheet flows also enter the reservoir.
Two industrial sources dicharge Into the  river at  this point; McGraw Edison
and Anhetiser Busch both discharge cooling water.   Several residentia'l areas
directly adjacent to the reservoir  utilize onsite  waste disposal systems (septic
tanks), which in times of high ground water levels, may be discharging Into
the rtver.

The segment of the river below the  dam  exhibits characterises of a tidal
stream, varying in width from about 50  feet near  the dam to approximately
300 feet in downtown Tampa.  Depth  varies from a  few  inches to nineteen
feet.  Urban residential, commercial, and industrial uses border most of
the river along this segment.  The  watershed below the dam consists of
approximately 45 square miles, with urban land uses predominating.  This
river segment has the environmental characteristics of a low salinity estuary.
Two river-miles downstream  from Tampa dam is Sulphur Springs, with an average
annual flow of 31 mgd.  Usually the springs discharge directly into the
river; however-, during periods of low river flow,  up to 20 mgd can be diverted
upstream to the reservoir to be utilized  as a potable supply augmentation.
Several other small springs also discharge into the river in this segment.

This segment is also impacted by urban  storm water runoff.  At least 106
stormwater outfalls (24" and above  the  diameter) discharge into the river,
draining almost one-third of the City.  Because of the age of these systems
and the urban development  intensity,  little or no  structural quality control
measures are incorporated.   Both open ditch and closed systems are utilized.
The river finally empties  into Hillsborough Bay at downtown Tampa; the last
1.5 miles are maintained for commercial navigation.

  Hillsborough Bay

The MilIsborough/McKay Bay  systems  are  part of the larger Tampa Bay system,
a complex series of estuaries on the west central  coast of Florida.  Hillsborough
Bay is a natural arm of Tainpa Bay,  approximately  eight miles long and four
miles wide.  McKay Bay is an extension  of Hillsborough Bay.  Hillsborough Bay
has three major freshwater  tr ibutarles, the Ilillsborough River, the Palm River,
and the Alafia River.  Improved channels  are maintained at 34 foot depths.
The surface area of Ilillshoroiigh Bay, including the harbor area. Port Sutton,
and McKay Bay, is 39.6 square miles and the total  volume is 8.3 x 10  cubic
feet at mean low water.  Shoreline  slopes are gentle except at bulkheads,
with the 6-foot depth contour extending some 400  yards off the western shore
and about 1200 yards off the eastern shore.  Bottom configuration has been
altered markely by channel  dredging and placement  of  spoil.

Tides are of the mixed type, having one strong flood  and ebb per day with
an  intermediate phase which may be  either flood or ebb.  The diurnal tidal
ranges is 2.8 feet and the  mean level is  1.4 feet.
                                    011-10
Several major dredge and fill projects have dramatically  altered  natural
configuration of the MilIsborough/McKay Bay systen.   Davis  Islands,  situated
in northern Hillsborough Bay, were dredged  in  the Florida land  boom  of  the
1920's.  tand use on Davis  Islands  is primarily residential,  with a  small
commercial strip', a general aviation airport,  and Tainpa General Hospital.
Seddon Island, directly east of Davis Islands, is currently undeveloped.
Hooker's Point, a natural perisinsula, has been enlarged by  dredging,  and  is
the site of most of Tampa heavy Industry and port terminals.  Connecting
Hooker Point with the eastern shore, and bisecting McKay  Bay, is  the 22nd
Street Causeway.  Port Sutton, on the eastern  shore of Hillsborough  Bay,  is
the site of several shipping terminals and an  electrical  generating  plant.

McKay Bay, named after former Tampa Mayor D.B. McKay,  is  a  small  shallow bay
located at the northeast corner of Ilillsborough Bay.   Before  extensive  dredging
and filling took place in Hillsborough Bay, there was  no  distinct dividimi
line separating it from the rest of Hillsborough Bay.  However, after the
construction of the 22nd Street Causeway and bridge In 1926-1927  and more
recently the dredging and filling of Hooker Point and  Port  Suttnn, McKay has
became a distinct. Isolated body of water.

The present shoreline is 7.5 miles  long and covers 977.8  acres.   The deepest
natural depth for the bay is only 5 feet.  However, a  number  of old  borrow
areas and the dredging of the Tampa Bypass Canal left  areas as  deep  as  12-15
feet.

Freshwater discharges into  the III I Isborough/McKay Bay  systens originate from
the three rivers, stormwater runoff from urban and rural  sources,  and point
discharges from sewerage treatment plants.  The Hillsborough  River's mean
annual discharge is 397 mgd in a natural state (bear  in mind  the  diversion
to the municipal waterworks).  The maximum recorded natural flows have  been
significantly modified by the construction of  the Tampa Bypass  Canal.  The
canal, designed by the U.S. Army Corps of Engineers,  is being constructed  to
prevent the flooding of the Hillsborough River.  Flood surges can be
diverted from the Ilillsborough River to the bypass through  a  series  of  canals
and control structures.   The canal extends partially  into the Floridan  aquifer,
and acts as a collector for groundwater discharges.   Estimates  vary  as  to  the
amount of groundwater entering the canal, the most recent estimate  is between
15 to 25 mgd.  The figure for groundwater discharges,  added to  the natural
flow of the Palm River,  yields an estimate of  90 mgd mean annual  discharge.

The Alaf la River drains approximately 460 square miles of Ilillsborough  and
Polk Counties.  No significant man-induced changes are present  to modify
natural flows.  The average annual discharge is 264 mgd,  with a maximum of
1,118 mgd and a minimum of  4.3 .

Stormwater runoff enters the Bay through closed urban  systems,  open  iirhan
systems, open rural systems, and natural sheet flow.
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                                 PROBLEM
 A.   Local  Uefinition

 Hie Hi IIsburouyh  Kiver/Hil Isborough  Uay  System  quality has declined  to  the
 extent  that many  of  its  beneficial uses  are  now impossible.   The most recent
 general  water quality index for body contact by the  Hillsborough County Environ-
 mental  Protection Ccianission  rated Uillsborsugh Bay  as undesirable for  any
 form or'  body contact.  A once significant  shellfish  industry  estimated  in
 1969 to  be  valued at  $1.6 million, is now  gone.  Aesthetically, enjoyment of
 the river and bay led to the  development of  desirable residential areas along
 the watei front.   Odor, color,  turbidity, and bacterial contamination have
 reduced  the benefits  of  the Bay.  Sporadic fish kills compound the problem.

 Several  incidents and low water  quality  in general,  have resulted in water
 quality  below minimum state standards.   Point sources, urban  and rural  runoff,
 natural  background, and  the dredge and fill  activities all contribute to the
 problem.

 The City ul  Tampa utilises  the Ilillsborouyh  Kiver as a potable water supply.
 Stale water quality standards are the highest for such potable water bodies.
 Urbanization  has,  however,  extensively impacted  this segment of the Hillsborough
 River.   Two cities, Taiupa and Temple  Terrace route urban stormwater into the
 reservoir segment.  The  City of  Tampa alone  has  eleven outfalls, 24 Inches
 or larger,  discharging into the  Reservoir.   Hater quality problems are  further
 compounded  by upstream rural runoff  from agricultural lands, and large blooms
 of water hyacinths in  the reservoir.   Runoff adds nutrients, suspended solids,
 and coliform  bacteria  to  the water supply; water hyacinths add to the nutrient
 problem, and  upon  their death, contribute  to a  low dissolved oxygen problem.
 Runoff from a  large development  bordering on the Hillsborough River north of
 Temple lerrace will probably have to be treated  to at least maintain  present
 water quality of  the reservoir.

 H.   Lucal  Perception

 Several studies were undertaken over  the past few years  to evaluate the  conditions
of  the Ilillsborouyh River and Bay.  There  is  a tremendous interest  on the part
of  local professors,  local USGS offices and the Public Works Department  to
define the problem.

The USGS established  a stonuwater evaluation  program  in  1974.   That project
established  10 streamflow gaging stations,   12 recording  rain  gages and
tabulated watershed land  uses.  Runoff and  rainfall data,  and  water quality
data, has been collected  since 1975.

The University of South Florida,  College  of Engineering,  has performed several
hydraulic and hydrologic  studies in  an attempt to develop models  to simulate
the hydraulics of  the  Bay.

The Public Works Department  is concerned  with the quantity  as  well as quality
problems.  Tampa's relative  lack  of significant  topographical  relief, coupled
with a high  average annual rainfall,  has  necessitated the construction of
numerous  Sturm sewer  systems.   The majority of the systaiis  were constructed  well
before urban runoff was considered to be  a  possible source  of  water quality
problems. The City of Tampa has identified over 30U  drainage  problem areas  and
is concerned with  taking  care  of  these yet  satisfying the State standards.
                          PROJECT DESCRIPTION
A.   Major Objective

Goals of the Tampa urban runoff studies are to characterize the stonnwater
flows and loads from urban drainage basins, analyze the effectiveness of
selected stonnwater controls, determine the Impact of storm generated loads
on the lower Hillsborough River and develop a stonnwater management plan  for
the City of Tampa.  The stoniiwater management plan will address receiving
water quality, the quantity and quality aspects of stonnwater runoff, and
support the cities efforts to deal with flooding problems  in an environmentally
sound manner.

B.   Methodologies

Rainfall quantity and quality data will be collected  and  analyzed  to develop
design storms and storm sequences, and characterize the direct  load  input to
the drainage basins from rainfall.  Basins will be selected  for detailed
monitoring during storm events to assess rainfall-runoff  relationships  and
stonnwater flows and  loads.  Stonnwater controls will be  selected  and monitored
during storm events to assess  their effectiveness  in  reducing  stormwater  load-
ings.  Stormwater flows and  loads will be  determined  for  the entire  study
area under design conditions and used  in development  of  the  citywide storm-
water management plan.

A receiving water study will be on-going concurrently,  funded  by  the City
of Tampa.  This  study will consist of  a data  collection  effort intended to
better characterize water quality  in  the  lower  liillsborough  River  and analysis
of these  data  to determine the impact  of  stonuwater  runoff.   Specifically,
the data  collection effort will consist of continuous monitoring  of  stage,
tanperature, conductivity and  dissolved oxygen,  synoptic sampling  conducted
during distinct  hydrologic conditions, continued  collection  of long-term
background data, collection  of sediment oxygen  demand and sediment chemistry
data,  and biological  sampling.

 C.   Monitoring

 Equipment is  just  being  ordered.   It  is  anticipated that each site will  contain
 a precipitation  recorder and sampler, a  water level  recorder and an automatic
 sampler.

 D.   Controls

 Controls to be monitored have not been definitely selected.  The controls
 studied may include 1)  detention/retention basin with underdrain, 2) drainfield
 or trench, 3) open bottom inlet or catchbasin and 4) undercut ditch.
                                   GII-16
                                                                                                                               GH-17

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  NATIONWIDE URBAN RUNOFF PROGRAM

KNOXVILLE/KNOX COUNTY METROPOLITAN
       PLANNING COMMISSION

          KNOXVILLE, TN

          REGION IV, EPA
              G12-1

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                              INTRODUCTION
                                                                                                                         PHYSICAL DESCRIPTION
Knoxville, Tennessee Is  a  growing metropolitan area with a population of  some
182,000 persons living within  the present city limits.  Total  Knox County popu-
lation is approximately  335,000, while some 483,000 persons live within the
SMS A.

An earlier study of some urban streams in Knoxville revealed that urbanization has
a greater than expected  effect on the hydrological regimes of streams with large
amounts of carbonate rocks in  the basin.  Under rural conditions much of  the
streamflow is lost to the  carbonate rocks and solution channels and is not measured
as surface runoff.  Land cover alterations, along with sewers and channel  modifications
In the study watersheds, resulted in an increase in the peak of the unit  hydrograph
of from 1.9 to 3.6 times and a decrease in time to peak ranging from .86  to .36.

An important conclusion  of the previous study was the recognized need for additional
water quality monitoring across the flow regime.  Building on this original data base,
the Second Creek basin is  being studied.  Second Creek while typical  of other urban
streams in the area,  is  well recognized for its poor water quality.  The  Knoxville
Metropolitan Commission  and Tennessee Valley Authority hope to identify the cause
of these water quality problems and the solutions.
A.   Area

Knox County, located in eastern Tennessee, lies wholly within the Ridge and Valley
physiographic province of the southern Appalachian region, extending from 35°47'30"H.
to 36010'30"N. latitude, and 83°39'U. to 84°16'U. longitude.

