United States
Environmental Protection
Agency
Region V
Great Lakes National
Program Office
536 South Clark Street, Room 932
Chicago, IL 60605
EPA-905/9-81-002
Best Management
Practices
Implementation
Rochester, N ew York
-------
FOREWORD
The Environmental Protection Agency was created because of increasing
public and government concerns about the dangers of pollution to the health
and welfare of the American people. Noxious air, foul water, and spoiled
land are tragic testimony to the deterioration of our natural environment.
The complexity of that environment and the interplay between its components
require a concentrated and integrated attack on the problem.
Research and development is that necessary first step in problem
solution and it involves defining the problem, measuring its impact, and
searching for solutions. The Municipal Environmental Research Laboratory
and6™™.116" f d/mpr°Ved technol°Sies a"d systems for the prevention, treatment,
and management of wastewater and solid and hazardous waste pollutant discharges
from municipal and community sources, for the preservation and treatment of
public drinking water supplies, and to minimize the adverse economic, social
health, and aesthetic effects of pollution. This publication reflects the
application of research, in a project scale demonstration of innovative
technology.
In order to support the demonstration of new methods and techniques
for the control of pollution within the Great Lakes, Congress provided funds
through Section 108 of the Clean Water Act. This projecf to develop and
demonstrate innovative yet practical approaches to solve problems caused by
discharges from combined sewers, has been funded by Section 108 through the
Great Lakes National Program Office.
The deleterious effects of stormsewer discharges and combined sewer
overflows upon the nation's waterways have become of increasing concern in
recent times.
This report presents the overall framework for the implementation of
Best Management Practices (BMP) concepts for the management of combined sewer
overflows from the City of Rochester impacting the Genesee River. The
configured BMP program involving source and collection system management
options significantly reduces annual pollutant loadings from CSOs and is
readily compatible with capital-intensive pollution abatement options that
are needed for control of pollutants from large storms.
Francis T. Mayo, Director
Municipal Environmental
Research Laboratory
Cincinnati, Ohio
Madonna F. McGrath, Director
Great Lakes National Program
Office
Chicago, Illinois
-------
EPA-905/9-81-002
April 1981
BEST MANAGEMENT PRACTICES IMPLEMENTATION
ROCHESTER, NEW YORK
by
Cornelius B. Murphy, Jr., Ph.D.
Dwight A. MacArthur, P.E.
David J. Carleo, P.E.
O'Brien 5 Gere Engineers, Inc.
Syracuse, New York
Thomas J. Quinn, P.E.
James E. Stewart
Monroe County Division of Pure Waters
Rochester, New York
Project Officer Technical Assistance
Lawrence Mori arty ^EPA^SCSS S."
USEPA-Region II USEPA-SCSb-MtKL
Rochester, New York Edison, New Jersey
Grant Officer
Ralph G. Christensen
Section 108(a) Program Coordinator
USEPA-Region V
Chicago, Illinois
Municipal Environmental Research Laboratory
U.S. Environmental Protection Agency
Cincinnati, Ohio 45268
Great Lakes National Program Office
U.S. Environmental Protection Agency
536 South Clark Street, Room 932
Chicago, Illinois 60605
U.S. Environmental Protection Agency
Region V, Library
230 South Dearborn Street
Chicago, Illinois 60604 ..,,;
-------
DISCLAIMER
JSTCS
U,S. Environmental Protection Agencfg
-------
ABSTRACT
In light of significant capital and operating costs associated with
structurally-intensive storage/treatment pollution abatement alternatives,
the aDDlication of selected Best Management Practices (BMPs) offered an
attraave and feasible alternative to the partial solution of stormwater
runoff nduced receiving water quality impairment for the City of Rochester,
New York The configured BMP program resulted in a measurable reduction
?n the frequency and volume of combined sewer overflow (CSO) discharged to
the Genesee River. The study defined and outlined the effective BMP
measures! advanced a methodology of approach, and established preliminary
cost/benefit relationships.
A program of source control and collection system management BMP con-
cents proved effective in reducing the frequency and volume of CSO for storm
events w?th rainfall volumes of 0.25 in. or less. For intense storm events
the identified system improvements resulted in minimal CSO reductions.
Evaluations were conducted on the use of porous pavement, improved
street and catchbasin cleaning practices, installation of inlet control
devices, and the implementation of minimal structural improvements to the
existing sewer collection system. For the City of Rochester, selective use
of porous pavement and inlet control devices in conjunction with minimal
structural improvements to the main interceptor and overflow regulators,
selective trunk sewer rehabilitation, and the installation of control
structures at various locations throughout the sewer system proved to be the
Sst effective in reducing the average annual volume of CSO discharged to the
Senesee River The implemented and proposed BMP measures were compatible and
complementary with ongoing structurally-intensive abatement programs.
This report was submitted in fulfillment of Federal Great Lake Initia-
tive Grant No. G00533401 by O'Brien & Gere Engineers, Inc. under the partial
sponsorship of the U.S. Environmental Protection Agency. This report
cohered a period from October 1978 to November 1980 and was completed by
February 1981.
ill
-------
CONTENTS
PAGE
Inside cover
Fo reward
iv
Abstract
V1'i
Figures
xi
Tables
Abbreviations and Symbols
Acknowledgment
y "i "i *\
xv
1. Introduction *
Background 1
Problem Definition •*
Proposed Solution
2. Conclusions 6
3. Recommendations 10
4. Study Area Background 14
General \°*
Previous Studies JJ
Drainage Area Description 18
Sewer System Description 20
Water Quality Considerations 27
5. Overflow Monitoring 31
General 31
Rainfall Analysis j»
Overflow Monitoring »^
Overflow Quality Considerations 55
-------
PAGE
6. Source Control Management 7Q
Catchbasin/Street Sweeping Evaluations 7n
Porous Pavement Demonstration oo
Inlet Control Concepts no
Other Source .Control Measures JQJJ
7. Collection System Management 115
Minimal Structural Improvements 115
Selective Trunk Sewer Investigations 147
Structural Improvements to Maximize Use of
Existing System 157
Impact on Treatment Plant 169
8. Receiving Water Studies 184
Benthic Demand 184
Receiving Water Investigations 196
9. BMP Program Implementability 215
Combinations of BMP Options 215
Anticipated CSO Reductions 215
Costs and Financing 217
Schedule of Implementation 218
Legal and Institutional Constraints 221
Relationship to Other Ongoing Pollution Abatement
Programs 222
References 223
VI
-------
Number
FIGURES
Page
1 Combined sewer overflow locations within the City of
Rochester .
2 Elements of a typical BMP program *
3 Study area location map ._
4 Drainage areas within the City of Rochester i»
5 Major subbasins tributary to Genesee River within
City of Rochester
6 Network of major trunk sewers and interceptor for
City of Rochester /CDDT-* 9c
7 Location map for St. Paul Boulevard Interceptor (SPBI) &
8 Schematic of the SPBI and trunk sewer system g
9 Grit chamber locations ._
10 CSO monitored sites within the City of Rochester ^
11 Head measurement for open-channel monitoring location M
12 Head measurement for weir monitoring location «
13 Schematic of overflow monitoring and telemetry systems ^
14 Example curve - storm magnitude vs. frequency JJ
15 Example curve - storm intensity vs. frequency Ji
16 Example curve - storm duration vs. frequency ^
17 Example curve - percent of storms having maximum
hourly intensity vs. hour after start of storm ^
18 Rainfall frequency - intensity - duration curves for
Rochester, New York 7~
19 Rain gauge location map .
T •_! ts „ .p^v. 01 May RH c-t-nvm t:?
Iso-pluvial lines for 21 Mar 80 storm
*_ . _ _ . f* r* r\ T..T D f\ *• ± f*. u*m J3 U
51
23 Airport"rain'data vs". local rain gauge data^for site 36 54
— a -.
21 Iso-pluvial lines for 22 Jul 80 storm
22 Iso-pluvial lines for 26 Jun 80 storm Di
tAIIJJUIUlw-in^****"*'*-- • ^ ^ - ,
24 Rainfall-overflow regression equations by site _
25 General location map for catchbasin/street sweeping
demonstration study
26 Schematic of catchbasin/street sweeping demonstration
site representing a residential area _ /b
O 1 UC IC|JIC*>«-iiwiiiy w» ,»„«.— — ..-. — • — - _ ^
27 Schematic of catchbasin/street sweeping demonstration
site representing a commercial area ''
28 Residential test area
KGb lUtMIL 10 I ocoo ui tv* __
29 Commercial test area
30 General location map for porous pavement
demonstration sites ,
31 Schematic of porous pavement demonstration site
at the GCO treatment plant °°
32 GCO porous pavement demonstration site ay
vii
-------
Number
33 general layout of Lake Avenue porous pavement site 89
34 Runoff hydrographs for 28 Apr 80 storm event g?
35 Porous pavement permeability testing with sand addition 96
36 Schematic of a Hydro-Brake regulator 99
37 Schematic of Santee Area Hydro-Brake demonstration site 101
38 Homeowner's survey questionnaire 102
39 Schematic of off-line storage facilities associated
An D1 W1? Sa2*ee Area Hydl"0-Brake demonstration site 104
40 Plan and profile of off-line storage tank for the
Santee Hydro-Brake demonstration inc
41 Flow monitoring locations within Santee Area Hydro-
Brake demonstration site 107
42 Combined sewage flow depths at Emerson & Robin for
selected storms log
43 Combined sewage flow depths on Michigan Street for
selected storms 11Q
44 Location of flow restrictive sections of the SPBI 118
45 Hydraulic capacity profile of the St. Paul
Boulevard Interceptor i20
46 Schematic of existing sewer system for City of
Rochester SSM analysis 12c
47 Projected annual overflow volume under various
BMP improvement concepts 127
48 Schematic of typical float-operated regulator 130
49 In-system storage volume estimations using the
level pool method 137
50 Example of effectiveness of increasing overflow
weir heights 139
51 Hydro-Brake unit before installation 141
52 Head-discharge curve for the Hydro-Brake
regulator at Lexington Avenue 142
53 Photograph of installed Hydro-Brake regulator looking
at the inlet 143
54 Overflow volume vs. storage/treatment relationship
for the Hydro-Brake regulator at Lexington
Avenue 145
55 Overflow duration vs. storage/treatment for the
Hydro-Brake regulator at Lexington Avenue 145
bb Relationship between upstream and downstream depths
at the Lexington Avenue Hydro-Brake regulator
for the 1 Nov 80 storm 148
57 Relationship between upstream and downstream depths
at the Lexington Avenue regulator for the
22 Oct 80 storm 149
58 Location map for the West Side Trunk Sewer 151
59 Location map for the East Side Trunk Sewer 153
60 East Side Trunk Sewer inspection results 155
61 Overflow volume vs. storage/treatment relationships
for the East Side Trunk Sewer based on simplified
modeling
viii
-------
Number
62 Proposed control structure locations in ' ,„
63 Computer facility associated with the BMP program 163
64 in-system monitoring locations
65 Model projected VanLare plant effluent quality for
varying hydraulic loadings under split-flow
mode of operation
66 Split-flow TSS performance data under dry-weather
flow conditions
67 Split-flow BOD performance data under dry-weather
flow conditions
68 VanLare process performance data •„,•,-,„
69 BOD and TIP effluent concentrations under chemically
assisted split-flow mode of operation
70 TSS effluent concentrations under chemically
assisted split-flow mode of operation
71 Historical dependence of VanLare plant effluent
quality on hydraulic loading t |°;
72 Split-flow valving and instrumentation requirements i«£
73 Sediment trap locations ,R8
74 Sediment trap prior to installation J°
75 Removal and inspection of sediment trap J
76 River profiles of heavy meta] sediment concentrations i^
77 Sediment lead concentrations vs. precipitation iȣ
78 Sedimentation rate data for sediment monitoring sites 195
79 Water quality monitor location
80 Monroe County Health Department river sampling ^
location ...
81 Fecal coliform concentrations in the Genesee River
as measured by Monroe County Health Department 202
82 Rainfall hyetograph of prototype storm event
83 Model calculation of Genesee River fecal coliform
in response to CSO loads under average annual
flow conditions
84 Model calculation of Genesee River fecal coll form
in response to CSO loads under Q7_i0 flow
85 Model°calculation of Genesee River dissolved oxygen
in response to CSO loads at average yearly
flow conditions
86 Model calculation of Genesee River dissolved oxygen
in response to CSO loads at Q7_1Q flow conditions 208
87 Location of CSO discharges and recreation facilities
within the impacted area of the Genesee River
and the Rochester Embayment of Lake Ontario ^uy
88 Critical dissolved oxygen concentrations vs.
magnitude of CSO loadings
mayn i uuuc ui ^~>v ,««**, n3~ .
89 Projected maximum fecal coliform concentrations in the
Genesee River under application of vanous^control
system options to the prototype -"'" *
conditions of average river flow
IX
-------
Number
90
Projected minimum dissolved oxygen concentration in the
Genesee River under application of various system
control options to the prototype storm event for
conditions of average river flow 213
91 Schedule of implementation of BMP measures 220
-------
Number
TABLES
Page
Summary of Land Use for City of Rochester
14
2 Rochester Drainage Areas 22
\ Summary of Land Use Characteristics "
4 Summary of Drainage Area Characteristics 22
5 Water Quality Objectives Jj
6 Overflow Monitoring Installations *
7 Characteristic Flow Equations ™
Q Overflow Analysis Schedule
9 Average Monthly Rainfall in the Rochester Area - ^
10 AveragfMonfhIy Number of Raindays in the Rochester ^
11 Average'Moninly Raider Storm in the Rochester '
Area - 1954 to 1975 in7Q AA
12 Monthly Precipitation Data in Rochester Area - 1979 44
1? Kth v Precipitation Data in Rochester Area - 1980 44
4 ComparisoneCofPAnnual Average Rainfall Data Versus
1980 Rainfall Data 46
-
17 Summary of Rainfall and Combined Sewer Overflow
18 Summa^^Rain^fand Combined Sewer Overflow Volumes |6
iq First-Flush8Concentrations by Overflow Site 60
20 Comparison of 1975 Overflow Quality Data with 1979- ^
em/w^Sean Pollutant Concentrations for 1975
23 Regression hquations .y Overflow Site Correlating gy
Overflow Volumes to Total Raintans^
24 Ranking of High-Impacting Overflow Based on 6g
Pollutant Loadings 71
9* Observed Runoff Water Quality Concentrations...-
26 Summary of Sewer Flushing and Maintenance ?3
Effectiveness
XI
-------
Page
27 Costs Associated with Sewer Flushing/Maintenance
Program 74
28 Evaluation Plan for Catchbasin Studies 79
29 Summary of Catchbasin Monitoring Program Data by
Storm Event 80
30 San Jose Annual Street Cleaning Effort (1976-1977) 83
31 1979 Porous Pavement Data Base 92
32 1980 Porous Pavement Data Base 93
33 Santee Homeowner Survey Results 103
34 Monitored Storm Event Rainfall Parameters 105
35 Comparison of Design to Field Measurements Along the
Main Interceptor 122
36 Selective Interceptor Improvements 124
37 SSM Overflow Volume and Frequency Projections 126
38 Operating Characteristics of Existing Regulators 132
39 Operating Characteristics for Overflow Sites Without
Regulators 133
40 Summary of Implemented Regulator Modifications 133
41 Summary of Weir Modifications 135
42 In-System Storage Volumes Realized by Overflow Weir
Height Increases 135
43 Reduction in Overflow Volume and Duration for Various
Storage/Treatment Combinations at the Lexington
Avenue Regulator 144
44 West Side Trunk Sewer Problem Areas 152
45 East Side Trunk Sewer Storage and Conveyance Considera-
tions Developed as Result of Tunnel Inspections 154
46 Reduction in Overflow Volume and Duration for Various
Storage/Treatment Combinations at the East Side
Trunk Sewer Overflow Regulator 157
47 Realized In-System Storage Volumes by the Installation
of Control Structures 161
48 Control Structure Effectiveness in CSO Reduction 162
49 In-System Monitoring Locations 165
50 Control System Monitored Data 166
51 Process Models and Modeling Assumptions 171
52 Preliminary Testing Program Split-Flow Mode of
Operation 172
53 Evaluation Program Split-Flow Mode of Operation 172
54 Split-Flow Analysis Operating Performance Data
2/11/79 - 6/03/79 180
55 Benthic Demand Studies Evaluation Plan 137
56 Sediment Trap Data Analysis 190
57 Oxygen Uptake of Bottom Sediments in the Laboratory 193
58 Beach Closing Days 203
59 Treatment Plant and Combined Sewer Discharges and Upstream
Conditions as Defined for the Prototype Wet-Weather
Event 206
60 Program Element Costs 217
61 BMP System Improvement Costs 217
-------
LIST OF ABBREVIATIONS AND SYMBOLS
ABBREVIATIONS
AC, ac
ADT
BMP(s)
BOD
CB
cfs
CIT
CSO(s)
cy
DO
ESTS
FC
ft
ft/day
ft/sec
GCO STP
GVISW
in.2
in.o
in.
Ib
LF
MA
MA7CD/10, Q7-10
MG
MGD, mgd
MGH
ml
mg/1
mmhos/cm
mil $
mi2
mi
min
Pb
Q
R
acre
average daily traffic
Best Management Practice(s) 0
biochemical oxygen demand, 5-day at ^J t
catchbasin
cubic feet per second
Cross-Irondequoit Tunnel
combined sewer overflow(s)
cubic yard
dissolved oxygen
East Side Trunk Sewer
fecal coliform bacteria
feet
feet per day
feet per second
Gates-Chili-Ogden Sewage Treatment Plant
Genesee Valley Interceptor Southwest
inches
square inches
cubic inches
pound
linear feet
minimuTaverage 7 consecutive day flow with
10 year return period
million gallons
million gallons per day
million gallons per hour
milliliter
milligrams per liter
micro mhos per centimeter
millions of dollars
miles
square miles
minute
lead
discharge rate
removal
correlation coefficient
xm
-------
— Standard Metropolitan Statistical Area
" sediment oxygen demand
— St. Paul Boulevard Interceptor
— Simplified Stormwater Model
-- sewage treatment plant
" USEPA Stormwater Management Model
— total inorganic phosphorus
— total Kjedahl nitrogen
TSS — total suspended solids
V — volt
WB -- Weather Bureau
wk — week
WSJS — west Side Trunk Sewer
yd -- square yards
yr -- year
SYMBOLS
A»a -- cross-sectional areas
|)o» hl — original, final hydraulic head
K -- permeability coefficient
L -- length
t — time
ln -- natural logarithm
xiv
-------
ACKNOWLEDGMENT
Waters:
Dr. Gerald McDonald, Director
Mr. Oohn Davis, Deputy Director QV,a+,nnQ
Mr Thomas Quinn, Chief of Technical Operations
Mr Oames Stewart, Assistant Engineer
Mr Oohn Graham, Assistant Engineer
their guidance, suggestions and assistance.
ment of Agriculture for his advice and technical assistance in con
porous pavement studies.
The dedicated effort by the field personnel associated with Messrs.
appreciated.
& Gere Engineers, Inc., Syracuse,
ius B. Murphy, Jr., Vice President
and Mr. Dwight A. MacArthur, Managing Engineer.
xv
-------
-------
SECTION 1
INTRODUCTION
BACKGROUND
The Citv of Rochester, New York, like many of the older cities through-
nut the Un ted States and especially those in the Northeast, is served by a
"' ss.'ssvj s-
Cl I l»C 1 J Ul l\i \*wiii** iit*-'*- — — •- — -*/
sanitary and industrial wastes.
combined sewer systems were designed to adequately convey
d industrial wastes plus approximately two to three times an
tormwater. To prevent the adverse effects of excessively
hvdraulic relief was provided by overflow regulating
ctufes installed at various locations within the conveyance system. It
^
rl£3^
develop methods and processes to reduce and treat these discharges.
PROBLEM DEFINITION
the City of Rochester there are thirteen^13) maJ°^^0 points
standards for the Genesee River, impose heavy nutrient and chemical loadings
Sc Sffij-b^SToS s; ss.sn.'^s.ssrs H >e
Genesee River These CSO's also contribute excessive organic solids to the
benthos of the lower reaches of the river (2).
Both receiving water bodies, the Genesee River and Irondequoit Bay, have
very little Sslillatlon capacity for wet-weather induced CSO's. A monthly
-------
ROCHESTER EMBAYMENT
OF
LAKE ONTARIO
A CSO Discharge
City Boundary
Figure 1. Combined sewer overflow locations within the city of Rochester.
-------
cant overall improvement in water quality.
PROPOSED SOLUTION
sment technology, to date, has focused on the imp!e-
-intensive storage/treatment alternatives. The
these capital-intensive programs are enormous.
e construction of large facilities requiring long-
HIC^C |JI \jy i wii'-J i 11 * v • • •— -.. i- *•*
term design and construction periods.
solutions.
BMP program focuses on the sources of pollutants and
-ance Integral to a total BMP program is the applica-
tion of both source anS collection system management options A breakdown of
the various elements of a BMP program is shown in Figure 2 (3).
Collection system management involves the application of abatement al-
ternatives whlSh pertain to the effective management and control of the col-
lection svstem Collection system BMP abatement alternatives are those
which areyapp^ed after runoff enters the collection system. Typical solu-
-------
COMBINED SEWER OVERFLOW AND STORMWATER
BEST MANAGEMENT PRACTICES (BMP)
SOURCE MANAGEMENT
BEFORE RUNOFF ENTERS
SEWER SYSTEM
SURFACE FLOW ATTENUATION
USE OF POROUS PAVEMENT
EROSION CONTROL
:HEMICAL USE RESTRICTIONS
IMPROVED SANITATION PRACTICES
COLLECTION SYSTEM
MANAGEMENT
I
AFTER RUNOFF ENTERS
SEWER SYSTEM
INFLOW/INFILTRATION CONTROL
IMPROVED REGULATION
OPTIMIZED SYSTEM CONTROL
POLYMER ADDITION FOR FRIC-
TION REDUCTION
MINIMAL IMPROVEMENTS TO
MAKE SYSTEM SELF-
CONSISTENT
Figure 2. Elements of a typical BMP program.
-------
SSSSBS3L
tion of conveyance systems throttling constraints).
It is important to note that the effectiveness of implemented BMP
over a long period of time.
readily addressed by BMP oriented solutions.
to CSO pollution abatement.
-------
SECTION 2
CONCLUSIONS
Based on the results of this investigation, the following conclusions
relative to Best Management Practices for combined sewer overflow pollution
control are presented:
General
5.
BMPs have been shown to be effective in reducing CSO generated
during frequent, low intensity storms; however, more conventional
capital-intensive measures may be required to abate CSO pollution
tor the less frequent, high-intensity storms.
BMP collection system concepts are more easily implemented than con-
ventional solutions and tend to maximize the use of the existina
conveyance system. y
Institutional constraints, public acceptability, and the lack of
consistent performance make source control concepts less practica-
ble than collection system options as solutions to CSO problems
However, application of selected source control concepts may be
used as supplemental measures for stormwater management.
During the course of this study, it was found that the following
collection system and source control concepts were most effective
in reducing the frequency and volume of CSO discharged:
Improved system regulation
Elimination of conveyance system bottlenecks
Split-flow mode of operation at existing treatment facilities
under wet-weather conditions
Effective utilization of existing in-system storage
Porous pavement in parking lot applications, given suitable
soil conditions
Stormwater inlet control
Implementation of BMP concepts in Rochester, NY has resulted in the
following water quality and environmental benefits:
Reduction of raw wastewater discharges to the area's receiving
waters
-------
An overall improvement in receiving water quality as a result
' of reduced pollutant loadings from CS
-------
under a split-flow mode of operation, whereby 100 MGD is oassed
through the settling and biological processes units with thlr
iVMM
overall quality of the final plant effluent is better than if
the split-flow mode of operation was not conducted.
System Regulation
-------
laboratory testing of permeability rates of porous pavement indica-
ted that repealed loadings of sand are required to induce a signi-
ficant reduction in permeability. Even after loadings simulating
6 5r of adding roadway abrasive materials, the permeability rate
exceedld the highest rainfall intensities likely to be observed.
The Lake Avenue porous pavement demonstration site showed that
liqnificant clogging (reduction of 94% from initial permeability
rates) of porous pavement can occur if overland runoff carrying
sediment is allowed to pass onto the pavement. The structural i n-
tegHty of the porous pavement at this site remained unimpaired
under heavy and frequent traffic loadings.
fi ThP rost of constructing a porous pavement parking lot utilizing an
impermeabll membrane and underdrains $18/yd2 is slightly higher
SS of a conventionally paved lot with storrnwater inlets and
subsurface piping $16/yd2. If subsurface soil conditions are aae
quate to allow passage of the rainfall that infiltrates through the
pTrous pavement! then the impermeable membrane and underdrains are
not needed and costs for both types of pavements would be the same.
Trunk Sewer Eva! nations
1 Field inspection of the West Side Trunk Sewer (WSTS) from Alice and
G ide Streets to Glenwood Avenue and Malvern Street indicated that
the original tunnel is in good condition. No significant structur-
al deficiencies or excessive sediment accumulations were observed.
2 The East Side Trunk Sewer (ESTS) inspection indicated" that slgnifi-
' cant grit has accumulated in the brick pipe section of the ESTS
from Edge! and and Rocket Streets to Waring Road and Norton Street
The grit depth varied from 12 to 24 in. Within this section of the
ESTS the sewer size varied from 5.5 to 6.0 ft in diameter.
3 Major structural deficiencies were observed in the unfinished rock-
tunnel portion of the ESTS along Norton Street. Excessive sediment
and debris were noted in the ESTS immediately east of both Portland
Avenue and Clinton Street. Significant spaulling was also observed
at numerous locations in the ESTS along Norton Street. These fac-
tors contributed to a loss in potential in-system storage volume of
about 20% and in conveyance capacity of approximately 65/6.
4 The total estimated in-system static storage volume is 3.5 MG,
which can be effectively utilized only after the installation of
control structures/regulators at various locations within the
existing conveyance system.
-------
SECTION 3
RECOMMENDATIONS
3B"?at1vetto Best^Ma °f thl'S 1nves^'gat1on' the following recommenda-
lution control are presented: C°m 1ne sewer Overf1ow pol-
General
1. Thorough investigations of BMP options should be conducted prior to
adoption and miplementation of capital-intensive structural alter-
natives.
2.
7.
8.
l1mTanHalhty Jf%?hou1d be collected to define urban runoff prob-
lems and the effectiveness of various BMP abatement measures.
3. Intensive efforts should be expended in post-implementation evalua-
tions of adopted BMP abatement measures to determine their effec-
5 *
-
TSSUl^S !h?u1d rec°9ni*ze t^t a reduction in capital
ni? °Jle"ted program will require a long-term com-
'"" ma1ntenance - order to
. 0 Construction G^a"^ review and approval
5. USEPA and state agencies should give strong consideration to fund-
CSO Ve S°UrC6 a"d collection s^steni management options for
The method of operating treatment facilities under a split-flow
mode should be adopted for facilities having little or no wet-
weather capacity. The USEPA should review treatment plant efflu-
ent percent removal requirements.
A handbook for implementation of BMP measures should be prepared
and distributed to allow practitioners to assess the applicability
of such measures for their specific needs. "^mnty
Consideration should be given to the utilization of porous pavement
in redeveloping residential, commercial and industrial parking
areas. A thorough evaluation of existing soil conditions is re-
quired.
10
-------
-
which can result in basement backups as well as CSOs.
cn.
Sise UP measures thai are intended to maximize the use of the
existing systems.
f
measures should be conducted For example, sudge
system improvements.
12 A water quality monitoring program should be established to provide
briinTti^^^
grams.
i3- rt&:oshK^^^
ditcharal concentrations apart from overall percent removal re-
y
capabilitie? under increased hydraulic loadings encountered
storm events.
Specific to Rochester, New York
1 The overflow and in-system flow monitoring data acquisition system
' should be maintained and operated for the purpose of:
Determining the frequency and magnitude of CSOs dis-
charging to the Genesee River.
Identifying those sections of the trunk and intercepting
• ewer sy ?em that are not fully utilized during storm
events to allow further readjustment of regulators and
weirs to optimize system operation.
The oresent rain gauge system does not need to be further maintained
Ind Spera?ed A more sensitive rain gauge monitoring system will
be retired for overall CSO system control to be implemented under
other ongoing programs.
2 The identified flow-restrictive segments of the SPBI should be up-
qraded so that an optimized, self-consistent flow regime can be
maintained in orderto reduce overflow to the Genesee River. A
11
-------
USEPA Construction Grants Step 1 study was received by the Rochester
Pure Waters District. Step 2 funding should be sought. Kocnester
3. The Frank E. VanLare Treatment Facility should be operated under a
split-flow mode of operation to maximize treatment of wet-weather
flows, thereby minimizing the impact of plant effluent on the
Rochester Embayment of Lake Ontario. The plant's permit should be
J ter^ *° eliminate the 85% removal requirement to allow the needed
flexibility in plant operation which would result in enhanced plant
effluent quality. The 30-30-1 (BOD, TSS, TIP) requirement should
oe maintained.
4. The East Side Trunk Sewer (ESTS) should be substantially rehabili-
t*ted between Jewel Street and Waring Road. That portion of the
ESTS from Waring Road to Garson Avenue should be cleaned to remove
excessive grit deposition. After rehabilitation, CSOs presently
discharged to Irondequoit Bay from the ESTS will be substantially
reduced. A USEPA Construction Grants Step 1 study was received by
the Rochester Pure Waters District. Step 2 funding should be
sought. Periodic tunnel inspections should be part of the overall
improvement program.
5. Further analysis should be conducted on the potential use of ESTS
in-system storage. Work should include consideration of by-pass
volumes at Atlantic and Garson Avenues and at Densmore Creek After
rehabilitation, evaluations should again be conducted to determine
the additional in-system storage volume realized.
6. A continuous review of wastewater levels in the major trunk sewers
should be made to insure that, as a result of the modified overflow
regulators and weirs, adverse backwater and surcharge conditions do
not occur during periods of rainfall.
7. Review of the effectiveness of the implemented regulator/weir modi-
fications should be continued. Consideration should be given to
replacing the hardware that was installed on an interim basis with
permanent controllable gates. A USEPA Construction Grants Step 1
study was received by the Rochester Pure Waters District. Step 2
funding should be sought.
8. Consideration should be given to keeping the identified high-
polluting industrial discharge associated with the Carthage drain-
age area within the trunk and intercepting sewers, and not allowing
it to become part of the CSO from this service area. Although
structural improvements will be necessary to accomplish this, in
the interim prior to construction of required facilities, the
Carthage regulator should be modified by removing the orifice
plate/float mechanism. This would result in an immediate increase
in the wastewater transfer rate to the SPBI of 8 cfs (5 mgd) or a
47% increase over the present transfer rate.
12
-------
10.
11.
= '^^^
Ss The current level of street cleaning effort is adequate.
ThP mrrent levels of sewer cleaning and periodic sewer maintenance
provideS Ey ihe Rochester Pure Waters District should be continued.
should be given to the use of porous pavement in all
oroiects involving parking areas. A site-specmc
ty review should be conducted as part of each appli-
cation.
19 Further field testing of Hydro-Brake static flow regulators should
12. rurtner neiu ussumy ^ «,/_____ __c _ ,,,„, ,.,,-^Q imniomontat.ion oro-
Further fie esng o -
be cSnSucled pHor to adoption of a area-wide implementation pro-
gram.
moderation should be given to the use of inlet control devices as
a means of Educing the peak stormwater inflow rate into the sewer
collection system This should be done after a site-specific re-
5lel of the potential for storing additional stormwater runoff in
the streets and gutters.
control devices with associated instrumentation should be
d Jn ?he combined sewer system at the following locations:
Norton Street and Portland Avenue
Norton Street and Waring Road
East Side Trunk Sewer at Jewel Street _
Lexington Avenue Tunnel at the overflow regulator
West Side Trunk Sewer at the overflow regulator
Front Street Sewer at the diversion point to the inter-
GeKesee Valley Interceptor Southwest at the connection to
the Clarissa Street Tunnel
A USEPA Construction Grants Step 1 study was received by the
Rochester Pure Waters District. Step 2 funding should be sought.
effectiveness of the implemented BMP measures. Such programs
IhoSld be lundable under the USEPA Construction Grants program.
13
-------
SECTION 4
STUDY AREA BACKGROUND
GENERAL
The City of Rochester, county seat of Monroe County, is located in the
western portion of New York State and borders on the south shore of like
?n St?n s5owJhin1F;9ure 3' uThe mi°r receiving water bodies in the area,
in addi to the. lake, are the Genesee River, which roughly bisects the
. , e
?^' ?2d Jr?n^«oit Bay, which lies to the northeast. The city occupies
oflhe ci?v ?