The topography of the county consists of alternating ridges and valleys which cut
into the steeply dipping, folded and faulted calcareous rocks.  The rocks include
limestone, dolomite, calcareous shale, sandstone, and sandy shale.

Host soils have textures ranging from loam to silty clay loam. Depth to bedrock
ranges from zero to more that 20 feet.  Fifty-seven percent of the county has
a soil depth of more than five feet.

The study area is located in a broad valley between the Cumberland mountains and
the Great Smoky Mountains.  These two mountain ranges have a significant influence
upon the climate of the valley.  Topography has a pronounced effect upon the prevailing
wind direction.  Winds usually have a southwesterly component during day time,
while night time winds usually move from the northeast.

Rainfall is distributed throughout the year with a normal annual total of 47.98
inches.
                                                                                               B.   Population

                                                                                               The population of Knox County has grown significantly in the past 15 years.   Between
                                                                                               1960 and 1970 the county grew 10.3%, while between 1970 and 1975 it grew  9.8%.   Between
                                                                                               1975 and 1990 the county is projected to grow an additional 23.7%.  The following
                                                                                               table shows the population of the county.
                                                                                                                   Year

                                                                                                                   1960
                                                                                                                   1970
                                                                                                                   1975
                                                                                                                   1980
                                                  Population

                                                  250.523
                                                  276.293
                                                  303.900
                                                  335.400
                                                                                               C.   Drainage
                                                                                               There  are  five drainage basins within the Knoxville-Knox County  study  area  which,
                                                                                               by nature  of  their land use, may be considered urban.   These  include First  Creek.
                                                                                               Second Creek. Third Creek. Fourth Creek, and  Ten Mile Creek.  The  two  most  Intensely
                                                                                               developed  drainage basins. First Creek and Second Creek, were chosen for  this
                                                                                               study.  In combination, these two creeks drain the entire Knoxville central  business
                                                                                               district.
                                       G12-2
                                                                                                                                       G12-3

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First Creek Drainage Basin

The First Creek drainage basin encompasses an area of 22.04  square miles, the
largest 1n the Knoxvllle metropolitan area.  Seventeen percent of the area
(3.78 square miles) drains  into sinkholes.  These sinkhole areas arc primarily
In the north and northwest  parts of the basin.  The average  drainage density
of the First Creek basin Is nine miles of channel per square mile, with the
highest drainage density on steep slopes and less soluble geographic formations,
and lowest drainage density on gentle slopes and more soluble rocks.

Groundwater elevation  and permanent streams In the First Creek drainage basin
are shown on Figures 1 and  2.  The major trunk of First Creek runs from northwest
to southeast and Intercepts northeast - southwest surface and groundwater flows.
Inter - basin water transfer may occur where abundant sinkholes are present and
the surface drainage divide is not prominent.

In the First Creek drainage basin, commercial land use is concentrated on the
lower (downstream) portions of the basin and along the Broadway strip commercial
development.  Open and forest lands predominate In the northeastern portions of
the basin.  Although Industrial and multi-family land uses cover small portions
of the basin, single family residential land use Is Important.  Table 1 shows the
percentage of different land uses in the basin.

Areas of potentially high water yield are associated with steep slopes, high elevations,
shallow and less permeable  soils (low soil moisture capacity), s-hale bedrock,
faults acting as groundwater barriers, and densely developed residential and
commercial land uses which  have a large percentage of Impervious surfaces.  Areas
of potentially low water yield are related to deep and more  permeable soils, gentle
slopes, and carbonate  rocks where bypass losses of groundwater occur, especially in
summer and fall when soli moisture Is depleted.  In general  low water yield occurs
in summer and fall on  relatively low elevations, deep and more permeable soils, carbonate
rocks, and open and forested areas.

Second Creek Drainage  Basin

The Second Creek watershed  Is adjoined on the east by the First Creek basin and on
the west by Third Creek basin.  Second Creek basin Is elongated 1n shape and is
the smallest major drainage basin In the Knoxvllle urban area.  The creek originates
on Blackoak Ridge north of  Insklp and Norwood communities and drains into a gently
rolling area.  It has  no major tributaries unlike the other  principal streams In
Knoxville.  The creek  flows into central Knoxvllle through the gap In Sharps Ridge
where 1-75 (U.S. Highway 25W) and the Southern Railway pass  through.  Below the gap
it passes the Southern Railway's Coster Yards and is repeatedly crossed by the railway
before reaching downtown Knoxville.  The creek enters the Tennessee River at the
eastern edge of the campus  of the University of Tennessee.

The basin has a drainage area of 7.1 square miles (4,544 acres) Including an area
0.5 square miles (320  acres) that drains into sinkholes and  has no surface channels.
The complete drainage  basin is shown on Figure 3.  Drainage  density is high on
steep slopes and high-elevation areas, while low drainage density is associated
                                       G12-4
O  SURFACE DRAINAGE DIVIDE

•  GROUNDWATER DIVIDE
         FIRST  CR££K

      GROUNDWATER
     ELEVATION   MAP
                                                                                                                       Figure  1
                                                                                                                                    G12-5

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                                     :°oo°,po°°p
                                                            o
                                          TABLE 1

                            LAND USE IN FIRST CREEK DRAINAGE BASIN
                                                                                              Total
                Single Family  HuUI-Famlly   Commercial   Industrial    Open    Forest   Total   Impervlou:
Percent of total
area  («)

Extent (Acres)
   45

6,347
  6

846
  6

846
  1         28      14     100   .   17.5

141      3.949   1,975   14,104   2,468

-------
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                                                     with gentle slopes and low-elevation areas such as the Coster railway yard.   The
                                                     highest drainage density ocurs on Sharps Ridge, where the geologic  structure 1s
                                                     complex, rocks are tmperaeable and not highly soluble, elevation Is high, and
                                                     slopes are steep.

                                                     Elevations In Second Creek basin range mostly between 900 and 1,100 feet. The maximum
                                                     elevations are 1.360 feet on Blackoak'Ridge and 1.400 feet on Sharps Ridge,  both
                                                     on the divide between First and Second Creeks.  Along the divide between Second
                                                     and Third Creeks, the maximum elevations are 1,180 feet on Blackoak Ridge and 1,340
                                                     feet on Sharps Ridge.  The lowest elevation In the basin at the mouth of Second
                                                     Creek Is 810 feet.  The local relief Is 590 feet.

                                                     Second Creek basin Is more urbanized than First Creek.  Commercial  developments
                                                     are located downtown, along Central Avenue, and along Clinton Highway.  Industrial
                                                     use Is extensive from Western Avenue to the Coster yards of the Southern Railway.
                                                     Because of the greater extent of Industrial land and less open and  forested  lands
                                                     than in the First Creek basin, a higher percentage of impervious surfaces and
                                                     higher water yield occurs. Table 2 Indicates the percentage of different
                                                     land uses in the basin.

                                                     0.   Sewerage System

                                                     Storm sewers are used primarily to convey water to the nearest surface stream.
                                                     A few older homes have septic tanks, the remainder are served by sanitary sewers.
                     SECOND   CREEK

              DRAINAGE  NETWOF
Figure 3

 G12-8
                                                                                   G12-9

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cc
u
         O 01
         -i^
               IO   f—
               CM   CO
                             PROJECT AREA

I.    Catchment Name  - Rl  (Residential Site One)
     A.    Area - 54.24  acres.
     B.    Population -  578 persons.
     C.    Drainage - End-of-pipe site draining residential land use.  Main
          channel is 1600 feet.
     D.    Sewerage - Drainage area of catchment  is B9.92X separate storm
          sewers. 81.921 of this area has curbs and gutters and 18.062 has
          swales and ditches.  10.08X is not served by separate storm sewers.
     E.    Land Use
          46.17 acres (85X)  is 2.5 to 8 dwelling units per acre residential.
          4.04 acres (7«) is urban Institutional.
          1.41 acres (3S) Is urban parkland.
          2.62 acres (5X) is linear  strip development.
II.  Catchment Name  - SC  (Strip Commercial Site)
     A.    Area - 187.04 acres.
          Population -  464 persons.
                                                                                                B.
                                                                                                C.

                                                                                                D.

                                                                                                E.
              ii   £
          Drainage -  Drainage ditch draining strip commercial site.  Main
          channel  is  1330 feet.
          Sewerage -  Drainage area of catchment  Is 23.47X separate storm
          sewers.   100X of this  area has curbs and gutters.  76.53X of the
          area does not have separate storm sewers.
          Land Use
          1.08 acres  (U) is urban Institutional.
          65.40 acres (35X) is linear strip development.
          101.02 acres (54X) is  .5 to 2 dwelling units per acre residential.
          .18.8 acres  (10X) is <  5 dwelling units per  acre.
           .70acres (<1X) is 2.5 to 8 dwelling units  per acre.
                                   G12-10
                                                                                                                            G12-11

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III.  Catchment  Name - RS2 (Residential Site Two)

     A.    Area  - 89.34 acres.

     B.    Population - 333 persons.

     C.    Drainage - End-of-plpe site draining residential  land use.  Main
          channel Is 1600 feet.

     D.    Sewerage - 10M of the area has no separate storm sewers.

     E.    Land  Use

          66.40 acres (74%) Is .5 to 2 dwelling units per acre.

          3.40  acres (4X). is linear strip development.

          .70 acres (IX) Is 2.5  to 8 dwelling units per acre residential.

          18.8  acres (21X) Is <  .5 to dwelling units per acre residential.

IV.   Catchment  Name - CBD (Central Business District)

     A.    Area  - 25.8 acres.

     B.    Population - 0 persons.

     C.   Drainage - End-of-plpe site draining central business district.

     D.    Sewerage - 100X of the area is served by separate storm sewers.
          100X  of that area has  curbs and gutters.

     E.    Land  Use

          25.8  acres (lOOt) is Central Business District.
                                PROBLEM
A.   Local Definition
An earlier study of some urban streams in Knoxvllle revealed  that  urbanization
has a greater than expected effect on the hydrological  regimes  of  streams  with
large amounts of Carbonate rocks in the basin,  under rural conditions much  of
the streamfloM is lost to the carbonate rocks and solution channels  and  Is not
measured as surface runoff.  Land cover alterations, along with sewers and
channel modifications in the Study watersheds, resulted  in an increase in  the
peak of the unit hydrograph of from 1.9 to 3.6 times and a decrease  In time
to peak ranging from 0.86 to 0.36.  From a water quality standpoint, material
transport of most constituents from the basins was not  significantly greater
than that which has been previously reported for some rural watersheds.

This Knoxvllle, Tennessee urban study was conducted at  four watersheds located
in Karst terrain - - areas overlying soluble carbonate  rock.  Storm  sewers are
used In these study watersheds to convey stormwaters to  the nearest channel.
As a consequence, the hydrology of these study catchments proved to be quite
complex which served to provide some contrasts for evaluating and  quantifying
these urban systems.

Mathematical streamflow models which had been developed  earlier using data from
typical rural areas were modified to handle urban watersheds  and used in this
study to quantify the Impact of urbanization upon the hydrology of the study
watersheds.  The models were regionalized so that necessary parameters could
be predicted from watershed and climatic measures.

Based upon the model studies, urbanization was found to have  a  particularly
marked effect on water yield from catchments where, under rural conditions,
most of the potential  streamflow Is lost to the carbonate rock  drainage  system.
Increases in yield up to 270 percent were found in a watershed  where development
Is extensive.  Most of this increase results from storm runoff  that under  rural
conditions would have drained Into the carbonate rock system  and therefore bypassed
the gage site.  At one watershed where bypass losses were not a factor, modest
Increases in stormwater runoff resulted In a near-corresponding decrease in
groundwater runoff.

In the study, it was found that urbanization can affect the storm  hydrograph  In
two ways.  Through land cover alternations along with sewers  and channel changes,
the peak of the unit hydrograph was found to have been Increased at the study
watersheds by-factors ranging from 1.9 to 3.6.  The times to  peak  were decreased
by factors ranging from .86 to .36.  Increased stoni runoff from urbanization,
it was found, could further modify the unit hydrograph.