-------
Figure 3. Study area location map.
15
-------
socio-economic problems for which substantial efforts by various governmental
agencies have been made to identify the extent of the problems and to imple-
ment measures to mitigate their impacts. Goals have been established by
Monroe County, the New York State Department of Environmental Conservation,
6 SE'
and6 alroale0n ^ *»*™"'"* *"** Commission,
trpatlHe;,0HeraI1 Pr°f am f°r^he abatement of water pollution resulting from
treated and untreated sewer discharges was initiated in the 1960's with the
upgrading and expansion of the treatment plant for the City of Rochester and
surrounding area. Concurrently, comprehensive sewerage studies were con-
?nS!5 f;r™rio"s Portions^ Monroe County including the city. It was the
intent of this planning activity to develop an effective county-wide pollu-
tion abatement program. H«"U
In September, 1967 the Monroe County Pure Waters Agency was formed to
coordinate the completion of the various comprehensive sewerage studies The
recommendations that followed the completion of these studies included a wide
range of abatement measures; however, various legal and institutional con-
straints prevented their immediate implementation.
A separate comprehensive study was then authorized by the New York State
Department^ Health to finalize the work that had not been completed This
comprehensive sewerage study for the City of Rochester was released in 1969
and formally completed in 1970 (6). The study showed that CSOs from the City
of Rochester occurred over 100 times annually. On the basis of available
Q*™ ?ue ann]T1atVe caPacity of tne Genesee River was calculated to be
8,
-------
Bay.
plan into an east side of the city CSO abatement plan.
The analysis compared the economics of the multiple holding tank plan
with those of deep tunnel storage and conveyance for achieving the desired
Tunnel was Increased and the east side holding basins were eliminated.
T^n Hptailed drainage basin studies were also completed in the early
1970s They ie?e the East Side Trunk Sewer Study and the Engineering Report
for the Genesee Valley Interceptor (8,9). From these studies, ind^vi^al
projects have been identified and have advanced to final design and con-
struction.
In the mid 1970's a Wastewater Facility Plan (WFP) was completed that
study were used in formulating the Wastewater Facility Plan.
The WFP reported that:
1 The water quality of the area's receiving waters was being adversely
affected byCSO's from the Rochester Pure Waters District. The
U I IW^WN*** "" V
overflows contributed to:
a The eutrophication of Irondequoit Bay,
b'. The depression of dissolved oxygen levels in the lower
Genesee River, and
17
-------
I
c. The bacterial contamination of Lake Ontario beaches.
2. The sewer network was inadequate to convey the stormwater flows
being generated from the present urban environment. The resulting
localized surface and basement flooding, caused by backflow of
combined sewage, was a public health hazard.
3. Major structural improvements to the sewerage system were needed
a. Consistently meet the water quality objectives of the study
area's receiving waters, and
b. Improve the conveyance capacity of the sewer network to reduce
flooding and the associated public health hazards.
4. Minimal and nonstructural alternatives would not solve the identi-
fied problems but may serve to enhance the beneficial effects of
structural alternatives.
5. The most cost-effective structural improvement for CSO pollution
abatement was a tunnel storage/conveyance system.
6. The storage/conveyance system was also the primary element of the
plan for upgrading the conveyance capacity of the sewer network to
reduce flooding.
In view of the short time frame required for implementation and the
modest capital costs associated with a number of minimal and nonstructural
alternatives, the Rochester Pure Waters District applied for and received a
Section 108 grant from the USEPA Great Lakes Program, Region V to further
evaluate and demonstrate selected BMP measures. The resulting BMP program
demonstrated the general cost-effectiveness of implementing BMPs to reduce
the frequency and volume of CSO on an annual basis. It was intended as an
interim program to abate pollution while long-term design and construction
of recommended structurally-intensive programs were completed. The manage-
ment options identified herein as most effective in reducing CSO discharges
were supplemental and completely compatible with the ongoing structurally-
intensive abatement programs, "'any
DRAINAGE AREA DESCRIPTION
The combined sewer system of the City of Rochester is the focus of the
BMP program. All of the present CSO discharges to the Genesee River and
Irondequoit Bay originate within city limits. Numerous stormwater outlets
also discharge to these receiving water bodies. The various drainage basins
and the areas tributary to them are shown in Figure 4. Table 2 summarizes
the location and size of the drainage areas within the city tributary to
each major receiving water body.
18
-------
LAKE ONTARIO
LEGEND
TRIBUTARY TO LAKE ONTARIO \\\
TRIBUTARY TO IRONDEQUOIT BAY + + + j
TRIBUTARY TO GENESEE RIVER
FROM WEST ooo
FROM EAST AAA
Figure 4. Drainage areas within the City of Rochester.
19
-------
TABLE 2. ROCHESTER DRAINAGE AREA!
Tributary To
Lake Ontario j QOO
Genesee River (from the west) 10*700
Genesee River (from the east) 3*100
Irondequoit Bay 7*800
Total 22*,600
The major subbasins within the City of Rochester of concern to the BMP
study are showrMn Figure 5. The number of each drainage area corresponds
to overflow monitoring site number as described in subsequent sections. Much
Of the data assnnat.Pri unth «^ of these drainage areas were compiled upder
a orpvinu ,nHvn -
Tables 3 Ld 4 characteristics of each area are summarized in
SEWER SYSTEM DESCRIPTION
As previously stated, the Rochester wastewater collection system is, to
Llar"e7i/91-ee' a c°mbmed sewer system. Of the total service area, approxi
mately 75% is served by combined sewers. In general, the existing sewer net-
work follows the natural drainage of the region. Figure 6 show the majo?
trunk and intercepting sewers within the City of Rochester.
All of the trunk sewers serving the tributary area flow toward the
eMher> ,Imf ?Jat6ly Pn'or to the river> ^'version structures are pro-
at the end of the trunk sewers to divert flow into the SPBI Excess
stormwater flows generated during periods of rainfall and snowmen discharge
as CSO s to the Genesee River and Irondequoit Bay at the locations shown in
Figure 1. The wastewater is then conveyed in a northerly direction to the
Frank_E. VanLare Treatment Plant (VanLare STP) located adjacent to Lake
Ontario. This plant provides primary settling and biological treatment
The design parameters for the plant are as follows:
Design Process Flow 100 mgd
Maximum Hydraulic Flow 200 mgd
BOD Loading 300 mg/1 - 250,000 Ib/day
Suspended Solids Loading 300 mg/1 - 250,000 Ib/day
The SPBI was designed to convey all of the dry-weather flow from the trunk
sewers_and two and one-half equal volumes of stormwater. Combined sewage
flows in excess of this quantity discharge into the Genesee River. CSO dis-
charges occur regularly, the frequency and volume of such overflows being
directly related to rainfall intensity.
Most of the overflow regulators are automatic devices that operate by
means of a float-activated orifice plate which controls the rate at which
wastewater is transferred from the trunk sewer to the conduit leading to
the SPBI. Adjustment of the float mechanism allows for various discharge
rates. Associated with each overflow structure is also a weir located within
20
-------
LAKE ONTARIO
Figure 5.
Major subbasins tributary to Genesee River within
City of Rochester.
21
-------
Drainage Area
No.
7
10
11
21
27
31
36
22
Area
ac
729
988
2682
826
810
569
348
1169
SFR*
610
339
1407
348
644
434
0
821
MFR+
7
22
0
10
0
0
91
52
.••• v/i i_iuiu> UJL. onrmni, i crvio I it,o
Land Use - ac
Commercial
53
32
109
318
72
38
257
200
— _
Industrial
18
465
994
50
55
27
0
20
Open
41
130
172
100
39
70
0
76
Ave. Land
Slope
0.0118
0.0066
0.0060
0.0059
0.0073
0.0070
0.0080
0.0100
% Imp.*
48.2
46.4
49.2
66.1
44.9
52.9
80.3
42.0
ro
ro
*SFR = single family residential
MFR = multi-family residential
*% Imp. = percent imperviousness
TABLE 4.
— V"-"-1- •*•• JunnniM ur UKmiMMbt MKtA CHARACTERISTICS
Drainage Area
No.
7
10
11
21
27
31
36
22
Dwelling Units
4653
2016
9919
4397
6333
4596
0
9444
Population
18476
5522
27296
13687
17540
14332
(12700)*
35088
Catchbasins
911
574
2357
(826)*
1339
(626)*
(435)*
(1400)*
— . _ — ,
Gutter 9
Length - x 10
2020
1350
6480
(2800)*
2900
(1450)*
(650)*
(3600)*
—
*Values in ( ) indicate extrapolated or assumed data based on the other drainage areas.
-------
LAKE ONTARIO
Cross
Irondequdj
Tunnel
Figure 6. Network of major trunk sewers and interceptor for
City of Rochester.
23
-------
stvaJ ! 55' " *h 2ln^ at tne intersection of Central Avenue and Water
Street and terminates at the VanLare STP, is about 7.9 mi long and was con-
structed by various methods. For the most part, the interceptor consists of
circular brick conduit. Although the size varies, the diameter varies
generally from 5.5 to 8.0 ft. uiameter vanes
The SPBI normally flows from one-third to one-half full, but durina
periods of rainfall,.It flows approximately three-quarters fun Conveyance
capacity within the interceptor generally increases towards the treatment
hldra,'n i> ?„ ?Cai °n °f the SPBI 1S Sh°Wn 1n Fi9Ure 7- "9ure 8 shows ?he
nXf S f"l -flow conveyance capacities within the SPBI along its entire
reach'nJr ?hl t^J" ^ 1lntrce?tor reach 12 to 14 ft/s<* in the lower
range of 3 to 5 ft/lie ^^ '" ^^' h°W6Ver' velociti" ™ in the
The major trunk sewers within the overall wastewater collection system
the BMP prog™a-identified«*>"o»"isr
the BMP
"6 6:
(1) Dewey-Avenue
(2) Lexington Avenue
(3) West Side Trunk Sewer (WSTS)
(4) Spencer Street
(5) Platt Street
(6) Front Street
(7) East Side Trunk Sewer (ESTS)
(8) Genesee Valley Interceptor Southwest (GVISW)
(9) Inner Loop
IoLWSISian
-------
LAKE ONTARIO
Figure 7. Location map for St. Paul Boulevard Interceptor.
25
-------
VANLARE
STP
275-295 cfs
(178-191)
Ridge Road
305 cfs (197)
ESTS
WSTSD Siphons
78 cfs
(5.0)
Spencer St.
134 cfs (87)
Carthaae
15 cfs
(10)
'SPBI Siphons 70 cfs (45)
'Cliff Street
100 cfs (65)
Mill a Factory
105 cfs (68)
90 cfs
Central 8 Front (58)
NOTE: Values in ( ) are
flowrates in MGD
32 cfs (21)
Central a N. Water
Figure 8. Schematic of the SPBI and trunk sewer system.
26
-------
The Genesee Valley Inte.cep^Sout^sttunne, locate, in^he south-
western portion of *h! "ff'J!!! -strict Tunnel, then to the Main and Front
system dnscharges to ^Clarissa Stree t u nn , ^^ regulator.
SB^f a'rrgeVnne/Sp^ra "Substantial a^unt of potential in-syste™
storage is available.
vey a portion of the CSO from the ESTS.
Within the overall wastewater collection system, there are ten grit
the access manhole.
d resuU
discharged to the Genesee
River would be reduced.
syslem storage wSuld be realized and overflows would be reduced.
WATER QUALITY CONSIDERATIONS
body and the expected impacts due to -CSO's follows.
27
-------
N
LAKE ONTARIO
Chambers on Combined
Chambers on Storm Sewers
Severs
Figure 9. Grit chamber locations,
28
-------
for tKtnM»r! STJlX'^^^M"^^™°*
ing conclusions were formulated (2):
of estab-
e
treaSt facilities are required to meet the water quality stan-
dards of the Genesee River.
* fSO treatment efficiencies in the range of 90% to 100% are required
3' to maintain the dissolved oxygen standards of the river during
summer low flow periods.
several days after an intense storm event.
lakP Ontario and specifically the Rochester Embayment are classified as
'A-Spec al ' ly The Sew ?Sk State Department of Environments Conservation.
in excess of established standards occur during storm events (2).
™*
and Is no» being
29
-------
csos
RECEIVING MATER BODY
TABLE 5. WATER QUALITY OBJECTIVES
PRIMARY OBJECTIVE
Genesee River
°f
Irondequoit Bay
Maintenance of the dissolved oxygen
standard—minimum 4.0 mg/1 ; average
daily 5.0 mg/1 a
Maintenance of the established fecal
coli form standard-200 counts/100 ml
Maximurn reduction of nutrient loadings
30
-------
SECTION 5
OVERFLOW MONITORING
Flow Monitoring
^^^wf-^^rcsH^H^""
sp i^$ss$ S£?s B="is rr
more reliable equipment.
In terms of field Installation, an ultrasonic or bubbler ^vel.measunnj
primary measurement.
31
-------
LAKE ONTARIO
CSO Discharge and
Site Number
Figure 10. CSO monitored sites within the City of Rochester.
32
-------
Figure 11. Head measurement for open-channel monitoring location
Figure 12. Head measurement for weir monitoring location
33
-------
Location
TABLE 6. OVERFLOW MONITORING INSTALLATIONS
Site
Flow Monitoring
Equipment-Type Telemetry Sampling
Maplewood
Seth Green
WSTS
Lexington
Carthage
Spencer
Mill & Factory
Front
Central
7
27
11
10
31
17
21
22
36
Ultrasonic
Bubbler
Ultrasonic
Ultrasonic
Ultrasonic
Ultrasonic
Bubbler
Ultrasonic
Ultrasonic
Yes
Yes
No
Yes
Yes
No
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
Yes
Yes
Yes
Location
Maplewood
Seth Green
WSTS
Lexington
Carthage
Spencer
Mill & Factory
Front
Central
TABLE 7.
Site
7
27
11
1.0
31
17
21
22
36
CHARACTERISTIC FLOW EOIIATTONS
Type Flow
Equation
Open Channel
Open Channel
Open Channel
Weir
Weir
Weir
Weir
Weir
Weir
Size and Shape of
Conduit*
5'H x 6'W Rect.
6.83' 0
7.92' x 8.5' H.S:
?' <; F
/ o . t. .
7' S E
4.75'H x 3.5'W B.H.
7' 0
8.5'H x 8.17'W B.H.
9'H x 10.5'W B.H.
*Rect. = Rectangular, 0 = circular, H.S. = Horseshoe,
S.E. = Semi-elliptical, B.H. = Basket-handle
Primary and secondary recording systems were utilized at most overflow
monitoring locations to insure reliable system performance. The primary
system involved the use of telemetry instrumentation to allow the site
measurement to be transmitted via telephone lines to a central receiving
SSJSTi i f°5%SlJeS °SSrj?d With telemetry ^ems transmitted the moni-
tored level data to a PDP-8E computer manufactured by the Digital Equipment
Corporation, >Which was located at the VanLare STP. A schematic of the over-
Tiow monitoring and telemetry systems is presented in Figure 13.
The secondary or backup data recording system involved individual Rus-
trak recorders located at each site. During times when the telemetry system
was inoperative, flow data were recorded and retained on chart paper. With-
out this secondary system, a significant amount of data would have been lost
A backup recording system should be installed on overflow conduits during any
long-term monitoring program. *
34
-------
CO
en
-s
n>
o
ra-
ft)
o
o
-h
(D
-h
O
±3
_j.
d-
O
-S
cu
Q-
rt-
(t)
a
fD
FIELD STATION
CENTRAL RECEIVING
LOCATION
4-20 MA
Signal
Ultrasonic
or
Bubbler
Level Monitor
OVERFLOW
CONDUIT
Telemetry
Transmitter
Tone
ire
Transmission
4-20
MA
Sampler
trip-
Sampler
Activation
Telemetry
Reciever
,,4-20 MA
Converter
,,0-10 v
Computer
OUTPUT
(Flow Values)
(Characteristic Flow
Equation)
-------
Sampling
Samplers were installed at every overflow location exceot ncpr
^^^^
^
located in the overflow conduit, which would trip a relay activating the
sampler when the depth of flow reached a pre-determined level
The overflow samples were collected at approximately 15 min intervals
*ah St eve?*a11 samPles were collected and sent to Ihe O'Brien
' SUbSequent
Category
TABLE 8. OVERFLOW ANALYSIS srHFnm F
11
Parameters
Oxygen-demanding
Bacteria
Solids
Nutrients
Metals
Misc.
Biochemical Oxygen Demand
Total Organic Carbon
Total Kjeldahl Nitrogen
Total Coliform
Fecal Coliform
Fecal Strep
Total Suspended Solids
Volatile Suspended Solids
Ammonia Nitrogen
Nitrites
Total Inorganic Phosphorus
Iron
Chromium
Lead
Manganese
Mercury
pH
Chlorides
36
-------
The purpose of the overflow monitoring and sampling program was four-
fold:
01
R&D program.
determined under the present program.
eta
the scheduled regulator and weir
. SUSSfSS
S~ !Sir~.!f K S.S i. S«£»«i» ...i~. «» .««n.««.
of the BMP program.
factory data collection during storm events.
system.
previously indicated, it was not the Purpose OT we BHK p y assessing
r ,.1 -• j. _ ,~.: « ^, i-ivninvam hllT fin I V TAJ USc LIIC UU I I cv- v.&" «»»««•
measures.
37
-------
RAINFALL ANALYSIS
,pf ,nH nn?iTV?P°?ant tactors in the generation of storm-induced
ies and Dollutant loadmnc ic vain-Fan AH o-u-j. ^..^ _.. ..
1S ra1nfa11'
ii
An
oe
fall data, which was then utilized for CSO loading projections
statit ho M records from the U.S. Weather Bureau
R*?niS?i ^e Monroe County Airport were used in evaluating BMP options
Rainfal records covering a period from 1954 to 1975, were obtained from the
National Climate Center, Asheville, North Carolina. The data indicated that
precipitation patterns and durations for the Rochester area were highly var-
iable. High-intensity, short-duration events were usually associated with
thunderstorms which occurred during the summer months; whereas^ ow intensity
long-duration events were usually associated with cyclonic act v tj which
occurred d 1-nvn.y wmcn
occurred during the spring and fall months.
99 vnf 9 ™a"H'zes the m°nthly and annual rainfall statistics based on
22 yr of precipitation records collected during the period of January 1954
'
davs'wUh nrpJ n-; t'" ^If' T^b1eS 10 and U Su™"ar1ze the n of
P^P^tion and the rai
/•tax/** i./-i 4- U «««^ .: _ * j_ j» i . i . «w.i MI is* i IA.W uiic nuiiuci Ul
record P^^P^ation and the rain per day associated with the period of
JABLE 9. AVERAGE MONTHLY RAINFALL IN THE ROCHESTER AREA -
Month
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
ANNUAL
Average
Rainfall, in.
2.11
2.45
2.36
2.58
2.65
2.81
2.30
3.31
2.29
2.52
2.76
2.50
30.63
Standard
Deviation
0.87
1.10
1.01
0.83
1.20
1.61
1.23
1.26
1.14
1.81
1.12
1.10
4.43
Coefficient of
Variation
0.41
0.45
0.43
0.32
0.45
0.57
0.54
0.38
0.50
0.72
0.41
0.44
0.14
95% Confidence
Level Interval!
0.39
0 49
0 45
0.37
0 53
0 71
0 55
0 56
0.51
0.80
0.50
0.49
1.97
38
-------
Month
-
Jan
Feb
Mar
Apr
May
Jim
Jul
Aug
Sep
Oct
Nov
Dec
ANNUAL
Average No.
of Raindays
_
15.64
14.77
13.82
12.91
11.59
9.41
9.23
10.18
10.00
11.05
15.18
17.73
151.50
Standard
Deviation
Coefficient of
Variation
95% Confidence
Level of Interval!
3.16
3.70
.62
.74
.42
,22
,12
,13
.80
,12
.92
3.
2.
3.
3.
3.
2.
3.
3.
2.
3.15
0.20
0.25
0.26
0.21
0.29
0.34
0.34
0.21
0.38
0.28
0.19
0.18
0.09
1.40
1.64
1.61
1.22
1.52
1.43
1.38
0.94
1.69
1.39
1.30
1.40
5.73
TABLE 11.
12.91
AVERAGE MONTHLY RAIN PER STORM IN THE ROCHESTER
AREA - 1954 to 1975
Month
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
ANNUAL
Average Rain
Per Storm
in.
0.14
0.17
0.17
0.21
0.23
0.29
0.26
0.33
0.23
0.21
0.18
0.14
0.21
Standard
Deviation
Coefficient of
Variation
95% Confidence
Level Interval±
0.05
0.07
0.05
0.07
0.09
0.12
0.13
0.11
0.10
0.12
0.06
0.06
0.02
0.40
0.40
0.31
0.33
0.37
0.41
0.51
0.33
0.43
0.55
0.34
0.43
0.20
0.03
0.02
0.03
0.04
0.05
0.06
0.05
0.04
0.05
0.03
0.03
0.11
0.01
39
-------
RnrJ^ Tabljs. 9 through 11, it can be seen that monthly precipitation in
Rochester was fairly uniform throughout the year. As expected however the
months of June, July and August exhibited the higher intensity,' shorter'dura
tion storm events. During the same period of record, the greatest total
amount of ra nfall presented by a storm event was 3.91 in.9over 87 h? The
ctnv. A ra1"fa11 characterization routine was utilized to define discrete
nS HatT! %S?d rank deS1'9n Parameters associated with each storm The in-
put data to this program was the hourly rainfall record from the US SLthPr
Bureau. For this study, a discrete storm event was defined as starting with
the first measurable rainfall after a minimum interval of 6 hr with no ra n-
fall and ending when a gap in measured rainfall of at least 6 hr was first
encountered For each event in the historical record, the following llrlL
P?rn«r?-CalSUlat£: dat6' Startin9 hour' duration/total ran?afl,P?he
elapsed time from the previous storm, snowfall, and the ratio of the hour of
ST rT£a11 t0 t0tal durat1on Cr value>- Fi9ures 14 through 17 a?e
nrnSf ^^^^ curves b«ed on ranked rainfall data as p'ov ded by the
program Storm parameters can be determined from these curves The validity
aa5ailabl±Pern f ^ ^ mS d^C"y related to the "Ingth of the ^
available record Figure 18 presents the rainfall intensity-frequency-
duration curves for Rochester as determined from the U.S. Weathe? Service
RMP Jal?leS.12 and-15 summarize rainfall data in the Rochester area for the
data for 1S7S9iK? H^H ?"!%? 1979^° 'August 1980' An examination of
data for 1979 indicated that 1979 was slightly higher in total precipitation
t velvndrveLa^hfarnfal -h°U^ MarCh' June> August and November^er^rela-
tively dry months. Of significance was that over one-third of the total an
nual precipitation in 1979 was accounted for by the 12 storms Indicated T
storm which occurred on September 13-14 accounted for 3.54 in. of the monthly
total precipitation of 5.32 in. Examination of the 1980 prec pitation data
showed that 1980 had approximately the same amount of prec^pUation as an
average year, even though 6 of the 8 months had below average precipitation
This was further highlighted by the quantities shown in Table 14 The monJh
of June contributed over 20 percent of the total precipitation through
and 7 hnth T U^ ?• *P ^Jge 5t°mS whl'ch occurred back-to-back on June 6
and 7, both of relatively short duration considering the total rainfall depth
Such events as indicated in Tables 12 and 13, were anticipated to have P
major impacts on the conveyance network and contribute greatly to the dis-
cnarge of GSO.
In subsequent modeling of the conveyance system for the City of
Rochester with the Simplified Stormwater Model (SSM), an average rainfall
year was used. That is, a particular year (1975) was selected that had a
volume9™ PreciPntation amount approximately equal to the average annual
40
-------
O.I
0.2 0.4 0.6 I ^ 4 6 8 10
OCCURRENCES PER YEAR
20 40 60801CO
Figure 14. Example curve - storm magnitude vs. frequency.
0.1 0.2
0.4 0.6 1 2 4 5 3 10
OCCURRENCES PER
20
40 6080 100
Figure 15. Example curve - storm intensity vs. frequency.
41
-------
ua
-s
n>
o x
c o>
-5 3
CD
.
O
C
-5
<
n>
PERCENT OF STORMS
DURATION OF STORMS, DAYS EQUALED CR EXCEEDED
<
CO
fB
n
n>
rr rj
O r*-
-5 O
-h
fu
-h w
r+ c+
fD O
C"
-S
l^ 3
H- CD
O X
i il'
ro
o
c
a>
a.
fu
rf
~j,
O
3
-h
-S
n>
xi
e
a>
3
o
O) CD O
-------
55
ui
20.0
15.0
10.0
8.0
6.0
4.0
2.0
1.0
0.8
0.6
0.4
0.2
O.I
0.8
0.6
Base Curves Obtained From United States Weather
Service Technical Paper No. 25
J_
10 15 20 30405060
Minutes
DURATION
456 8 10 12
Hours
18 24
Figure 18. Rainfall frequency-intensity-duration curves
for Rochester, New York.
43
-------
TABLE 12.
Month
— — •» — •— — ~_ __
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
ANNUAL
n—
Total Prec.
in.
4.18
2.40
1.76
3.78
3.14
1.85
3.16
2.05
5.32
2.60
1.00
2.86
34.90
Annual Avg.
Prec.* in.
2.11
2.45
2.36
2.58
2.65
2.81
2.30
3.31
2.29
2.52
2.76
2.50
30.63
—
Date
Jan 24-26
Feb 25-26
Mar 29-30
Apr 6
May 24
Jun 7
Jul 31
Aug 26-27
Sep 13-14
Oct 5
Nov 26
Dec 24-26
— — — — — — — ^— ™ _
*Period of Record 1954 to 1975
tai Hrec.
in.
•~"
1.33
0.90
0.37
0.86
0.63
0.34
0.70
0.63
3.54
0.84
0.38
1.60
12.12
Duration
hrs
— ' _
42
21
6
21
6
2
4
12
16
21
7
44
Snow
Incl
Yes
Yes
No
Yes
No
No
No
No
No
No
No
No
£BgCI^ITATIONJAIA_IN ROCHESTER AREA - 1980
Month
.._
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
ANNUAL
(to Aug)
Total Prec.
in.
1.11
1.16
3.83
2.35
1.49
6.77
1.90
2.68
21.29
Annual Avg.
Prec.* in.
2.11
2.45
2.36
2.58
2.65
2.81
2.30
3.31
20.57
— — — — — — — __
Date
Jan 11
Feb 16
Mar 21-22
Apr 28
May 31
Jun 6
Jun 7-8
Jul 22
Aug 5
Aug 5-6
Largest Storm
lotal Prec.
in.
0.38
0.34
1.20
0.99
0.47
2.19
2.16
1.03
0.72
0.60
10.08
•**•'
in Month
Duration
hrs
11
17
43
12
2
4
3
16
1
6
Snow
Incl
No
Yes
Yes
No
No
No
No
No
Nn
No
— •
*Period of record 1954 to 1975
44
-------
en
TABLE 14.
Month
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
I
Avg.
Rain, in.
2.11
2.45
2.36
2.58
2.65
2.81
2.30
3.31
20.57
i
COMPARISON OF ANNUAL AVERAGE RAINFALL DATA VERSUS 1980 RAINFALL DATA
Avg. Rain
Days/Mo.*
,
16
15
14
13
12
9
9
10
, — — •
Avg. Rain
Per Rain Day
— •
0.13
0.16
0.17
0.20
0.22
0.31
0.26
0.33
Standard
Dev, in.
0.87
1.10
1.01
0.83
1.20
1.61
1.23
1.26
•-"•
1980
Rain, in.
1.11
1.16
3.83
2.35
1.49
6.77
1.90
3.22
21.83
No. Rain
Days/Mo.
15
18'
16
14
9
15
10
10
Avg. Rain
Per Rain Day, in.
0.07
0.06
0.24
0.17
0.17
0.45
0.19
0.32
No
. of days per month in which precipitation (water equivalent) was > 0.01 in.
-------
ec?edd?ain?alf daX that^" ^T" Prec]P1tat1on data, local rain gauges
ecrea raintail data that was subsequently used in the overflow mnnitn^-in
sis. The Wea
e n e overow mnnitn-inn
ana ysis. The Weather Bureau data base served to assess the effectTSpnp««?
imp emented BMP measures on an average basis. With respect to oSerfloS Snl
"
. oero nl
d?ari-na9cPharVer' the/ctuaj CSO dis^arge volumes and raes from ?he variou
drainage areas were directly related to site-specific rainfall intensitiP?
and volumes If rainfall within the City of Rochester was not uniform then
tmentW ' ^ °Verfl°" "
assesl^l™ of
ysem
8 rain gauges had been installed within the Rochester Pure Wa?eVs District
Tanbler-15PidepVn?lf -C°mtb;ned S6Wer °Verfl°W "Storing and sampling program (1)
Table 15 identifies the rain gauge locations and Figure 19 depicts their lo
cation within the District. All rain gauges were Fischer Sorter bucket
"
enin 9aUgeS reCOrded
at five-minute intervals on punch paper tape for later transfer
SKoIlde9Sl ^ftaPr The aauges.were designed to initia data c
and provide transfer to punch tape in rainfall increments of 0.10 in.
TABLE 15. LOCAL RAIN GAUGES _
Location c-* Distance from Weather
LOCatlon Slte Bureau Gauge at Airport-mi
East High School
Marshall High School
School #44
Brighton Middle School
Fire Department Headquarters
Norton Densmore Chlorination
Station
Franklin High School
Charlotte Pump Station
RO-3
RO-4
RO-5
RO-6
RO-7
RO-8
RO-10
RO-11
6OC
. OD
c oc
3 . OD
200
. CL
R 79
3 . 1 £
4.71
R m
6.43
9.90
I10" ° 1S n?tw?^k of rain ^uges was continued under the BMP
w ?heV6r' T! S19nifjcant modification to the data reporting process
was made. The punch tape mechanism was removed from each rain gauge to per-
Slnfa?! 3SJ JJ JS" r ? ec*rical device to a11°w direct telemetering of
IJln 1 th th? cenra1lzed computer facilities at the VanLare STP.
Athough the processing of data was thereby expedited, backup local data re-
corders were sacrificed The lack of local recorded'data caY prove lo be
detrimental to a rainfall data collection program. If for any reason the
telemetry system did not operate satisfactorily, no useful rai^nfal? Sata
SiliSS Obtalned:. Local recording devices could avoid problems caused by
telemetry malfunctions. For most storm events, however, the local rain
gauges and the associated telemetry system performed adequately.
46
-------
xcz
§.»
I!
*Q -+
•3"
r> "•
O
to
o
I
|
*n
r
§
;o
a
3'
r
m
C5
m
o
IQ
C
-s
n>
fa
3
IQ
O>
C
03
O
O
O
3
fa
-------
! n,™S? 5 variability and distribution of rainfall in the Rochester
fi tLT? ? S-°rm 6VentS were exam1ned at those times when a minimum of
6 of the 8 local rain gauges were functioning properly. Total rainfall
depths were plotted on schematics of the Rochester drainage area at each
local rain gauge location and then iso-pluvial lines were drawn by interpola-
tion between the stations. Figures 20 through 22 present typical iso-pluval
curves as prepared using the above described procedure.
fn ^i9Mre P,, presents the distribution of rainfall over the study area
for the March .21, 1980 precipitation event. As indicated, the areas of
S1^ PreciP]tation occurred in the northeastern section of the study area,
A rL? *?! Precipitation ranging from 0.6 in. just north of the Monroe County
Airport to 1.1 in. in the vicinity of the VanLare STP. Since the local
?n £5nJn { 1ndlc^ed Precipitation in 0.10 in. increments, some variability
in rainfall recording resulted from the sensitivity of the gauges themselves
For the major portion of this storm, winds were out of the southeast at 10 to
15 mi/hr, but shifted dramatically to the west-southwest late in ?he day
The center of maximum precipitation appears to have been north of the down-
town Rochester area, although 0.84 in. was measured at the airport For all
gauges, the mean rainfall was 0.84 in. with a standard deviation of 0.17 in.
for thi9ln?v2^deiPQ«nS th? ra1nfa11 d1strib"tion Pattern over the study area
lhZ+ 5h« »ly 2S ?8° ear!y mon?ln9 event- ™e iso-pluvial lines indicated
that the areas of heaviest precipitation generally occurred in the vicinity
of the downtown area, ranging from 0.3 in. in the southeast to 0.6 in. along
a line from the airport, through downtown, to the VanLare STP The iso-
SJ™ll ™S f ire S°mPatible with the 0.58 in. of rainfall measured at the
airport. The July 22 storm was not a thunderstorm; however, the high mois-
ture content was evident by the 0.45 in. which fell in the first hour and
2« n Si K1C, -S ^ ^6 ^°nd h°Ur' For a11 9auges' the mean rainfall
was 0.33 in. with a standard deviation of 0.21 in. The airport data was
nearly double the average of the local gauges for this event. Winds during
this storm were from the southwest at 6 to 8 mi/hr.
A third example of the distribution pattern of rainfall in the
Rochester area is presented in Figure 22 for the June 26, 1980 event. This
event was classified by the National Weather Service as a thunderstorm tyje
event which lasted three hours. The iso-pluvial lines sketched in Figure 25
nfr^S1?? ? 5aSed °-udata fr°m the loca1 ra1n 9atJ9es- No overall pattern
of rainfall is discernible; rather, it appears as though the storm system
consisted of cells^of intense precipitation, which is typical of thunderstorm
activity. In the immediate downtown area, less than 0.1 in. of rain fell as
indicated by the 0.0 in. iso-pluvial line. This was consistent with the
overflow monitoring data for this date which showed no overflow. More than
? ? ' -lu fl1 inmediately west of the Genesee River, which again is consis-
tent with the monitoring data which indicated overflows from the Lexington
and West Side Trunk sites. According to the airport rain gauge, a total of
0.28 in. of rain was observed with a peak 60 min intensity of 0.20 in./hr
Because of the Accuracy of the local gauges, the iso-pluvial contours must be
considered estimates at best. For this storm, the mean rainfall for all
local gauges was 0.14 in. with a standard deviation of 0 12 in
48
-------
LAKE ONTARIO
LEGEND
|so - Pleuvial
Local Rain
CSO Monitored Discharge
Figure 20. Iso-pluvial lines for 21 Mar 80 storm.
49
-------
LAKE ONTARIO
LEGEND
-O.I—^ Iso-Pluvial Lines
(O.I) Rain Gauge Reading
^ Local Rain Gauge „,./'
A CSO Monitored
Discharge
CITY LIMITS
Scale: l"= 9100'
Figure 21. Iso-pluvial lines for 22 Jul 80 storm.
50
-------
LAKE ONTARIO
-0.1-
(0.1)
Iso-Pluvial Lines
Rain Gauge Reading
Local Rain Gauge
CSO Monitored
Discharge
Scale: 1=9100
Figure 22. Iso-pluvial lines for 26 Jun 80 storm.
51
-------
• * .PaTPles indicated that significant differences existed in
rainfal distribution patterns within the urban area, which was addressed in
evaluating the impacts of rainfall on CSO's. The March 21, 1980 storm indica-
ted that reasonable estimates of total precipitation had to be obtained for
cyclonic type events; however, such estimates for fast-moving, transient
events such as those of June 26, 1980 and July 22, 1980 had to be evil Sated
more closely before specific impacts on the collection system can be assessed.
A statistical correlation was also conducted for selected storm events
occurring between certain months. The results are shown in Table 16. For
the typical rainfall patterns associated with spring, there was generally
good correlation between the airport data and the local rain gauges. This
correlation decreased for storms which occurred during the summer months.
To establish long-term rainfall-CSO correlations a comparison of over-
flow volume based on airport rain data versus local rain gauge data was made
JirS H i0" wf Developed for the Central Avenue overflow (Site 36) us?ng
airport data and then a similar relationship was developed using local rain
gauge data from the Fire Headquarters location (RO-7). The resulting rela-
tionships are depicted on Figure 23. The small number of data points at the
upper end of the rainfall axis made assessment of the validity of the rela-
tionship between rainfall and overflow subject to a low degree of confidence
In the lower range of rainfall events, however, the data were somewhat con-
a Ion"-term bas* airp°rt data were rePresentative of the local rain gauge on
The correlations that were performed indicated that the rainfall distri-
bution for the City of Rochester varies widely for different storm events.
Because of this, the installation of eight local recording rain gauges
throughout_the city helped to more accurately determine the relationships
between rainfall and CSO at the different overflow locations than precipita-
tion data taken only from the U.S. Weather Bureau. It also showed that
cit can bfmisT ^ assumpt1on that ra1nfa11 Is uniform over the entire
OVERFLOW MONITORING
As_previously indicated, the overflow monitoring and sampling systems
were originally installed under the former R&D grant for the Rochester Pure
Waters District (1). During the BMP program, continuous upgrading of the
overflow monitoring systems was conducted. Specific improvements to the
monitoring system implemented as part of the BMP program included:
Incorporation of telemetry instrumentation into the local rain
gauges and the removal of the site recording strip charts. This
eliminated the need to change paper on the strip chart recorders
every two weeks.
Replacement of all Badger Meter, Inc. ultrasonic head and velocity
systems with portable ultrasonic head systems manufactured by
Manning Corporation. With these units, more accurate and reliable
52
-------
Rain Gauge
Distance From
NWS Gauge
at Airport
Number of
Data Points
Coefficient
of Correlation
East High School
Marshall H.S.
School #44
Brighton-Middle
Fire Headquarters
Norton Screenhouse
Franklin H.S.
Charlotte P.S.
East High School
Marshall H.S.
School #44
Brighton-Middle
Fire Headquarters
Norton Screenhouse
Franklin H.S.
Charlotte P.S.
East High School
Marshall H.S.
School #44
Brighton-Middle
Fire Headquarters
Norton Screenhouse
Franklin H.S.
Charlotte P.S.
Data for Storms March - August
34 0.55
8 0.93
27 0.77
25 0.53
18 0.72
16 0.42
17 0.61
27 0.59
Data for Storms March - May
15 0.86
2 1.00
13 0.90
n 0.76
13 0.82
10 0.86
12 0.71
15 0.86
Data for Storms June - August
19 0.54
6 0.94
14 0.80
14 0.50
5 0.71
6 0-07
5 0.51
12 0.34
53
-------
•9£ BUS
86ne6 ULEJ
-SA
ULBJ
'£2
OVERFLOW VOLUME (MG)
O
CO
-------
wastewater level measurements were obtained. Routine field main-
tenance was also simplified and expedited.
for easier data acquisition and
Relocation of the level sensor to better monitor the anticipated
flow conditions in the trunk sewers.
. Refinements to the characteristic flow equation for each overflow
site which allowed for more accurate flowrates.
•
or substantially minimized.
collection despite occasional telemetry problems.
OVERFLOW QUALITY CONSIDERATIONS
The basic purposes of the BMP overflow sampling program was four-fold:
To determine the extent and magnitude of the "first-flush" phenome-
na for each overflow site.
To determine the high-impacting overflow locations relative to the
total CSO pollutant loads.
gram.
55
-------
TABLE 17. SUMMARY OF RAINFALL AND COMBINED SEWER OVERFLOW VOLUMES FOR 1979
01
1979 Rainfall Characteristics*
Date
Jan 24-25
Feb 23
Mar 5
Mar 5
Mar 10
Mar 25
Mar 29-30
Mar 31
Apr 2
Apr 14
Apr 25
Apr 26-27
Apr 27
May 3
May 12
May 13
May 15
May 21
May 24
May 25
May 26
May 27
May 28
May 29
Jun 5
Jun 7
Jun 8
Jun 10
Jun 10-11
Jun 22
Jun 28
Jun 29
Jun 30
Jul 10
Jul 11
Jul 11
Jul 14
Jul 15
Jul 16
Jul 23
Jul 24
Jul 26
Jul 31
Depth
in.
0.73
0.18
0.11
0.21
0.11
0.13
0.37
0.09
0.53
0.19
0.18
0.19
0.29
0.12
0.61
0.06
0.11
0.24
0.63
0.26
0.39
0.07
0.11
0.44
0.10
0.34
0.07
0.14
0.31
0.15
0.35
0.12
0.23
0.26
0.12
0.13
0.41
0.68
0.09
0.23
0.12
0.27
0.70
Duration
hrs
18
6
3
9
5
3
6
2
12
2
2
7
9
11
1
. 4
1
4
6
4
6
3
2
5
4
2
1
1
4
4
9
3
3
4
1
1
3
2
2
1
1
6
4
!6Q**
in./hr
0.09
0.07
0.09
0.05
0.04
0.10
0.10
0.08
0.15
0.14
0.14
0.04
0.06
0.03
0.61
0.02
0.11
0.13
0.16
0.14
0.13
0.04
0.07
0.14
0.06
0.18
0.07
0.14
0.17
0.05
0.13
0.06
0.09
0.16
0.12
0.13
0.21
0.58
0.06
0.23
0.12
0.09
0.58
ikfflr
0.041
0.030
0.037
0 023
0.022
0.043
0.062
0.045
0.044
0.095
0.090
0 027
0.032
0.011
0.610
0 015
0.110
0.060
0 105
0 065
0 065
0.023
0.055
0.088
0.025
0.170
0.070
0.140
0.078
0.038
0.039
0.040
0.077
0.065
0.120
0 130
0.137
0.340
0.045
0.230
0.120
0.045
0.175
ADD;<
hrs
150
250
226
g
98
354
119
27
41
276
267
n
5
157
212
55
139
fifi
21
21
20
23
106
38
15
52
9
273
131
26
22
224
19
A
47
18
17
174
20
32
126
7
17.63
10.40
9.10
0.61
0.27
1.13
0
1.50
0.35
0.01
0.01
o
1.05
0.03
2.95
0
0.33
1.39
0.23
0
1.00
0
0.52
0
2.95
0.02
0.00
3.10
0.51
0.85
10
-
0
0.01
0
0.02
0.00
-
-
_
—
—
~
-
0.04
0
0
0
0
0
0
0
0.58
0
0
1.44
Overflow Volume. MG
11 21
12.00
1.00 0.00
4.21
1.75
21.00
0.46 0.00
0
0.04 0
-
-
•
-
-
-
~
"
1.67
2.72 1.13
0.93 0.29
0.00 0.00
1.57 1.42
0.00
0.00
0.00
0.07
3.94
0.00
0.00
1.46 0.09
3.01 0.78
2.25 2.08
Site Number
22
0.82
0.56
0.44
0.38
0.00
0.00
0.46
0
0.83
0.08
0.05
0
0
0
1.29
0
0
0.03
2.15
2.43
1.64
0
0
0.13
0
1.57
0
0
0.39
0.44
0.56
0.00
1.39
0.01
0.00
0.16
0.76
4.69
0.00
0.00
0.00
0.53
4.56
27 31
0 0.50
0 0.00
0 0.00
0 0.00
0 0.00
0 0.00
0.00
0.00
0.00
0.00 0.00
0.00
0.00
0.00 0.15
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.88
0
0
0
0
0.64
0
0
0
0.05 0.94
0 0.28
0 0.01
0 0.50
0 0.03
0 0.01
0 0.01
0 0.00
0.06 1.96
0 0.20
0 0.00
0.17 4.50
0 0.37
0.04 5.12
36
0.16
0.00
0.06
0
0
0.19
0
0.27
0.00
0
0
0
0
0.36
0
0
0.12
0.55
0.62
0.51
0
0
0.08
0
1.26
0
0
0
0.17
0.26
0.00
0.57
0.00
0.00
0.01
0.00
0.20
0.00
0.00
0.07
0.59
1.84
Total
18.95
23.12
9.54
0.44
0.61
1.27
6.00
1.75
23.62
0.89
0.06
0.00
0.20
0.00
2.70
0.00
0.03
0.15
2.70
3.05
3.03
0.00
0.00
0.21
0.00
6.42
1.67
0.00
0.72
6.88
2.55
0.01
6.45
0.04
0.53
0.18
0.83
14.38
0.22
0.00
10.83
5.79
16.74
(continued)
-------
_ •'••'*•
Depth
Date in.
Aug 4
Aug 10
Aug 14
Aug 26-27
Aug 29-30
Sep 2
Sep 6
Sep 10
Sep 13-14
Sep 18
Sep 28
Oct 3
Oct 5
Oct 8-9
Oct 20
Oct 23
Oct 27-28
Nov. 7
Nov 9-10
Nov 24
Nov 26
Nov 28
Dec 6
Dec 23
Dec 24-26
0.30
0.35
0.19
0.63
0.09
0.57
0.50
0.33
3.54
0.20
0.15
0.18
0^30
0.27
0.22
0.23
0.29
0.14
0.38
0.06
0.10
0.16
1.70
TABLE 17
1979 Rainfall Characteristics*
Duration Igo** ,laXB
hrs 1n°/hr In./nY
1
5
4
11
4
4
7
5
16
1
8
3
17
8
4
6
3
7
13
4
7
1
2
4
39
0.30
0.21
0.12
0.16
0.03
0.31
0.14
0.12
0.49
0.20
0.04
0.12
0.10
0.07
0.11
0.07
0.08
0.06
0.04
0.07
0.12
0.06
0.05
0.08
0.14
0.300
0.070
0.048
0.057
0.025
0.143
0.071
0.066
0.221
0.200
0.019
0.060
0.050
0.035
0.075
0.045
0.073
0.033
0.022
0.035
0.054
0.060
0.050
0.040
0.044
ADD)'
hrs
90
133
84
51
63
84
79
101
74
100
228
106
44
44
59
76
100
240
54
18
18
37
205
300±
24
(continued)
7
o.oo-
0.10
0.88
0
0
0
1.03
' 0
18.65
0
0
0
0.47
0.10
0
0
0
1.10
0
0
7.90
10
0
3.02
0.89
9.64
39.32
0.50
0.70
0.00
0.00
0.00
0.00
0.00
0.00
11
10.50
3.80
5.04
0.00
1.41
7.28
3.66
31.33
1.70
0.11
3.87
0.79
0.80
0.86
0.25
0.41
0.78
0.00
2.97
0.00
49.35
ZZZ^I^^^^—-— — •
Overflow Volume
, HG
Site Number
21 22 27
0.00
5.29
0.94
2.38
15.38
0.00
0.00
0.39
0.00
0.01
0.04
0.00
0.00
0.00
0.00
1.06
0.00
0.00
0.00
13.40
0.03
8.50
1.11
3.70
0.00
4.81
4.47
2.94
34.39
5.38
0.14
0.00
0.00
0.00
0.00
0.78
0.00
0.00
0.00
19.15
0
0.25
'o
0
0
0
0
0.16
0
0
0
31
0.00
3.94
0.60
0.87
0.00
0.21
0.35
0.03
0.59
0.17
0.00
0.42
8.86
7.41
1.37
1.96
0.00
1.80
5.60
0.98
18.78
0.22
0.49
1.31
69.19
_
36
0.00
3.06
0.39
0.49
0.00
0.64
0.75
0.11
0.08
0.01
0.00
0.00
0.00
0.61
0.00
0.00
0.00
5.47
Total
0.03
34.66
8.61
22.12
0.00
6.43
13.77
7.38
139.66
7.25
0.00
0.53
13.59
8.30
2.79
3.78
0.26
2.21
6.38
0.98
25.46
0.22
0.49
1.31
164.46
_-- — — — : •
measured at Monroe County Airport.
ttenslty (with respect to clock hour)
A^r^ty1^ 'defTd a^ ±^0^ separating identified storm events.
Total volume indeterminate due to excedence of flow meter measurement range.
-------
OF RAINFALL AND COMBINED SEWER OVERFLOW VOLUMES FOR 1980
CO
1980 Rainfall Characteristics*
Date
Jan 11
Jan 17
Mar 10
Mar 21-22
Mar 24
Mar 29
Mar 31
Apr 4
Apr 8-9
Apr 9
Apr 12
Apr 14-15
Apr 24
Apr 27
Apr 28
May 13
May 14
May 17-18
May 30
May 31
Jun 1
Jun 3
Jun 6-7
Jun 7-8
Jun 9
Jun 15
Jun 19-20
Jun 26
Jun 28
Jul 2
Jul 8
Jul 22
Jul 22
Jul 27
Jul 28-29
Aug 2
Aug 3
Aug 4
Aug 5-6
Aug 14-15
Depth Duration I60** lava*
in- hrs in./hr in./nr
0.38
0.06
0.38
1.20
0.18
0.23
0.29
0.25
0.12
0.13
0.18
0.23
0.09
0.13
0.99
0.33
0.06
0.48
0.09
0.47
0.40
0.10
2.12
2.17
0.08
0.15
0.71
0.28
0.46
0.19
0.09
0.58
0.45
0.16
0.10
0.13
0.60
0.72
0.60
1.24
11
2
6
18
6
9
12
5
4
1
9
4
1
2
11
9
4
9
3
2
4
3
4
4
1
5
9
3
3
2
2
2
8
3
2
4
8
1
6
2
0.09 0.035
0.05 0.030
0.24 0.063
0.11 0.067
0.06 0.030
0.05 0.026
0.05 0.024
0.10 0.050
0.03 0.030
0.13 0.130
0.05 0.020
0.07 0.058
0.09 0.090
0.08 0.065
0.21 0.090
0.08 0.034
0.03 0.015
0.12 0.053
0.07 0.030
0.25 0.235
0.32 0.100
0.05 0.033
1.97 0.530
1.05 0.543
0.08 0.080
0.07 0.030
0.24 0.080
0.20 0.093
0.25 0.096
0.16 0.095
0.07 0.044
0.45 0.290
0.20 0.056
0.11 0.053
0.09 0.050
0.06 0.033
0.17 0.075
0.72 0.720
0.26 0.100
0.71 0.620
* U.S. Weather Bureau data as measured at Monroe County
J60 " Mdx1«>un> hourly intensity (with respect to clock
'avg ~ Total "'"fall depth divided by storm duration
ADP?
hrs
120
48
64
70
46
101
25
89
110
16
58
38
236
. 69
8
347
15
82
297
20
28
27
88
24
32
18
122
155
38
86
144
329
4
121
25
84
4
51
4
1 198
Airport
hour) during
Overflow Vnlnmp Mr,**
Site Number
7
0.02
0.00
1.08
0.00
0.00
0.51
0.00
0.00
0.00
0.13
0.00
0.00
3.84
0.00
0.00
1.90
0.00
> 5.28 >
5.96
0.69
0.03
0.27
0.00
0.72
0.77
0.10
0.30
1.97
> 4.24
7.76
0.47
storm event
10
2.41
2. 00
1.96
0.17
0.00
0.00
0.15
0.54
0.02
0.19
1.92
1.12
0.00
0.68
0.00
0.08
0.94
0.25
5.99
2.08 >
0.60
5.29
0.47
1.14
2.14
1.22
0.14
1.74
0.50
0.22
0.23
0.68 >
0.06
11
0.09
0.00
9.60
1.77
1.57
1.15
0.00
0.19
0.00
0.33
2.60
0.14
0.41
21.71
0.45
0.00
4.96
0.00
7.79
8.62
0.08
6.50
20.14
7.11
2.43
0.40
5.09
0.11
0.00
1.06
0.00
0.38
0.00
0.00
10.00
8.75
15.94
0.00
21
0.00
0.00
2.56
0.00
0.00
0.00
0.00
0.41
0.00
0.00
0.00
0.18
0.00
0.00
2.70
0.01
0.00
0.45
0.00
1.35
I.b4
0.00
> 2.64
0.38
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.12
0.00
0.00
0.00
0.002
0.062
0.00
22
0.00
0.00
9.00
0.00
0.00
0.04
0.00
0.00
0.00
0.00
0.00
o.oo
7.93
0.00
0.00
0.69
0.00
1.10
0.98
0.00
> 5.45
> 4.94
0.00
0.00
0.00
0.00
0.01
0.00
0.00
0.44
0.00
0.00
0.00
0.00
1.05
> 1.61
0.23
0.28
27
0.00
2.74
0.00
0.00
0.15
0.00
0.00
0.00
0.00
0.00
0.00
5.41
0.00
0.00
0.41
0.00
1.39
1.81
0.00
3.29
3.26
1.25
O.CO
2.05
0.00
0.00
0.00
0.00
1.24
0.12
0.00
0.00
2.14
2.47
1.96
0.00
0.00
31
4.66
0.00
O.i)u
0.00
O.UO
0.00
0.05
0.00
0.20
0.00
0.00
o!o9
0.00
0.34
O.JO
O.bl
1.14
O.U13
1.35
1.70
0.68
O.J3
1.21
0.00
0.81
0.17
0.00
O.OO
0.00
0.00
0.00
0.00
> 0.60
> 0.68
> 1.46
> 0.39
36
O.UO
0.00
1.03
0.^5
0.00
O.UO
0.00
0.23
0.00
0.07
0.00
0.04
0.00
o.oo
1.95
0.03
0.00
0.55
0.00
1.19
1.29
0.00
3.45
4.71
O.bS
0.00
1.31
0.00
0.90
0.05
0.00
O.K2
0.55
0.00
0.00
0.00
1.44
2.72
1.99
0.01
Total
4.68
0.09
16.11
9.85
4.18
3.57
3.11
1.51
0.19
0.12
0.48
3.69
0.16
0.60
47.73
1.70
O.uO
8.08
O.UO
13.51
18.32
O.J4
> 33.95
> 43.17
10.31
O.o6
12.57
0.87
7.95
2.47
1.22
4.!>4
3.18
0.1,8
0.32
2.67
> 18.21
> 19.96
> 27.44
> 1.21
-------
call
ing from 90-min to the end of the overflow event.
-
- -• '"
c™m TahiP 19 a "first-flush", in which a disproportionately high pol-
i *• ?il^?,rarried in the first portion of the overflow, was generally
characteristics.
substantially reduced.
$,1 S1S1 S/l 1° '-" ISO" T!N tSmSd Sp^lSUl, 11 percent In
problems °I.d been Identified prior to both overflow rconitonng programs (6).
59
-------
cr>
o
— ...~_i- j..,. 1*1x01 i i_uon v,vni,c.mKrti JLUNJ DI UVtKrLUW bllh
Geometric Mean Concentration, mq/1
Drainage Area
7
10
11
21
22
27
31
36
7
10
11
21
22
27
31
36
Maplewood
Lexington
WSTS
Mill & Factory
Front
Seth Green
Carthage
Central
Maplewood
Lexington
WSTS
Mill & Factory
Front
Seth Green
Carthage
Central
30*
148
127
158
239
118
76
533
61
30
5.36
3.71
6.94
5.15
7.21
2.49
9.59
1.33
60
67
58
130
111
112
88
397
57
60
2.55
2.70
5.51
4.09
6.67
2.51
3.47
1.97
BOD,
0
90
36
55
69
30
79
70
410
45
TKN
90
2.24
1.32
3.14
2.60
7.59
2.80
7.03
2.76
TSS
> 90
32
34
58
67
429
43
;> 90
1.20
1.09
7.46
3.13
5.17
5.48
30
569
324
1043
760
553
454
1054
221
30
1.55
1.17
2.52
1.33
1.72
1.30
3.30
0.77
60
399
199
1200
432
473
438
977
223
TIP
60
1.34
0.68
2.81
1.12
1.38
1.18
1.84
0.97
90
210
238
710
550
401
364
829
161
90
0.67
0.61
1.62
0.49
1.40
1.11
1.S5
0.82
> 90
157
140
203
365
512
130
> 90
0.45
0.47
1.07
1.22
1.29
O.G8
Time interval ending at given minute.
-------
TABLE 20.
}UALITY DATA WITH 1979-1980 DATA
Rfcn Prnnrflm —
Drainage
Area
7 Maplewood
10 Lexington
11 WSTS
21 Mill & Factory
22 Front
27 Seth Green
31 Carthage
36 Central
No. Data
Points
126
93
13
21
15
282
23
Systemwide Mean Values
(incl. Site 31)
(excl. Site 31)
7 Maplewood
10 Lexington
11 WSTS
21 Mill & Factory
22 Front
27 Seth Green
31 Carthage
36 Central
135
103
22
21
15
286
23
Systemwide Mean Values
(incl. Site 31)
(excl. Site 31)
Arithmetic
Mean
. — - .. .——
134 ±
69 ±
130 ±
97 ±
136 ±
478 ±
61 ±
158
105
449 ±
129 ±
220 ±
474 ±
511 ±
591 ±
258 ±
376
340
28
18
32
33
94
49
22
80
15
46
280
370
65
71
Geometri c
Mean
— . — — —
BOD, mg/1
79
47
118
74
75
308
49
140
r r
ob
TSS, mg
247
111
200
306
269
438
212
280
201
(continued)
No. Data
Points
116
89
6
28
19
63
128
23
/I
116
89
6
28
19
63
128
23
BMP Program
Arithmetic
Mean
92 ±
94 ±
120 ±
163 ±
100 ±
77 ±
767 ±
51 ±
183
100
361 ±
261 ±
1000 ±
443 ±
486 +
377 ±
960 ±
184 ±
509
445
58
18
42
82
30
15
99
11
89
86
301
144
231
57
209
32
Geometric
Mean
-
50
59
113
82
83
57
482
46
102
57
190
165
961
318
298
293
637
172
290
216
-------
cr>
ro
Drainage N
Area
7 Maplewood
10 Lexington
11 WSTS
21 Mill & Factory
22 Front
10. Data
Points
184
157
24
22
27 Seth Green 14
31 Carthage 386
36 Central 34
Systemwide Mean Values
(incl. Site 31)
(excl. Site 31)
7 Maplewood
10 Lexington
11 WSTS
21 Mill & Factory
22 Front
27 Seth Green
31 Carthage
36 Central
Systemwide Mean Values
(incl. Site 31)
(excl. Site 31)
181
157
24
22
14
377
34
R&D Program
Aritnmetic
Mean
1
0
1
0
0
1
0
0
0
4.
3.
11.
1.
2.
7.
3.
5.
4.
.21
.26
.01
.21
.41
.76
.43
.76
.59
,41
70
07
86
60
63
96
03
60
± 0
± 0
± 0
± 0
± 0
± 0
± 0
± 0.
± 0.
± 4.
± 0.
± 0.
± 0.
± 0.
.48
.04
.24
.08
.28
.61
.13
60
65
10
81
57
80
73
f~\J V*"*-"
'
i i i nueu;
Geometric No. Data
Mean Pnint-c
0.35
0.16
0.25
0.30
0.33
0.33
6.92
1.33
2.40
4.98
3.38
4.42
3.10
TIP, mq/1
116
89
6
28
19
63
127
23
TKN, mq/1
116
88
6
28
19
63
127
23
BMP
. — .
Proaram
Arithmetic
rl
— — .I, _
1.21
0.95
2.33
1.01
1.43
1.22
2.32
0.78
1.41
1.28
3.91
5.71
5.26
3.98
7.67
3.04
12.35
3.54
5.61
4.65
can
± 0.56
± 0.26
± 0.58
± 0.25
± 0
± 0
± 0
± 0
.34
.31
.30
.12
± 0.85
± 1.42
± 1.89
± 1.77
± 0.
± 0.
± 2.
± 0.
59
48
33
89
Geometric
Mean
--
—
0.62
0.65
2.25
0.86
1.28
0.86
1.76
0.28
0.88
0.68
-""
2.27
2.38
4.93
2.41
7.57
2.54
6.69
2.58
3.33
2.56
(continued)
-------
CTl
co
Draih'age
Area
7 Maplewood
10 Lexington
11 WSTS
21 Mill & Factory
22 Front
27 Seth Green
31 Carthage
36 Central
R & D
No. Data
Points
139
99
15
21
15
255
23
Systemwide Mean Values
(incl. Site 31)
(ovrl SitP 31}
Program
Geometric
Mean
Fecal Colifprm
0.35
.0.15
0.14
0.25
0.77
0.54
0.12
0.35
0.24
• ••
BMP
No. Data
Points
(MPN/100 nil) x 106
116
89
6
28
18
63
128
23
Program
Geometric
Mean
0.24
0.16
0.21
0.31
1.40
0.35
0.37
0.16
0.28
0.25
-------
n*+ * ^unduma2°r °bservation is discernible from Table 20, which is asso-
™S ?™W1? Srth?2e overflow location (Site 31). Increases in BOD TSS
and TKN of more than 60 percent were observed from 975 to 1979-1980 One
large industry discharges a heavy organic loading into the Carthage Avenue
trunk sewer. In the last two to three years a continuing urban rlnewal pro-
ItnL^l "T1-601 1n an est1mated 30 to 40 percent removal of tributary
stormwater drainage to the Carthage Avenue trunk sewer. The loss of diluting
s?icsaaterCar?hLUpPhCted t0 be the.ma40r reaSOn why the overflow characer-9
istics at Carthage have risen so significantly.
If the overflow characteristics of the Carthage site are not included in
±iH°hPUtaHt10Yf Sf tem-w1de P°11utant concentrations, the average B^D
would be reduced to 105 mg/1 for 1975 data and 100 mg/1 for 1979-1980 data-
TSS wou d be reduced to 340 mg/1 for 1975 data and 445 mg/1 for 1979-1980 '
^
In general a dramatic change in drainage area characteristics (eUhersurl
face runoff or sewage) would be required to affect a significant change In
ntratrSi' ^ the V0}ums "**"* to^i^lute bacJeHa o
lower levels would be substantial.
1ttle
TABLE 21. SYSTEMWIDE MEAN POLLUTANT CONCENTRATIONS FOR 1975 AND 1979-1980
BMP SAMPLING PERIOD
Pollutant
BOD, mg/1
TSS, mg/1
TKN, mg/1
TIP, mg/1
Fecal Coliform
MPN/100 ml
Arithmetic
105
340
4.60
0.59
"
1975
Geometric
65
201
3.10
0.33
240,000
1979-1980
Arithmetic
100
445
4.65
1.28
-
Geometric
57
216
2.56
0.68
250,000
So 1Q7Q f^n H ? the r^atlvely good comparison of 1975 overflow quality
in T?P ! K^ ^H th?J °f the meanS for TIP' wherein a twofold in-
e in TIP was observed. The cause for the increased level of phosphorus
was not evident; however, it should be noted that the 1979-1980 TIP level
64
-------
approaches the 1.0 mg/1 standard for point-source discharges into the Great
Lakes drainage basins.
Several conclusions derived from analyzing the monitoring data are:
1 nrainaae area 31 (Carthage) had mean pollutant concentrations
l' ran fng from 48 to 355 percent higher than the overall drainage
basin mean concentrations, depending on the specific pollutant.
2 In general, Drainage areas 10 (Lexington) and 36 (Central) exhibi-
ted iSwer mean concentrations than did the remaining overflows.
3 Comparisons of individual drainage area pollutant characteristics
with the overall drainage basin mean concentrations indicated that
a 1 sites exhibited mean concentrations within 50 percent of the
Drainage basin mean for BOD, TSS and TIP, and within 65% for TKN.
Although the above analysis of CSO quality characteristics can be utili-
Vr e n-unVortTSting factor could be assigned to the oaramaters
to allow for the greater severity of particular pollutants.
As exhibited in Table 24, the WSTS overflow ranked as the highest
imnactina overflow followed by Front Street and Carthage. Maplewood,
XlSaton and Seth Green were of moderate impact (relative to the other
sites)! and Sill & Factory and Central were the least impacting of the over-
flow sites.
65
-------
TABLE 22.
cr>
CTl
POLLUTANT LOADINGS FOR A STORM OF 1.0 IN
— — — — — — : ...... ~.v,,», . u, j..u j,M, ur (uiftL rKtHKl IAI lUN
Discharge Area
7
10
11
21
22
27
31
36
Total
*
**
Maplewood
Lexington
WSTS
Mill & Factory
Front
Seth Green
Carthage
Central
FC = Fecal Coll form
Fiaurp<; in naronthac
Total
Discharge
Volume, MG BOD
2.44
2.25
7.50
1.03
2.37
1.98
1.01
1.64
20.22
expressed as
92
94
120
163
100
77
767
51
MPN/100 ml (ci
Average Pollutant
Concentrations, mq/1
TSS TkN TIP
361
261
1000
443
486
377
960
184
uncentrat
3.91
5.71
5.26
3.98
7.67
3.04
12.35
3.54
ion) and
1.21
0.95
2.33
1.01
1.43
1.22
2.32
0.78
MPN (loa
FC*
0.24x10^
0.16x10°
0.21x10°
0.31x10^
1.40x10°
0.35xlOX
0.37x10?
0.16x10
dlnq)
5
1870
1760
7510
1400
1980
1270
6460
700
22950
Pollutant
TSS
7350
4900
62550
3800
9610
6230
8090
2520
105050
Loadings
TKN
80
107
329
34
151
50
104
48
903
, IDS**
TIP
25
18
146
9
28
20
20
11
277
FC*
1.4x10?:?
e.oxio};
1.2x10}:?