Bulk precipitation and water quality data collected at the project were compared
with data collected at other studies.  It was found that because much of the
potential runoff at two of the project watersheds was lost to the  carbonate  rock
drainage system these watersheds act as filters.  For most constituents the
loadings into the watersheds from the atmosphere exceeded the streamflow loadlngsr
                               G12-12
                                                                                                                              G12-13

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The concentrations and loadings of some metals were  found  to  be  well  in  excess
of recommended water quality criteria In two of the  project watersheds.   Hlgn values
for Iron and manganese that were found appeared to be  associated with erosion
problems.  Relatively high concentrations of lead were also found and the source
appeared to be the atmosphere.

The streamflow loadings of organic* and the concentrations of pathogenic Indicators
were found to be high from the study areas and reasonably  comparable  with urban
data collected elsewhere.

The most important conclusions from this study were  the following:

1)   The impact of urbanization upon the storm hydrograph  results from a com-
bination of land use/channel drainage changes and storm runoff changes

2)   Atmospheric sources may account for most of the loadings for many water
quality constituents, at least in watersheds with separate sewer systems

3)   There is a need for monitoring of water quality.   Water  quality  in  rural
and urban areas should be monitored across the flow  regime in order to be used
in the development of operational nonpoint source water quality  models and
identify pollution source information so that pollution control  money will  be
spent effectively and result in the greatest improvement in water quality.
solution to park maintenance.  Of even greater concern  is  the fact that the
creek constitutes such a public health menace due  to  the bacterial contamination
(State standards can be exceeded by many orders of magnitude during and after
a storm) that unless some remedial action Is taken, it  will  be necessary to
exert physical barriers to prevent even partial body  contact.

The Tennessee River Is actually the backwater of Fort Loudoun Reservoir as It
passes through Knoxvtlle and  is used as * drinking water source by downstream
communities (as well as Xnoxvllle) in addition to  such  recreational activities
as swimming, boating, fishing, etc.  Although a single  urban stream such as
Second Creek probably does not exert a severe impact  on the  river in and of
itself, the accumulated discharges of all of Knoxville's urban streams may well
exert considerable stress on  the assimilative capacity  of  the river and contribute
to its degrading water quality.  Although It will  remain for the NURP project to
provide firm quantification of these urban  runoff  loads, it  is conjectured that
their combined loading might  well be an order of magnitude'greater than that
of the sewage treatment plant when its upgrading  is finished in 1982.  Should this
prove to be the case, the need for better water quality management practices will
be even more acute since the  affected receiving water will include the reservoir as
well as the urban streams themselves.
8.   Local perception

The water quality problems typically found in Knoxville's  urban streams  can
be appreciated by the following general observation  of  conditions  in Second
Creek.  Portions of Second Creek are highly eutrophic — there are stream
reaches measured in hundreds of yards where the water surface is totally obscured
by rooted vegetation.  In other areas the stream is  replete with filamentations
and other types of algae and a host of slimes.  Evidence of streambank erosion
due to Increased runoff rates is abundant.  During storm events, the stream may  turn
absolutely black as it passes through the lower central ousiness district,  and
it produces a visible plume at its confluence point  with the Tennesse River that *
can last for many hours after a storm event and extend  downstream  for a
considerable distance.

The harshest indictment of Second Creek's present water quality has arisen  in
conjunction with the planned 1982 International Energy  Exposition  which  Knoxville
will host.  The six-month long event will occupy a site at the lower end of the
Second Creek basin, and initial plans were to integrate the creek  into the  site
design.  Residual plans for the Exposition site include a  public park with  a flow
through pond on Second Creek to serve as a focal point.  The degraded water
quality of Second Creek is so poor (including  such aesthetically important con-
siderations for a park as color and odor)  that Expo planners are considering ways
to hide the creek from attenders and are drilling wells as a source  for water to
maintain the pond during the course of the Exposition. Such an energy  and other
resource intensive alternative can hardly  be considered as a BMP or  long-term
                                    G12-14
                                                                                                                                G12-15

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                           PROJECT DESCRIPTION
A.   Major Objective

The purpose of the proposed project In Knoxville Is to examine the water quality
problems which result from nan's urban activities and to determine what manage-
ment practices might be Implemented to mitigate the present water quality
problems and prevent others front occurring as the area of urban development
expands.  The msjar objectives are the following:
     1)



     2)

     3)
            Determine  sources  of  pollutants  in  urban  streams  that  result  from
            storm  events  and threaten,  Impact or deny their designated  beneficial
            uses.

            To further characterize the urban stream  systems.

            To provide Increased confidence  In the transfer of data from gaged
            to ungaged catchments at the local,  State, Regional, and National
            levels.

      4)   To provide a better understanding of the influence of the geological
           features (karst terrain, carbonate rock)  on urban  runoff.

      S)   To provide  preliminary data on  BMP effectiveness  at a pilot  scale
           level.

 The primary emphasis of  the project is on the Second Creek basin, although  a
 small catchment located  in the First Creek  basin is  included to help establish
 the transferability of the data.

 6.   Methodologies

 An Intense  data collection effort will take place over a two year period to
 further characterize the  urban runoff loads and the  impact on the stream.
 The source of the pollutants,  their concentrations, and transport, and their
relationship to the runoff process will be described.

C.   Monitoring

Six sampling sites are included  In the study.   These  sites cover different
land  uses as well  as attempt to  characterize the karst terrain.   Following
is a  brief  description of the  equipment  available at  each of  the sites  listed.

                         Central  Business  District Site
                         Residential (Woodland Ave.)
                         Upper Sink
                         Lower Sink
                         Residential (Orchid Drive)
                         Strip Commercial
Central Business District Site

The CBO sampling site Is located at the Intersection of Central Street  and
Union Avenue.  Water sampling and flow measurement is performed In  the  outflow
pipe of a manhole.  A 30 inch Palrcer-Bowlus flume is Installed  In the outflow
pipe.  An (SCO model 1870 flow meter Is used in conjunction with the flume  to
measure and record flow.  Flow proportional water samples are collected during
rain events with an ISCO model 2100 automatic water sampler.  A wet/dry
atmospheric collector as well as a recording ralngage are located at the  site.

Woodland Avenue Residential Site

This sampling site is located near Woodland Avenue and Central  Street.  The
sampling is done in a drainage ditch tributary to Second Creek.  A  48  inch
Palmer-Bowlus flume has been  installed in the ditch.  An ISCO model  1700  flow
meter will be used to measure the flow going through the flume.  The totalized
flow values are recorded by an ISCO model 1/10 digital printer.  A  Friez  water
level- recorder will be used to obtain a continuous strip chart  record of  the
flow.  Flow proportional water samples are collected by an  ISCO model 2100
automatic water sampler.  A recording raingage and wet/dry  atmospheric  collector
are located at a residence adjacent to the sampling location.

lower Sink Site

The lower sink site is located just off Rowan Drive in a drainage ditch tributary
to Second Creek.  The data collected at this site is limited to flow data.  The
primary flow measuring device is 4 concrete control structure plus  a weir plate.
A rating curve Is being developed for the control structure.  A Friez water
level recorder is used to acquire a complete set of flow data.  The  site, which
is in a sink area, will be studied (using tracers) in conjunction with  the
upper sink site to accumulate data regarding subsurface drainage In  the area
of karst-terraln.  A raingage is located within the drainage area.

Upper Sink Site                                                                "'

The upper sink site Is located on Sanford Road, approximately two blocks  north
of the lower sink site.  The data collection at this site is also limited to
flow data.  The data collected at this site will be used in conjunction with    :
the data collected at the lower sink site to study subsurface drainage.  The
equipment is the same at the  two sites.

Orchid Drive Residential Site

The .Orchid Drive site Is located in a culvert next to the Midas Muffler Shop.
The primary flow measuring device is a 30 inch Palmer-Bowlus flume.  An (SCO
model 1700 flow meter Is used to measure flow.  The total flow values are
recorded by an ISCO model 1710 digital printer.  A modified Friez water level
recorder is used to obtain a continuous strip chart record of the flow.   Flow
proportional water samples are collected with an ISCO model 2100 automatic
water sampler.  A recording raingage and wet/dry atomospheric collector are
located in the upper part of  this drainage area.
                                  G12-16
                                                                                                                                G12-17 .

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Strip Commercial Site

The strip commercial site Is located in a drainage ditch behind the Clinton
Plaza Shopping Center.

A 54 Inch Palmer-Sowlus flume is Installed in the ditch.  An I SCO model 1700
flow meter Is used to measure the flow going through the flume.  An (SCO model
1710 digital printer records total flow values and a modified rriez aater
level recorder provides a continuous strip chart record of the flow.' A recording
raingage and wet/dry atmospheric collector is located in the drainage area.
Flow proportional water samples are collected by an ISCO model 2100 automatic
water sampler.

Tennessee Valley Authority is responsible for most of the technical work,
including sampling equipment installation and calibration, data collection, and
sample and data analysis.  Both composite and discrete samples will be taken.
It is hoped that composite samples will be collected from 16 storm and discrete
samples from 8 storms.

0.   Controls

The Best Management Practices which will be evaluated have not yet been
determined.  After preliminary sampling results are obtained, BMP's will be
selected and implemented at the various sites In order to evaluate their
effectiveness.
                                      G12-18

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     NATIONWIDE URBAN RUNOFF PROGRAM



TRI-COUNTY REGIONAL PLANNING COMMISSION



              LANSING, MI



             REGION V, EPA
                  G13-1

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                              INTRODUCTION
This project, with investigation conducted under the direction  of  the  Tri-County
Regional Planning Commission, is located in the City of  Lansing state  capital  of
Michigan.  Urban stonnwater pollution impacts are being  evaluated  in the  Bogus
Swamp Drainage District,  Ingharo County, which is drained by  stomi  sewers  into
the Grand Kiver.  The Grand River and its major tributaries  In  the vicinity of
Lansing, the Red Cedar and Sycamore River, flow eventually  into Lake Michigan.

The Grand River has been classified for total body contact  recreation  in  the reach
into which the Bogus Swamp stormdrain network flows.  Future planning  for the
Grand River includes fish ladders to allow fish migration,  and  development of  linear
parks, some of which already exist along the river, which is now used  for boating and
fishing, with other recreation activities conducted primarily at lake  Lansing.

The existing water quality of the Grand River was documented in recent monitoring
efforts.  Problems were identified as the result of (1)  point source discharges;
(2) combined sewer overflows; and (3) stomiwater drainage.   Nonpoint source-pollution
has been identified as a major contributor to biochemical oxygen demand,  nitrogen
and suspended solids.

Of concern to the local and regional agencies is the need to evaluate  the effec-
tiveness of best management practices that may be applied to reduce pollution  of
the Grand River.  This information will be utilized in future planning for the most
cost-effective total effort to reduce pollution from the three  identified sources.
Such future planning will also utilize similar data developed by other urban  runoff
projects underway nationwide to the extent it proves both transferrable and  applicable.
The project lias the major objective of evaluating an in-line wet storage basin, a
normally-dry detention basin, and two sections of increased diameter storm drains,
for both costs and stonnwater quality enhancement.
N
                                                                                                                     LAKE
                                                                                                                     MICHIGAN
        LAKE
        HURON

  'ANN ARBOR
        LAKE
        ERIE
                                                                                                                                        STATE  LOCUS
                                                                                                                                 MICHIGAN  NURP PROJECTS

                                                                                                                                         FIGURE 1
                                         G13-2
                                                                                                                                         G13-3

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            UNITED STATES
    DEPARTMENT OF THE INTERIOR
         GEOLOGICAL SURVEY
84'37'30"         |^y»k.L             *U?JS- " *W
                                                           GRAND
    -oK-xwv^-    >'
...t'sj'.vs&tfr	r  -..
                 LAtlSING STREETS,  USGS QUAD SHEET
                  SAMPLING AND MONITORING POINTS
                             FIGURE  2
                             G13-4
                                                       Station Description and Schedule
                                                            Located In  the Bogus Swamp Drain District are three types of
                                                       Best Management Practices  (BMP's)  for the control of  storrnwater
                                                       pollution.  These are (a) two in-line upsizcd tiles, (b) an in-line retention
                                                       basin,  and (c)  an off-line  detention basin.    Figure I  illustrates
                                                       monitoring stations and the "Best Management Practices" (BMP's) being
                                                       studied and includes all station locations and designations in Table I.
                                                       Each  will be  monitored  for flow and stormwater constituents to
                                                       determine the efficiency and cost effectiveness  for the reduction of
                                                       various pollutants.  Sampling  at the inlet and outlet of each BMP will
                                                       require a  total of ten  stations, each consisting of flow recorders and
                                                       samplers.
                                                                                                            TABLE  I.  STATION DESCRIPTION
                                                                                                                                                  BMP Type
1
2
3
4
5
6
7
8
9
10
Main Outlet
West Subdistrlcl Drain
Dryer Farms Detention Pond
- outlet
- Inlet
Golf Course Pond Retention Pond
- outlet
- Inlet '
Upsized tile 96" Sump
- outlet
- Inlet
Upslzed tile 96" Sump
- outlet
- Inlet
                                                                                         11
                                                                                                  River
                                                                                                                        G13-5

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                                                                                                                                 PROJECT AREA
                          PHYSICAL DESCRIPTION
A.   Area

     The City of Lansing Michigan,  in  Ingham County, is located in the north central
     lower peninsula.   The  Bogus  Swamp Drain Drainage District, in which the best
     management pratices are  installed,  is west of, contiguous to, and representative
     of developed urban conditions  in  Lansing.  The drainage district contains 450
     acres.  Land uses and  land covers in this district are separated into more or less
     homogeneous covers which correspond to drainage subdistricts.  Uses include
     single and multi-family  residential, commercial, and industrial, as well as open
     space-recreation.

B.   Population

     The 1971 population of Lansing-East Lansing was 385,694, with a projected 1980
     population (Series E,  1972 OBERS) of 434,000.  The 1980 census for the Lansing
     SMSA reported an  actual  population  of 468,482, and 130,414 within the Lansing
     city limits.  The 1972 OBERS projection shows that the 1980 SMSA population was
     not anticipated to be  reached  until 1985, which is an indication of the rate of
     urbanization in the area.

C.   Drainage

     The drainage district  terrain  is  typical Michigan glacial landscape with gently
     rolling topography and relatively low slopes.  The surface elevation drops 20
     feet, from 890 feet at the headwaters to 870 feet at the Grand River outlet.
     Urbanization has  Increased the impervious cover to the extent that the capacity
     of many storm sewers Is  routinely exceeded by storniwater flows.

     The Grand River headwaters are located south of Lansing, and with its tributaries
     drains approximately 2/3 -3/4  of  Jackson County, most of Ingham County, and a
     small part of Eaton County on  its way north through Lansing.  From there it
     flows generally West-northwest until  it enters Lake Michigan in Ottawa County.

0.   Sewerage Systan

     Within the drainage district,  the storm and sanitary sewers are separate, except
     for possible illegal connections  not yet detected.  Within the City of Lansing,
     there are areas served by combined  sewers which result in high levels of coliform
     in the Grand River, preventing body contact recreational uses.  Correction of the
     combined sewer overflow  problem will be incorporated into a combined total
     pollution reduction effort that includes application of best management practices
     to control urban  stormwater  pollution, and control of point source discharges,
     in the most effective  manner.   Such planning will be accomplished when results
     of the Nationwide Urban  Runoff Program projects become available.
1.   Catchment Name - HI 1,001, Bogus Swamp Drain

     A.   Area - 452.6 acres

     B.   Population - 2250 persons.

     C.   Drainage - Subsurface conveyance to the Grand  River.  Main  channel
          Is 49,500 feet at a slope of approximately  32  feet  per mile.

  •   D.   Sewerage - Drainage area of catchment is  1001  separate storm  sewers.
          Forty-nine percent Is served by curbs and gutters,  and Sit  is served
          by swales and ditches.

     E.   Land Use

          126.5 acres (28%) Is 0.5 to 2 dwelling units per acre urban residential.
          of which 37.4 acres (30%) Is Impervious.

          76.9 acres (171) Is 2.5 to 8 dwelling units per acre urban  residential,
          of which 23.4 acres (30%) Is Impervious.

          14.3 acres (3%) is > 8 dwelling units per acre urban residential.
          of which 8.3 acres (58%) is Impervious.

          13.2 acres (2.9%) Is Linear Strip Development,
          of which 10.1 acres (78%) Is impervious.

          10.1 acres (2.2%) is Shopping Center,
          of which 10.1 acres (100%) is Impervious.

          3.3 acres (0.7%) Is Urban Industrial (light).
          of which 2.2 acres (67%) Is impervious.

          83.2 acres (18.4%) Is Urban Industrial (heavy).
          of wlch 52.7 (63%) is Impervious.

          91 acres (20.1%) Is Urban Parkland or Open Space.
          of which 5.6 acres (6%)  is Impervious.

          Approximately 37% Impervlousness 1n entire catchment area.

II.   Catchment Name - MI 1.002. Bogus Swamp Drain

     A.   Area - 63 acre's.

     B.   Population - 0 persons (industrial).

     C.   Drainage - This catchment area has a representative catchment slope
          of 132 feet/mile, and 100% curbs and gutters.  The storm sewers
          approximate a 31 feet/mile slope, anil extend 9.450 feet.
                                      G13-6
                                                                                                                                      G13-7

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     D.    Sewerage  -  Drainage area of the catchment Is 100% separate storm
          sewers, and Is completely provided with curbs and gutters.

          Streets consist of  17 lane miles of asphalt all In fair condition
          and 2.2 lan.i miles of concrete, all In good condition.

     E.    Land Use

          63 acres  (IOCS) Is Urban Industrial (heavy),
          of which  40.4 (64%) Is Impervious.

III.  Catchment Name - HI l.DRO, Bogus Swamp Drain

     A.     Area - 127.6 acres.

     B.    Population  - 550 persons.

     C.    Drainage  -  This catchment area has. a representative slope of 121
          feet/mile,  37% served with curbs and gutters and 63% served with
          swales and  ditches.  The storm sewers approximate a 27 feet/mile
          slope, and  extend 10,650 feet.

     D.    Sewerage  -  Drainage area of the catchment Is 100% separate storm
          sewers.

          Street consist of 10.6 lane mile of asphalt, 59% of which Is In
          good condition and 41% of which Is In fair condition, and 6 lane
          miles of  concrete, 54% of which Is In good condition, and 46%
          of which  Is 1n fair condition.

     E.    Land Use

          52.9 acres  (41.5%) Is 0.5 to 2 dwelling units per acre urban residential,
          of which  16.1 acres (30%) Is impervious.

          5.2 acres (4.1%) Is > 8 dwelling units per acre urban residential,
          of which  3.1 acres (60%) is Impervious.

          8.4 acres (6.6%) Is Linear Strip Development,
          of which  4.9 acres (58%) Is Impervious.

          10.1 acres  (7.9%) Is Shopping Center,
          of which  10.1 acres (100%) Is Impervious.

          49.2 acres  (38.6%) is Urban Parkland or Open Space,
          of which  1.2 acres (2%) 1s impervious.

          1.8 acres (1.4%) Is Urban Institutional,
          of which  1.7 acres (94%) Is impervious.

          Approximately 29% impervlousness In entire catchment area.
                                   G13-8
IV.  Catchment Name - HI  l.DRF,  Bogus Swamp Drain

     A.   Area - 112.7 acres.

     B.   Population - 480 persons.

     C.   Drainage - This catchment  area has a representative slope of 233
          feet/mile, 42%  served  with curbs  and gutters and 58% served with
          swales and ditches.  The storm sewers approximate a 32 feet/mile
          slope, extending 9,980 feet.

     D.   Sewerage - Drainage  area of the catchment Is 100% separate storm
          sewers.

          Streets consist 10.1 lane  miles of asphalt,  of which 62% Is In good
          condition and 385 is in fair  condition, and  5.8 lane miles of concrete,
          54% of which is in good condition, and 46% of which is In fair
          condition.

     E.   Land Use

          38.0 acres 33.7% Is  0.5 to 2  dwelling units  per acre urban residential,
          of which 13.4 acres  (35%)  is  Impervious.

          5.2 acres (4.6%) is  8  dwelling units per acre urban residential,
          of which 3.1 acres (60%) is Impervious.

          8.4 acres (7.4%) is  Linear Strip  Development,
          of which 4.9 acres (58%) Is Impervious.

          10.1 acres (9%) is Shopping Center,
          of which 10.1 acres  (100%) Is Impervious.

          49.2 acres (43.7%) Is  Urban Parkland or Open Space,
          of which 1.2 acres (2%) Is impervious.

          1.8 acres (1.6%) Is  Urban  Institutional,
          of which 1.7 acres (94%) is Impervious.

          Approximately 31% imperviousness  In the entire catchment area.

V.   Catchment Name - MI  l.GCO,  Bogus Swamp Drain

     A.   Area - 67 acres.

     B.   Population - 340 persons.

     C.   Drainage - This catchment  area has a representative slope of 200
          feet/mile. 48%  sered with  curbs and gutters, and 52% served with
          swales and ditches.  The storm sewers approximate 29 feet/mile
          slope, extending 5,480 feet.
                                                                                                                                  G13-9

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     D.    Sewerage  -  Drainage  area of this catchment is 100% separate storm
          sewers.

          Streets consist of 6.6 lane miles of asphalt, all  in good condition,
          and 3.0 lane miles of concrete, 37% in good condition and 63% fair
          condition.

     E.    Land Use

          15.0 acres  (22.4%) is 0.5 to 2 dwelling units per  acre urban residential,
          of which  7.3%  acres  (49%) is impervious.

          5.2 acres (7.8%)  is  > 8 dwelling units per acre urban residential,
          of which  3.1 acres (60%) is impervious.

          10.1 acres  (1S.1%) is Shopping Center,
          of which  10.1  acres  (100%) is impervious.

          36.7 acres  (54.8%) is Urban Parkland or Open Space,
          of which  0.6 acres (2%) is impervious.

          Approximately  31% impervlousness in the entire catchment area.

VI.  Catchment Name - HI 1.GC1, Bogus Swamp Drain

     A.    Area - 30.3 acres.

     B.    Population  - 340  persons.

     C.    Drainage  -  This catchment area has a representative slope of 121
          feet/mile,  completely served with curbs and gutters.  The storm
          sewers approximate 22 feet/mile slope, extending 4800 feet.

     D.    Sewerage  -  Drainage  area of this catchment is 100% separate storm
          sewers.

          Streets consist of 6.1 lane miles of asphalt, all  in good condition,
          and 3 lane  miles  of  concrete, of which 37% in good condition and
          63% is in fair condition.

     E.    Land Use

          15.0 acres  (47.5%) is 0.5 to 2 dwelling units per  acre urban residential,
          of which  7.3 acres (49%) is impervious.

          5.2 acres (17.2%) Is > 8 dwelling units per acre urban residential,
          of which  3.1 acres (60%) Is Impervious.

          10.1 acres  (33.3%) is Shopping Center.
          of which  10.1  acres  (100%) Is impervious.

          Approximately  68% imperviousness in the entire catchment area.
                                  G13-10
VII. Catchment Name - HI 1.UP1, Bogus Swamp Drain

     A.   Area - 163.9 acres.

     B.   Population - 850 persons.

     C.   Drainage - This catchment area has a representative slope of  226
          feet/mile, with 21.0% curbs and gutters, and 79.0% having swales
          and ditches, the total extending 15,530 feet.

     D.   Sewerage - Drainage area of the catchment Is 100% separate stonn
          sewers.

          Streets consist of 14 lane miles of asphalt which are all In  fair
          condition, and 1.7 lane miles of concrete roadways, all  In good
          condition.

     E.   Land Use

          29.3 acres (17.9%) is 0.5 to 2 dwelling units per acre urban  residential,
          of which 6.5 acres (22%) is impervious.

          61.6 acres (37.6%) is 2.5 to 8 dwelling units per acre urban  residential,
          of which 16.1 acres (26%) Is Impervious.

          0.6 acres (0.4%) Is Linear Strip Development.
          of which 0.6 acres (100%) Is impervious.

          16.4 acre (10%) Is Urban Industrial (heavy)
          of which 12.3 acres (75%) is impervious.

          33.2 acres (20.3%) in Urban Parkland or Open Space,
          of which 0.6 acres (2%) Is Impervious.

          22.8 acres (13.9%) Is Urban Institutional,
          of which.8.7 acres (38%) Is impervious.

          Approximately 26%  Impervlousness In the entire catchment area.

VIII.  Catchment Name - HI 1.UP2, Bogus Swamp Drain

     A.   Area - 74.9 acres.

     B.   Population -  370 persons.

     C.   Drainage - This catchment area has a representative slope of  194
          feet/mile, with 47% having curbs and gutters, and 53%  having
          ditches and swales, the total extending 9,230 feet at  a  repre-
          sentative slope of 63 feet/mile.