12.6x10}:;
2.6x10,,
1.4x10}:;
1.0xl01J
28.3xl013
-------
en
TABLE 23. REGRESSION EQUATIONS BY OVERFLOW SITE CORRELATING OVERFLOW VOLUMESJQ.
h r Equation
Site
7
10
11
21
22
27
31
36
m
2.807
1.800
7.442
0.890
2.584
2.030
0.848
1.848
20.25
Total System OF
Total System OF
- 0.37
0.45
0.06
0.14
- 0.21
- 0.05
0.16
- 0.21
- 0.03
0.94
0.65
0.71
0.47
0.58
0.75
0.45
0.90
OF
OF
OF
OF
OF
OF
OF
OF
= 2.807 TR
= 1.800 TR
= 7.442 TR
= 0.890 TR
= 2.584 TR
= 2.030 TR
= 0.848 TR
= 1.848 TR
- 0.37
+ 0.45
+ 0.06
+ 0.14
- 0.21
- 0.05
+ 0.16
- 0.21
20.25 TR - 0.03 from summation of individual equations.
18.05 TR + 0.31 from regression analysis of Table 18.
-------
Figure 24. Rainfall - overflow regression equations by site,
68
-------
Drainage Area
High Impact Ranking (1 = highest)
BOD TSS TKN TIP FC
Ranking
7 Maplewood
10 Lexington
11 WSTS
21 Mill & Factory
22 Front
27 Seth Green
31 Carthage
36 Central
4
5
1
6
3
7
2
8
4
6
1
7
2
5
3
8
5
3
1
8
2
6
4
7
3
6
1
8
2
5
4
7
4
2
5
7
1
3
6
8
20
22
9
36
10
26
19
38
4
5
1
7
2
6
3
8
CTt
-------
SECTION 6
SOURCE CONTROL MANAGEMENT
CATCHBASIN/STREET SWEEPING EVALUATIONS
Background
At the heart of a BMP pollution abatement program are those source man
mSlaL b,PfnCtlthS WMch 3ddTS the rem°Val Of con'taminants wSere ?hej accu-
mulate before they are washed into the sewer collection system A source
control measure that has received considerable attention over the plst sever
nlif rVS^°re effective catchbasin cleaning and street sweepingP If
enilnna ,S rn^T™1^ '" a11 1and Surfaces *r* somehow ™ved before
entering a combined or storm sewer network, then they will not be discharged
to receiving waters through CSOs or stormwater outlets., aiscnargea
D KT^M* research? notab1y that conducted for the USEPA by the American
Public Works Association and the URS Research Company, has clearly reveled
Jithnanhr pollutlon P^ential of street surface contaminants (15 16J7?18)
Although more research is needed to establish the quantitative effect of sur-
^°c,taminantS,°n rTiVing Water
-------
TABLE 25. OBSERVED RUNOFF WATER QUALITY CONCENTRATIONS FOR
oMN OUOC. o.i
•
Numt
Parameter, Units* Ana
UU 1 \ J...
)er of
lyses
...
Common Parameters and Major Ions:
pH
Oxidation Reduction Potential, mV 39
Temperature, °C -4
Calcium r
Magnesium ^
Sodium r
Potassium ^
Bicarbonate 5
Carbonate ,.
Sulfate I
Chloride °
Solids:
Total Solids
Total Dissolved Solids
Suspended Solids
Volatile Suspended Solids
Turbidity, NTU**
Specific Conductance, umnos/cm
Oxygen and Oxygen Demanding Parameters
Dissolved Oxygen
Biochemical Oxygen (5-day)
Chemical Oxygen
•
Nutrients:
Kjeldahl Nitrogen
Nitrate
Orthophosphate
Total Organic Carbon
—
Heavy Metals:
Lead
Zinc
Copper
Chromi urn
Cadmium
Mercury
20
20
20
10
88
88
'll
13
13
13
5
13
5
• -
11
11
11
11
11
11
__ — . —
Minimum Maximum
• • —
6.0 7.6
40 150
14 17
2.8 19
1.4 6.2
< 0.002 0.04
1.5 3.5
< 1 150
< 0.001 0.005
6.3 27
3.9 18
110 450
22 376
15 845
5 200
4.8 130
20 660
5.4 13
17 30
53 520
2 25
0.3 1.5
0.2 18
19 290
0.10 1.5
0.06 0.55
0.01 0.09
0.005 0.04
< 0.002 0.006
< 0.0001 0.0006
—
Average
6.7
120
16
13
4.0
0.01
2.7
54
0.019
18
12
_.
310
150
240
38
49
160
— — "—
8.0
24
200
7
0.7
2.4
110
0.4
0.18
0.03
0.02
< 0.002
< 0.0001
• —
* mg/1 unless otherwise noted
** Neohelometric turbidity units
71
-------
°fCc?eanarb?mhaS sT01?" W CUrbed ^eets haJe T?eiatl ely ftgh degree
of cleanability. Streets with concrete gutters are more difficult to clean
shoulders •« S
The vehicle presently used the by the City of Rochester is the Elain A
;^
estimated capacity of the sweepers is about 3 cy. Material collect
15 ***** t0 * tronsfer Stati°n '1
City SMtT^^
presented'becau^ SJ ?J6 e?1st1"9 sewer.clea"^9 and maintenance program is
«r+?« because of its close association with catchbasin cleaninq This
section represents a brief summary of the effectiveness of sewe? flushing and
routine sewer maintenance on the reduction of property calls (comp aints)
All of the^work herein described is conducted by the Operations and Mainten
ance Division of the Monroe County Division of Pure Waters ?he preventive"
T"l97ni?hPSra!!JnCiUH1n9 S^er flUShin9 W3S establi^ed by the SlvlslSn
morp Utonc? 9 °^ ^ecreasin9 the number of house complaints through
more intensive sewer maintenance. The data as presented herein related to
operations conducted during 1977 and 1978. "eri1-ea nerein related to
During 1977, Pure Waters reported a very significant (23%) decrease in
trie!! T 6Th?I Lr°Per^ Ca11S Wltf?in the Gates-Chili-Ogden and Rochester Ds-
tricts. This was quite encouraging since the Division had increased their
service areas, areas of responsibility, and number of people served The^r
^th^A"-^1"9 the rber Of comP^a^ts appeared to be d rect?; re aied
to their highly organized preventive maintenance program. reiaiea
fi,,cMS 9 brief Ov?rv1cw' the Division of Pure Waters operates four hydro-
Thp nnn9'*VaCUUrn ° eaners' two hydro-fl ushers, three buckets, and one rodder
p nn* ,
^tions0" IhThvH^ ^ ^dr°-f1usher a^o provides the televised sewer
nspections The hydro-flushing, vacuum cleaner unit is capable of storing
11 cy of solid debris and holding 1500 gal of water. At current prices I new
72
-------
cleaner requires a two man crew.each ^ collected and the heavy
Sands placed the clE™^ anVflu^ng equipment preventative mainten-
ance on these units is essential.
,.
clean eight catchbasins per day.
The effectiveness of the 0DVeralltSewerbfelUs^^
IsLciatedwithconducting such a maintenance program are presented in
Table 27.
ram F ?fi. SUMMARY OF SFWER FLUSHING AND MAINTENANCE EFFECTIVENES^
Year
Description
Total Property Calls (Complaints) 12,046 5,805 4,413
Footage of Main Sewer Cleaned 635>°«3 152 169
Main Sewer Stoppages *** 3 8g6 3^595
Catchbasins Cleaned °>^-' 37'6Q3 43 087
Footage of Sewers Televised 44'^b 0/'
73
-------
JjBLE_27. COSTS ASSOCIATED WITH SEW^y^g/MAINTENANCE PROGRAM
MAIN SEWER " " ~ ~
Total Length Hydrocleaned 57 705 ic
Total Hours Charged-Hydrocleaning ?'?%*
Unit Cost-Hydrocleaning
-------
Figure 25.
General location map for catchbasin/streetsweeping
demonstration study.
75
-------
BERGEN STREET
-t
Control Area
xx f Control*.
x 4& Catchbasin1*
w
] „
"t\
]
OTIS
Street Slooe »
^^jf ^^\
' ^
»
Test Area
Long-term physical s*
inspection catchasin
«• 4t Na 3
^ 0
:
]
> I
I1
"*•••.« ^ to
FREELAND 2
tn
i-
"(M
•
'i t
i
CO
I f
Long-term physical
/ inspection catchbasin
/ No. 4
Control Area ^
STREET
3'-6" Brk
I- '•
UJ
UJ
o:
« C
-
1 c
o
^.Test ^^"^
Catchbasin ~i N
No 1 "^
Test Area
^ X
^ ^^
STREET
Figure 26. Schematic of catchbasin/streetsweeping demonstration site
representing a residential area.
76
-------
Figure 27.
Schematic of catchbasin/streetsweeping demonstration site
representing a commercial area.
77
-------
Figure 28. Residential test area.
Figure 29. Commercial test area.
78
-------
ThP evaluation program consisted of flow monitoring and sampling of the
catchbasins for evePra?9storm events under various street sweeping frequen-
catcnoasins ror ^ h evaluation plan that was followed. The plan
SS; tlat each test aria was to receive twice and eventually three times the
the routine sweeping as conducted by the
lABLt
Date
Apr 16
May 28
June 25
July 23
Aug 20
£O. HVMLUMI 1UI1 ri_rm
Week
1
2
3
4
5
6
1
2
3
4
1
2
3
4
1
2
3
4
1
2
3
4
Street Sweeping Frequency
Unaltered
n
n
ii
n
Increase 100% (double)
Increase 200% (triple)
Unaltered (original)
Increase 100% (double)
11
u
II
Flow monitoring from the catchbasins was accomplished by diverting curb
i
catchbas?n was easily computed. Sampling was conducted by collecting a grab
sample of the curb runoff flow at specified intervals.
Results
Results of three monitored storm events are summarized in Table 29.
Based on this information the following observations are presented:
Large variations in the actual pollutant concentrations occurred.
79
-------
TABLE 29.
00
o
— — : »• "• wn i ^iiun^xn nunx 1 UPvlHU UMIM DI O 1 UKN tVhNI
Storm
Land Use* Event No.
R
R
C
C
R
R
C
C
R
R
C
C
1
1
1
1
(5/21)
2
2
2
2
(6/28)
3
3
3
3
Rainfall
Volume-in.
0.25
0.25
0.25
0.25
0.35
0.35
0.35
0.35
0.26
0.26
0.26
0.26
Volume of
RunoffA
620
300
450
500
870
415
620
700
650
310
460
520
. Test or + Sweeping*
Control Area Frequency*
T
C
T
C
T
C
T
C
T
C
T
C
UNALT
UNALT
UNALT
UNALT
DOUBLED
UNALT
DOUBLED
UNALT
DOUBLED
UNALT
TRIPLED
UNALT
Quality Parameters4"1"
BOD
31
17
143
215
16
16
20
13
20
22
38
23
TSS
136
50
100
27
44
108
85
100
81
138
217
164
TKN
-•
0.1
1.0
2.9
4.2
0.1
0.1
0.3
0.3
N/A
N/A
N/A
N/A
Pb
0.53
0.34
0.13
0.08
0.06
0.13
0.30
0.29
0.08
0.26
0.87
0.70
• — -•"• .
*
A
Land Use - R = Residential, C = Commercial
Test/Control Area - T = Test CB, C = Control CB
Runoff Volume is in gallons (gal).
Quality Parameters are average values in mg/1.
Total number of samples = 64
Normal frequency: residential - once every sixth working day;
commercial - every day
-------
For Storm Event 1, the street sweeping frequency was the same for
both the test and control areas and similar pollutant concentra-
tions were expected. The fact that a large variation was observed
was lltel? a rlsult of other factors not accounted for, such as,
volume of traffic, number and location of parked vehicles, and
actual street sweeping efficiency.
Fnr Storm Events 2 and 3, the effect of increased street sweeping
was a Serai decrease in pollutant concentrations in the residen-
tial t«t area aslompared to the control area. The Impact .of in-
creased sweeping in the commercial area could not be determined
from these data.
Doubling of the street sweeping frequency in the residential area
resuHed in a noticeable decrease in runoff pollutant concentra-
tions whereas, the effect was much less pronounced for the com-
mercial area It should be noted that the normal street sweeping
frequency in the commercial area of once per day is very high.
The average pollutant concentrations were significantly higher in
the commercial area relative to those measured in the residential
area It was expected that surface loading rates would be higher
?n ?he ^ercial area because of the greater daily traffic volume
ThP averaae daily traffic (ADT) for the commercial area was about
2!oOO vehicles ; whereas, the ADT associated with the residential
area was approximately 550.
Based on these data, for normal street sweeping frequencies the
catchbasins contributed about 4.5 times as much. The 0.64 Ib BOD/
5n of rain appeared to be consistent with the value of 1.07 Ib ,
BOD based Snl3?51b BOD/curb mi. as indicated in an earlier report
nnratchbasin technology (20). The 0.64 Ib BOD/in. value also
Represented 'apprSat^y 60% of the pollutant initially on the
street surface.
Cost-Effectiveness
The BMP study tended to show that increasing the street sweeping f re-
whereas! the data for the residential area were inconclusive.
on results from a recent study on nonpoint pollution abatement
s s-a
81
-------
POROUS PAVEMENT DEMONSTRATION
General
Under
82
-------
SAN .10SE ANNUAL STREET CLEANING EFFORT (1976 - 1977)
CO
GO
Maintenance Supplies
Operation Supplies
Disposal
Equipment Depreciation
Cleaner Operations
Maintenance Personnel
Supervisors
Total Annual Costs
Total Annual Curb-
mi Cleaned
__^ —
— .. • ' •• -•
r.nsi
Cost
Total ($/curb-mi
Cost ($) cleaned)
93,000
29,000
65,000
31,000
326,000
176,000
80,000
$800,000
55,761 Miles
— , 1 — - — ' —
'•• —
1.60
0.48
1.17
0.48
5.76
3.20
1.44
$14.00
________ — — ' —
Percentage
of Total
Cost
12
3
8
3
41
23
10
100%
LABOR
Unit Labor Percentage
Total Labor (hr/curb-mi of Total
(person-days) cleaned) Cost
, — .
—
—
780
—
3400
1200
650
6030 Days
_ - ^ — ' — —
—
__.
0.12
— •"
0.50
0.18
0.10
0.90 Hrs
. — — — •
— _. — —
—
13
56
20
11
100%
—
"•-
Includes gutter and pick-up broom replacement.
Tires, fuel, and oil.
d These labor costs include administration, warehouse, secretary, and overhead costs,
a
b
c
-------
°ver
reci
over
porous
s? all
eme al
soils throughout the United States can meet all these requirements hybHd
systems have been developed to maximize the use of porous payment' to reduce
the lmpact of stormwater runoff. Thus, porous pavements ca'n be constructeS
th" falls onto the porous
On
into theaaroJnd"bJ°,,H?i5i|dr0l03lC "pect °f allow1"9 rainwater to infiltrate
men? mav aUn h. ^«f !ln ln9P°™us pavements, a significant degree of treat-
ment may also be realized. Combined sewer overflow as well as stormwator
contain substantial quantities of undesirable pollutants which may "removed
by porous pavements. The inherrent ability of the soil and pavement
e
runoff. Reductions in storm drainage construction costs, elimination of the
creasld'skid rP?^t9UtterS; ^d ^°^ traffl'c safet^ ^suiting f?l In
result (21 resistance and ^proved visibility on wet pavements can also
84
-------
Basis of Design
wMle Staining its highly permeable nature, was also evaluated.
flow reductions was promising.
Selection of Demonstration Site
locations are shown on Figure 30.
—
ward water movement.
85
-------
LAKE AVENUE
SITE
Figure 30. General location map for porous pavement demonstration sites.
86
-------
The SCO porous pavement test area consisted of two equal areas of pave-
ment, each 100 ft square and comprising 0.23 ac. The test area was con-
structed of 5 in. of porous asphaltic concrete over a base of crushed stone
approximately 9 in. deep. Under the stone base an impermeable asphaltic
membrane was applied to prevent collected rainfall stored in the stone base
from being transferred to the groundwater.
Under the configuration used in this demonstration, rainfall passed
through the porous pavement layers and was temporarily stored in the stone
base layer. Reduction in the rate of runoff was accomplished by allowing the
storage reservoir to be slowly drained by two 6 in. underdrains placed at the
bottom of the stone base. Flow in the underdrains was tributary to a meter-
ing pit where the rate of flow was determined by simple volumetric and weir
flow calculations.
The control area associated with the GCO test site consisted of a con-
ventionally paved area of equal dimensions but sloped uniformly towards the
center, where a standard stormwater inlet intercepted the surface runoff and
conveyed it to the same metering pit. Figure 31 shows the general layout of
the GCO porous pavement demonstration site. Figure 32 is a photograph of the
demonstration site.
The storage reservoir provided by the stone base at the GCO site was
sized based on completely storing a 5 yr - 24 hr rainfall for the Rochester
area. Technical Paper No. 40 of the U.S. Weather Bureau indicated that a
storm of this frequency would contain approximately 3.1 in. of rain. Assum-
ing that the crushed stone base had an inherrent void space of about 40%, a
stone base of nearly 8 in. was required. To allow for possible clogging of
the stones and to provide for more structural strength of the overall pave-
ment/base configuration due to superimposed traffic loads, 9 in. of stone
base was used.
At the Lake Avenue site, a porous pavement structure was placed directly
over a stone base without providing an asphaltic membrane beneath the storage
reservoir. One underdrain was installed and connected to an existing catch-
basin system. At this location rainfall that entered the porous pavement
either drained into the one underdrain or entered the groundwater by passing
through the soil immediately under the stone base. This type of drainage
system was felt to be sufficient to assess the applicability of porous pave-
ment^under the general conditions encountered in new residential areas or new
parking lots. The ability of the porous pavement to sustain rapid infiltra-
tion under traffic loadings was stressed at the Lake Avenue site. Figure 33
shows the general layout for the porous pavement site at Lake Avenue.
Several important observations were noted during the construction of the
porous pavement demonstration site. They included the following items which
should also be considered in future applications:
The temperature of the asphalt mix from the batch process to place-
ment and compaction is important. Heating of the aggregate to at
least 300°F, prior to adding the asphalt, insures that all moisture
within the aggregate will be driven off. Excessive moisture pre-
87
-------
z
UJ
UJ
>
g
to
D
0
K
2
UJ
o:
**
£ 1
h*
"0
0
«»
c
•D
w
*D
- C
(0
o
o
I
I
i o
a:
o>
D
O
CONVENTIONAL PAVEME
CONTROL AREA
ioo'
"o
0
£
o
1 «— 1
1
1
1
1
---ffl
-o
a
1 .1 t 1
S — £ c
£°- £5
(Ml
(3
Fiqure 31.
Schematic of porous pavement demonstration site
at the GCO treatment plant.
88
-------
Figure 32. GCO porous pavement demonstration site.
Figure 33. General layout of Lake Avenue porous pavement site.
89
-------
shou?/hpPH i H9 f asphalt t0 a99regate. The asphalt mix
should be delivered at a temperature of 225-2350F. A digital read-
out temperature gauge is useful for proper measurements.
One of the more critical factors in obtaining a structurally sound
but highly permeable pavement is proper compaction. Cool ng of ?he
?lnnSJ T fia1 and th? temPera^e of the mix during rolling are
important factors Rolling should not begin until the temperature
of the surface and mid-pack is about 170°F. A cooling rate of
approximately 60°F/hr appears adequate. Two passes with a steel
8-10 ton ro ler is sufficient. There exists a -
There exists a trade-off between
r^Muf?! ^^ and ^"erent permeability. Greater companion
results in stronger pavement at the expense of lower permeability.
An asphaltic membrane, if used, is much better applied in several
passes that overlap. This provides for a tight impermeable seal.
KV6r 3n+ imPermeable membrane should be accomplished by
^ base material onto the membrane such that the weight of
^equipment is carried by the base material and not by the mem-
*»i?rra°ci!!ffi1!!9 a" a?Pha1tic membrane, a smooth, uniform subbase
surface should be provided.
If the base material consists of stone, the maximum lift should be
a to 9 in. to protect an asphaltic membrane. This layer should be
thoroughly rolled to provide maximum compaction. It cannot be over
compacted.
Placing the open graded porous material on a wet asphaltic treated
porous material layer should be avoided to prevent rapid cooling of
the applied asphalt, which would result in aggregate binding and
decreased permeability.
Additional rolling with a light roller can be made to remove any
small ridges in the pavement created during the compaction with
the heavy roller.
Monitoring Program
Hydrologic Testing—
The results of the hydrologic testing of porous pavement at the GCO
demonstration site indicated that the type of porous pavement system utili-
zing an impermeable membrane and underdrains could substantially reduce the
peak runoff rate relative to that from a conventionally paved area with
stormwater inlets. A monitoring program was conducted from September, 1979
through August, 1980. Winter months were not included because of snow and
ice buildup in the metering pit where flow measurements were taken. Compari-
sons were made as to the rainfall recorded by the local rain gauge at the
90
-------
demonstration site and that recorded by the U.S. Weather Bureau located only
a short distance to the east.
Tables 31 and 32 present the monitored rain and flow data for 1979 and
was generally similar, but large variations can occur.
Tables 31 and 32 indicate that the peak runoff rate from the
TCS t K cUed™1thfthe conventional pavement because of the rapid sur-
face runoff and the minimal travel distances involved.
0.06
0.05
0.04
0.03
O.02
0.01 •
Poroul Pavement
Oulfoll Hvdrograph
7:OO SCO 9OO
1000 11:00 12:00 raw) w:oo 15:00 ie:oo nroo isoo 19:00 20:00 a:oo 2200
TIME
Figure 34. Runoff hydrographs for 4/28/80 storm event.
91
-------
Date
9/02
9/03
9/04
9/05
9/06
9/10
9/14
9/18
9/28
10/03
10/05
10/06
10/07
10/08
10/09
10/10
10/12
10/13
10/14
10/17
10/20
10/23
10/24
CB
0.41
0.02
0.01
0.02
0.02
0.02
2.50*
0.21
T
0.08
0.063
T
T
T
0.036
T
T
T
T
T
0.086
0.008
T
Peak Q -
PP/CB
0.11
0
0
0
0.50
0
*
0.07
0
0.05
0.38
0
0
0
0.03
0
0
0
0
0
0
0
0
* Flowrate exceeded
A Local rain qauqe m
cfs
PP
0.044
T
T
T
0.01
T
5.08
0.015
T
0.004
0.024
T
T
T
0.009
T
T
T
T
T
T
T
T
maximum reading
alfunctionpri fm
Total
WB
0.57
0
0
0
0.50
0.33
3.54
0.21
0.15
0.18
0.84
0.03
0.02
0.09
0.22
0.02
0.21
0.03
0.05
0.07
0.30
0.29
0.01
11 1 un i n DrtOC
Rainfal
- In.
GCO
0.69
0.06
0.02
0.05
0.48
0.33
N/A A
1
Peak -
WB
0.31
0
0
0
0.14
0.12
0.49
0.20
0.04
0.12
0.10
0.01
0.02
0.04
0.07
0.02
0.04
0.03
0.03
0.06
0.11
0.07
0.01
In./Hr
GCO
3.00
3.00
0.01
2.55
0.11
0.32
• N/A A
of monitoring device
" 1"hncci n*i\/an c-fr\vimc- fm^t-n n 1 i n -i. : ._
v v — - — — - — .. — ••» i v i wiiw«*^» H ' * ^ I | Jl
1979. Unit repaired by 11/79.
CB = Catchbasin Control Area
PP = Porous Pavement Test Area
WB = U.S. Weather Bureau at the Monroe County Airport
GCO = Gates-Chile-Ogden STP
92
-------
TABLE ot. lytsu ruKuuo rnvc.nc.rn umn un^u. ., _ —
Peak Q, cfs
Date
5/13
5/17-18
5/31
6/1
6/6
6/7-8
6/15
6/19-20
6/26
6/28
7/2
7/5
7/15
7/17
7/20
7/22
7/27
7/29
8/2
8/5-6
8/15
CB
.0089
.14
.497
.88
.497
.497
.0046
.203
.226
.102
.088
-0-
.07
.497
.003
.497
.226
.041
.280
.497
.242
.497
PP/CB
0.054
0.64
0.80
0.45
0.13
0.14
0.27
-0-
0.36
-0-
0.76
-0-
0.11
-0-
0.82
0.50
PP
.0048
.09
.40
.40
.497
.0006
.028
.061
-0-
.032
.12
-0-
.38
-0-
.497
.025
-0-
.23
.497
.12
.95
WB Rain Data
Total
in.
.31
.48
.47
.40
2.12
2.16
.15
.71
.28
.48
.19
.04
.07
.10
.06
1.02
.16
.02
.13
.72
.60
1.24
Peak
in./hr
.08
.12
.25
.32
1.97
1.05
.07
.24
.20
.25
.16
.02
.07
.07
.03
.45
.11
.01
.06
.72
.26
.71
GCO Rain Data
Total
in.
.37
.59
.41
.49
1.92
2.46
.15
0.99
.30
.53
.20
.07
.11
.40
.07
1.00
.25
.09
.21
.56
.60
.89
Peak
in./hr
.30
.24
1.60
1.08
3.00
6.60
1.20
4.50
1.20
0.60
0.60
0.60
.40
1.54
1.20
1.39
1.28
0.96
2.60
2.80
2.20
1.48
rdrr^'^oJate'nnh1 xr %
ment test area Flow occurred at a much lower rate but continued over a
longer perioTof t!« relative to the hydrograph for the control area.
the porous pavement structure.
Granular material was stored immediately off the pavement area. During^
heavy rainfall washout of this material onto portions of the porous pavement
93
-------
occurred. This material was largely responsible for partial clogging of the
porous pavement. Protection from erosion of adjacent ground surfaces should
be provided to maintain porous pavement permeability. Field observations n-
dicated that material carried onto the pavement from vehicular "Iff 1c waV
not a major contributor to clogging problems. trarnc was
Structural Integrity—
rrn £S^S 1?^9t ^f fi°uWas "9* allowed on the P°rous Pavement area at the
GCO demonstration site. Heavy infrequent truck traffic was allowed on the
test area during most of 1980. No observable structural degradation of the
porous pavement was noted. In addition, no problems resulting from actual
freeze-thaw conditions were observed.
al J° .?eneral1y observed that snow and ice did not accumulate for
f time T ^e P°rOUS Pavement relative to the conventional pave
ng ' '
over tus^
structural degradation was observed.
Permeability Testing—
torhn^eVl°-S^peiTe^bl!ity testin9 of P^ous pavement using simplified field
techniques indicated that pavement infiltration rates as high as 1000 in /hr
can be achieved (21) Jo more accurately define the actual inflow potent a"
SntFTSVrTT.*'.,4 I"' dl'a!fter °0reS °f the pavement were Obta1ned from
both the GCO and Lake Avenue demonstration sites. Laboratory permeability
testing was conducted during 1979 which indicated that the inflow rate varied
from 1980 in./ hr at the GCO site to 170 in./hr and 43 in./hr at the Lake
Avenue site. The two values associated with the Lake Avenue site represented
test results for cores obtained from clean and dirty areas, respectively
The clean area represented that portion of the test pavement that received
little or no traffic; whereas, the dirty area represented a portion that re-
ontoetheeSavement ing and a heavy aPP1icati°n of soil particles washed
Permeability testing conducted during 1980 indicated that the inflow
potential for all three areas remained high, although noticeably reduced from
rrn l"l J f?5 *. values. These test results ranged from 540 in./hr for the
bCO site to 160 in./hr and 27 in./hr for the Lake Avenue site.
To determine the effect of abrasives added to roadway surfaces during
the winter months on the inherent permeability of porous pavements, a simple
test procedure was established. The testing consisted of the addition of a
predetermined volume of beach sand to a pavement test core after which a
falling head permeability test was performed. According to a report publish-
ed in 1976 approximately 1.0 Ib abrasives/yd2/appli cation are used by most
highway departments for deicing purposes (23). The test procedure attempted
to approximate actual application rates, the effect of vehicle loading, and
94
-------
sr
.
structural integrity was also conducted.
The basic equation used in determining permeability was as follows (24):
K = aL. In ho_
At h1
where K = permeability coefficient - in./hr ^
a = x-sectional area of standpipe_- in
A = x-sectional area of sample - in.^
L = length of sample - in.
h ,h = oHginaVand final hydraulic heads, respectively - in.
In the tests conducted, the areas of the sample and of the standpipe were
identical; therefore, the equation was reduced to:
K = L_ In ho
t h1
That is, the permeability rate is directly related ^the^en^of.the^test
ratioPof initial and final hydraulic heads.
\ ?n 3 of sand were applied and permeability tests were conducted after each
Lch'aoDlication Figure 35 presents the effect of sand addition on the
permeabi tfra?e. Amarked decrease in the K value with initial applica-
tiSns of sand and a rapid leveling off after successive loadings was ob-
served It is important to note that even after six such applications, the
Dermeabil ty rate of 27 in./hr still represented a very high rate Rainfall
intensit es of this magnitude are never encountered in the Rochester area.
Instantaneous pSk intensities may approach this value but their occurrence
would be very rare.
95
-------
560
1 2 3 4 5 6
SAND APPLIED - in.3
- Figure 35. Porous pavement permeability testing with sand addition.
Soils Suitability for Porous Pavement
All pavements require support from the subgrade to prevent excessive
pavement deformation and break-up. The subgrade generally does not have
adequate support and resistance to water and frost; therefore, a more ad-
equate base is required between the pavement and soil subgrade.
The following factors, relatins to the subgrade, should be considered in
the design of porous pavements:
Supporting capability of the soil subgrade
Water storage capacity
Frost penetration
4... ,J??Joad bear1n9 capacity of the soil subgrade is generally measured by
the California Bearing Ratio (CBR) technique. This technique consists of
measuring the load required to drive a piston of a standard size into a soil
sample at a given rate. The CBR is the load in lb/in.2 required to drive the
piston a distance of 0.1 in. or 0.2 in. and is expressed as a percentage of
the load required to drive the same piston an equal distance into a standard
sample of crushed stone.
The water storage capacity of porous pavement depends on the soil's
capacity to allow infiltration of water. Subgrades with low infiltration
rates (0.01 ft/day) require greater base depths to allow rainfall to infil-
96
-------
provide ThiSer storage capacity and infiltration rate.
resistant.
Soil Type Favorable for Porous Pavement—
The ideal soil subgrade for porous pavement applications would have the
following characteristics:
Adequate load-bearing capacity when both wet and dry
Well -drained
High permeability
High porosity
t S r-rJS
J^^^
Soils of Male ay'content are unacceptable, since the low porosity severely
lim Us inf Itration and the soils may absorb more water than necessary to
f T the vo ds The latter situation results in swelling and a corresponding
decrease in load bearing capacity. In certain situations, a clayey soil may
be Seated by adding cement or lime resulting in a more porous mass.
Monroe County Soils—
As stated above, a sandy silt soil above the water table with a permea-
bility- greater fhan 6.01 in./hr is ideal for porous pavemer it ^ades- ™e
cnii* in Monroe Countv are highly variable and include glacial till, shale,
aSd imestone TheWsS Is generally have highly adequate infiltration rates
to Vl S£ their use as subgrade materials for porous pavements. In Monroe
Countv ?he seasonal high water table is generally 0-2 ft below .the surface
(25) The water^abl^could at times severely limit infiltration through
porous pavements into the subgrade, thereby resulting in surface ponding.
ThP maximum freezing depth below the surface is also important for pro-
ner operation of porous paveLnts. Frost heaving and ultimate cracking of
the Savement may Sccur if adequate considerations are not given to this
Engineering projects generally allow for a maximum freezing
97
-------
SBtSS ^^are l«J±! 3T»i, STW"
The pavement and^base would lay above the subgrade. Assuming that 5 in of
Dfil^OMQ r\i% worn on T**ioiit*rt^4 -» u»«• 14. o ,c-i_ f i • *^ **• • ** w «./ 111 • vji
Huruub pavement is used, about 3 ft of base would be required tc
freeze-thaw damage to the pavement. H""eu u
A review of soils found in Monroe County indicated that there are arpas
amlVhpr P°rous P;vement applications, ^inal deLnS?nat on of favorab e
n H K - evaluated on a site-specific basis. Important parameters that
should be investigated include: soil permeability, particle size distribu
ean"9 caPac1t*» dePth to ^ater table, anPd maximum dep?h oTfrost
INLET CONTROL CONCEPTS
General
Over the years, surcharged storm and combined sewer systems and surface
thp P^rfhaV%CaUSed C0nstderab1e P^Perty damage. In an effort To a legate
the effects of excessive runoff, alternative solutions have been implemented
LVP ?L;n?itaH°eS- Iradnionally> 'areas frequently subjected to flSo™
5^ ?nstallfd n^w stormwater relief sewers to convey more of the runoff away
^^LfJ 2!*!: "*?• Jhe installation of backwater valves and the *
also he]Ped to allevlte th
th«P nn n °f remedial action taken' 1n ma"y aas,
these flood-proofing" measures have only caused problems to occur elsewhere
in the drainage basin. New relief sewers normally are very expensive both
in terms of construction and disruption to existing neighborhoods.
Many large urban centers have initiated costly structurally-intensive
spwerovP^n^H^ t0 S?1Ve Pollution P™bl^s resulting from combined
sewer overflow and stormwater discharges to receiving water bodies. Many of
these programs are also intended to relieve the individual homeowner of base-
SLf k-"P'.and widespread surface flooding. A less costly and positive
partia solution to certain drainage relief problems has recently been intro-
duced in the United States and should be considered as an alternative sol u-
-
« uJpTJh10 drainage Problems (26). The basic concept of inlet control
falls under the general category of Best Management Practices.
By necessity, any sewer conveyance system does not have sufficient
Slnfim pLn?cVeyTa11 of ^he stormwater runoff resulting from all possible
rainfall events. Jo provide for every possible event would not only be pro-
hibitively expensive but, in many instances, would result in moving pollution
or flooding problems downstream potentially inducing more serious damage
The past policy of removing stormwater runoff as quickly. as possible has're-
whi?p 'H f ag-H-° s^ures downstream as well as to the environment as a
whole. By providing inlet control such that the rate of stormwater inflow
sSch « ha^pnt h6 "P801^,^8^18*1"9 collectl'on system, many problems
such as basement back-ups, shock pollutant loadings to treatment facilities
resulting from the first-flush phenomenon and pollution from CSO discharges
can be minimized or eliminated. However, stormwater inlet control will re-
sult in a greater level of surface flooding. In most instances, however
98
-------
ater temporarily detained in the streets will result in only minor pro-
bof ^convenience; whereas, stormwater allowed to enter the sewer system
at uncontrolled rates can result in significant damage from sewer surcharge
and downstream flooding.
One
of inlet control method recently introduced into the United
^^
the HySro-Brake nvcZes a swirl pattern action which Dissipates energy to
control the rate of discharge. Figure 36 presents a schematic of a Hydro-
Brake regulator.
INFLOW
DISCHARGE
Figure 36. Schematic of a Hydro-Brake regulator.
99
-------
Santee Hydro-Brake Demonstration Program Description
The concept of inlet control to reduce downstream sewer system
« beins demonstrated in th
The demonstration study area is located on the west side of the city and
comprises 35 acres of primarily single family residential houses. The entire
area is served by a combined sewer system which is tributary to the West Side
Ilthln 5KrHrJherS arS ab°Ut 252 h^S6S and 8 c<»cial establishments
rn2- H Damage area, many of which have roof leader connections to the
combined sewer system. Sixty-two catchbasins within the area are present v
systera- A sctaatic °f
trolled release from the tank by a Hydro-Brake regulator was to be demon-
strated. Secondly, the concept of utilizing more surface/street ponding of
e e'Sa'Ld ^ ^ 1nfl°W t0 a".ex1sti"9 combined sewer system was to
be evaluated. Each option, or a combination of the two, offered a viable
methodology to reduce the rate of inflow into the sewer system through use
of flow restrictors. Such flow restrictors or regulators could be Hydro-
SnW^-f orifices *> throttle runoff inflow. One advantage of the
Hydro-Brake unit over an orifice was that the head-discharge relationship
cou Id be specified and controlled with a Hydro-Brake such that discharge
device essentially independent of hydraulic head conditions acting on the
anal Jo! ^ S°m|?1eted^to date Deluded necessary field surveys, complaint
analyses, the design and construction of an off-line storage facility and in
stallation of required monitoring equipment.
A field survey was conducted to acquire the necessary input data for
subsequent system hydraulic modeling. Information, such as sewer sizes
slopes and manhole inverts, catchbasin numbers and locations, and extent of
house roof drain connections to the sewer system, was obtained during field
I nbpGGT. I OiiS •
A complaint analysis was conducted to identify flooding problems within
the study area. Information was obtained through distribution of a home-
owners survey, as shown in Figure 38, and review of previous complaint re-
cords filed wnh Monroe County. About 25 percent of the total number of
surveys (241), which were hand distributed to homeowners in the study area
were returned. Table 33 presents the street location, number of responses]
and the number of responses which indicated basement flooding problems.
100
-------
„ * r
*r
t
\>
i>
-^-!
is NWNHON j
Z
1 — — -
cffc
• 1
"1
-,
.1
IS XttBAV
1
(
^
*
IS NQJ.H9IWN 'OW
IS 3TI3SVSI
i
UJ
3 •
-------
FLOODING SURVEY
1) Does your basement flood during rains?
D Yes n No
2) Have you previously filed a complaint?
D Yes Q No
3} How many times per year does basement flooding occur?
4) How does your basement flooding frequency compare with some of your
neighbors?
D about the same n more than
D less than
5) Is Street flooding a problem in your area?
Q Yes n No
6} Does basement flooding always occur along with Street floodinq?
O Yes D No
7) Does Street flooding ever encroach on your property?
P Yes D No
8) Has your street ever been closed due to floodinq?
a Yes a No
9) In your opinion, what location in your immediate area experiences the
worst basement and/or street flooding.
10) Comments:
Owner's Name:
(address if different)
Date:
Building Address:
Reach: (Office Use Only)
MH to MH
Figure 38. Homeowner's survey questionnaire.
102
-------
TflRIF 33. SANTEE HOMEOWNER SURVEY RESULTS*
No. of Responses No. of Responses
street Received w/ Basement Flooding
Michigan \* 2
Curtis {5 3
Emerson 1^ 0
Kestrel 6 0
Curlew ji 0
Santee b
* Based on a 25% survey response
have had on basement flooding.
Off-Line Storage Facilities--
The purpose of the off-line storage tank with Hydro-Brake regulated out-
flows S?ter stormwater runoffhad entered the collection system.
installed at the tank outlet.
Figure 40 presents an overall plan and profile of the off-line storage
facility.
Installation of Monitoring Equipment—
Tn arruratelv define the areas of surface flooding and sections of
103
-------
CS«3
H
kJI/*l-ll/* Akl '
D- — I
C8*2^
aca
N
Existing Catch Basins
.Proposed Piping Between
Catch Basins and Off-
Line Storage Tank
Proposed Flow
Monitoring Location
VILLA STREET
STREET
b3'5
BAUER STREET
Fence
Proposed Off-Line Storoge Tank
Valve Manhole
RILEY PARK
Note: For drainage area
tributary to tank,
see Figure 37.
Scale:
50'
Figure 39. Schematic of off-line storage facilities associated with
Santee area Hydro-Brake demonstration site.
104
-------
99'
^S
t.
119^1
•IS.J.
•1,9=1
e
'x
W
0
j.
%sro-,Q2 <
Z S3 l
%39'0 -,82
%9Z'0 -02
f 80
JO'II9 = 1 \ T S HJ
UJ
ifr OIS =1
o c
5i2
Fiaure 40. Plan and profile of off-line storage tank
for the Santee Hydro-Brake demonstration.
105
-------
,HP ^L PH -°?WaJe!; mod^?!?9 °f the sewer system within the Santee drain-
anrpH £L !? ??* P,r°bab 6 S6Wer Surchar9ing along Emerson Street, toni-
tored data collected to date indicated that several sewer sections along this
street experience frequent surcharging. Additional modeling studies we?e
rprpiv! SV^T6 the"umber and location of the catchbasins that will
receive a Hydro-Brake regulator to restrict the rate of stormwater inflow
during rainfall. The results indicated that 13 Hydro-Brakes are needed
studvLSrS ?rsi1f9 deV1'CeS Were 1nstal1ed at several locations within the
proiec? ThP ? ™WmnCTa-e T^™9 of flows throughout the demonstration
Figure 41. monitoring locations are listed below and illustrated in
1. Emerson & Robin
2. Curtis & Santee
3. Curtis - 1 MH west of Santee
4. Michigan - 1 MH west of Santee
5. Villa & Santee
6. Storage Tank - MH at north end
The monitoring data were used to develop and evaluate system hydrographs.
Flow Monitoring Data—
Flow depth data were collected and reduced for the following sites:
1. Emerson & Robin
2. Curtis Street
3. Michigan Street
4. Santee & Villa
Pl°tS W6re const™cteci are presented in
Date
5-18-80
6-06-80
6-07-80
7-22-80
Total Rain*
in.
0.40
2.19
2.17
1.03
\i-\^ni rn-i. rr\t\rtr1d 1 C.KJ
Max. Hourly Intensity*
in.
0.12/hr
1.97/hr
1.05/hr
0.45/hr
Note: Rainfall parameters were taken from records at the
National Weather Service Office at the Monroe County
Airport. J
106
-------
ii
NHM3WJ
"IS
i
l->
en
(\
f-
i
itU O
j
K
s
te
\
!»
i
;
i
-*
Vis xi a
\
y ^^_^
\^^
IS NVWdON I <^ j
Figure 41. Flow monitoring locations within Santee area
Hydro-Brake demonstration site.
107
-------
Monitored data collected to date indicated that frequent surcharging of
the sewer system occurred at various locations within the Santee drainage
.I6 \ TM- 42 indicates that sewer surcharging is a problem at Season
Street and Michigan Street. Figure 42 shows that the 12-in pie on S
. Pipe Cr0wn durin9 the str on 5-18
6 7 80 om PVP 5 THnJ? the 6'6"80 event» ™* almost four feet during the
6-7-80 storm event. The flowrates under these surcharge conditions were un-
known, but in any case, the flows had to be significantly greater than the
t^ <* other9monnoring da?a
9enerally
1.00 in. As would be expected, the peak flow rates generally increased with
an increase in rainfall intensity. The Curtis Street and Santee and VII Ta
pr'ogr'am™9 10Catl°ns dld not experience any surcharging during the monitoHng
Remaining Activities--
The monitoring program was suspended in October, 1980 and will be rein-
stituted in April, 1981. Once the Hydro-Brakes are nstalled, work will cSn-
tinue towards evaluating the effectiveness of the total inlet con troT pro-
gram. A final report detailing the findings will be completed by July, 1981.
OTHER SOURCE CONTROL MEASURES
Land Use/Zoning Restrictions
sianifnt + deve1°Ped ^™ugh zoning ordinances, can
significantly affect both the quantity and quality of combined sewer over-
flows. Zoning ordinances are usually based on the community's concept of the
best use(0f land. Development of an area generally leads to an increase in
v^c^f,?/ e1atlve imperviousness. Since increases in imperviousness ad-
versely alter runoff and overflow characteristics, zoning which limits
development is beneficial from the aspect of stormwater management. However
changes in zoning which promote open spaces or less impervious areas (e a
rezoning commercial land to residential) often devaluate the price of land
'
«» Planni"9 boards and reviewing agencies may establish codes benefiting
overflow reduction. Restrictive ordinances which eliminate direct entry of
sump pumps and roof drains into the sewer system have the same effect as re-
ducing the imperviousness in a drainage area because total runoff and peak
runoff entering the sewer system is necessarily reduced or attenuated.
specifying the use of porous pavement in those areas with suitable subsoil
conditions is another method also having the effect of decreasing imperviou-
sness. Planned open space within developed areas which can be used for both
108
-------
PIPE
SURCHARGED
UNKNOWN
AMOUNT
0000 0.00 0200 0300 0400 OSOO 0600 070O 0800 0900
TIME IN MRS
IOOO 1100
Fiaure 42. Combined sewage flow depths at Emerson
and Robin for selected storms.
109
-------
30
10
oooo oioo oaoo 0300 0400 osoo oeoo o?oo oaoo osoo
TIME IN MRS
Figure 43. Combined sewage flow depths on
Michigan Street for selected storms.
110
-------
recreation and surface retention is multifunctional and maximizes land
use.
an nntinn available to planning boards and reviewing agencies is to re-
1? guidelines ?or attaining relative imperviousness values.
Erosion Controls
careful clearing and grading during dry seasons.
SCS also provides technical on-site assistance upon request.
sites.
Surface Retention
facilities.
Monroe County has such an ordinance.
Ill
-------
«™ H \ e SUCh ordlnances have been adopted, the regulations have
served to encourage preservation of open space and utilization of natural
drainage concepts, including swales, small detention ponds and rainfall de-
tention on low use open areas (such as playgrounds, parks and parking lots).
In the more intensively developed areas of the City of Rochester there
!!n,,«TU3 lncomPati^;ities with many of these techniques. High llnd
values tend to prevent the preservation of much open space and the demands of
heavy pedestrian traffic prevent intentional temporary ponding in areas that
might otherwise be suitable. However, a number of more special zed tech -
?S,J?Vrnn??n dT10P6d fy intenS6ly devel°Ped areas/sSch as use of in-
tentional rooftop storage and porous pavement.
Buildings with flat-sloped rooftops are used in some places for storm-
water detention. Because of rooftop elevations storage caS be provided that
is not inconvenient for pedestrians or motorists, that is not unsightly and
that does not pose a hazard to children. Rooftop storage is not prob em-
free, however, as there are possible problems from leakage, structural Sver-
' '
Storing the five year storm on roof tops would amount to an increased
an b/ft T' at a dePth of i'73 I"- which is well below he
40 Z
' - w e
design loads in this region. Thus structural considerations should
iany f° dlfferential relative to conventional building practices.
anp H°5fin? matrials are 9ene™Hy not designed to withstand leak-
?™0™ K?°UndeK Water; h°wever' new roofin9 systems incorporating continuous
impermeable membranes are now being marketed at costs competitive with con-
ventional products Past experience in other locales has indited that the
cost differential between a detention roof and a conventional roof would not
^significant if incorporated in new construction or major rehabilitation
The most extensive use of this concept has occurred in the 300 acre
an 6Wa ?° 1n downtown Denver (28). Since its initiation
n n thn n . on
tn if «' th?,Denrr Urban Renfwa1 Authority has required private developers
to temporarily store (on-site) stormwaters directly falling on their proper-
ties. In general this requirement is met through the use of rooftop pondinq
ponding in plazas and ponding on open grassed areas. The Director JfP°naing'
Engineering for the Renewal Authority reports that costs have not proved a
problem to developers and that the city's experience with on-site detention
SanPw^nAMth^-ta"°rablei(28)\ PreParations *™ now being made to extend the
Renewal Authority's development requirments to other areas of the city.
Drtr.u Op.en arcas ^d Park,land comprise about 20% of the total surface area in
Rochester . Flooding park land and open spaces appears to be more feasible
than rooftop storage with respect to total runoff capture, but the disadvan-
tage to flooding is post storm grit and debris clean-up. Because of addi-
tional operation and maintenance costs, flooding parkland does not appear to
be institutionally feasible. Storage ponds are required for depression
storage and therefore this application is significantly limited in developed
112
-------
areas Surface storage in the urban areas of Rochester would be difficult
tolmplement and therefore is not considered practical.
COST AND BENEFIT CONSIDERATIONS OF SOURCE CONTROL MEASURES
pSveS to decrease imperviousness and reduce stomwater runoff.
from CSO and stormwater discharges are:
Sewer cleaning and flushing
Catchbasin cleaning
Porous pavement
Inlet control measures
Erosion control practices.
=£
occurring to the receiving waters.
-•a ~:»
posits as determined from field inspections.
113
-------
surface storage or flooding is acceptable. This is precisely the u^nn
Given the approximate equal costs for conventional asphaltic
^
"' the
ties sucfar?^ S?s* a™*6 fr351:0",00"""01 measures suggested by authori-
*!„ ij i u ' e "s^y implemented at low cost. These measure
should always be considered during any major- construction activity
ed Z 1Q%' Th1s assumes that 1nl^t contrS? devlws are not
the m°re stormwater that is throttled at the catchbasins
8'
most IrhJ Ii«« f decrease is relatively low and would be so for
?n !„«? A ! -, S9urce control management options would be more effective
in rural and developing residential areas. In these areas, the best option
can be constructed along with the planned structural and land develJpmenl
The needed space requirements are generally available in such areas
114
-------
SECTION 7
COLLECTION SYSTEM MANAGEMENT
MINIMAL STRUCTURAL IMPROVEMENTS
Objective
and frequency.
It should be noted that the term, minimal structural, is relative and_
structural measures.
It is essential to recognize that the improvements identified as minimal
I
1 f A partUl tructural approach may still
o
H?^0^^^^^
improvements. They would be for the structural alternatives.
At the heart of all of the identified minimal structural improvements is
be optimized prior to implementing any structural improvements,
115
-------
The minimal structural improvements discussed in this section include:
Selective structural improvements to the interceptor
Minor modifications and adjustments of most of the overflow regula-
9 the *xist;!n9 VanLare Treatment Plant under a split-flow
creased 10n * ^^ eff1cienc^ durin9 storm events is
Although the above identified minimal structural improvements ar* Hie
cussed separately herein, these control measures are compStaJy in their
Rivpf 1Vpf ^1H-r-d^'nVhe fre^^y and volume of CSO tS?he Genesee
River. Each individual element - interceptor improvements, regulator modi fi
?nvn?nSH WS1- he-9ht ^hanges' and ^^ow mode of VanLarellP operation
involved maximizing the use of the existing sewer conveyance and tfeatmln?
systems Although reduction in CSO's would occur upSn implementation of
u tl n SrE^illh^'^^V^^f5 are «ntt1MS rSIlS^o re-
auctions occur when all the identified alternatives are implemented.
Interceptor Improvements
Background—
(circa^r^^lHf thCtJSn °f -he.St' Paul Boulevard Interceptor (SPBI)
jcirca 1912), all of the then existing outlet sewers discharged directly into
the Genesee River at various locations north of the Upper Falls These out
^t^rt5;-^ termed ^Unk Sewers' conve^ed a11 wastewater flow from the
tLt !?th ^ Utar^ierV1Ce.areas to the River for disposal. It was evident
that with the rapidly growing population of the City of Rochester and sur-
rounding areas, in conjunction with the low flow in the Genesee Rl5Sr durina
4 scha'rqld^to0"^! r^l ^-^ (194 m9d)' Untreated sewagS co^d nS be 9
aiscnarged to the Genesee River on a continuous basis.
a t~J? d1*6rf S!Wage ?nterin9 the Genesee River and convey the wastewater to
ex£??Se^t? !nti ^ lntercePt1n9 ^wer was constructed to intercept ?hf
existing outlet sewers near their discharge outlets. The interceptor natu
rally followed the general course of the River. Construct Sn of aT'nSer-
cepting sewer in conjunction with treatment provided by a disposal p ant
''"'0 ^ the fl>
convevsittnhppu S,ewa9eTin the trunk sewers from the River and
nanf a i nf S6 I nk E;uVani;re Treatment p^nt near Lake Ontario. Origi-
nally, al of the dry-weather flow in the trunk sewers and two and one-half
co? ec?ed T nn?^etSh°f sttormfter run°ff generated dun'"9 ^in?all were
collected. To control the rate of wastewater diverted into the interceptor
from the trunk
-------
,.,_• '+.htn +ho SPRT These regulating devices consisted of
charge conditions with ™ ^e SPBI T hese reg wyastewater transfer to the
" ""
z - '-•
the trunk sewer to the interceptor.
circular cunette 3 ft wide.
encountered, the entire C1rcuf *^nce J^J!"^ Sheets'^The' former Genesee
erated during periods of rainfall.
,, .,:--,:
ting.
chamber at Ridge Road.
117
-------
N
T A R I 0
Figure 44. Location of flow-restrictive sections of the SPBI.
118
-------
frit chambers just prior to the siphons under the River at Cliff Street
s«.w.. *.*-« ki^&^rr^
ThP nnrtion of the SPBI from Ridge Road to the treatment facility was
the interceptor at the regulating chambers.
tire route.
To reduce the frequency and volume of CSO presently discharged to the
fied as follows and are shown in Figure 44:
The section of the interceptor from the Avenue B junction chamber
' to the in?ersection of Norton Street and St. Paul Boulevard
The interceptor siphons under the Genesee River from the Cliff
street Screenhouse to the Avenue B junction chamber
The si PS Under the Genesee River from the Glenwood Screenhouse
to the Avenue B junction chamber.
The siphons from the Glenwood Screenhouse to the .SPBI ar e Included as
fe
TJ^^
Screenhouse.
119
-------
§£
». 't
e
Jo
Jo
(194)
Jo
250
(162)
O
-4
200
(129)
150
(97)
IOO
(65)
5O
(32)
5>
05 "5
-j
1
S
§
SEGMENT
C D
I
o
o
§
LENGTH, FEET (TOTAL LENGTH=3S35O FEET)
Figure 45. Hydraulic capacity profile of the St. Paul Boulevard Interceptor.
120
-------
Any improvements or adjustments to the overflow regulators in an effort
house.
Field Survey—
VIF^
under the BMP program, an intensive field survey was conducted to deter-
efficient to use in computing flowrates and conveyance capacities.
for the portion of the interceptor originally known as the Outfall bewer.
Other portions of the SPBI showed similar comparisons.
121
-------
TABLE 35.
Segment
COMPARISON OF DESIGN TO FIELD MEASUREMENTS
ALONG THE MAIN INTERCEPTOR
Design
Slope (ft/ft)
A
B
C -
D
E
0.0025
0.0050
0.0050
0.0033
0.0100
Field Measured
0.00247
0.00512
0.00505
0.00300
0.00976
Note: Refer to Figure 45 for segment locations.
Rationale for Selective Interceptor Improvements-
d?y-w aS^tT^r^i^f tl0"' ^ ^"'"fl™ * lota"6"
ury weatner now (DWF) in the ESTS is approximately 40 cfs (26 mgd).
. ofoS T^l^£^^ S?iSBJ.Sutld d^l??e ^e vo1-
3in rfc f?nn mn^ u eatment Plant vanes between 270 cfs (174 mgd) and
122
-------
With the available elevation difference between the Avenue .B siphon out-
S.T-S chafer located at Avenue 'B; is approxma e y 3 rf, 87^).
IS9Sj;™ arSlS* s1P°o£ S ^HlO*^) for tS. sewer serving the
Carthage drainage area.
regulator modifications.
diameter conduit.
In summary to insure that a uniform maximum flow is maintained in the
Jffi&l^a^
presented in Section 9.
123
-------
TABLE 36. SELECTIVE INTERCEPTOR IMPROVEMENTS
Interceptor Siphons 3400 ?/.
Interceptor ^
Avenue B to
Norton Street 3400 fin
West Side Trunk Sewer Diversion .
Siphons 800 35
Projected Overflow Reductions--
QDDT T° 2uantify t?e frecluency and volume of CSO discharged from the present
wa?L.SySJTWlth-th? 1dent1f1ed flow-restrictive segments, simplified storm-
water mode mg simulations were conducted. The Simplified Stormwater Mode?
conjunct1on with the M
(1) Maplewdod
(2} East Side Trunk
3) West Side Trunk Sewer and Lexington
(4) Carthage
(5) Spencer
(6) Mill and Factory
(7) Front
(8) Central
coi* lrT*2° yer,S °f h?urly ra1nfall records (1954-1973) three years were
selected for model simu ation. These years included the maximum, minimum
J«?n^ iWX? re1?t!v?1to total annu^ precipitation within the 20 yr
tS? T hey' were:1' "^ ^ fOUr S6tS °f SyStem C0nd1t1°ns were eva^ua-
1. Existing SPBI with unimproved flow-restrictive segments and un-
modified regulators/weirs
2. Removal of flow-restrictive sections of SPBI with no modifications
to regulators
3' DMiSt1ng SPB! with modified regulators as implemented under the
BMP program (regulator adjustments and weir height increases)
4. Removal of flow-restrictive sections of SPBI with BMP modified
regulators and control structures.
124
-------
Central
Mill and
Factory
Front
East Side
(I) 'unless otherwise stcted, all
values are in million gallons
per nour
{ 2) Circles represent drainage
areas and regulators
(3) Circles labelled N- represent
end points of interceptor
segments
West Side
Lexington
Maplewood
Von Lore
Treatment Facility
Figure 46. Schematic of Existing Sewer System for City of
Rochester for SSM Analysis.
125
-------
Table 37 and Figure 47 summarize the model projected reductions in rsn
r ? o
ac? LraHS^r?d t0 the 1nte™r and erefore,Ihe ?eg? tors
actually establish the frequency and volume of CSO discharges. eyuiai:ors
JABLJ 37. SSM ANNUAL OVERFLOW VOLUM^JAND_fREQiejCL£ROJECTIONS
(MG) Duratio-n (Hrs)
Condition Min Yr Ave yr Max Yr Min Yr Ave Yr Max Yr
\ JSS }£° 202° 170° 2000 2690
3 tin JgS 202° 170° 2000 2690
3 930 1560 1840 1340 1520 2110
4 520 990 1140 750 1080 1330
r.tnn ™f? relation (Condition 3) by minimal (BMP) regulator modi-
If fhl ?Ha ?•?• HTa9e annu?1 overflow volume can be reduced by about 65%
If the identified, flow-restrictive segments are improved with no regulator
moderations (Condition 2) no reduction in the average annual overflow vol-
™
-------
LZl
s^daouoo
uepun aiunLOA
VOLUME OF OVERFLOW -M6
ro 4^
CO
o
888888888 888
8
g
o
\\v\\\\\\\\\'
zzzzzzzzzzzzzzzzzzzza
nil II i /I nil
ESD
= » s
Q
CD
ID
-------
event. The highest pollutant concentrations in CSO's generally occur within
H± il* P°rtl0n °f the d1schar9e usua1^ within the first 10 to §8 mln An
upgraded sewer system consisting of interceptor improvements and regulator
modification, would convey more of the initial portion of increased waste-
»M«»rtra-^«*-l/J,iy,Jn.1v,_JMj;T'l -..-.^J.^, j_l | . V*WWW
auring rainraii events, thereby capturing more of the
,nH ™e modeling Projections have been presented in terms of annual rainfall
and overflow reductions. Table 37 and Figure 47 illustrate the effects of
R veryStTeh.^PrpruntS °n.the redUCt1'°n °f CSO discharged to the Gene ef
till CSO rLnrt-i JJe lmPressive> but they are based on annual quanti-
™S-'f A redljction effectiveness resulting from SPBI improvements and BMP
modified regulators is greater when determined on annual or average cSndi-
tions because of the large number of smaller storm events in any given year
For the less frequent, larger storm events, the percent reductions in over-'
flow frequency and volume would be less than those indicated for annua? pre-
SJE •££" condltlons' Thls same relationship is generally valid for most
other BMP measures. Their implementation results in greatest potential
Other Considerations--
into^nn!Cipated CS° reductions to ^e Genesee River from implementation of
interceptor improvements and modified regulators results from additional
combined wastewater being collected and conveyed by the SPBI. For the iden-
tified system improvements, additional flow would be diverted into the
interceptor by the regulators located on the trunk sewers, but only to the
point where the interceptor remains unsurcharged. Although based on the
field survey of the SPBI a small amount of surcharge would present no adverse
errects on the combined sewer system. Sanitary sewer systems, as opposed to
rt*™ 5eWeu-!uS!ums: arf normally designed to flow full but not become sur-
charged. With the trunk sewer regulators providing the control over the rate
at which wastewater enters the interceptor, flowrates within the SPBI cln be
easily controlled.
Maximizing the use of the existing sewer conveyance system involves
keeping more of the intercepted stormwater runoff in the sewer system that
previously conveyed, which results in decreased CSO's. Because of this, the
identified BMP improvements result in additional wastewater volumes being
tiTnnt 1° ?h* Vantar? SIP- If these changes are to be viable alternatives,
the potential impact of the additional wastewater volumes on plant perfor-
mance had to be evaluated.
i A 4.We*:weat^er treatment plant performance evaluations were conducted which
led to ttesplit-flow mode of operation. This altered mode of operation is
discussed in detail in subsequent sections. All such performance evaluations
indicated that conveyance of additional wastewater flows to the VanLare STP
during wet-weather events would have no detrimental effect on plant perfor-
mance if the plant were operated under the split-flow mode
128
-------
A Step 1 USEPA Construction Grant was applied for and received for the
identif ^interceptor improvements herein. Work is presently ongoing (29).
Regulator/Weir Modifications
Background--
As indicated previously, the frequency and volume of CSO presently dis-
charaed to the Genesee River are dependent on the wastewater transfer rate
ft Resent CSO volume or frequency. This was shown in Table 37 under con-
dition 2.
The subsequent discussion describes the approach taken to selectively
rfe^^
t^
completed.
Field Survey-
As the first step in assessing the overall situation, a detailed field
requiring more structurally-intensive modifications.
flow through this section occurs under orifice control.
On the downstream end of the casting is a movable orifice plate that
can ooen fully or partially obstruct the opening. Movement of the Plate is
^
a: ssxsr*
therefore, controls the position of the orifice plate.
In coniunction with the float/orifice plate mechanism, a weir located in
the trunk sewer Sedately downstream of the steel casting and level sensing
cSndSn allows wastewater to rise to weir elevation before overtopping and
129
-------
Figure 48. Schematic of typical float-operated regulator.
130
-------
sewer.
A number of generalized remedial measures were identified as possible
modifications to the regulators. These potential measures included:
\\ Rep^HnS9theefloat/SHfice plate'with an electrically or hydrau-
3. Ausnthetar the position of the orifice plate
relative to float level
4. Altering the elevation of the overflow weir
Measures 1, 3, and 4 were considered to be practical under the BMP program,
while measure 2 was established as structurally-intensive.
Field inspection of the regulators led to the following conclusions:
all of the regulators operated in such a manner that under
capacities were available in the SPBI.
Some of the regulators do not function properly because of rust and
the corrosive sewer environment.
Most importantly, however, it appeared that many of the regulators
could be modified with minimal effort.
Hydraulic Analysis—
meters that were accounted for in the investigation included:
sirme size and shape of the incoming trunk sewer
' Election Ind size of the steel casting that allows wastewater
transfer from the trunk sewer to the interceptor
transfers wastewater to the interceptor
Table 38 presents a summary of the findings of the hydraulic analyses
for the overflow locations with float/orifice controlled regulators.
131
-------
TABLE
Name
Maplewood
Lexington
WSTS
Carthage
Mill & Factory
Spencer
38. OPERATING CHARACTERISTICS OF EXISTING REGULATORS
Site
7
10
11
31
21
17
Design Dry-
Weather
Diversion
Rate (mgd)
8
5
22
10
11
5
Design Wet-
Weather
Diversion
Rate (mgd)
5
3
19
g
14
4
Maximum
Potential
Diversion
Rate (mgd)
1 1
10
68
ifi
15
Rate Increase
Attainable
(mgd)
i n
1U
48
11
Note.
Maximum diversions were calculated on the basis of maximum orifice
and gate openings possible with existing regulator structural con-
figuration. For calculation of design wet-weather and maximum
achievable diversion, a pool depth elevation equal to that of the
crown of the incoming trunk sewer at the overflow dam was used to
establish maximum available head.
n ¥ If6 ,ei'9ht monitored overflow locations did not involve float/
controlled regulators. At the Front Street location (Site 22), there
originally was a float-activated regulator similar to the other structures
s™f?n«:S?nt yfrS' h°f Ve:' ^he fl°at and rad1al 9ate were removed anSthe
small steel casting replaced with a much larger opening. In addition to
these modifications the height of the overflow weir was substantially, in-
(* ( SooSQ •
from the trunk sewer (Inner Loop Tunnel) at Central
by conveying flow in an 18-in. diameter conduit
upstream of the overflow weir. The only other over-
involve a regulator is that at the ESTS, known as
this location, wastewater transferred from the ESTS
by a manually operated sluice gate installed in a
trunk sewer to the interceptor. A preliminary
so conducted for these structures. Table 39
Wastewater transfer
(Site 36) is accomplished
which starts immediately
flow site which does not
Seth Green (Site 27). At
to the SPBI is controlled
conduit leading from the
hydraulic analysis was al
summarizes the findings.
132
-------
TABLE 39 OPERATING CHARACTERISTICS FOR OVERFLOW
SITES WITHOUT REGULATORS
Wet-Weather
Maximum Diversion Rate
Site
Seth Green
Front
Central
27
22
36
84
42
8
Based on the findings of the hydraulic analyses, Table 40 presents the
regulator modifications that were subsequently implemented under the BMP
program.
TABLE 40. SUMMARY OF IMPLEMENTED REGULATOR MODIFICATIONS
Location Site _ Modification _ _
u „, ,,„„,! 7 Fixed radial gate in full open position
Seth G?een 27 Closed sluicegate to 50% of full opening
WSTS 11 Jone2
31 Fixed radial gate in full open position
17 Fixed radial gate at larger opening
cnnr
Mill & Factory 21 Fixed radial gate at larger opening
Front 22 Structural change required^
36 Structural change required-*
1 Regulator setting to be adjusted after implementation of identified
SPBI improvements.