     D.   Sewerage - Drainage area of the catchment  is  100% separate  storm  sewers.

          Streets consist of 8.9 lane miles of asphalt, all in fair condition.
          and 1.7 lane miles of concrete, all in good condition.
                                                                                                                                    G13-11

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E.    Land Use

     1.8 acres  (2.n)  Is  0.5 to 2 dwelling units acre urban residential,
     of which  1.3 acres (721)  Is Impervious.

     33.9 acres (45.3%) is  2.5 to B dwelling units per acre urban residential,
     of which  5.5 acres (16X)  Is Impervious.

     16.4 acres (21.92) Is  Urban Industrial (heavy)
     of which  12.3 acres  (751) 1s Impervious.

     22.8 acres (30.41) Is  Urban Institutional,
     of which  8.7 acres (381)  Is Impervious.

     Approximately 37X Impervlousness  In the entire catchment area.
                                PROBLEM
A.   Local definition (government)

     [he present water quality of the Grand River is capable of supporting a fishery
     in pike, bass, catfish and bluegill.  Contact recreation use is denied nrlmarly
     due to the high levels of coHfonn In the river, which come from the combined
     sewer overflows in the area, although none are Included in the catchment areas
     being evaluated in this project.

     Water quality problems have been Identified as also resulting from agricultural
     runoff, benthal demand, and urban runoff.  The problems experienced include
     high nutrient levels and cutreplication and low dissolved oxygen.  The principal
     water supply source is ground  water, causing concern of possible contamination
     from urban runoff, or the feasibility of using stonnwater for recharge, from
     the Red Cedar River, which is  underlain by sand/gravel.

B.   Local Perception (public awareness)

     llitti the exception of boating  and fishing, most residents travel to Lake Lansing,
     which is used as the principle local recreational  water body in the area.  They
     ate aware of the current unsuitability of the Grand River for body contact
     recreation. As the linear parks along the river continue to be developed, increased
     interest in the utilization of the river for recreation may be expected.
                                G13-12
                                                                                                                           G13-13

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                          PROJECT DESCRIPTION
     Major objectives
     Previous studies  conducted  in  the Lansing, MI, area have resulted in the conclusion
     that water quality  problems do exist in the Grand River which impair desired bene-
     ficial  use.   Further,  urban nonpoint source pollution has been identified as a
     major contributor to biochemical oxygen demand, nitrogen, and suspended solids.
     This study is designed to determine the efficiency of three best management practices
     to enhance storm  water quality from urban runoff.  The three best management
     practices consist of an in-line wet storage basin, a dry detention basin, and
     two up-sized sections  of underground storm drain pipe.

     Specific study objectives  include:

     1.   Determination  of  pollutant loads transported in the stormwater,
          as it enters and  leaves each best management practice structure,
          and related  land  use;

     2.   Assessment of  the impact  these practices can have on the receiving
          water quality  in  the project area and regionally;

     3.   Identification of the  financial requirements for capital and
          operating and  maintenance costs for these types of controls,
          and;

     4.   Transfer of  the  information developed to other agencies in
          the region,  for their  use in implementation of pollution control
          plans.

B.   Methodology

     Atmospheric deposition sampling is providing Information on the atmospheric input
     of pollutants under both wet and dry conditions.  The quantity and quality of flow
     into and out of the best management practices control features are being determined
     during storm event  conditions  through appropriate measuring and analytical procedures.
     Sediments collected in the  wet retention basin and the up-sized stormdrain sections
     are also scheduled  for analysis.

     The two up-sized  pipe  sections were installed with crown elevations at the same
     elevation as the  smaller diameter inlet and outlet pipes.  This resulted in standing
     water depth above the  pipe  inverts of 36 and 42  inches.  This design will provide
     conditions favorable to sedimentation for storms which occur frequently during the
     year.  To prevent flushing  of  deposited solids during high peak flows, periodic
     removal of the accumulated  sediment will be evaluated with respect to timing and
     cost.

C.   Monitoring

     Field sampling of runoff water quality, flow and precipitation, initiated in
     April, 1980, at some of the monitoring stations, has gradually been extended
     to all the stations, as construction activites were completed, and other
     problems encountered were eliminated.

                                      G13-14
Monitoring locations are identified In Figure 2.  Water quality  and  flow data
for inlet and outlet flows and in the Grand River are being obtained from ENCOTEC,
a consulting firm located in Ann Arbor, HI.  In addition  to the  11 locations
identified, a monthly grab sample is obtained at each of  the two stations
(one located upstream and one located downstream of Lansing) sampled by the
Michigan Department of Natural Resources.  These particular samples  are needed
for analysis of those parameters not being evaluated by the state which are
of interest in this program.  Two sampling locations have been established for
bulk fallout, and dryfall/wetfall sampling, with respect  to evaluating  the
atmospheric pollutant contribution.

The list of parameters and constituents examined in the sample collected includes:
total solids, total suspended solids, pll, total alkalinity, specific conductance,
choride, turbidity, total organic carbon, ammonia nitrogen, nitrate  plus nitrite
nitrogen, soluble and total Kjeldahl nitrogen, soluble and total  organic carbon,
soluble total phosphorus, orthophosphate, grease and oil, biochemical oxygen
demand, chemical oxygen demand, total metals-to include lead, iron,  zinc, chromium,
copper, nickel, cadmium, mercury and arsenic. PCB, total  fluoride, orthophosphate,
phenolics, sulfide, a pesticide scan, and particle distribution.

Equipment

The sites will be monitored using automatic flow recording devices of a type suitable
for specific installation, and automatic discrete/composite water samplers, except
for grab sample points in the Grand River.  Metfall and dryfall  sampling is also
done using automatic sampling equipment.  Sediments removed from the best management
practice control structures will be subjected to particle size analysis.

Control

the four best management practices structures will be evaluated  to determine their
effectiveness as control measures to reduce the pollutant effect  of  urban stormwater
runoff.
                                G13-15

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      NATIONWIDE URBAN RUNOFF PROGRAM

SOUTHEAST MICHIGAN COUNCIL OF GOVERNMENTS
         OAKLAND COUNTY, MICHIGAN

               DETROIT, MI

              REGION V, EPA
                  G14-I

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                              INTRODUCTION
The Southeast Michigan Council of Governments project  Is centered  In the
City of Troy, In Southeast Michigan,  about 15 miles  northwest of Detroit.
Topography in the area Is very flat,  with poor drainage.  Drains carry
runoff to the Clinton River and then  to Lake St.  Clalr.

The Clinton River, not specifically assigned a classification by name, must,
as a minimum, be protected for agricultural  uses, navigation. Industrial
water supply, public water supply at  the point of Intake, warmwater fish,
and partial body contact recreation.   As one of the  site selection criteria,
the'sub-drainage area identified as the Red  Run sub-basin, which exhibited
poor known stormwater-lnduced quality, was chosen.

Other siting criteria used In selecting Troy were, the requirement for an
area of poor drainage, yet highly urbanized  and within close proximity to
a concentration of raingages.  The exIrene southeast corner of Oakland County
is very flat, and has experienced rapid urbanization,  both factors exacer-
bating the problem that flat terrain  causes  for stormwater runoff.  This
area has also become highly urbanized during the past  20 years, and
Southeast Michigan Council of Governments has a raingage network In the
area.  Troy's population has Increased  approximately 350X since 1960.

As municipal and industrial wastewater treatment has reduced the degree or
level of pollution attributable to point source pollution, an Increasing
awareness has developed regarding the significant contribution from nonpolnt
sources, especially in southeast Michigan.  SEMCOG studies have identified
urban stormwater runoff as an important factor in water quality degradation.
                                                                                                                  LAKE
                                                                                                                  MICHIGAN
      LAKE
      HURON

'AHH ARBOR
      LAKE
      ERIE
                                                                                                                                       FIGURE 1
                                      G11-2
                                                                                                                                       G14-3

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                          PHYSICAL DESCRIPTION
A.   Area

The City of Troy, located in Oakland County, Is about 15 miles lo the northwest
of Detroit, or about 5 wiles southeast of Pontlac. Michigan.   The total  area
of the city comprises about 31 square miles.  Land use within the city is best
characterized as residential and commercial development.

B.   Population

Troy has experienced very large Increases in population over the last twenty
years from about 19.100 in 1960 to about 67.100 in 1980.  During this same
period. Oakland County has increased from about 668.800 to 1.011.793. a 51.3
percent increase.  The rate of increase in population for Troy was 106.8X from
1960 to 1970. and 70.ZX from 1970 to 1980.  Although the rate of increase has
slowed, it is reasonable to expect that the population will continue to grow
in the future.  The year 2,000 projected population  is 70.800.

C.   Drainage

The southeastern area of Michigan, including the City of Troy. Is very flat.
As a result  it  is poorly drained.  Drainage is accomplished through  storm drains
which connect to the Clinton River and  its  tributaries, which flows  into
Lake St. Clair.  Developments are required  to  Include detention basins to slow
storm runoff  and prevent downstream  flooding.

0.   Sewerage System

The existing  seweraye  system  is completely  separate, with  suitable treatment  of
the collected sanitary sewage, and discharge of  the  effluent.
                                       G14-4
N
          MAJOR RIVER BASINS IN SOUTHEAST MICHIGAN
                                                                                                                                CLINTON RIVER BASIN

                                                                                                                                      FIGURE 2
                                                                                                                                       G14-5

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OAKLAND COUNTY COMMUNITIES

         FIGURE 3
         011-6
                                                                                                 PROJECT AREA


                                                                   I.   Catchment Name - HI 2,  Catchment 100. VILLAGE GREEN

                                                                        A.   Area - 55.1 acres.

                                                                        B.   Population - 275 persons.

                                                                        C.   Drainge - This catchment area has a representative slope of 53.0
                                                                             feet/mile, 3.8X served with curbs and gutters.  The storm sewers
                                                                             approximate a 25 feet/mile slope and extend 2675 feet.

                                                                        D.   Sewerage - Drainage area of the catchment Is 75X separate storm
                                                                             sewers and 28% with no sewers.

                                                                             Streets consist of 1.05 lane-miles of asphalt, 100X of which Is In
                                                                             good condition.

                                                                        E.   Land Use

                                                                             2.8 acres (5.IX) 1s > 8 dwelling units per acre urban residential.
                                                                             of which 1.8X acres (64.3X) Is Impervious.

                                                                   II.  Catchment Name - HI, 200. BEAVER TRAIL

                                                                        A.   Area - 127.3 acres.

                                                                        B.   Population - 1.053 persons.

                                                                        C.   Drainage - This catchment area has a representative slope of 53
                                                                             feet/mile, 100X served with curbs and gutters.  The storm sewers
                                                                             approximate a  13 feet/mile slope and extend 3.300 feet.

                                                                        0.   Sewerage - Drainage area of the catchment Is  100X separate storm
                                                                             sewers.

                                                                             Streets consist of 7.74 lane-miles of concrete, 100X of which  Is  In
                                                                             good condition.

                                                                        E.   Land Use

                                                                             106.9 acres (84X)  Is 2.5 to 8 dwelling units  per acre urban residential,
                                                                             of  which  12.3  acres (9.7X)  is  impervious.

                                                                             20.4 acres  (16%)  Is Urban Parkland or Open Space.
                                                                                                           G14-7

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111.  Catchment Name - MI  2.  300,  SYLVAN  GLEN

     A.    Area - 97 acres.

     B.    Population - 459 persons.

     C.    Drainage - This catchment  area has  a  representative slope of  53
          feet/mile. 100* served  with curbs and gutters.   The storm sewers
          approximate a 29* feet/mile slope and extend  3,910 feet.

     D.    Sewerage - Drainage area of the catchment  is  81.2% separate storm
          sewers.

          Streets consist of 4.96.lane-miles  of concrete,  100* of which is in
          good condition.

     E.    Land Use

          78.8 acres (81.2%) is 0.5  to 2 dwelling  units per  acre urban  residential,
          of which 9.5 acres (125!) is impervious.

          18.2 acres (18.82) is Urban Parkland  or  Open  Space.

IV.  Catchment Name - MI 2, 400.  CITY Of TROY.  RECORDING RA1N6AGE

     A.    Area - 279.4 acres.

     B.    Population - 1,787 persons.

     C.    Drainage - This catchment  area has  a  representative  slope of  53
          feet/mile, 100X served with curbs  and gutters.  The  storm sewers
          approximate a 22.3 feet/mile slope  and extend 9,885  feet.

     D.    Sewerage - Drainage area of the catchment  is  79* separate storm
          sewers.

          Streets consist of 1.05 lane-miles of asphalt, 100%  of which  is  in
          good condition.   In addition there are about  12.6 lane-miles  of
          concrete, of which 1002 is in good condition.
                                PROBLEM
A.   Local Definition  (Government)

SEMCOG  identified stonnwater generated pollution as a problem  within  their
area of jurisdiction during the  initial Section 208 planning work.  Earlier,
stonuwater quantity problems had resulted  in requirements  for  runoff  control
in subdivision developments to prevent downstream damage.   In  the rapidly
urbanizing areas in southeastern Michigan, the topography  is relatively  flat,
and poorly drained.  Many stormwater detention basins have  been constructed
in compliance with quantity control requirements.  Such basins might  be  suit-
ably adapted through minor modifications to incorporate water  quality control.
This would eliminate potential water quality standards violations to  the
Clinton River drainage network, and denial of beneficial uses, if it  proved
cost-effective.

B.   Local Perception  (Public Awareness)

Public participation during the Initial planning effort which  identified
urban storuiwater runoff as a source of pollutants alerted  the  public.to
the problem.  Continued communications with local elected officials and
citizen leaders during the conduct of the NURP study has been  a require-
ment, and scheduled task in the work plan.  In addition, there is a public
education program task included in the detailed plan, designed to educate
the public before management recommendations are formulated.
                                       GIB-8
                                                                                                                                       G14-9

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VILLAGE
 GREEN
k
      nut
            SOUHE LUC
               LOU me
               TR
             Hints
                        »" »tm«
                       SYLVAN
                        GLEN
                        S.ITE
                                  0
                        1011
             .„
                                   1010
                                   «0»0
                                   RAIN  GAUGE
                                   IOIQ
                                  •Dig
                                                         BEAVER
                                                          TRAIL
                                                          SITE
        TROY,   MICHIGAN

      GENERAL  LOCATION  MAP
                  FIGURE 4
                                                                                                   PROJECT DESCRIPTION
                                                                          A.   Major Objective
The Oakland  County project, as a continuation and follow-up Section 208 study,
has been designed to evaluate the effectiveness of modified stonnwater
quantity control structures for use  In event runoff quality control.  In
addition to  this technical evaluation, the costs Involved for  the modifi-
cations, and subsequent maintenance  costs and responsibilities will be
reported. Legal and institutional aspects of an Implementation program will
be reviewed  and recommendations presented concerning needs in  these areas.

The project  will extend over three years, with Initial  sampling and monitoring
designed to  determine the level of pollution existing In the selected drainage
areas.  Subsequent sampling will demonstrate the effectiveness of detention
basin modifications In controlling the identified pollutants.

B.   Methodology

The hypothesis being tested is that  stormwater pollution control in newly
developing areas can be achieved with relatively Inexpensive modifications
over present practices, specifically retention systans, used In control of
stonnwater quantity.

Consultant testing and evaluation require sampling of rainfall and urban
runoff quantity and quality and engineering analysis of data.  The engineering
analysis Is  being performed to determine mass emissions of pollutants and the
degree to which various retention structures and modifications to these
structures reduce pollutant discharges.  General pollutants of concern are
suspended solids, oxygen demanding materials, toxics, and plant nutrients.

Studies concerning operation and maintenance requirements, both institutional
and legal constraints and alternatives for implementation, and evaluation of
overall costs and benefits are being conducted by SEMCOG, running concurrently
with the sampling/engineering effort.  Thus, the feasibility of using retention
structures as a best management practice (BMP) for controlling stormwater
runoff pollution In urban areas will be based on technical, legal, insti-
tutional, and economic considerations.

Information  generated will be used by SEMCOG in conjunction with relevant
work products from SEMCOG's 208 water quality management planning efforts to
determine the relative costs and benefits and the institutional constraints
Involved in  modifying existing stormwater quantity control systans for in-
corporation  of permanent  in-place stormwater quality control.  In particular,
design criteria and guidelines will  be prepared by the consultant for use by
local and nationwide site planners,  engineers, and review agencies to In-
corporate and Implement preventive control measures for urban  nonpoint pollu-
tion.  Results will also aid SEMCOG  In the development of future basin-wide
alternatives for controlling total urban pollutant loadings to the region's
rivers.
                    G14-10
                                                                                                                G14-H

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The proposed effort in Southeast Michigan lias  been organized  in conjunction
with the Oakland County Drain Commissioner in  order to  incorporate  the ex-
perience gained by the Cannes loner through his successful  administration of
programs to enforce the Soil  Erosion and Sedimentation  Act  (PA 347) and the
Plat Act (PA 288). both of which often require stoniiwater  retention basins.
The Drain Commissioner's function is especially important  to  the long-term
development of sound and comprehensive water resources  management since it
is the policy of SEMCOG to integrate a system  of  controls  for urban nunpoini
pollution into the present framework of laws and  practices, wherever possible.

The retention control measures to be assessed  in  this project are those re-
quired under Michigan PA 208  of 1967.  These controls are  required  in order
to reduce excess runoff from  development sites which are tributary  to county
drains with little additional hydraulic capacity.   Retention  structures are
designed to protect against the ten-year storm event.   Should these struc-
tures provide significant improvement in water quality, it may be possible
to implement a comprehensive  storm drainage program which  provides  both flood
protection and water quality  benefits.

Many variables affect the treatment efficiency of retention basins.  For
instance, three major variables affect the efficiency of a  basin for settl-
ing nut particulates; these are: (1) Influent  particle  size distribution.
121
(2) magnitudes and timing of water flow,  and (3)  basin configuration.   In
turn, these first two variables are a function of rainstorm  intensity,  ante-
cedent dry periods, drainage area land cover/use  characteristics  (e.g., soil
types, percent impermeable area, seasonal  activities,  slope), and  the design
and efficiency of the stoniiwater conveyance systen.

Previous SEMCOG studies have focused on the problem  of characterizing runoff
pollutant loads from different land uses.   Fran these  efforts,  it  has been
concluded that pollutant load characteristics of  runoff from commercial and
residential areas differ significantly.  Hence, the  kinds  of control measures
necessary to abate stonnwaten-associated  water pollution may vary  according
to the land use in the storm drainage district.  Accordingly, this project
considers two categories of land use:  residential and commercial.

Seventeen runoff events are projected to  be sampled  over the course of  the
project.  Ideally, two of these events will be snowmclts with one  sampled
early each Spring.  The remaining events  will be  rainfall  events.

C.   Monitoring

Three test sites have been selected for the purposes of this project.   Two of
the sites are residential and one is commercial.   All  arc  less  than 135 acres,
have curbs and gutters, and exemplify typical development  in many  areas of
the nation.  Their descriptions follow:

The Beaver Trail Sub. No. 2 and 3 retention basin is located off Pasadena
near Traverse.  The basin is in good condition with  some weed growth at
the northerly end due to wet conditions at the two 54-inch inlets.  Ex-
isting manholes on the 54-inch inlets can be utilized  as monitoring man-
holes for inflow.
                                      614-12
The Beaver Trail retention basin has a capacity of 1.292,000 ft  (cubic
feet).  Based on current design requireuents of the Oakland County ..Drain
Commission, required capacity of the retention basin is 405,628 ft .
The design area is 135 acres with a runoff "c" factor 0.42.  The time from
start of rainfall to peak storage is approximately 118 minutes for the design
storm.  The time of concentration for the drainage area is approximately 31
minutes.  The base rainfall of 0.5 inches would generate approximately 103,000
ft  of runoff to the retention basin.  This volume would cause a depth of
water at the 16 inch outlet of approximately 2.7 feet, assuming no outflow.
The contributing area of this retention basin Is entirely residential with
the exception of some open space immediately east of the retention basin.

The Sylvan Glen Sub. No. 2 retention basin is located adjacent to the northeast
corner of Long Lake Road and Berwyck.  This basin is in excellent condition,
we'll maintained with no excessive weed or cat-tail growth.  There is no outlet
structure visible which could serve as a monitoring manhole.  The Sylvan Glen
retention basin has i. capacity of 220,000 ft .  The design area is 75 acres
with a runoff "c" factor of 0.42.  The time from start of rainfall to peak
storage is approximately 100 minutes.  The time of concentration for the
drainage area is approximately 37 minutes.

The base rainfall of 0.5 inches would generate approximately 40,837 ft  of
runoff to the retention basin.  This volume would cause a depth of water of
4 feet at the 12-inch outlet, assuming no outflow.

The contributing area to this retention basin is entirely residential.

The Village Green of Troy retention basin is located southwest of the Big
Beaver Road (16 Mile Road)/I-75 Interchange.  This basin is in generally ex-
cellent condition with short grasses over a majority of the site.  Some erosion
and standing water is present near the inlet.  Manholes exist on the inlet off-
site and on the outlet on-slte.  These existing structures show promise for
use as sampling stations.

The Village Green of Troy retention basin has a capacity of 1,466,000 ft .
Based on current design requirements of the Oakland County Drain Commission,
required capacity of the retention basin Is 776,480 ft .  The design area is
60 acres with a runoff "c" factor of 0.6.  The time from start of rainfall to
peak storage is 148 minutes for a design storm.  The time of concentration of
the drainage area Is approximately 26 minutes.

The base rainfall of 0.5 inches would generate approximately 65,300 ft, of
runoff to the retention basin.  This would cause a depth of water at the
10-inch outlet of approximately 4 feet, assuming no outflow.

The contributing area to this retention basin is multiple dwellings and
commercial  use.   The high ratio of land used for parking and building increases
the imperviousness of the area, resulting in runoff factors higher than those
for the residential  areas.
                                                                                                                                        G14-13

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Stonnwater runoff from the three basin catchments for 17 events planned to be
collected at the inlet and outlet of each of  the three Stonnwater retention
basins Mill be analyzed and evaluated.

The three basins described have  been selected for study.  Two have one Inlet
and one outlet, and one has two  Inlets and one outlet for a total of seven
stations.  The flow recording Instrument  is a continuous flow recorder.  One
will be installed at each Inlet  and outlet.   This instrument is required in
order to overcome the prevailing site conditions which would cause errors in
flow measurement if other methods were employed.  The units will provide
accurate flow measurements even  though surcharge conditions do or can exist
at each station; low flows will  lead to open  channel flow, and peak flows
will result in fullpipe flows.   Influent  and  effluent hydrographs will be
produced for each event.

Automatic water sampling equipment will be coupled to and be paced by the
flow recorders.  Regardless of the flow regime at any point in the storm event,
this combination of equipment will produce a  representative flow weighted com-
posite sample for analysis at the basin inlets and outlets.

At least two members of the sampling team will be on call during periods when
the designated wuather service  Indicates  a reasonable probability of an ap-
propriate stonn event occurring.  The data gathering team will mobilize to
the retention basins immediately upon the onset of the precipitation event.
Precipitation and flow measurements will  then be performed on a time related
basis to enable correlation with rain gauge data from the SEMCOG network and
gauges added at the retention basin site.

Loadings at each influent and effluent for each event will be determined/
estimated for each parameter in  the following list:

                    Biochemical  Oxygen Demand (ODD)
                    Total Organic Carbon  (TOC)
                    Chemical Oxygen Demand (COD)
                    Total Phosphorus
                    Orthophosphate
                    Total Kjeldahl Nitrogen (TKN)
                    Ammonia Nitrogen
                    Nitrate and  Nitrite Nitrogen
                    Metal Ions  (Pb, Fe, Zn, Cr, Cd. Cu, Ni. As, Hg)
                    Pesticides  (8. chlorinated)
                    Total Suspended Solids (TSS)
                    Total Dissolved Solids (TOS)
                    Particle Size Analysis (lu, 4u, lOu, 62.5u, 125u)
                    Fecal Coliform
                    ph
                    Chloride

Precipitation data is also needed with respect to events.  Quantity - A rain
event history including the rain duration. Intensity and quantity will be
determined for each event and basin which is  monitored.  The primary source
of rainfall quantity information will be  the  recording rain gauge located near
the junction of Long Lake River  and Rochester Roads in Troy.  This gauge
                                       G11-14
1s within approximately two miles of the retention basins which have  been
selected for study and is part of SEMCOG's raingauge  network.  Hyetographs
will be constructed from this data to assist  in characterization  of the storm
event.  In addition, manually read rain gauges will be  placed  adjacent  to
each test basin to verify the uniformity of precipitation or to allow for
adjustments in the rainfall volumes for a given basin should the  precipi-
tation event prove to he non-uniform.