2 Float-activated regulator removed-replaced with Hydro-Brake flow
controller.
3 See text.
No minimal changes to the WSTS regulator were scheduled because the ac
tual conveyance restriction was the siphon capacities from the Glenwood
ScreeSS to the junction chamber at Avenue B. Until improvements to these
siphons are implemented, no additional flow can be transferred to the inter-
ceptor from the WSTS.
As part of the overall BMP program a Hydro-Brake "l» ™s*1
sequent portions of this Section.
133
-------
flow tn th «B? V" S S?Ctlon °n 1ntercePtor improvements, the rate of in-
flow to the SPBI from the Front Street diversion chamber is presently satis-
factory Structural modifications are necessary, however, to provide for in-
flow hydraulic control. By controlling the inflow rate, upstream n-system
, -
and F™nt Street tunnels can be realized. nstalla-
of electrically-operated sluice gates, which can provide the needed con-
trol, were considered a structurally-intensive control option. Therefore
changes to the Front Street structure were not made unde? the BMP program! A
Gr;nt "as &}^ for and received for these structural
later
Based on downstream SPBI capacity and trunk sewer inflow rates, the
to 25 cfVhfi £?? ^f^1 T^(V1^ the Inner Loop tunne1) could be increased
,L:1? 1- 92}' .Althou?h the^ do n°t represent minimal BMP modifications,
several options for increasing the transfer rate include: a HUN:,,
Utilizing the 6 ft diameter unlined rock tunnel instead of the
18-1 n. pipe and providing a Hydro-Brake flow controller at the
upstream end to limit flow to the desired rate.
Replacing the 18-in. pipe with one of larger diameter.
Since these options represent structurally-intensive options, implementation
?L*l ™er Jas ;?* ™de under the BMP Program. Additional funding under the
USEPA Construction grants program should provide for these improvements.
Preliminary analysis conducted under the BMP program indicated that use of
the 6 ft tunnel appeared to be the most viable.
The Carthage combined sewer drainage area has been reduced in recent
years because of ongoing urban renewal programs, which also involve sewer
ho^J n!\h a?h!9e I. ove^ow Sue 31 - had been considered high-impacting
because of the high ratio of pollutant per unit volume of CSO. Since much of
the area is presently served by storm sewers, frequency and volume of CSO
should be reduced. The magnitude of this expected reduction could not be
determined from the BMP overflow monitoring program.
Sampling of the Carthage overflow, however, revealed that high total
pollutant loadings still exist. Therefore, although the wastewater transfer
rate should be increased from Carthage, interceptor and regulator hydraulic
evaluations indicated that structural modifications would be necessary to
optimize use of various conveyance systems. Based on the identified SPBI
improvements, a transfer rate of 35 cfs (23 mgd) would be consistent with
downstream conveyance capacities and also minimize the high-impacting
Carthage CSO. A partial, interim improvement should be made that was con-
sistent with minimal BMP concepts. Removal of the orifice plate/float
mechanism would allow for a maximum wastewater diversion rate of about 25 cfs
(16 mgd). This represents a 47% increase over the present transfer rate as
controlled by the orifice plate/float operating system.
134
-------
lop n thetrunk sewers
conditions.
23 .
, measures could be quickly taken to reHeve such
•
a:
1
^bU9«t?nd?ca?esSihe1sUes"t';nicn"weirincreaies'Were Implemented and the
magnitude of the change.
TABLE AT-SUMMARY OF WEIR MODIFICATIONS
Location
Site
Weir Height Increase - ft
Map! ewood
Seth Green
WSTS
Lexington
Carthage
Spencer
Mill&Factory
Front
Central
7
27
11
10
31
17
21
22
36
2.00
None
0.50
2.33
1,33
1.00
1.00
2.00
3.00
^ thP first steo in assessing in-system storage potential, a general
SlahtsTldintlfled n Table 41) and evaluated under static hydraulic con-
dU?Sns in the trunk sewers. The resulting storage volumes are conservative
in that the flow dynamics of the system were ignored.
135
-------
TABLE 42. IN-SYSTEM STORAGE VOLUMES REALIZED BY OVERFLOW
WEIRHEIGHT INCREASES
Location Site In-System Storage Volume - MG
Maplewood
Seth Green
WSTS
Lexington
Carthage
Spencer
Mill & Factory
Front
Central
7
27
11
10
31
17
21
22
36
0.05
N/A*
0.43
0.11
0.10
0+
0.12
0.16
0.23
No weir height increase was implemented at this location
Increase was negligible. lULduiun.
oVTp^
to utilize the proper method. By not considering a level pool as illustrl
ol two" andUrdePn^H-n"SyStem St°r?9e V°1UmeS can 'e overestimated yfacto^
of two and, depending on sewer slope conditions, by a greater amount (30)
Rationale for Regulator Modifications—
KDRtl0 Er°Vlue f?r.max1mum ^^ow into the St. Paul Boulevard Interceptor
(SPBI), thereby minimizing CSO discharged to the Genesee River the trSnk
sewer regulators required modification. Each regulator was evaluated with
respect to maximum potential discharge, resulting overflow d^charae rates
and ability of the SPBI to accept increased hydraul ic loads without induci
detrimental surcharge and backwater conditions in the in?ercepto? Al? o
Al o
^ modifications in aderence to 32
the.resf^
during storm events but become surcharged. Modifications wou d be made how
pollut ntafoaedPLo,he "°? ™f]™f™ ^ service areal ! wU^the^hi st °W"
pollutant loadings as determined by sampling of the CSO discharges. •
, . U ™.st be noted that the regulator modifications were effective in TP
Sn o* heasPBei°f it S™"™"""""" ?*• conveyancela acity"? JaVSs
sections or the bPBI. The first assessment in determining the feasibility nf
minimal regu ator modifications was a hydraulic analysis of the In Once
this evaluation indicated that additional wastewater rates could be convened
136
-------
Figure 49.
In-system storage volume estimations using the
level pool method.
137
-------
extent ^S'Sif • T'6" ™S mde °f the re9u1ators to determine the
extent of such moderations necessary to affect an increase in transfer rate.
Regulator/Weir Modification Effectiveness—
The effect on annual overflow reduction as a result of the realization of
Tin-system storage in conjunction with improved system regulation wa presen-
ted ln Table 37. Condition 3 involved the application of those BMP metres
such as minimal regulator and weir modifications. measures
true t^i?°n?hthSe ™del.projected overflow reductions were impressive, the
true test of the effectiveness of improved regulators and weirs was actual
culfbPr/f UCfi0nS' ?Crate dete™nation of overflow reduction was d ffi
thl £? I 6 °f Se!ura factors' These include the hydraulic conditions n
U,PH in fiSeWH^' ^ I°Cati°n °f the leve1 sensor monitor, ^d the equat Cns
used in flow determination. An initial attempt to determine the actual rl
ductions, monitored "hydrographs" representing the level of wastewater 1 the
trunk sewer immediately upstream of the overflow weir were utilized
Figure 50 shows a typical hydrograph for a storm event. As indicated
inaY*nH%rallel to,the.bo«om axis were drawn which represented tneoril
Jwpln !h J 1ncreased V?1r hei9hts- The a^ea bounded by the hydrograph be-
tween the two parallel lines represented the reduction in overflow volume
^ h -rha betW6en ^ h£dr°9raPh and the line representing the or -
Figure 50 illustrates the type of analysis discussed in the previous
paragraph As shown, the shaded area represented the actual overflow Sol ume-
whereas, the_cross-hatched area represented the reduction in ?SO vo?umf by '
cateS an RRr'lSt-^1^^ F^ th1s Part1cu1a^ event, this procedure indi-
cated an 88/0 reduction in overflow volume. The procedure illustrated in
Figure 50 overestimates the effectiveness of the weir height increase n re-
ducing CSO. This is because the level of wastewater in the sewer is not
dependent only_on the height of the weir but also on the wastewater flowrate
and the diversion rate at the regulator. Another approach to determining the
effectiveness of the regulator and weir improvements would be to use the
actual monitored trunk sewer hydrograph. The CSO monitoring system had been
acS?Uf?lStmeaSU!:h thS l6VeVf wastewater at the regulatorand no? the
actual flowrate in the sewer. Knowing the flowrate in the trunk sewer and
bl the ^u^tor, which was approximaed by
head/discharge relationship, the rate of overflow could be easily
fn^l"!c' -°r ! 91Vf It0m event' actual volumes C0u1d then be computerd
for events prior to and after weir modification.
° ™se*\th* anticipated effectiveness of the weir modi-
was used whereby, the monitored overflow data base was utilized A
statistical regression analysis was performed on the overflow data for each
51 t?,Tor those events occurring prior to after implementation of the weir
nrmll^tl0?5'^ ?D^nera1 tm?d of the resu1ts inch'cated that without im-
provements to the SPBI, as previously identified, that the regulator and weir
modifications as implemented under the BMP program reduced annual overflow to
138
-------
81.6
Shaded area represents actual overflows
0
5:OO
6:00
8:OO
9:OO IO:OO
I-OO
Figure 50. Example of effectiveness of increasing
overflow weir heights.
139
-------
the Genesee River by approximately 5-10%. This is in agreement with the
model projected results which indicated about a 7% reduction
mn5~10% was S1'gnificant because the regulator and weir
modifications were implemented at practically no capital expense That is
approximately a 10% reduction was realized by simply "f ne tSninq" the con'
veyance system. The actual effectiveness that could be Realized by othe?
municipalities depends on specific system conditions. Such factors as
Pa^nJ9 1n^rce?.tor and,trunk S6Wer "Pities, regulator capab?lt?es and
tclfuS ™dl!lcatlon» and various land use parameters will determine the
Iecfofnec pTofBM? "^ m1nima1 -laments which fall under he''6
Hydro-Brake Regulator Evaluations
Background--
The^device known as a Hydro-Brake has been shown to be extremely useful
in reducing the CSO potential during storm events. The device was first
described in Section 6 under Inlet Control Concepts. Specifically this de
tvofcaf "nl ^C?-tr°lleur ? rDSgUlate f1°W 1n a PredeteSlnU ma ner n a
JtSiSl Lnsjalla!10n' a ^o-Brake would be installed in the outlet of a
storage tank. Stormwater runoff would enter the storage facility throuah
oSSSn?hCaJCh£aSln?,a!!d sto™water in^ts and be temporarily drained"9 Flow
out of the tank would be controlled by the Hydro-Brake such that the ratP nf
he *"" "°Uld n" ^ceed the downstream sewer
seweriva1-HfK-' USed mostly on seParate storm
sewers, is valid for combined sewers to reduce pollution from CSOs. On a
combined system, an installation can be designed whereby an off-line storage
PrdS f°Vhe requ1red wastewater detention. This type of system 9
°f ^ ^ ^ Hydro-Brakf Demonstration
As part of the BMP study it was proposed to utilize a Hydro-Brake as a
regulator in p ace of the float-activated flow controlling system In ?his
H*?lSVnnal at-°n' wastewater detention was achieved by utilizing poten-
tiay available in-system storage. The Lexington regulator prior to the in-
nnw^r^ *Ee "y^-S^e hydraulically operated under orifice control
Flow through a Hydro-Brake regulator is theoretically governed by different
hydraulic condnons. Whereas, discharge through an oHflce Is dependent on
laPrape^S-aUl1- h3ad "nditi?ns such that large variations in head prodSce
large variations in discharge, for a Hydro-Brake, the head-discharge rela-
tionship is such that large changes in head cause relatively small changes in
discharge Thus, a system can be designed whereby the wastewater transfer
rate can be established so that the downstream sewer is not surcharged The
backed-up wastewater would be temporarily stored in the trunk sewer '
140
-------
Site Selection and Installation—
For this study an overflow site associated with a large tributary drain-
easily installed relative to site conditions.
After a review of the potential sites suitable for installation, the
^I^^L^'overflow location was selected. This site was suitable be-
upstream drainage area, potential for in-system storage.
River.
The Lexington Avenue Hydro-Brake unit ^ shown in Figure 51^ The unit
• A9 -in in diameter at the rear and tapers down to lo-in. towara tne ai^
ILral end Flow in the cunette of the Lexington Avenue sewer_was routed in-
cnarye en . n t u *„«„,•„« +-hQ hnttnm nf the tunnel to fit the in-
to
This curve represents the design head-discharge relationship. Actual
m^LSents were not available for accurate verification. In conjunction
with thS install^™ of the Hydro-Brake, the overflow weir at this site was
raiseS to ?ealze the potential in-systen, storage in the trunk sewer.
Figure 51. Hydro-Brake unit before installation.
141
-------
2O
IS
ui
O
4 "Z 10
5*
(as shown in Figure 51)
Hydro-Brake ._.
Orifice Control
{18" dia.)
Note: Orifice control based
on Q= ca
Hydro-Brake curve represents
design H/D relationship.
9 10 II ia 13
HEAD
(ft)
Figure 52.
Head - discharge curve for the Hydro-Brake
regulator at Lexington Avenue.
142
-------
Operation and Maintenance Requirements—
to the unit.
Figure 53. Photograph of installed Hydro-Brake regulator looking
at the inlet.
Anticipated Overflow Reductions—
overflow weir.
143
-------
Included in the model input data base were the total drainage area in
acres, a gross runoff coefficient, available in-system storage, and the waste-
water transfer rate from the Lexington Avenue trunk sewer to the interceptor
The area involved was 710 ac with an approximate overall runoff efficient
of 0.41. In-system storage varied from 0 to 0.50 MG and the transfer rate
varied from 0.01 to 0.40 MGH. These particular ranges for storage and trans-
fer rate were selected because they represented values ranging f?om presen?
conditions to somewhat beyond those resulting from weir height increases and
the installation of the Hydro-Brake regulator. increases ana
atinnn-3 pr?sentj the overflow volumes and durations for various combin-
ations of in-system storage and wastewater transfer rates. Figures 54 and
55 represent graphical presentations of the same data. Overflow was based on
an average annual rainfall year as determined by total precipita Jon.
TABLE 43. REDUCTION IN OVERFLOW VOLUME AND DURATION FOR VARIOUS
^^STORAGE/TREATMENT COMBINATIONS AT THE LEXINGTON AJSiiF SFCHI
Transfer Rate - MGH
Storage - MG 0.01 0.10 0.25 0.40
0
0.1
0.2
0.3
0.5
235
(693)
220
(636)
211
(591)
207
(562)
204
(552)
178
(425)
164
(360)
154
(322)
146
(285)
132
(257)
127
(240)
117
(215)
109
(192)
102
(171)
91
(148)
95
(143)
88
(131)
82
(121)
76
(no)
fi7
(88)
Note: Values are average annual overflow volume in MG, whereas,
values in parantheses are overflow durations in hours.
The results of the modeling indicated the following:
Prior to the weir height increase and the installation of the
Hydro-Brake regulator, the Lexington overflow regulator discharged
approximately 230 MG of CSO with a duration of almost 700 hrs.
Before implementation of these control measures there was essen-
tially no in-system storage and the float-activated regulator
allowed for about 0.01 MGH in terms of transfer rate
144
-------
Sfrl
-SA aumLOA
OVERFLOW VOLUME
(MG/YR)
-------
s
£T
e
CO
M01Jd3AO
Figure 55. Overflow duration vs. storage/treatment relationship
for Hydro-Brake regulator at Lexington Avenue.
146
-------
For the ranges in storage and transfer rate shown, an increase in
the transfer rate yielded a much larger reduction in overflow vol-
ume and duration than an increase in storage.
Increasing the utilization of potential in-system storage did not
have a pronounced effect on reducing the average annual volume and
duration of CSO.
Significant reductions in CSO were better achieved by increasing
the wastewater transfer rate than by increasing in-system storage.
Reduction in overflow duration occured at a faster rate than re-
duction in overflow volume for increases in transfer rate and
storage.
Based on an estimated in-system storage volume of_0.11 MG as a re-
sult of the weir height increase and an increase in the transfer
rate to about 0.25 MGH due to the installation of the Hydro-Brake
regulator, the average annual overflow volume and duration were re-
duced by 51% and 69%, respectively.
An effort was made to field calibrate the Hydro-Brake unit and to demon-
strate its effectiveness by measuring wastewater levels upstream and down-
stream of the regulator. A Manning ultrasonic level recorder had been pre-
viously installed at the Lexington Avenue regulator to determine the fre-
quency and magnitude of combined sewer overflow discharges. A Potable
Manning -ultrasonic unit was installed in the existing regulating chamber
immediately downstream of the Hydro-Brake unit. Although flowrates upstream
and downstream of the Hydro-Brake cannot be accurately determined with the
level monitors because of turbulent flow conditions, recorded wastewater
eve s were directly related to discharge rate. That s, quantitative head/
discharge relationship cannot be established but a qualitative assessment can
be made.
Figures 56 and 57 show the relationship between the upstream depth in
the Lexington Avenue tunnel and the depth downstream of the Hydro-Brake unit.
These fgures show that the Hydro-Brake regulator controls the discharge rate
from the trSnk sewer to the interceptor in the manner in which the unit was
designed. That is, large increases in depth in the trunk sewer are not re-
jected in the wastewater transfer rate to the interceptor as would be the
case if the regulator operated under orifice control. Additional head/dis-
charge curve verification is required.
SELECTIVE TRUNK SEWER INVESTIGATIONS
General
Closely associated with improvements to the SPBI and improved system
regulation were the inspections of the West and East Side Trunk Sewers Al-
though only a small percentage of the entire trunk sewer system for the City
of Rochester consists of unfinished rock tunnels, these tunnels represent
large diameter sewers. Substantial in-system storage could possibly be
147
-------
4.O
3.0
8.
Q
•o
I
o
Z
- 2.0
1.0
November 1,1980
Overflow Depth <
3.13ft
Depth Upstream
Downstream
12
13
14 15
TIME
( Clock Hour )
16
17
18
Figure 56. Relationship between upstream and downstream depths
at the Lexington Avenue regulator for the 11/1/80 storm.
148
-------
October 22,1990
Depth Upstream
Downstream
15
149
-------
Many sections of the WSTS and ESTS were originally constructed bv
ing through rock and were left as unfinished rock conveyancftunnlls Over
^ lapTfr^^^^LHar'd0"5!^^^1'0^^ t0 the^nt'o?" artia?Vroof
"u=edverse backwater """iM""* In the tunne! djrinfstorm
Inn
n . ,
devices were installed at various locations, potent al in-system sto?a5e
could be realized. To utilize these tunnels in a storage mdl of ooerltinn
the large amount of debris presently deposited at the invert must be^Sed
^^^
of ihl col-*
Field Surveys & Structural
WSTS ndESt??Tl1??pSei-nia9nVt-de and SSVerity °f reP°rted deficiencies in the
WbTS and ESTS, field inspections were conducted. It was originally thouaht
that these inspections could be accomplished by a field crew wSklw the
M°St °f the WS^S was inspected in JhlsSS how-
e accompse y a field crew wklw the
l!Sththf the *!nJel- M°St °f the WS^S was inspected in JhlsSS how-
tlons Sprffi^h- °t thS f 9umu1ated debr^ and resulting backwater condi-
tions precluded this type of inspection for the ESTS along Norton Street
WSTS—
Sho?s+the gei?eral Alignment of the WSTS and associated diver-
A ce and Gl\t^ptanCeHint° *5? SGWer Was made from a manhole lo^ted at
downstream In Intl! ll + * ncon£lnuo^ Physical inspection was conducted
downstream to Santee Street. A sharp increase in grade at this manhole loca
fd fUr-her JnsPect1on« Approximately 9800 feet of t™ WSTS was
Approximately 3600 feet of the tunnel portion, between Santee
T e™?0d AV6nUe' Was not walked« Withi" the unwalked sec??on of
Siia lamPln9.ln?pection at several manholes indicated no major strSc-
*-+ * ?r s]9mflcant sediment accumulation. Although some minor
deposits of rock and grit were observed at various locations throughout the
walked portion of the
-------
1ST
>|urui spis }.S9M Jioj. deui uoiieocn '89
,0016 =„ I :
OIHV1NO
-------
problem areas and the types of structural defects noted. The inspection in-
dicated that only routine sewer maintenance be conducted on the WSTS inclu-
ding cleaning and repair of minor manhole structural defects.
TABLE 44. WSTS PROBLEM AREAS
Location Problem
on & R'R> Incoming lateral needs repair
, i "Pfn»am of Four cast iron pipes protruding
Jay & R.R. from Crown 16_i8 in>
Clyde & Burrows Bottom starting to break up
slightly - some bricks missing
ESTS--
Inspection of the ESTS was conducted during February, 1980. Access in-
to the tunnel and the physical inspection were facilitated because of the re-
duced volume of dry-weather flow in the ESTS, which was accomplished by flow
diversion at two major upstream overflow locations. Installation of inflat-
able sewer plugs caused the normal sewer flow to backup and spill over up-
rJlT °^e^flow we1^' B? P™Per adjustment of various gates at the Thomas
Creek and Densmore diversion structures, the diverted ESTS flow was conveyed
to the VanLare Treatment Facility by the Cross-Irondequoit Tunnel and Pump
Station. Figure 59 shows the extent of the ESTS and the major diversion
M\J I II to •
The upstream portion of the ESTS was walked from Rocket and Edge! and
Streets to Norton Street and Maring Road, a distance of approximately 5900
ft. This^ection of the ESTS varies from 5.5 to 6.0 ft in diameter. The in-
spection indicated that no major obstructions or structural defects exist in
this section of the ESTS other than a large amount of grit. The ESTS up-
stream of Norton Street was originally constructed by open-cut and consists
therefore, of concrete pipe or brick formed sewer shapes. No structural
deficiencies were observed within the walked portion of the ESTS. Grit
accumulations ranging from 6 in. to 2 ft, however, were found.
Because of the large sewer diameters associated with the ESTS along
Norton Street, a physical inspection of the ESTS should have been conducted
initial field investigations, however, which started at the Jewel Street
overflow chamber, indicated that structural and deposition problems do exist
in the ESTS. The entire stretch of the tunnel along Norton Street could not
be inspected because of the depth of water in the sewer. Considering the
size of the tunnel and the reduced flowrate because of the two upstream
diversions, the resulting water depth should have been minimal.
From the Waring Road chamber at Jewel Street the ESTS is an unfinished
(unlined) rock cut tunnel constructed about 87 years ago. At several loca-
tions along the ESTS tunnel a portion of the crown has fallen leaving a large
152
-------
N
LAKE ONTARIO
Scale-. I =9100
Figure 59. Location map for East Side Trunk Sewer
153
-------
amount of debris at the invert. This debris is causing the flow to pond
creating several impassable sections. The worst sections relative to roof
failures and accumulated debris were toward the downstream end of the ESTS
Toward the upper end of the tunnel (near Waring Road) very substantial
deposits of grit and similar smaller material were observed. Figure 60
graphically presents the results of the inspection of the ESTS along Norton
Street. A uniform distribution of accumulated material was assumed between
each manhole.
lows:
The findings based on the field investigations are summarized as fol-
(1) Between Waring Road and Clinton Avenue the ESTS is in shale where-
as, the tunnel west of this point to the Genesee River is in sand-
stone.
(2) The ESTS in the vicinity of Portland Avenue and further east should
be more thoroughly inspected including coring to determine the
depth of rock cover.
(3) Initiation of selective rock-bolting and concrete (approximately
1700 feet) lining will stop current spauling and weathering which
in turn will insure a service life of the ESTS for a minimum of
50 additional years.
(4) A substantial amount of material (rock) has fallen from the crown
of the tunnel causing partial blockage of dry-weather flow This
leads directly to adverse backwater conditions at various locations
which prevented a complete physical inspection. The present con-
dition of the ESTS with the unfinished rock surfaces contribute to
the continuing accumulation of debris.
Based on the field investigations conducted under the BMP program, the
most flow-restrictive section of the tunnel results in a conveyance capacity
reduction of about 65%. The ESTS along Norton Street could also be utilized
as a storage tunnel, however, present debris accumulations reduce the poten-
tially available in-system storage by approximately 19%. Table 45 summarizes
these data.
TABLE 45. ESTS STORAGE AND CONVEYANCE CONSIDERATIONS DEVELOPED
AS RESULTS OF TUNNEL INSPECTION
CLEAN TUNNEL WITH DEBRIS
Storage Capacity - MG 4.53 3.77
Conveyance Capacity - CFS 113 39
Reduction of Storage Volume = 19%
Reduction in Conveyance Capacity = 65%
154
-------
en
cn
c
-i
fD
cn
o
fa
Q.
fD
C
3
t/)
0)
fD
-S
•a
fD
o
ffi
•g s
- I
i o
Original Crown
of Sewer
Water Surface
Current Crown
of Sewer
S
o>
^c
a
- Debris Level
- Tunnel Invert
O
-s
fD
l/i
C
-------
Impact of Tunnel Rehabilitation on CSO Reduction
Present disposition within the tunnel portion of the ESTS contributes to
more frequent CSO discharges than would occur if the tunnel were clean The
debris accumulations result in adverse backwater conditions severely limiting
the conveyance capacity of the ESTS during wet-weather events. The extent of
the impact of these accumulations on CSO drainage was, therefore, investi-
gated.
Several considerations involving the ESTS and future flow diversions to
the Culver-Goodman Tunnel system (under construction) merit discussion At
the three diversion points on the ESTS, future flows during wet-weather
events can be diverted through the Densmore and Thomas Creek structures into
the Cross-Irondequoit Tunnel. In addition, there are many overflow relief
structures proposed to be located on the ESTS, all upstream of Waring Road,
that will discharge directly to the Culver-Goodman Tunnel. Because of these
diversions, future ESTS flows during storm events will be lowered relative
to those presently occurring. Since little or no additional wastewater flow
"HI be 1n ,the ESTS downstream of Waring Road, if the tunnel portion of the
ESTS were cleaned and rehabilitated, greater in-system volumes and increased
conveyance capacities would be available.
> To determine the effectiveness of improving the ESTS, evaluations using
simplified stormwater modeling procedures were conducted. Based on the tri-
butary area to the ESTS downstream of Waring Road, modeling was conducted
using the total area, an estimate of average runoff coefficient, an assumed
in-system storage volume based on invert slopes, the objective to minimize
surcharging of the ESTS, and a bleed-off rate from the Jewel Street regulator
to the SPBI which is compatible with overall system operation. Table 46
presents the model input data, consisting of combinations of storage volumes
and regulator transfer rates, and the results relative to overflow frequency
and volume.
156
-------
TABLE 46 REDUCTION IN OVERFLOW VOLUME AND DURATION FOR VARIOUS
STORAGE/TREATMENT COMBINATIONS AT THE EAST SIDE TRUNK SEWER OVERFLOW
REGULATOR
Transfer Rate - MGH
Storage' - MG
0.17
0.58
1.17
1.75
2.33
0 172.80
(425)
2 15 68.60
(109)
4 30 31.60
(49)
6.45 12.80
(27)
87.45
(119)
28.90
(30)
7.25
(13)
0
(0)
44.70
(47)
10.30
(ID
0.70
(1)
0
CO)
26.45
(23)
4.40
(5)
0.10
(1)
0
Co)
16.50
(13)
2.25
(2)
0
(0)
0
(0)
Note: Values are average annual overflow volume in MG, whereas,
values in parentheses are overflow durations in HRS. Drain-
age area is 840 ac with a runoff coefficient of 0.39.
The present transfer rate was estimated to be between 0.58 and 0.17 MGH.
The exact rate could be easily determined because of the deposition problems
associated with the ESTS along Norton Street. Presently, there is no avail-
able in-system storage. Figure 61 shows that for no in-system storage ancTa
transfer rate between 0.17 and 0.58, overflow volume would be about 135 MG/yr.
With utilization of potential in-system storage, estimated at 2 MG and with a
reduced transfer rate to 0.17 MGH to be consistent with overall system opera-
tion as discussed previously, average annual overflow would be reduced to
approximately 75 MG/yr.
To fully utilize the ESTS for storage and controlled release, major re-
habilitation of the unfinished rock tunnel must be accomplished. USEPA Step
1 Construction Grants assistance was applied for and received for the
necessary rehabilitation work (29).
STRUCTURAL IMPROVEMENTS TO MAXIMIZE USE OF EXISTING SYSTEM
Control Structures
To utilize the large volume of potentially available in-system storage
within the existing and proposed sewer system network, installation of con-
trol structures at various locations will be necessary. The storage realized
by the installation of such control devices would then allow for flow atten-
uation, thereby decreasing the peak in-system flowrates generated during
157
-------
Figure 61. Overflow volume vs. storage/treatment relationships for
the East Side Trunk Sewer based on simplified modeling.
158
-------
storm events The net overall result would be a decrease in the volume and
frequency of'cSO presently discharged from the existing sewer system.
The concept of utilizing potential in-system storage was first conceived
and implemented under the regulator/weir modification effort as.part of the
More effective, positive control at selected locations within the existing
sewer system was^equired to utilize more of the potentially available in-
system storage.
Based on a review of the overall sewer network with respect to sewer
-------
N
LAKE
ON TA R|0
Sewer
Proposed Control Structure
Locations
Figure 62. Proposed control structure locations.
160
-------
TABLE 47 REALIZED IN-SYSTEM STORAGE VOLUMES BY THE
IAbLh TMSTAIiATTnN OF CONTROL STRUCTURES
Location In-System Storage Volume - MG
Lexington °* .-
WSTS " '?,
ESTS £•}£
Front u-j°
GVISW "'JU
control structures represent major capital improvements to the
sewer sstem They are not termed minimal-structural but rather structurally
intensive Although beyond the scope of a BMP oriented program, the metho-
rioloSv of'aDDroach to the problem and the solution - maximizing the use of
the existing system - fall under the general concept of BMP's. To implement
such a programf ulEPA Construction Grants funds should be applied for early
in an overall BMP study effort. Funding should include monies for Step I,
II, and III program phases.
SDPcificallv the types of control structures necessary at the identi-
fied iSStloS within the sewer system would be electrically operated devices
such as sluice gates and movable weirs. The sluice gates would provide the
control necessary to throttle the rate of wastewater discharge from the stor-
age tunnel to the downstream sewer element. The rate would be such as to
Prevent the possibility of overloading or surcharging a downstream section
which in turn would likely result in a CSO discharge.
Standby power generation would be provided at each site so as to insure .
nnsi five operation during periods of electrical power outages, which are
oossible especially during severe storm events occurring in the summer thun-
derstorm period? In any event, a fail-safe mode of operation would be in-
stalled tSinsure the structural integrity of the sewer system as well as to
Protect lives and property. That is, should all power be temporarily lost at
a oarticu ar site, the control device would automatically be placed in such
a Sslllon as lo Jrovlde the required hydraulic relief to avoid excessive
surcharging and possible structural damage.
To evaluate the effectiveness of the implementation of control devices
at the identified locations, simplified modeling using the SSM was conducted.
The effertoi overflow volume of in-system storage was Piously shown for
Lexington and the ESTS. To summarize the overall effectiveness. Table 48
presents the average percent reduction in overflow volume by site for an
average rainfall year.
161
-------
TABLE 48. CONTROL STRUCTURE EFFECTIVENESS IN CSO REDUCTION
Location Average Annual CSO Volume Reduction -
Lexington 51
WSTS 14
ESTS 47
Front 44
GVISW 86
Note: These values represent minimum percent effectiveness for the
installation of a control device at the downstream end of the
specific tunnel involved and operated such that no surcharge
occurs at this control location.
Control System
The basic objectives of this phase of the BMP program were as follows:
To develop a plan to incorporate the overflow monitoring system
into a system status component of an overall control system for
CSO control and management.
To determine the need, type, and number of rain gauges to be loca-
ted throughout the City of Rochester necessary to provide the
needed input data for control and management of CSO's.
To evaluate the need, type, and location of level sensing devices
to be installed at critical points in the existing sewer system to
actually install the devices.
To develop the operating logic necessary to implement and operate
a real-time control system for the conveyance system existing
whose present overflow points discharge to the Genesee River.
Also included was the development of the basic hydraulic model to
generate the required system parameters and projections to operate
the overall control system.
An important aspect of incorporating the overflow monitoring system into
a functional control system was the upgrading the monitoring and telemetry
systems so as to function properly and reliably. As discussed in Section 5,
the monitoring system, previously consisting of Badger Meter ultrasonic level
and velocity systems, was replaced with Manning Corporation ultrasonic level
recorders.
In addition to the replacement of the primary measuring devices, the
overall telemetry system was also upgraded. Early into the BMP program cen-
tralized control was deemed preferable over local control. To provide for
centralized control, telemetry had to be provided on all the major overflow
162
-------
monitoring sites with the data being sent to a computer centrally located.