Quality - The chemical characteristics of the rainfall  will also  be sampled
as a part of this program.  It is presently projected to perform  such samp-
ling at one of the three test basins during each  stonn  event monitored.  This
task will require locating a relatively large rainfall  collector  pan  in the
immediate vincinity of one of the test basins.  This  approach  will provide
Information not only as to the potential for  pollutants to  be  contributed by
atmospheric washout In general, but also to the determination  of  whether
any localized situation alters the rainfall chenical  characteristics  between
the basins being studied.

At least Initially, the parameters to be evaluated on the collected precipitation
samples will Include the majority of those to be  investigated  with respect
to the retention basins.

                        Precipitation Parameters

          Biochemical Oxygen Demand (BOD)
          Total Organic Carbon (TOC)
          Total Phosphorus
          Total Kjeldahl Nitrogen
          Ammonia Nitrogen
          Nitrate plus Nitrite Nitrogen
          Metal Ions (Pb, Fe, Zn, Cr. Cd, Cu, Nl, As, Hg)
          pH
          Chloride

D.   Controls

As previously described, this project is evaluating existing Stonnwater
detention basins installed for quantity control,  and  modified  for quality
control, for effectiveness and costs.
                                                                                                                                     G14-15

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     NATIONWIDE URBAN RUNOFF PROGRAM
SOUTHEAST MICHIGAN COUNCIL OF GOVERNMENTS
           ANN ARBOR - MICHIGAN
            DETROIT, MICHIGAN
      U.S. ENVIRONMENTAL PROTECTION

                 REGION V
                       G15-1

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                              INTRODUCTION
The City of Ann Arbor, situated in Uashtenaw County is  located  in  southeastern
Michigan, approximately 60 miles west of Detroit.   Ann  Arbor's  surface topo-
graphy was determined largely by glacial processes.   Rolling  hills predominate
with some interspersed flat areas, pothole lakes,  and wetlands.  Occasional
steep slopes will be found.  The area Includes an  extensive system of  storm-
drains consisting of both open and enclosed channels.  Main lines  tend to
follow the course of former natural streams, and outlet to the  Huron River
which passes through Ann Arbor in a series of run-of-the-rlver  impoundments.
The Huron river flows directly Into the western basin of Lake Erie.

The impoundment above Geddes Dam in Ann Arbor, which reaches  about one-half
the distance upstream to Argo Dam, is identified as Geddes Pond.   This water
body is identified In the Michigan State Water Quality  Standards as protected
for partial body contact recreational use with a goal for total body contact
recreational use in the future.  The free-flowing  stretch of  the Huron River
would come under the general classification of being protected  for agricultural
uses, navigation, Industrial water supply, public  water supply  at  the  point
of water intake, warmwater fish, and partial body  contact recreation.   There
have been water quality standards violations.

Hater  quality surveys conducted in the 1970's generally disclosed  water
quality conditions during dry weather flow to be reasonably good,  while
pollutant levels increased dramatically during stormwater runoff periods.
The population in the area has shown considerable  growth, increasing from
about 67,000 in 1960 to about 107,000 in 1980, a rate of 60X in 20 years.  The
rate has slowed down during ten years from 1970 to 1980, with a gain of only
about 7.5X.  This still Mould result In a projection of further growth during
the next twenty years.  Population may easily reach 115,000 with continued
urbanization, since the growth rate In the urbanized area was 16.7% between
1970 and 1980.

The Southeast Michigan Council of Governments, In  the development  of the
Section 208 Managenent Plan, identified the reach  of the Huron  River between
the Argo and Geddes Dams as one of three problen areas.  With no point source
discharges, the focus Is on nonpoint sources  in this stretch of the river.
The SEMCOG Section 208 program Included an overall approach for managing
pollution from urban nonpoint sources of pollution.  The area in which this
project is located had the highest priority of the three identified problem
areas.
LAKE
MICHIGAN
LAKE
HURON
                                                :AHH ARBOR
                                                      LAKE
                                                      ERIE
                                                                                                                                     FIGURE 1
                                    G15-2
                                                                                                                                     G15-3

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          USGS QUAD SHEET


             FIGURE 2A
              G1S-4
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                                                                                       G15-5

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                          PHYSICAL  DESCRIPTION
A.   Area

The City of Ann Arbor,  situated  in Washtenaw County,  is  located  in southeastern
Michigan, approximately 60 miles west  of  Uetroit.  The total area of the city
comprises 26.5 square miles,   land use within the town Is characterized as
institutional and residential, with associated commercial development, and
some industrial use.

B.   Population

Ann Arbor is the home of the  University of Michigan,  with parts  of the campus
on either side of the Huron Kiver.  The census population figure for the City
of Ann Arbor for 1970 was 99,797, representing a 48.2 precent  increase from
the 1960 census population.  The 1980  Census population  figure was reported
as 107,316, a much lower 1% Increase.   The Washtenaw  County standard metro-
politan statistical  area population was reported as increasing by 35.8% from
1960 to 1970, when it was 234,103.  By 1980. It had become 264,103, a 14
percent increase.  City population is  projected to continue to grow, although
not as rapidly as in the last twenty years,  and Is projected to  increase to
about 115,00 by the year 2000.

C.   Drainage

Ann Arbor's topography  is predominately rolling hills, with some flat areas,
potholes and wetlands.   The Huron River flows through the city from the north-
west to the southeast,  through both free  flowing and  impounded reaches.  The
drainage in sub-watersheds is divided  Into  five specific drainage districts
(Figures 3-6), identified as  follows:

     a.   Traver Creek  Drainage  District, rural and with a relatively flat
          grade away from the urbanizing  area, it becomes steeper and with
          more development downstream. Much flood damage has  been exper-
          ienced in this area due to the  nature of the watershed shape,
          streambed slope and development.

     b.   Swift Run Drainage  District, also  agricultural in the  upper portion,
          includes a wetland  preserved by the Drain Commission to provide
          storage and water quality improvements.  Below the wetland, to the
          Huron River,  there  has been  a high level of urbanization, reducing
          pervious areas and   increasing runoff rates  through stormdrains.

     c.   Allen Creek Drain Drainage District is  located in the  urban areas
          of Ann Arbor  and is extensively served with an enclosed storm drainage
          network.  The configuration  and intense development  result  in a
          very short time requiranent  to  concentrate  peak flows.

     d.   North Campus  Drain  Drainage  District is  located adjacent  to the
          Traver Creek  Drain  onthe north  side of  the  Huron River.   There  is
          less development along this  open  natural watercourse,  which outlets
           into the Geddes Pond  impoundment  of the Huron  River.
                                   G15-6
     e.   The  Pittsfleld-Ann Arbor Drain Drainage District comprised  the  sub-
          watershed  lying  between the Allen Creek and Swift Run Drain Drainage
          Districts.  Tills drain has been modified by straightening, deeping,
          widening and enclosing some portions.  In addition, on-line retention
          basins  have  been constructed.   The Pittsfleld-Ann Arbor Drain Drainage
          District can be  divided into 3 sub-districts.  The South arm district
          comprises  approximately 31< of the total area and has the least
          impervious area.  The North arm district includes part of the
          University with  attendant high density residences and some com-
          mercial development.   The remaining sub-district is highly urban-
          ized  and contains the most Impervious surface area.

D.   Sewerage System

The sanitary wastes  are carried through  a separate collection system to
treatment facilities,  with the  treated effluent discharged to the Huron River
below Geddes Dara.  Although a separate sanitary sewer system was developed,
In the Allen Creek Drain prior  studies suggest that CrossConnect ions exist
within certain  sub-districts.
                                                                                                                                    G15-7

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                                                                                                                           PROJECT AREA
The following station codes and descriptors identify the  locations of  the
monitoring stations:
     Descriptor

     Pittsfield-ARii Arbor Drain
          South Inlet
          North Inlet
          Basin Outlet
          Outlet to River

     Swift Run Drain
          Inlet
          Outlet
          Outlet to River

     Traver Creek Drain
          Outlet to River
          Basin Inlet
          Basin Outlet

     North Campus Drain
          Outlet to River

     Allen Drain
          Outlet to River
                                                  Station Code
PITAARETBNSINLT
PITAARETBNNINLT
PITAA RET BN OT
PITTS-AA UR OT
SR WETLANDS INT
SR WETLANDS OT
SWIFT RUN OR OT
TRAV CK OR OT
TRAV CK RT BN I
TRAV CK RT BN 0
N CAMPUS Oft OT


ALLEN OR OUTLET
1.    Catchment Name - HI3,  PITAARETBNSIHLT

     A.    Area - 2001 acres.

     B.    Population - 3800 persons.

     C.    Drainage - This catchment  area has a representative slope of 33.8
          feet/mile, 30% served  with  curbs and gutters and 70% served with
          swales and ditches.  The storm sewers approximate a 17.6 feet/
          mile slope and extend  10,000 feet.

     D.    Sewerage - Drainage  area of the catchment is 100* separate storm
          sewers.

          Streets consist of 35  lane  miles of asphalt. 54% of which is in
          good condition and 46% of  which is in fair condition.   In addition
          there are about 15 lane miles of concrete, all  of which is in good
          condition, and 1  lane  miles of other materials, all of which is in
          good condition.

     E.    Land Use

          345 acres (17.2%) Is < 0.5  dwelling units per acre urban residential,
          of which 4 acres  (1.2%) is  impervious.

          117 acres (5.8%)  is  0.5 to  2 dwelling units per acre urban residential,
          of which 5 acres  (4.3%) Is  impervious.

          62 acres (3.IX) is 2.5 to 8 dwelling units per  acre urban residential,
          of which 30 acres (48.4%)  is impervious.

          92 acres (4.62) is > 8 dwelling units per acre  urban residential,
          of which 64 acres (69.6%)  is impervious.

          457 acres (22.8%) is Commercial, of which
          264 acres (57.8%) is Impervious.

          138 acres (6.9%)  is  Industrial, of which
          12 acres (8.7%) is Impervious.

          485 acres (24.2%) is Parkland,  of which
          42 acres (8.7%) is Impervious.

          305 acres (15.2%) is Agriculture,
          of which 4 acres  (1.3%) is  Impervious.

II.   Catchment Name - NI3.  PITAARETBNNINLT

     A.    Area - 2871 acres.

     B.    Population -  18,800  persons.
                                    G15-8
                                                                                                                                 G15-«

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     C.   Drainage - This catchment  area  has  a representative slope of 60.7
          feet/mile, 68X served with curbs  and gutters and 32% served with
          swales and ditches.   The storm  sewers approximate a 10.6 feet/
          mile slope and extend 10,200 feet.

     D.   Sewerage - Drainage  area of the catchment Is 100* separate storm
          sewers.

          Streets  consist of 89 lane miles  of asphalt. 58X of which Is In
          good condition, 40X  of which Is In  fair condition, and 2X of which
          Is in poor condition.   In  addition  there are about 9 lane miles of
          concrete,  all  In good condition,  and 4 lane miles of other materials,
          all of which Is In good condition.

     E.   Land Use

          11 acres (0.4X) Is <  0.5 dwelling units per acre urban residential,
          of which 1 acre (9.IX)  Is  Impervious.

          211 acres  {8.IX)  Is  0.5 to 2 dwelling units per acre urban residential.
          of which 17 acres (7%)  Is  Impervious.

          938 acres  (32.7X) Is  2.5 to  8 dwelling units per acre urban residential,
          of which 293 acres (31.2X)  Is Impervious.

          378 acres  (13.2X) Is  >  8 dwelling units per acre urban residential,
          of which 220 acres (58.2X)  is Impervious.

          293 acres  (10.2X) is  Commercial, of which
          150 acres  (51.2X) Is  Impervious.

          80 acres (2.8X) Is Industrial, of which
          40 acres (50*)  Is Impervious.

          618 acres  (21.5X) is  Parkland, of which
          26 acres (4.2%) Is impervious.

          312 acres  (10.9X) Is Agriculture,  of which
          6  acres  (1.9X)  is impervious.

III.  Catchment  Name  -  HI3,  PITAA  RET BH OT

     A.   Area  - 4872  acres.

     B.   Population - 22,600 persons.

     C.   Drainage - This catchment  area has a representative slope of 45.5
          feet/mile,  52X  served with curbs and gutters and 48X served  with
          swales and ditches.  The storm sewers approximate a 14.1  feet/mile
          slope and  extend 20,000 feet.
                                  G15-10
IV.
D.   Sewerage - Drainage area of the catchment is 100X separate storm
     sewers.