The computer which was upgraded and modified under the BMP program, is loca-
ted at the VanLare Treatment Plant. All control and status functions would
be performed by one computer from this location.
The computer involved is a model PDP-8E manufactured by the Digital
Equipment Corporation. Upgrading of the computer consisted of Priding
additional core capacity, adding a disk drive, and incorporating an addition-
al computer display terminal. All of these modifications significantly
lipped the utility of the computer system to collect, store, and interpret
the telemetered system status data. Figure 63 is a photograph of the com-
puter facility dedicated to the BMP program.
After using the local rain gauge data for rainfall-runoff-overflow
correlations, it was apparent that the gauges, which were provided telemetry
capability under the BMP program, were not satisfactorily suited for main-
taining and operating a real-time control system.
The rain gauges only recorded in 0.1 in. increments. This increment is
not sufficient for the type of model input needed. The modifications that
wer"e imp emented, such as regulator and weir alterations, are effective when
consider ngsmal storm events. Furthermore, because of the characteristics
of the sewlr system, the implemented system improvements are effective over
?elatively small changes in rainfall amounts. Hence, the need for more accu-
ratl rain gauges. The present location of the eight local rain gauges is
adequate, more sensitive recording gauges are necessary.
To adequately assess the wastewater flows throughout the sewer system
network in order to optimize its use in minimizing CSO's; it is imperative
that In accurate and reliable system status monitoring system.bet^P^"^'
Under the BMP program, eight level monitoring recorders were installed along
the SPBI and several of the major trunk sewers. Each location was equipped
with te emetry instrumentation which allowed for direct data transmission to
the central receiving computer at the VanLare Treatment Plant These moni-
toring locations are identified in Table 49 and are shown in Figure 64.
Figur^TTomputer facility associated with the BMP program.
163
-------
N
LAKE
ON TA R|0
Sewer
In-System Monitoring
Locations
Figure 64. In-system monitoring locations.
164.
-------
TABLE 49. IN-SYSTEM MONITORING LOCATIONS
Location site
Pinegrove \
Zoo \
Beach \
Mill St. I
Hollenbeck £
Revine °
Clarissa 1
GVISW a
Note- Level sensor and telemetry system at the GVISW location were
installed during construction of the GVISW. Only a tie-in to
central computer was necessary under BMP program. All in-
stalled instrumental was ultrasonic level recorders manu-
factured by the Manning Corporation.
The selection of these particular sites was made on the basis of site
accessibility^ ease of installation and periodic maintenance, whether the
tS sewers on which they are located have significant potential ^-system
storage volumes, and at those locations along the SPBI, whether they would
provide the needed hydraulic information for system status and control.
Although periodic problems occurred throughout the in-system monitoring
program especially with the telemetry instrumentation, the overall data
collection and recording system generally worked satisfactorily and provided
the necessary data. In addition to establishing the necessary status system
for eventual control management, the in-system monitoring program also pro-
vided several other benefits. They were as follows:
Providing an indication of the actual utilization of sewer^onyey-
ance and storage capacities which was essential in maximizing the
use of the existing system.
Proving that such a monitoring system utilizing ultrasonic level
recorders and telemetry could provide the needed information for
formulating a real-time control system.
To illustrate the usefulness of the monitored in-system data to indicate
that the existing sewer system had additional capacity, Table 51 presents
thS maximum dejth of flow at the monitored sites for selected storm events.
165
-------
TABLE 50.
en
01
— — inuui. j«j. uumrvuu oioicn nUIUIUKtU UMIM
Rainfall
Date
5/13
5/18
5/31
6/01
5/13
5/18
5/31
6/01
5/31
5/18
5/31
6/1
5/13
5/18
5/31
6/01
5/13
5/18
5/31
6/01
Site
No.
1
1
1
1
2
2
2
2
3
3
3
3
4
4
4
4
5
5
5
5
Vol.
in.
0.32
0.40
0.47
0.40
0.32
0.40
0.47
0.40
0.32
0.40
0.47
0.40
0.32
0.40
0.47
0.40
0.32
0.40
0.47
0.40
Max Hr. Intensity
in/hr
0.14
0.12
0.25
0.32
0.14
0.12
0.25
0.32
0.14
0.12
0.25
0.32
0.14
0.12
0.25
0.32
0.14
0.12
0.25
0.32
(continued)
Max Depth
ft.
2.81
3.19
2.86
2.86
3.14
3.35
3.08
3.14
3.14
3.14
3.14
2.89
5.63
6.00
6.25
6.25
3.10
3.46
3.46
3.81
Flow
M6D
98
121
101
101
96
106
93
96
54
54
54
47
108
112
103
103
15
19
19
22
Depth % of
Total Pipe 0
51
58
52
52
52
56
51
52
57
57
57
51
90
96
100
100
35
40
40
44
-------
Date
en
Rainfall
Vol. Max Hr. Intensity
Max Depth
ft.
Flow
MGD
Depth % of
Total Pipe 0
-------
i iuw into me SKBI. i hat is, the SPBI under varying rainfall
eluding very intense storms, did not flow full. Excess «Mc
•;«
ss
all conveyance and treatment systems be optimized and CSO' f minimized
All of the collection system improvements identified in this
Slzr -H
?=: s ^rj
of all of the identified measures result in a
The structural improvements to the collection system outlined in this
ol Sma°?lW°^d be ,effe't1ve in Cueing annual CSO because of the large number
of small, low-intensity storm events which occur in any given vear THPSP
i-ntPpnI?tvntt' a1thOUf they WOUld decrease the vollne of 9CSO for high^
iJteS 2ul ^ntertS "s?ally Occurr1ng during the summer months to some
acrpnt,h?p ? i adequately reduce the pollutant loads so generated to
acceptable levels for discharge to the Genesee River The oroDosed tunnel
systems for the City of Rochester would address these h ghe^lutant loads
to meet water quality standards for the Genseee River (2) poMutant 1oads
The improvements outlined in this section are also comoatiblp anri rnmnn
jentary with the proposed tunnel system. Wastewaler voluS kept inlhe sur "
™ SyStem d° n0t require Pump1n9 to the treatment fac 11 tils
n ^
L ut n?n;,th- USS °I the tunnel system W0u1d be minimized by max mi zing
the use of the improved surface collection system. The tunnel system wuld
therefore, be operated for high-intensity storm events, thereby eliminating'
the frequent operation of the system which would result In maintenance costs
168
-------
IMPACT ON VANLARE TREATMENT PLANT
Concept
To realize the reduction in CSO's as a result of the implementation of
iSg increased flows to the treatment plant during wet-weather events, termed
split-flow, was developed under the BMP program.
In establishing the applicability of split-flow mode of operation, sev-
eral Ireftment plant parameters were evaluated. First, to assess the ability
of the existing facilities to adequately handle Increased.hydraulic oads
operated during storm events, a determination of the maximum hydraulic capa-
?lS Sfthe Si sting treatment plant was made. Second, a determination of
anyprocess limitations that may exist during increased loading rates was
made The D ant effluent must meet federal and state effluent standards re-
gies! oVthVinfl^ent flowrate. Third, to manage the treatment plant more
efficiently and economically during both dry- and wet-weather periods an
analysis of plant operation and performance was conducted under the applica-
tion of a split-flow mode of operation.
Serall ?ltnt performance, in terms of effluent quality, was realized when
the plant was operated under the split-flow mode.
Evaluation
Analyses of the treatment plant performance data were conducted to de-
velop theprocess models necessary to evaluate various modes of operation of
the existing facilities. In particular, process models were developed to
oredict the response of the primary settling units, biological clarifiers,
and an optimal utilization of both primary settling and biological facilities
employed under a split-flow mode of operation.
The configured models were primarily developed through the application
of stattst?cal9regression techniques using 1977 plant operating data. The
process models and modeling assumptions are presented in Table 51 The con
ventional biological BOD removal efficiency model was developed based on
the response of ihe existing system to changes in the influent wastewater
composition, wastewater flows, and mixed liquor composition.
The results of the modeling efforts are presented in the form of Figure
65.
169
-------
O.
w
UJU.
O
u
o
CVJ
+8
CVI
CJ
\
o $
<£ 5
cvj
O
O
o
00
o
in
(O
O m
ro cvi
(1/9W)
1 1 1
o in o o
SS30X3 NI aoa
Figure 65. Model projected VanLare plant effluent quality for
varying hydraulic loadings under split-flow mode
of operation.
170
-------
TABLE 51. PROCESS MODELS AND MODELING ASSUMPTIONS
Conventional Primary BOD Removal Efficiency
- 79.6 (0.82) e-
-------
TABLE 52. PRELIMINARY TESTING PROGRAM SPLIT-FLOH MODE OF OPERATION
' Week
Split-Flow (Primary Settling
to Biological
1
2
3
4
5
6
7
8
9
10
1.10 (5%)
1.20 (10%)
1.30 (15%)
1.40 (20%)
1.50 (25%)
1.60 (30%)
1.70 (35%)
1.80 (40%)
1.90 (45%)
2.00 (50%)
Note: Assumed average influent flow of 70 mgd. Measurements
included TSS and BOD for plant influent, primary settling
influent, primary settling effluent, and biological process
effluent. On the portion of the flow that was split,
similar parameters were measured on composite samples
taken from the same location at two hour intervals.
TABLE 53. EVALUATION PROGRAM SPLIT-FLOW MODE OF OPERATION
1. Flow Measurement
Primary settling influent - acquired via existing meter readings
Primary settling treated split-flow-acquired via velocity and
head measurement at point of confluence of the biological
process facility bypass and the biological clarifier
effluent launders. This method of flow measurement in-
volved cross-sectional area and velocity determinations.
Biological process treated flow - to be obtained from the above
two measurements and available recycle data.
2. Frequency of Flow Measurement
The bypass gates requiring adjustment will be set at the begin-
ning of each week and the flow determined on a daily basis.
3. Frequency of Sample Collection
A minimum of 4 times daily at the hours of 12 AM, 6 AM, 12 PM
and 6 PM. Composite samples were collected of plant influent,
primary settling influent, primary settling effluent, biological
process effluent, and the chlorine contact chamber effluent.
(continued)
172
-------
TABLE 53 (continued)
4. Analytical Requirements
As outlined in Table 52.
5. Method of Providing Split-Flow
Adjustment of the basin by-pass gates achieved the optimum
process flow distribution to the biological processes in keeping
with the desired daily average primary settling to biological
process flow ratio.
6. Dry-Weather/Wet-Weather Operation
The valve settings were set based on daily average flow and were
not adjusted during the processing day. Diurnal variations in
plant inflow were minimized by pumping from the Cross-Irondequoit
Pump Station. The valve settings were maintained during wet-
weather flows in order to evaluate performance under a range
of hydraulic conditions.
7. Data Logging
A log with the following minimal information was maintained:
1. Date and time of flow measurement
2. Influent plant flow
3. Primary settling influent
4. Split-flow ratio
5 Reference settings of the necessary bypass valves
6. Head measurement and velocity measurement in biological
process effluent launder
7. Notation as to whether sample was taken
Analysis
The data compiled on the split-flow demonstration program over the
period of 8/28/78 to 10/4/78 was analyzed with respect to effluent total sus-
pended solids concentrations and percentage reductions of BOD. The data
shown plotted on Figures 66 and 67 indicate a fairly strong relationship
between effluent parameters and the percentage of split-flow under dry-
weather conditions. The projection of data to the 30 mg/1 effluent TSS level
indicates that a 25-30% split-flow under dry-weather conditions may be justi-
fied.
An analysis of the corresponding BOD data indicates a 20-25% decrease
in BOD reduction under a 25-30% split-flow hydraulic regime. Phosphorus
data were analyzed in a similar manner.
173
-------
Average Effluent TSS (mg/l)
--~J
*i
c
-n O
CO
C
CD
cn
CTl
Ol-
-h CO
— >-a
Q — '
rt-
O 1
0 -h
3 — i
O- O
— J* £
o co
3 CO
• TD
fD g?
-h
O O)
3 "2. —
pi 5: Ol
3
0 Tl
f
Q. *
CD
fa
c: M .
3 0
Q.
fD
-s
Q.
-s
1
n> ro
o> Ol'
3"
n>
-s
OJ
) 0 0 c
»
-Qrff)
ov^
\
\
\0
5 o
1
\
\
\
\
0 \0 Q
00 \ °
\
\
\
\
\
• \
^B. ^k
• »
\
^
\ * 1
XV
X x
\
1 1
x v
x \ x 1
X v
* 1
\
v 1
t X
X
\ J
%
\
\
V
>
O
»
-------
100-
90-
80-
70-
c
o
5 60-
1 50-
Q
o
CQ 40 -
30-
20-
10
0
l
"~ ' X
^^^_
^v
*^\
3 5 10 15 20 25 30
% Split Flow
Figure 67. Split-flow BOD performance data under dry-weather
flow conditions.
175
-------
_ A problem encountered during the split-flow evaluations was the lack of
rainfall necessary to generate higher plant flows. Since the percentage of
split-flow decreased significantly under higher hydraulic loadings, attempts
were mate to adjust the biological process bypass gates immediately prior to
rainfall in an effort to evaluate split-flow percentages under wet-weather
conditions.
_ Only one day of high hydraulic loading was experienced during the test
period. On September 12 an average daily flow of 114 MGD was recorded with
a peak flow of 134.1 MGD measured at 12 PM. The percentage of split-flow
during the test period was 5.9% and, as such, was too low to evaluate the
effectiveness of the split-flow mode of operation. The collected data, how-
ever, indicated the need for a split-flow method of operation. Figure 68
shows that the relative quality of primary settling effluent increased as
the flow increased. In contrast, the quality of the biological process
effluent decreased with the passage of biological solids associated with
higher hydraulic loadings. The application of a split-flow mode of
operation prevented the occurrence of a situation in which the plant
effluent quality is less than that of the primary settling effluent.
The split-flow mode of operation evaluations conducted in 1978 were
based on modifying the hydraulics at the treatment plant. Beginning in
early 1979, chemical assisted primary treatment in conjunction with the
previous split-flow mode of operation was introduced.
The modified split-flow mode of operation was evaluated over a six
month period using approximately 20% split-flow with coagulant addition
to provide partial chemical-assisted, primary settling treatment to the
split-flow. The purpose of the coagulant addition was to reduce the
total inorganic phosphorus and colloidal BOD and TSS concentrations
associated with the split-flow. in.eiiurai.ions
On January 18, alum was added to one of the primary settling basins
to achieve an average alum dosage of 100 ppm. The addition of the alum
was assisted by high-energy mixing within the distribution launder. The
addition of alum created a pinpoint floe which was found to be most
difficult to settle. On February 8, a dosage of 0.5 ppm of an anionic
polymer was added to the alum-treated, degritted wastewater just prior
to the primary basin. The dosage of anionic polymer was established
based on jar tests.
11 +J"he Average operating performance data for the period of February
11 through June 3, 1979 are presented as Table 54. The weekly average
Rnn yr^°W nT™9 2? ^valuation period was 106.2 MGD with an average
n ftfi In effluent concentrations of 28.7 mg/1, 25.7 mg/1, and
^,fL 9/ 5/!S2?Ctlvely* These Perf0™ance data were obtained under an
average split-flow percentage of 25.858. The detailed performance data
are presented in the form of Figures 69 and 70 H*r.unnance aata
176
-------
UJ
:*:
23
ylj
U. UJ
!£
s o
— o
(T UJ
0,01
xo
/
o
(a
o ~
— o
o S
- I
. ,o
o
o
o
0)
o o o o o
O OS 00 ^« (O
(I/6UJ) SSI
o o
-------
• ^
O O
-------
So o
CD f-
•o|j »H«S '
o o
01 —
09W '«
•£Q/B
•a/9
•02/S
•ei/s
••90/S
33/fr
•HI/*
S g ? S S 2
eooooooooo
O)COP~ICIO^rQCJ —
ssx won-
l/>
•S3/S •,
<
si/e
•52/3
81/2
HI/2
•V/2
•62/1
JS/I
i/\
•IE/21
;/2i
•il/2l
One Fin
anK Ou
|||(
o i1
.1 °£
1<~
Figure 70.
TSS effluent concentrations under chemically assisted
split-flow mode of operations.
179
-------
TABLE 54. SPLIT-FLOW ANALYSIS OPERATING PERFORMANCE DATA
2/11/79 - 6/03/79*
Weekly Average Daily Flow - 106.2 MGD
BOD - 28.7 mg/1
TIP - 0.86 mg/1
TSS - 25.7 mg/1
% Reduction TSS - 77.5
% Split Flow " - 25.8
Note: The data for 3/25, 4/1 and 4/8 were eliminated due
to operational difficulties with one final settling
tank out of service during these weeks.
Review of the performance data indicated that the effluent TSS was
largely independent of the daily average influent flow to the plant, even at
flows up to 158.7 MGD. The only exceptions were two periods which were con-
trolled more by hardware modification, i.e. the weeks of 3/25/79, 4/1/79 and
4/8/79 in which one final settling tank was out of service. In addition,
the effluent TIP concentration of 0.86 mg/1 was well under the permit stipu-
lated level of 1.0 mg/1.
The largely independent response of effluent quality to the hydraulic
loading to the plant was a change from the historical dependence of the
plant on hydraulic loading which is presented as Figure 71. Comparison of
the Phase II split-flow program results with the historical performance
clearly indicated the advantages of the split-flow mode of operation in re-
ducing the deterioration of plant performance at daily average flowrates en-
countered during wet-weather events. :
Figure 72 presents the point of addition of both alum and polymer to
the VanLare Treatment Plant process train and the ultimate disposition of
the chemical assisted, primary settling treated split-flow. Also shown on
Figure 72 are the valve operators and metering facilities that were nece-
ssary to optimize and facilitate the split-flow mode of plant operation.
A summary of the conclusions and recommendations associated with the
split-flow mode of operation at the F.E. VanLare Treatment Facility is as
follows:
1. The demonstration data indicated that the split-flow mode of operation
of the treatment facility under conditions of 25-30% split-flow allowed
attainment of the following effluent characteristics under daily aver-
age flows in excess of 150% of the rated process design capacity:
effluent BOD 20-25 mg/1
effluent TIP 0.75-1.00 mg/1
180
-------
181
L OLLneupAj uo
aouapuadap
% Reduction BOD5
o •
8-
g-
0 '
O)
o •
5 8-
o
0 CD .
•— O
8-
o •
o
5 '
o
8
•»
o
§
55
o
Ol Ol 0) 0> -J -4
o 01 o 01 o 01
-
CD 00 <0 «0 O
O W O Oi O
1
1
t> 1
o m O/
-f o/
fa o'o
*l / 0
I ^i °
g ---i "O
• /'
/
o
o
m
-••
c
-------
N
0 •*•
J- §
J*U|JO)0 (JOpuoMg -
||
£ £
J
0
in
c
c
i
i
CD
S
*
O
0.
in
0)
= 1
__!
;
« °
If
a. ;
5
to
o
UJ
>,
a
a.
in
in
o
m
i_
II
1 I
z? S.
li 1
Em =
• •§ s ri-'i
|li| [jii
o
h.
z
s
Figure 72. Split-flow valving and instrumentation requirements.
182
-------
2 A comparison of the split-flow mode of operation to the normal mode of
' operation of the treatment facility indicated significant improvement
in average effluent quality associated with implementation of the split-
flow operating concept. The split-flow performance was based on data
obtained during the spring of 1979 while the baseline period was the
spring of 1978.
3 The split-flow mode of operation provided the flexibility of meeting
effluent limitations under a much broader range of hydraulic loading
conditions than available under the normal mode of operation.
4 The use of alum, in conjunction with an ionic polyelectrolyte at con-
' centrations ranging from 50-100 mg/1 and 0.5-1.0 mg/1, respectively,
overcame the BOD and nutrient effluent quality Jim1tatl;ns.experienced
under the initial demonstration work conducted during the fall of 1978.
5 To facilitate the full scale implementation of the split-flow mode of
' operation, facilities should be provided to store and meter alum and
polymer. The point of addition should be modified so as to_provide
flash mixing at the point of alum addition and adequate mixing floccula-
tion energy at the point of polymer addition.
6 Appropriate instrumentation including four valve operators, controls,
and an additional flow meter needed to facilitate the effective control
of the split-flow mode of operation of the treatment facility should be
installed.
7 Only by operating the treatment facilities under the split-flow mode
can the plant effectively treat wet-weather flows from the present _
collection system. Without additional stormwater treatment facilities,
the present treatment facilities cannot handle the increased volume of
wet-weather flows generated from the implementation of the BMP system
improvements except under the split-flow mode of operation.
8 The split-flow mode of operation offers an acceptable means of de-
' creasing the costs associated with the treatment of dry-weather flows
while achieving the discharge permit stipulated effluent quality of
BOD, TSS, and TIP. Furthermore, the split-flow mode of operation offers
the only cost-effective method of attaining the TIP effluent standard
under dry-weather conditions.
9 For treatment plants serving combined sewer systems, effluent discharge
limitations should be established on the basis of pollutant mass load-
ings and not on a concentration basis. In any event, limitations
presently based on the generally accepted standard of 30-oO and bb/0
removal (R) should be abolished. The 30-30 refers to 30 mg/1 BOD and
TSS computed as an average over any 30 consecutive day period. A
limitation involving both 30-30 and 85% R assumes that the influent
solids concentration is 200 mg/1. For plants receiving less than
200 mg/1 TSS, to meet the 85% R limitation, implies that less than 30
mg/1 BOD and TSS can be discharged. This would not be equitable to all
biological process treatment plants.
183
-------
SECTION 8
RECEIVING WATER STUDIES
BENTHIC DEMAND
Background
One of the major objectives of the BMP program was the identification of
dissolved oxygen (DO) impacts on the Genesee River resulting from CSO's. The
data gathering effort was, therefore, directed toward identifying both the
immediate and transient impacts attributable to the CSO itself as well as
establishing the long-term impacts associated with the build-up of benthic
sludge deposits.
Dissolved oxygen impacts attributable to storm runoff pollutants have
been difficult to demonstrate conclusively in any area in the country, al-
though justification of most abatement facilities is primarily based on miti-
gation of such impacts. Reasons for this difficulty have been the logistical
problems associated with monitoring transient, short-term storm events, the
complexity of runoff-loaded river systems, and a rudimentary framework for
the analysis of benthic oxygen demands. Velz, through laboratory experiments,
made significant contributions in mathematically describing the long-term
effects of benthic oxygen demands (31). However, his results did not fully
address the issue of the original source of benthic deposit material.
Methods have recently been developed for measurement of benthic demands, on-
site or in the lab; however, the lack of a rigorous description of the sludge
build-up process prevents water quality projections under varying natural
conditions.
To build on these deficiencies, the receiving water impact investiga-
tions conducted under the BMP program involved the establishment of a con-
tinuous water quality monitor for dissolved oxygen and turbidity determina-
tions in the water column, as well as the placement of sediment traps to en-
able the measurement of specific constituent concentrations and sediment
oxygen demand (SOD). Locations for these monitors were selected to show the
effects of CSO's in terms of water column deoxygenation from benthic sludge
accumulation. Projections of receiving water DO concentrations were made
using a previously developed Genesee River, steady-state DO model with up-
dated data obtained under the BMP program.
Immediate impacts of soluble organics in CSO's were to be identified
from transient DO depressions recorded during both previous water quality
surveys and as shown by the recently installed water quality monitor. Im-
pacts resulting from the settleable materials in the overflow were determined
184
-------
from the variations in rate of accumulation and constituent concentrations
found in the sediment, as well as variations in the rate of sediment oxygen
uptake.
Field Program
Measurement of sediment buildup and benthic oxygen demand was accomplish-
ed by the installation of five sediment traps along the Genesee River as
shown in Figure The exact locations are identified as follows:
1. Upstream of the Elmwood Avenue bridge .
2 Downstream of the Eastman Kodak treatment plant (approximately 200
ft downstream of the plant effluent discharge) _
3. Boxart Street (most southerly point of commercial shipping along
the Genesee River)
4. Stutson Street Bridge
5. Upstream of the Eastman Kodak Treatment Plant
These sites were selected to best indicate both the transient and long-
term impacts of CSO's on receiving water quality in light of the varying con-
ditions along the Genesee River. Location 1, immediately upstream of the
Elmwood Avenue bridge, represented the portion of the River upstream from CSO
discharges. At this location, the river was characterized by low velocities
and the widest channel section as it passed through the City of Rochester.
Location 2 represented the first reach of the river immediately down-
stream of all major CSO and storrawater discharges. This site was also down-
stream of the three falls occurring within the City of Rochester. The river
within this reach was characterized by a narrow, deep cross-section. River
velocities are low, except during large storm events, causing much of the
settleable material that was carried downstream through the city to settle
out.
Location 3 represented the most southerly, navigable point along the
Genesee River. Commercial shipping operations were conducted upstream to a
point opposite Boxart Street. The river channel from the mouth at Lake _
Ontario to this sampling station was maintained by the Army Corps of Engi-
neers. Annual dredging operations were conducted between mid to late summer.
The most downstream location, Site 4, represented the portion of the
Genesee River characterized by very low velocities and occasional current re-
versals due to the influence of Lake Ontario. It also represented that por-
tion of the river where maximum DO depressions were previously predicted and
measured.
These four locations adequately represented the varying conditions along
the river to properly assess the urban influence on sediment quality. How-
ever, after initial sampling, it was determined that fluctuations in the
quality of the Eastman Kodak Treatment Plant discharge can disguise the
effect of CSO's on SOD. Therefore, a decision was made to install a fifth
sediment trap immediately upstream of the plant's discharge.
185
-------
SEDIMENT TRAP
OVERFLOW POINT
Figure 73. Sediment trap locations,
18G
-------
To obtain representative data at reasonable cost and to allow for easy
site access for periodic sample collection and maintenance, a simplified
approach was adopted and implemented. Sediment traps constructed of plexi-
glass and provided with heavy weights as anchors were lowered into the river
at the five identified locations and allowed to rest at the bottom. The lo-
cation of each trap was marked with the use of a buoy attached to the unit.
Figure 74 shows the general configuration of each sediment trap. Sampler
inspection and sediment collection were accomplished by use of a winch
mounted on the back of a small boat. Figure 75 shows the operation of re-
moving a trap for sediment measurement.
An evaluation plan was developed and an optimum data collection schedule
adopted. Each trap was attended to on a biweekly basis, except that after
large storm events, traps were inspected to insure that they were not washed
away or had tipped over. Table 55 presents the evaluation plan for the
benthic demand studies.
TABLE 55. BENTHIC DEMAND STUDIES EVALUATION PLAN
Week
Sedimentation
Rate Determination Maintenance
Sediment
Analysis
Benthic Oxygen
Demand
1
2
3
4
5
6
7
8
9
10
11
12
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
TSS, VSS
TSS, VSS
TSS, VSS, Pb X
Zn, Cd, Hg
TSS, VSS, Pb X
Zn, Cd, Hg
TSS, VSS, Pb X
Zn, Cd, Hg
TSS, VSS, Pb X
Zn, Cd, Hg
Method of Analysis
To determine the rate at which sediment accumulated in the traps, a
simplified approach was adopted. Every two weeks when the traps were in-
spected a sediment depth measurement was made. Since the material collected
seldom was uniformly deposited over the bottom of the trap, depths were
taken at various points over the trap bottom and the results averaged.
After the depth measurements were recorded, most of the clear water in
the trap was then poured out until a known volume of sediment and water re-
187
-------
Figure 74. Sediment trap prior to installation.
Figure 75. Removal and inspection of sediment trap.
188
-------
mained. This volume was then mixed thoroughly until no visible sediment re-
mained on the bottom. From this mixture, a sample was collected and taken to
the laboratory for the required analyses.
SOD determination was made by establishing an oxygen depletion curve in
the laboratory for collected trap sediment. The collection process involved
obtaining a quantity of accumulated trap sediment prior to mixing of trap
water required for other analytical analyses. This procedure was considered
adequate, since much of the benthic oxygen demand is exerted by the top layer
of sediment.
To delineate the impact of CSO's on sediment quality from those impacts
induced by the Kodak Treatment Plant discharges, a fifth sediment trap, iden-
tified as Site 5, was installed in 1979. The Army Corps of Engineers summer
dredging operations along the Genesee River from the Boxart location (Site 3)
to the mouth of the river created some initial installation and maintenance
problems but these were subsequently resolved.
Results
The sediment trap data collected under this program are presented in
Table 56 The data include the observed sediment depth along with the total
and volatile solids for each of the sampling dates. Both adverse weather and
occasional river conditions precluded data collection from the 12 storm
events set forth in the implementation schedule. The dry weight sediment
concentrations for lead, cadmium, zinc and mercury are also shown. It is in-
teresting to note that the Elmwood sampling site (Site 1) had no measurable
cadmium and the lowest measured lead concentrations. In contrast, the first
monitoring site downstream of CSO discharges (Site 2) has the highest meas-
ured lead concentrations and significant cadmium concentrations.
Heavy metals were used as tracers, that is, the presence of heavy metals
in the river would be indicative of similar parameters associated with urban
stormwater runoff.
The profile of the heavy metal sediment concentrations is better under-
stood by analyzing the data presented on Figure 76, Figure 76 presents the
sediment concentrations for lead (Pb), cadmium (Cd) and mercury (Hg) and the
percent volatile solids as a function of distance from the mouth of the
Genesee River. The portion of the river between mileposts 5 and 10 received
CSO discharges. This same portion of the river was also characterized by
high velocities. In contrast, the portion of the river between mileposts 0
and 5 was characterized as quiescent and, therefore, condusive for sediment
deposition.
Figure 76 illustrates an example of a river with uncontaminated sedi-
ments upstream of an urban area. Both stormwater and CSO's discharge to the
river during periods of wet-weather as it passes through the urban area. The
heavy metals in these discharges are predominantly in a particulate form
which settle in the lower reaches of the river. Because of this characteris-
tic, an exponential fall-off of the sediment metal concentrations as a
189
-------
TABLE 56. SEDIMENT TRAP ANALYSIS
o
Site No.
Elmwood
Kodak (down)
Boxart
Sampling
Date
6/26
7/11
7/24
8/08
8/21
9/11
9/25
10/10
10/23
6/26
7/12
7/24
8/08
8/22
9/11
9/25
10/10
10/10
6/26
7/12
7/24
8/08
8/22
9/11
9/25
10/10
10/23
Sampling
Period
Days
13
15
13
15
13
21
13
13
12
15
16
12
15
14
20
13
13
12
N/A
16
12
15
14
20
13
13
12
Sediment
Depth-In.
0.13
0.13
0.13
N/A
0.13
0.25
0.75
0.13
0.75
0.25
0.25
0.13
0.38
0.25
0.50
4.00
0.25
1.00
N/A
0.75
0.13
0.75
0.50
0.38
0.38
0.25
0.75
(continued)
TS g
96
19
24
39
46
94
963
266
N/A
26
107
31
69
65
323
1377
263
N/A
N/A
910
20
153
167
87
146
526
N/A
VS g
9
2
2
4
3
8
59
19
N/A
3
9
3
6
6
26
233
22
N/A
N/A
48
2
9
14
7
13
37
N/A
Hb
48.0
0.0
38.8
50.0
32.1
42.8
N/A
N/A
N/A
94.0
97.3
176.0
143.7
82.6
119.0
N/A
N/A
N/A
N/A
13.4
61.5
112.0
116.0
108.0
N/A
N/A
N/A
mg/kq
Cd
0.0
0.0
0.0
0.0
0.0
0.0
N/A
N/A
N/A
0.0
14.7
14.2
20.8
17.0
8.4
N/A
N/A
N/A
N/A
2.9
0.0
18.7
18.6
19.7
N/A
N/A
N/A
dry wt.
Zn
275
510
589
250
289
276
N/A
N/A
N/A
594
349
690
633
448
238
N/A
N/A
N/A
N/A
49
661
503
416
444
N/A
N/A
N/A
Hg
2.00
0.0
1.55
2.60
0.80
0.80
N/A
N/A
N/A
1.67
0.00
0.00
0.00
0.70
0.00
N/A
N/A
N/A
N/A
0.05
2.16
0.70
0.20
0.70
N/A
N/A
N/A
-------
Site No.
Stutson
4
Kodak (up)
lAAULL. vJU
Sampling
Sampling Period
Date Days
6/26
7/12
7/24
8/08
8/22
9/11
9/25
10/10
10/23
6/26
7/12
7/24
8/08
8/22
9/11
9/25
10/10
10/23
15
16
12
15
14
20
13
13
(trap 12
lost)
15
16
12
15
14
20
13
13
12
Sediment
Depth-In.