     Streets consist of 124 lane miles of asphalt, 57X of which is in
     good condition, 41X of which is In fair condition, and 2X of which
     Is in poor condition.  In addition there are about 6 lane miles of
     concrete, all In good condition, and 6 lane miles of other materials,
     all of which is good condition.

E.   Land Use

     356 acres (7.3X) is < 0.5 dwelling units per acre urban residential,
     of which 5 acres (1.4*) is  impervious.

     358 acres (7.4X) is 2.5 to 8 dwelling units per acre urban residential,
     of which 22 acres (6.2X) Is impervious.

     1000 acres (20.5X) Is 2.5 to 8 dwelling units per acre urban residential,
     of which 323 acres (32.3X)  Is  Impervious.

     470 acres (9.6X) is > 8 dwelling units per acre urban residential,
     of which 284 acres (60.4X)  is  impervious.

     750 acres (15.4X) Is Commercial, of which
     414 acres (55.2X) Is Impervious.

     218 acres (4.5X) Is  Industrial, of which
     52 acres (23.8X) is  Impervious.

     1103 acres (22.6X) Is Parkland, of which
     68 acres (6.2X)  is impervious.

     617 acres (12.7X) Is Agriculture, of which
     10 acres (1.6X)  is Impervious.

Catchment Name - MI3, P1TTS-AA  OR OT

A.   Area -  6,363 acres.

8.   Population - 27,700  persons.

C.  . Drainage  - This  catchment  area has  a representative  slope of  61.6
     feet/mile,  7SX served with curbs  and gutters and  25X served with
     swales and ditches.   The  storm sewers  approximate a  15.4  feet/mile
     slope  and extend 33,900 feet.

D.   Sewerage  - Drainage  area of the catchment  Is 100X separate storm
     sewers.

     Streets consist  of 209 lane miles of  asphalt,  49X is in good  condition,
     SOX of which is  in  fair condition,  and IX  of which Is in  poor condition.
      In  addition,  there  are about  26 lane miles of concrete,  all  in good
     condition,  and 0 lane miles of other materials,  all  In good  condition.
                                                                                                                                       G15-11

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     E.   Land Use

          356 acres (5.6*) Is < 0.5 dwellimj  units  per  acre  urban residential.
          of which 5 acres (1.4%)  is impervious.

          483 acres (1.6%) is 0.5  to 2  dwellimj  units per  acre  urban residential,
          of which 29 acres (6S)  is impervious.

          1714 acres (26.9%) is 2.5 to  8  dwelling units per  acre urban residential,
          of which 462 acres (27%)  is impervious.

          510 acres (8%) is > 8 dwellimj  units per  acre urban residential,
          of which 314 acres (61.6%) is impervious.

          861 acres (13.5%) is Commercial, of which
          499 acres (58%)  is impervious.

          218 acres (3.4%) Is Industrial, of  which
          52 acres (23.8%) is impervious.

          1604 acres (25.2%) is Parkland, of  which
          88 acres (5.5%)  is impervious.

          617 acres (9.7%) Is Ayr(culture, of which
          10 acres (1.6%)  is impervious.

V.   Catchment Name - HI3, SR WETLANDS  INT

     A.   Area - 1207 acres.

     B.   Population - 2700 persons.

     C.   Drainage - This  catchment area  has  a representative slope of 32.1
          feet/mile, 13% served with curbs and gutters  and 87%  served with
          swales and ditches.  The  storm  sewers  approximate  a 6.9 feet/mile
          slope and extend 8.000 feet.

     0.   Sewerage - Drainage area  of the catchment  Is  100%  separate
          storm sewers.

          Streets consist  of 5 lane miles of  asphalt, 20% of which is In good
          condition and  80% of which is In fair  condition.   In  addition there
          area about 3 lane miles of concrete, all  In good condition, and 5 lane
          miles of other materials, all in good condition.

     E.   Land Use

          509 acres (42.2%) is < 0.5 dwelling units  per acre urban residential,
          of which 5 acres (1%)  is  impervious.

          30 acres (2.5%)  is 0.5 to 2 dwelling units per acre urban residential,
          of which 3 acres (10%) is impervious.
          13 acres (1.1%)  is  2.5 to B dwelling units per acre urban residential,
          of which 3 acres (23.1%)  is impervious.

          90 acres (7.5%)  is  > 8 dwelling units per acre urban residential,
          of which 23 acres (25.6%) is impervious.

          4 ac,-cs (0.3%)  is Cowaercia!,  of which
          1 acre (25%) is  impervious.

          14 acres (1.2%)  is  Industrial, of which
          3 acres (21.4%)  is  impervious.

          187 acres (15.5%) is Parkland, of which
          2 acres (1.1%)  is impervious.

          360 acres (29.8%) is Agriculture, of which
          3 acres (0.8%)  is impervious.

VI.  Catchment Name - HI3, SR WETLANDS OT

     A.    Area - 1227 acres.

     B.    Population - 2,700  persons.

     C.    Drainage - This  catchment area has a representative slope of 32.1
          feet/mile. 13%  served with curbs and gutters and 87% served with
          swales and ditches.  The  storm sewers approximate a 6.9 feet/mile
          slope and extend 8,000 feet.

     D.    Sewerage - Drainage area  of the catchment is 100% separate storm
          sewers.

          Streets consist  of  5 lane miles of asphalt, 20% of which is in
          good condition  and  80% of which is in fair condition.  In addition
          there are about  3 lane miles of concrete, all in good condition.
          and 5 lane miles of other material, all  in good condition.

     E.    Land Use

          509 acres (41.5%) is < 0.5 dwelling units per acre urban residential,
          of which 5 acres (1%) is  Impervious.

          30 acres (2.4%)  is  0.5 to 2 dwelling units per acre urban residential,
          of which 3 acres (10%) is impervious.

          13 acres (1.1%)  is  2.5 to 8 dwelling units per acre urban residential,
          of which 3 acres (23.1%)  is impervious.

          90 acres (7.3%)  is  > 8 dwelling units per acre urban residential.
          of which 23 acres (25.6%) is impervious.

          4 acres (0.3%)  is Commercial,'of which
          1 acre (25%) is  impervious.
                                  G15-12
                                                                                                                                  G15-13

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          14 acres  (1.1X)  is  Industrial, of which
          3 acres (21.430  Is  Impervious.

          187 acres (15.2X)  is  Parkland, of which
          2 acres (1.1%)  Is  Impervious.

          360 acres (29.3X)  is  Agriculture, of which
          3 acres (0.8%)  is  impervious.

          20 acres  (1.6X)  Is  Wetlands.

VII. Catchment Name -  MI3, SWIFT RUN OR OT

     A.    Area -  3075  acres.

     6.    Population - 10.800 persons.

     C.    Drainage  - This  catchment area has  a representative slope of 39.6
          feet/mile, 42< served with curbs and gutters and 58X served with
          swales  and ditches.   The storm sewers approximate 17.6 feet/mile
          slope ami extend 24,000 feet.

     0.    Sewerage  - Drainage area of the catchment is 100X separate storm
          sewers.

          Streets consist  of  63 lane miles of asphalt, 38X of which is in
          good condition and  62* of which is  In fair condition.  In addition
          there are about  15  lane miles of concrete, all of which is in good
          condition, and 9 lane miles of other material, all in good condition.

     E.    Land Use

          509 acres (16.6%)  Is  < 0.5 dwelling units per acre urban residential.
          of which  5 acres (IX) Is  impervious.

          151 acres (4.9X) is 0.5 to 2 dwelling units per acre urban residential.
          of which  10  acres  (6.6X)  is  impervious.

          574 acres (18.7X)  Is  2.5  to 8 dwelling units per acre urban residential,
          of which  103 acres  (17.9X)  Is  impervious.

          319 acres (10.4%)  is  > 8  dwelling units per acre urban residential,
          of which  140 acres  (43.9%)  Is  impervious.

          123 acres (4X) Is  Commercial, of which
          97 acres  (78.9X) is impervious.

          14 acres  (0.5%)  is  Industrial, of which
          3 acres (21.4*)  is impervious.

          1005 acres (32.7X)  is Parkland, of  which
          63 acres  (6.3X)  is impervious.

          360 acres (11.7X)  is  AgricuHure. of which
          3 acres (0.8X) Is  impervious.

          20 acres  (1.6X)  is Wetlands.
                                   G15-14
VIII.  Catchment Name - HI3, TRAV CK OR OT

     A.   Area - 4402 acres.

     B.   Population - 8400 persons.

     C.   Drainage - This catchment area has a representative slope of 68.6
          feet/mile, 18X served with curbs and gutters and 822 served with
          swales and ditches.  The storm sewers approximate a 37.8 feet/mile
          slope and extend 25.700 feet.

     D.   Sewerage - Drainage area of the catchment is 100X separate storm
          sewers.

          Streets consist of 41 lane miles of asphalt, 15X of which is in
          good condition and 85X of which is in fair condition.  In addition
          there are about 17 lane miles of concrete, of which 100% is in good
          condition, and 18 lane miles of other materials, all in good
          condition.

     E.   Land Use

          125 acres (2.6X) is < 0.5 dwelling units per acre urban residential.
          of which 6 acres (4.8X) is Impervious.

          161 acres (3.7X) Is 0.5 to 2 dwelling units per acres urban residential,
          of which 7 acres (4.4X) Is Impervious.

          174 acres (4%) is 2.5 to 8 dwelling units per acre urban residential,
          of which 32 acres (18.4%) is Impervious.

          192 acres (4.4X) is > 8 dwelling units per acre urban residential,
          of which 114 acres (59.8X) is Impervious.
          49 acres
          38 acres
(1.1%) is Commercial, of which
(77.6%) Is Impervious.
          96 acres (2.2X) Is Industrial, of which
          3 acres (3.IX) is Impervious.

          1530 acres (34.8%) is Parkland, of which
          70 acres (4.6X) is impervious.

          1862 acres (42.3X) Is AgricuHure, of which
          130 acres ( 7%) is impervious.

          213 acres (4.8X) is Forest.

IX.   Catchment Name - HI3. TRAV CK RT BN I

     A.   Area - 2303 acres.

     B.   Population - 160 persons.
                                                                                                                                 G15-15

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     C.   Drainage - This catchment  area has a representative  slope of  33.2
          feel/mile, 100< served with swales and  ditches.   The storm  sewers '
          approximate a 28.5 feel/mile slope and  extend  9.500  feet.

     0.   Sewerage - Drainage area of the catchment  is  100% separate  storm
          sewers.

          Streets  consist of 17 lane miles of asphalt,  100% of which  is  in
          good condition.  In addition there are  about  15  lane miles  of
          concrete,  of which 1002 is in good condition,  and 10 lane miles of
          other materials,  all  in good condition.

     E.   Land Use

          125 acres  (5.4*)  is < 0.5  dwelling units per  acre urban residential,
          of which 6 acres  (4.8%) is impervious.

          52 acres (2.3%) is 0.5 to  2 dwelling units  per acre  urban residential,
          of which 2 acres  (3.8%) Is impervious.

          10 acres (0.4%) is Commercial,  of which
          3 acres  (30%) is  impervious.

          37 acres (1.6%) is Industrial,  of which
          1 acre (2.7%) is  impervious.

          4 acres  (0.2%) is Parkland, of which
          1 acre (25%) Is impervious.               '

          1862 acres (80.8%) is Agriculture.
          of which 130 acres (7%) is impervious.

          213 acres  (9.2%)  is Forest.

X.   Catchment Name  - HI3,  TRAV CK RT BN OT

     A.   Area - 2327 acres.

     B.   Population * 160  persons.

     C.   Drainage - This catchment  area has a representative  slope of 33.2
          feet/mile, 100% served with swales and ditches.   The storm  sewers
          approximate a 28.5 feet/mile slope and extend  9.500  feet.

     U.   Sewerage - Drainage area of the catchment  is  100% separate  storm
          sewers.

          Streets  consist of 17 lane miles of asphalt,  100% of which  is
          in fair  condition. In addition there are about  15 lane miles of
          concrete,  of which 100% is in good condition,  and 10 lanes miles
          of other materials,  all in good condition.

     t.   Land Use

          125 acres  (5.4%)  is < 0.5  dwelling units per acre urban residential,
          of w