8.00
3.00
0.38
1.00
0.50
0.25
0.75
0.25
N/A
0.13
0.25
0.13
0.25
0.25
0.25
2.00
0.25
1.00
TS g
4300
2900
281
184
433
336
262
307
N/A
59
139
40
336
150
291
748
353
N/A
MS g
196
136
15
10
28
25
20
25
N/A
6
13
4
29
17
26
75
28
N/A
Pb
40.7
27.0
69.7
70.7
48.0
105.0
N/A
N/A
N/A
143.0
204.0
316.0
228.0
116.0
208.0
N/A
N/A
N/A
rug/ kg
Cd
6.6
4.8
10.6
8.5
14.1
14.4
N/A
N/A
N/A
16.1
8.2
0.0
15.4
14.1
8.3
N/A
N/A
N/A
dry wt.
Zn
193
112
266
341
176
340
N/A
N/A
N/A
448
400
775
716
390
387
N/A
N/A
N/A
Hg
0.12
0.10
0.02
0.46
0.00
0.30
N/A
N/A
N/A
0.48
0.41
1.22
0.40
0.00
0.60
N/A
N/A
N/A
-------
o
CO
-------
function of river mileage occurs resulting in the lowest heavy metal sediment
concentrations being observed at the Stutson Street location.
The data in Figure 76 imply that the CSO's and stormwater discharges are
responsible for the heavy metal concentrations in the lower reaches of the
Genesee River. This is further supported by the analysis presented in Figure
77, which presents the sediment lead concentrations at the Kodak upstream site
as a function the number of days having greater than 0.25 in. of precipita-
tion. The sediment lead concentrations correlated reasonably well to total
precipitation measured during the sampling period. However, the latter part
of August and the first part of September are generally characterized by a
large number of low-intensity rainfall events, which contribute little to run-
off and therefore little to CSO's. An improved level of correlation was,
therefore, observed when a comparison was made between the total number of
days having greater than 0.25 in. of precipitation against the lead concentra-
tions measured at the Kodak upstream site.
It was found that the uncontaminated sediment, represented by the
Elmwood site, urban runoff contaminated sediment, represented by the Kodak up-
stream site, and CSO generated solids exhibited volatile solid concentration
ratios which were consistent with expected results. These ratios are pre-
sented as follows:
= 4-23xl°
-4
(Pb/Twc)
TVS 'CONTAMINATED
SEDIMENT
= 2.05x10
-4
= 2.62x10
-5
SEDIMENT
Figure 78 presents the average and range of the sedimentation rate data
for each of the Genesee River sediment monitoring sites. Table 57 presents
the laboratory established sediment oxygen uptake in g 02/m^/d.
TABLE 57. OXYGEN UPTAKE OF BOTTOM SEDIMENTS IN THE LABORATORY
Location
Site
Oxygen Consumption
g
Elmwood
Kodak (upstream)
Kodak (downstream)
Boxart
Stutson
1
5
2
3
4
0.15
0.08
0.23
0.05
0.09
193
-------
•uo.Lq.Bq.LdLD9wid 'SA suoiq.BJ^uaouoo
q.uauHpa$ •
Pb Concentration {mg/kg)
O
o
8
o
Ol
o
o
CJI
c_
>
o> •& ro
Total Precipitation (inches) '—'—'—L
01 ro —
TJ o ci -a o
S h» 3 ? 5
2. "* 2. o' **
TS =• » Q.^
3: 2 -» -r S
o §. HO •*
=•• « 5 < co
o en o 5- a
3 o =5 3
-* T5
O
S
o
1
Days Per Sampling
Period Having Greater
Than 0.25 inches
Precipitation
-------
ua
c
oo
CO
n>
O-
n>
3
CU
rt-
O
3
O
-5
n>
Q.
fD
3
Ct
3
O
O
-S
3
id
<-*•
n>
(0
00
8
1
1200-
1100-
1000-
900-
-§ 800-
CJ
^ 700-
o>
| 600-
c
•| 500-
1 40°
•5
0)
W 300
200
100
0
™
•o
E
UJ
•
'a.
o
•o
o
5(
bi
1
^-.
o
S
1 (
1 •
>e
B m
)3
)4
12 l'l 10 9 8 7 6 5 4 3 2
0
Sampling Location-Miles from mouth of Genesee River
-------
Sediment oxygen demand (SOD) tests were conducted on the Milwaukee River
during a recent CSO study (32). The results indicated that a significant
difference between SOD rates for disturbed and undisturbed conditions, such
as these conducted under bench scale testing, can exist. In that study, dis-
turbed SOD readings exceeded undisturbed laboratory readings by as much as a
factor of 1000. SOD values of nearly 1400 g 02/m2/d resulted from scouring
of bottom sediments which occurred from submerged CSO's. The report con-
eluded that high SOD readings can have a severe impact on the DO balance of
the Milwaukee River.
Because of the small magnitude of the SOD determined under the Rochester
BMP program would likely have little effect on the DO balance in the lower
reaches of the Genesee River under average flow conditions. The effect would
be much larger for oxygen demanding pollutants discharged into the River
during storm events from CSO and stormwater outlets.
RECEIVING WATER INVESTIGATIONS
Previous Studies
Systematic sampling of water quality conditions in the Genesee River
were conducted as early as 1912. These included:
1. A 1912 study conducted by George C. Whipple (33).
2. A 1929 study of the lower five mi of the Genesee River prepared
for the Eastman Kodak Company (34).
3. A 1929 study of the lower 10 miles of the Genesee River prepared
for the City of Rochester (35).
4. A series of 1954,sanitary surveys of the Genesee River conducted by
the New York State Department of Health to facilitate establishment
of water quality standards (36).
5. Data from ongoing New York State Department of Environmental con-
servation monitoring programs initiated in 1966 (37).
6. Data from ongoing monitoring programs on the Genesee River con-
ducted since 1965 by the Monroe County Health Department (38).
7. A series of summer river surveys conducted in 1973 on the Genesee
River as part of a study of water pollution problems in the Great
Lakes (39).
Although the historical data satisfactorily documented past water quali-
ty in the Genesee River, it was not adequate with respect to spatial detail.
Most of the surveys lacked CSO and stormwater discharge information required
to properly assess water quality. Therefore, four extensive water quality
surveys of the Genesee River were performed during 1975, two of which were
conducted during storm events (40). The results from these and earlier river
196
-------
surveys were used to develop, calibrate, and verify a water quality model of
the Genesee River.
In general, Genesee River water quality data obtained since 1973 indica-
ted that water quality was not generally stressed during dry-weather flows.
The levelof carbonaceous BOD was less than 10 mg/1 and the nitrogenous de-
mand was usually less than 5 mg/1. Contravention of the DO standard of 5.0
mq/1 occasinally occurred during dry-weather, during low river flow and high
amb ent ?em£erature conditions. The DO standard under these conditions was
marginally violated in the lower reaches of the river. Fecal coliform con-
centrat ons during dry-weather were generally not in violation of standards,
although some data indicated that severe short-term violations occurred as a
result of many point source discharges in the basin.
During wet-weather events the Genesee River experienced measurable water
quality degradation. Carbonaceous BOD concentrations above 40 ing/1 were ob-
served and nitrogenous BOD often exceeded 25 mg/1. The resulting DO concen-
trations were below 2 mg/1. Fecal coliform concentrations were also high
and of?enexceeded 100,000 cells/100 ml. This contravention.of standards was
though to result from stormwater and CSO discharges to the river.
General
The intent of the receiving water studies conducted as part of the over-
all Rochester BMP program was three-fold:
To determine the present impact of CSO discharges on the quality of
the Genesee River and Lake Ontario
To provide a continuous assessment of implemented control strate-
gies as developed under the BMP program
To determine the improvement of receiving water quality upon imple-
mentation of potential structurally-intensive abatement alterna-
tives-
The resulting product of the three phase program was to be utilized by the
Monroe County Pure Waters Agency for feedback and control of its overall
operations with its ultimate objective of protecting the receiving waters.
Under the BMP program, long-term monitors and associated data analyses
were intended to provide a better understanding of the nature of.receiving_
water impacts of CSO's through a correlation of transient precipitation epi-
sodes and water quality trends with rainfall and overflow occurrences from
the various drainage basins.
In addition to the long-term water quality monitoring of the Genesee
River, an analysis of long-term continuous time series data of receiving
water quality records was conducted. Currently, the Monroe County Department
of Health obtains water samples from the Genesee River on an hourly basis
during the months of May to September. An important parameter measured is
fecal coliform bacteria, because of its impact on the beaches. As part of
the BMP program, the data base acquired by agencies such as the Health Depart-
197
-------
ment was examined in an attempt to develop a relationship between fecal coli-
form counts and CSO discharges.
Design of Field Program
One of the primary objectives of the receiving water investigations was
to establish a continuous water quality monitor on the Genesee River. The
configured system was to measure the following parameters and store the re-
sults on a cassette tape for subsequent data reduction and analysis:
Temperature
Dissolved oxygen
Conductivity
Turbidity (percent light transmission)
The instrument selected for field installation was an automatic water quality
analyzer, Model Mark VIII, manufactured by Martek Instruments, Inc. This
system comprised a single electronic module. Internal subsystems allowed
interfacing to a remote sensor package, sensor signal conditioning, cassette
tape data recording, and digital displaying of parameteric data in engineer-
ing units.
Power to the system was provided by an external 12 VDC source with a
trickle charger, which maintained the battery at full capacity. A self-
contained power switching unit activated the sensors and signal conditioning
electronics only during programmed data recording intervals. This facilita-
ted monitoring operations during any extended periods of AC power outage.
Included in the total system package were a data reader and computer
interface. The data reader provided a visual display of the recorded data
from magnetic tapes and provided a suitable signal, with the aid of the
interface, for an external data processor.
Site Selection--
Previous Genesee River water quality modeling investigations have indi-
cated that maximum DO depressions as a result of CSO discharges occur in the
lower reaches of the river near Lake Ontario. This reach is known for low
velocities and even flow reversals due to the influence of the lake (40).
Based on these conditions, the water quality monitor was installed on the
Stutson Street Bridge. Figure 79 shows the location of the water quality
monitoring installation.
The recording unit to the monitoring system which was housed in a steel
shed located on a wooden pier below the bridge. The monitoring unit con-
taining the various measurement probes was located in approximately 15 ft of
water directly off the eastern bridge pier. AC power was available from the
control house located on the bridge. The necessary power lines were install-
ed and provided the monitoring system with full time recording capability
without the constant need to recharge or replace batteries.
198
-------
N
LAKE ONTARIO
Model Projected
Maximum D.O.
Depression From
CSO Discharges
Water Quality
Monitor
All CSOs
Occur Between
Figure 79. Water quality monitor location.
199
-------
Some initial start-up problems were encountered with the equipment,
which delayed water quality data recording. The system operated satisfactor-
ily from October 1979 through August 1980.
Results-
Data collected during 1979 proved to be of little value in assessing the
water quality of the Genesee River for several reasons. First, there were
occasional periods of equipment malfunctions. Second, during late fall, rain-
fall in the Rochester area becomes less intense but of a longer duration.
The result are storms that do not generate large volumes of CSO. This fact,
coupled with the generally higher river flows and cooler ambient temperatures
made it difficult to determine the impact of CSO discharges on the DO levels
in the river. Maximum DO depressions in the Genesee River were most likely
to occur during the summer, because of higher temperatures and low river
f1ows.
The main data collection period was, thus, the spring, summer, and
early fall of 1980. A thorough review of measured data for 1980 indicated
that on five occasions a DO depression followed a large storm event. The
exact magnitude of the DO depression was difficult to accurately determine,
but it was estimated that depressions in the range of 2.0 mg/1 occurred and
lasted over a period of 2 days. A definitive analytical relationship could
not be established between urban runoff and DO levels in the Genesee River.
Work by Others
An intensive Genesee River water quality monitoring program is conducted
annually by the Monroe County Health Department (MCHD) during the summer
months. A daily (Monday through Friday) grab sample is obtained from eight
locations along the River, as identified in Figure 80, from May through
August. Measured parameters include temperature, turbidity, BOD, and DO.
Except for the RG&E Headgates and the Stutson Street locations, all sampling
locations are upstream of the major CSO's from the City of Rochester.
The impacts that CSO's have on the water quality of the Genesee River
were partially established by the MCHD data base. Using fecal coliform (FC)
as an indicator, Figure 81 presents the FC levels measured at the Stutson
Street location for the period 25 June 80 through 26 August 80. Also plotted
were the total daily rainfall volumes for the same period.
The correlation between rainfall and FC levels was quite apparent.
During this period there were six days that the U.S. Weather Bureau reported
at least 0.50 in. of rainfall. The effect, although not immediate because
of time-of travel in the river, was seen at the Stutson Street location by
high recorded FC levels.
The large daily rainfall amounts on these six days resulted in CSO dis-
charges to the Genesee River. Volume of CSO discharged during any one storm
event ranged from 8 to more than 27 MG. Although the data base was limited,
there appeared to be no definitive analytical relationship between total
200
-------
Sampling Location
Figure 80. Monroe County Health Department river sampling stations.
201
-------
CAILT RfllNF&U. AT AJRPOHT - INCHES
9
l
2 W
V
I 1 I — 1— i
o
o <|
< o
o <•
.. 2
O -I
O -
o
o
O'
00
O--
o -
0::g
Figure 81. Fecal coliform concentrations in the Genesee River as
measured by Monroe County Health Department.
202
-------
overflow volume and FC levels in the river; however, a causal relationship
was evident.
Indications were that the FC loads entering the river must result from
CSO d "charges as illustrated in Figure 81. Measurements taken at the up-
stream sampling stations, prior to the CSOs, indicated that high levels of
FC bacteria were not present upstream of the city. DO measurements taken
at the same sampling locations indicated that CSO's affect the lower reaches
of the Genesee Rive?, but a quantitative cause and effect relationship could
not be established.
Fecal coliform levels in the lower reaches of the Genesee River near
Lake Ontario are an important consideration in water quality improvements
efforts be ng made by the BMP and other pollution abatement programs in the
CouSty of Ntonroe The MCHD continually monitors FC levels to insure safe
contact recreational use of these waters. Public bathing beaches along the
shore of Lake Ontario in the vicinity of the Genesee River are an important
asset to the community. The MCHD has the authority to close the beaches
depending on actual FC levels measured.
Table 58 presents the number of beach closing days for a five year
period.
TABLE 58. BEACH CLOSING DAYS*
Year
Days Open
Days Closed
% Open
1976
1977
1978
1979
1980
62
58
73
72
68.5
23
18
4
6
4
73
76
94
92
94
* Note: Data supplied by the MCHD
charges and FC levels in the river.
Genesee River Water Quality Modeling
The following discussion presents the water quality modeling framework
utilized to evaluate CSO impact on the Genesee River and to determine any
imjrovemen? in water quality as a result of implementation of the identified
BMP measures.
203
-------
The modeling framework used for the simulation and analysis of Genesee
River water quality was the LIMNO/SS. This mathematical model was a modifi-
cation of the steady-state AUTO-QUAL Modeling System (40). It is a one-
dimensional, second-order finite difference mathematical description of the
river, using a series of completely mixed batch reactions to simulate the
existing conditions of plug flow with dispersion. The structure of the model
was based on the continuity equation and included terms for advection, dis-
persion, and reaction. The relationship can be described by the equation:
dc. = E d c. - dc. + R
dt1 dx?1 H3T1
where,
c = concentration of parameter i
t = time
x = distance
U = velocity
R = reaction terms and other sources or sinks of parameter i
E = dispersion.
The model was used to simulate and project conditions of carbonaceous and
nitrogenous BOD, DO and FC in the Genesee River.
A prototype storm event occurring on November 10, 1975 was utilized to
prepare a series of sensitivity curves relating various maximum storm induced
water quality parameters in the Genesee River as a percentage of loading re-
presented by the prototype storm event. The prototype event involved a
total rainfall of 0.38 in. which occurred over a span of 8 hr with a maximum
hourly intensity of 0.22 in., as recorded at the Monroe U.S. Weather Bureau.
The rainfall hyetograph for this event is presented as Figure 82. The
maximum rate of CSO discharge was estimated at 154.4 cfs (99.7 mgd) during
the wet-weather event.
The input data set utilized to project the receiving water quality under
wet-weather conditions included the principal CSO's, stormwater discharges,
and steady-state discharges as presented in Table 59. These maximum dis-
charge rates, when modeled in a steady-state framework, represented the maxi-
mum receiving water impact associated with the specific event.
204
-------
STORM INTENSITY (INCHES/HOUR)
ho
o
en
to
c
n>
oo
fa
3
-h
n>
r+
O
-s
O)
TD
-s
o
-a
CD
n>
<
fD
§ §
8
-
O
f i
O
Ol
I
p
8
P
2
m
^ o
u>
8
ft
8
w
o
o
-------
TABLE 59. TREATMENT PLANT AND COMBINED SEWER DISCHARGES AND
UPSTREAM CONDITIONS AS DEFINED FOR THE PROTOTYPE WET-WEATHER EVENT
Overflow Name
Brooks
Plymouth
Court
Central
Mill & Factory
Carthage
Lexington
West Side Trunk
Norton & Seth
Green
Maplewood
Merri 1 1
Kodak STP
Elmwood Rd. Br.
Site
18
17
26
25
16
22
8
9
21
7
-
-
—
River
Mile
10.27
10.20
8.10
7.53
7.34
6.04
5.92
5.92
5.50
4.92
4.50
4.90
11.20
Flow
(mgd)
10.1
3.0
1.4
8.9
14.7
30.0
21.3
6.3
2.5
1.6
21.6
29.8
316.5
CBOD
(mg/1)
210.0
279.0
99.0
79.5
282.0
585.0
267.0
237.0
183.0
150.0
57.6
32.0
4.7
NBOD
(mg/1 )
4.1
19.9
0.5
10.8
19.7
16.0
20.2
19.2
16.5
6.9
2.1
91.6
3.2
DO
(mg/1)
5.0
5.0
5.0
5.0
5.0
5.0
5.0
5.0
5.0
5.0
5.0
3.5
7.8
Col i form
(#/100 ml)
7.5 X 10$
8.0 X 10r
5.0 x 102
5.0 x 102
8.0 x 10c
11.0 x 10?
8.0 x 10?
6.0 x 10?
24.0 x 10°
j—
6.4 x 10%
0.21 x 10°
8
3000
The Genesee River FC and DO concentration profiles under both average
river flow and minimum average seven consecutive day flow over a ten year re-
turn period (MA7CD/10) are presented in Figures 83 through 86. The exhibits
present the water column constituent as a function of river mileage for
various percentage loadings of the prototype storm event.
Figures 83 and 84 indicate that the Genesee River water column fecal
coliform concentrations .are dependent on minimal CSO discharges. Under
average yearly river flow of 2000 cfs (1292 mgd) the CSO discharge rate of
154.4 cfs (99.7 mgd) resulted in a peak water column FC concentration of
approximately 20,000 colonies/100 ml. Under the MA7CD/10 river flow condi-
tion of 490 cfs (316.5 mgd) the CSO discharge rate of 154.4 cfs (99.7 mgd)
resulted in a peak water column FC concentration of approximately 150,000
colonies/100 ml.
The FC concentrations predicted within the Genesee River are most impor-
tant relative to the best usage of the contact and secondary contact recrea-
tional resources in the lower reaches of the river and along the Rochester
Embayment of Lake Ontario. Figure 87 presents the location of presently
utilized public beaches and boat dockage facilities within the impacted
area.
Figures 85 and 86 present the receiving water quality model projections
of the water column dissolved oxygen concentrations under wet-weather condi-
tions under the Genesee River average yearly flow and the MA7CD/10 flow
regime. The data indicated that under average river flow conditions at water
column temperatures of 20°C, a CSO discharge rate of 154.4 cfs (99.7 mgd)
will result in a reduction in the minimum DO concentration of approximately
206
-------
00
ao 7.
DISTANCE (MILES)
ao
10.5
6.0
ao
DISTANCE (MILES)
84.
207
-------
10.0-r
9.0 ••
8.0 -
5.0 4
1.5
3.0
43 6.0 7.5
DISTANCE (MILES)
9.0
i as
I2JO
Figure 85. Model calculation of Genesee River dissolved oxygen
in response to CSO loads under average yearly flow.
10.0 +
8.0
0.0
O.O
3.0
4.5 6.0 75
DISTANCE (MILES)
9.0
10.5
Figure 86. Model calculation of Genesee River dissolved oxygen in
response to CSO loads at Q7-10.
208
-------
Northwest Quodronl STP
ro
O
c
-s
CO
0 -•• 0
O r+ O
3- 3- 0>
fD — '• rt-
ISI 3 -J.
rt- 0
fD c+ 3
-s 3-
fD O
fD -h
~-f 1
0-30
o> -a co
<< CD o
3 o
fD c+ Q.
3 fD -"•
rl- Q. to
n
o o 3-
-h -S Q>
fD -S
1 — CU id
CO fD
7T O tO
fD ~~h
O)
O r+ 3
3 3- 0-
<-t- (t>
Cu -S
-S fD fD
-"• fD O
O 3 -S
• fD fD
l/l OJ
fD rt-
fD -"•
0
PO 3
Loi
ani
.
2.
3.
4.
5.
6.
^
I .
8.
9.
10.
11.
12.
13.
I
<
fD
-S
n
a> —'
3 -"•
Q. H-
fD
• (/)
Ontario
Beach
Location Legend for Significant CSO
and Stormwater Discharges
Lake Ontario
Frank E. Vanlare STP
Irondequoit H. St. Paul STP
Merrill St. storm sewer
Eastman Kodak
Maplewood CSO
Norton P SethGreen CSO
Lexington CSO
West Side Trunk CSO
Carthage CSO
Mill & Factory
Central CSO
Court CSO
Plymouth CSO
Brooks CSO
13
Webster
VillageN
STP
Webster
Town STP
Irondequoit
Northeast STP
"^X^ Location
Of Boat Docking
Facilities
\2
fD
-------
3.0 mg/1. This represented a steady-state discharge worst case receiving
water condition for the given CSO discharge rate. The projected steady-state
DO concentrations associated with other discharge rates are also presented.
A plot of various system discharge rates under critical flow conditions
and water column temperatures of 20°C are presented in Figure 88. A close
analysis of the data indicated that a CSO system discharge rate in excess of
approximately 25 cfs (16.2 mgd) will result in a contravention of the 4.0 mg/1
DO standard. That is, there is very little available assimilative capacity
within the Genesee River. The possibility of a simultaneous major CSO dis-
charge and critical low flow river conditions, however, is remote.
Water Quality Modeling Impact Analysis--
Utilizing identified benefits of the regulator modifications and the
model projected benefits of both interceptor and control system modifications,
it was possible to project the relative improvement in various receiving
water quality parameters for a particular prototype storm event. CSO dis-
charge rates, pollutant loads, and SOD data obtained under the BMP program
were input to the previously calibrated water quality model to generate the
necessary projections. The storm of November 10, 1975, as described in the
preceeding subsection, was selected for this purpose. There are a large
number of rainfall events which exceed the total precipitation and intensity
of the prototype storm. The prototype storm was selected because it allowed
a reasonably sensitive comparison of the various collection system control
options.
Figures 89 and 90 present the projected minimum DO and maximum FC con-
centrations in the Genesee River associated with the application of the
various system control options to the prototype storm event under conditions
of average river flow. The control option measures evaluated with regard to
the attendant water quality response included:
No System Modifications (baseline condition)
Regulator Modifications (as implemented under the BMP program)
Interceptor and Associated Regulator Modifications
Control System Implementation
Rehabilitation of East Side Trunk Sewer
Combination of All Recommended System Control Options
The minimum DO concentration projected for the baseline condition repre-
senting the collection system without any improvement was approximately 5.8
mg/1 for the prototype storm event under conditions of average Genesee River
flow. The DO projected for application of all the recommended system Control
optio-ns (interceptor and regulator modifications, control system implementa-
tion, and rehabilitation of the East Side Trunk Sewer) under the same set of
conditions was approximately 7.8 mg/1. The effectiveness of each individual
component can be assessed by comparing the predicted DO concentration against
the baseline condition.
210
-------
O
O
8
ro
LJ
O
X
O
CO
O
O
CM
o
o
o
00
q
1/601«oa
q
t'
q
cvi
q
o
Figure 88. Critical dissolved oxygen concentrations vs.
magnitude of CSO loading.
211
-------
•MOU J9AU 96EJ9AB J.O SUOL^LpUOO U9pim
3.U9A9 uuoq.s edA~q.oq.oud sift oq. suoiq.do ui9q.sA~s [oaq-iioo
'siOLJBA J.O UOLq.EOLI.ddB 9L)q Lj^LM p9q.BLOOSSB U9ALy 99S9U90
9L)q. UL uoj.q.Buq.u90UOO UUOJ.LLOD [V3BJ. uinuiLXBiu
•68
Maximum Fecal Coliform Concentration (Log #/100 ml)
o
O t-,
CL. •yo -3
-*• ro c+
-htQ fD
-"• C D) -5
O —» 3 O
Cu O> Q- ft)
r*- r+ -D
-"• O r+
O -5 O
=5 -5
VI
D. 73
_.. ft)
-hea
-<• c
o —i
Oi Cu
O -S
in
O ^
Q. O
~j»
-h GO
_i.t<
n to
a> tt-
t-l- fD
§3
in
O
fi O
3 =5
T3 rt-
fD O
ft>
3 00.
O> 1/1
(-+ c-l-
--. fD
O 3
ro
3 rt-
~S
OO
-I
O 73 3
O fD a>
= o ch
O ->•
3 O
ID
3-
QJ
O cr
-h -••
m -'•
00 rt
—I 0>
oo c+
O
3
O
3
' fD
3 O
CL -h
ro
CL
-------
q.uaAa uuoq.s
.o uoi4BOL|.ddB aqq. L)
UL uoiq-Buq-uaouoD ua6/Cxo
j.o suoi4L.puoo uapun
oq. suoi^do [o^uoo aiaq.sA"s
LM paq.BpossB aaAiy aasauag
paALOSSip iuniuj.uj.tu paq.oa.Coud
•06
Dissolved Oxygen Concentration (mg/1)
CO CiJ -fc> CJI 0> --J CD
4
o
3
to
o. ro
-1.1Q
-h C
o' D)
B> pf
n- o
-O -5
—> O
fD —'
n> t>o
3 «<
r-t- in
BJ r+
r+ CD
o3
n>
U2
C l-i
— ' 3
Oi c+
H- fD
o -s
-5 n
fD
3-0
O rt-
Q. O
->• -S
n
o
3
-------
The baseline condition relative to the predicted fecal coliform concen-
tration in the Genesee River under the influence of the prototype storm event
is approximately 30,000 colonies/100 ml. Upon implementation of all recom-
mended control system options, the receiving water predicted fecal coliform
concentration is expected to be reduced to approximately 1,000 colonies/100
ml.
Dynamic water quality modeling was required to arrive at appropriate
receiving water quality responses to the evaluated abatement measures how-
ever, the resources were not available under the BMP study to allow for
development of dynamic, multiple event water quality simulators. Attempts
were made, however, to simulate as accurately as possible the receiving water
response under a specific set of receiving water and conveyance system"con-
ditions. Under a different set of selected conditions, the predicted re-
sponse could be substantially different. Most significant overflow events do
not coincide with average flow conditions at maximum receiving water column
temperatures.
It is also important to understand that the predicted FC and DO concen-
trations were for a single point in time and at a single point in a specific
receiving water transect.
BMP Program Phosphorus Reduction
Utilization of SSM modeling for assessing the reduction of overflow by
implementing the BMP measures resulted in projections of annual overflow
volumes from each of the overflow sites. By multiplying the annual overflow
volume at each site by the TIP concentration at each site, a projection of
annual TIP load to the Genesee River was determined for both the existing and
BMP improved systems. Since none of the BMP measures consist of treatment
per se (with the exception of the split-flow operations at the Van Lare
treatment plant), it was assumed that the reduction in TIP load was propor-
tional to the reduction in overflow at each site. The following presents
the loading reductions as a result of BMP implementation.
Site No.
7 Maplewood
10 Lexington
11 WSTS
17 Spencer
21 Mill &
Factory
27 Seth Green
31 Carthage
36 Central
Mean TIP
Cone.
mg/1
1.21
0.95
Existing BMP-System Existing TIP BMP TIP
Annual Over- Annual Over- Loading Loading
flow, MG flow, MG Ibs Ibs
.33
.28
.01
.22
.32
0.78
84
73
588
62
129
174
144
186
79
39
309
32
106
69
90
80
850
580
11,430
660
1,090
1,770
2,790
1,210
800
310
,000
340
890
700
,740
520
Total
1,670
990
23,120
13,520
214
-------
As indicated in the above tabulation, an estimated 41.5 percent reduc-
tion in TIP loading to the Genesee River from CSO is projected to occur upon
implementation of the BMP measures. However, it must also be pointed out :
that the additional flow contained within the collection system as a result
of BMP improvements is transmitted to the Frank E. Van Lare treatment plant
for processing. A certain fraction of the additional TIP transmitted to
Van Lare will be discharged in the plant effluent. It is therefore neces-
sary to examine the performance of the Van Lare plant under the split-flow
mode of operation in order to assess the actual realized reduction of TIP
loadings as a result of BMP improvements.
For the period of split-flow operation utilizing partial chemical-
assisted primary settling treatment (February 18, 1979 through June 3, 1979)
TIP removals averaged approximately 65 percent, with an average plant
effluent concentration of 0.86 mg/1. Based on a retention in the conveyance
system of an additional 9600 Ibs/yr of TIP as a result of BMP implementation,
and an average removal efficiency of 65 percent at the Van Lare plant, an
overall reduction in wet weather phosphorus loading from CSO's to the
Genesee River and Embayment area of 6240 Ibs/yr, or 27 percent, can be
realized.
214a
-------
SECTION 9
BMP PROGRAM IMPLEMENTABILITY
COMBINATIONS OF BMP OPTIONS
Evaluation of various control measures investigated under the overall
BMP program indicated that a combination of management options - both source
control and collection system - were most effective in maximizing the use of
the existing system and minimizing the frequency and volume of CSO s. Source
control management options which appeared to be the most effective^measures
for pollution abatement were surface flow attenuation, stormwater inlet con-
trol, and porous pavement.
Effective collection system management options included a combination of
improved overflow regulators/weirs and minimal structural improvements to the
St. Paul Boulevard Interceptor (SPBI) to provide for optimized system control
and minimized CSO's.
ANTICIPATED CSO REDUCTIONS
Based on overflow monitoring conducted prior to and after implementa-
tion of the identified regulator/weir modifications, a measureable reduction
in the frequency and volume of CSO discharged to the Genesee River was
realized. System modeling further indicated that implementation of the iden-
tified SPBI improvements, selective trunk sewer rehabilitation, and installa-
tion of collection system control structures would reduce the average annual
CSO volume by 41%. For these same improvements, average annual CSO duration
would be reduced by 46%.
The effectiveness of the implemented and proposed BMP control measures
on CSO reduction for an individual storm event is directly related to the
magnitude and intensity of rainfall. The greater the rainfall intensity,
the less effective are the BMP control measure in reducing CSO's. Monitored
data and system modeling indicated that for storm events involving rainfall
volumes of greater than 0.5 in., the Rochester BMP measures would reduce
CSO volume by approximately 3%. Storms of this magnitude occur about 20
times per year in the Rochester area. Storms containing 0.5 in. or less of
rainfall occur, on the average, 66 times per year.
In any event, implementation of minimal structural BMP collection sys-
tem management options will result in CSO reductions only if the existing
collection and treatment system components are presently under-utilized. If
these systems are operating at their maximum capacities, then the identified
BMP solutions will not be applicable.
215
-------
Relative to source control measures such as porous pavement, inlet con-
trol, street sweeping, and sewer and catchbasin cleaning, the average annual
CSO percent reduction upon implementation of or increased such activities
cannot be readily determined. It is known, however, that implementation of
these source control measures will reduce the annual volume of CSO but the
magnitude of the reduction cannot be determined. Source control measures
such as selective use of porous pavement and installation of inlet control
devices can result in significant CSO reductions in certain problem areas.
Effectiveness can only be determined on a site-specific basis.
Although increasing the frequency of street sweeping operations can
possibly result in additional pollutant removal, increased costs are almost
proportional to the percent increase in sweeping frequency. That is, since
street sweeping operations are labor intensive, increasing the street sweep-
ing frequency by a factor of two, for example, will result in an incremental
cost increase of approximately 100%. An analytical relationship between
pound of pollutant removed and number of passes and frequency of sweeping
has not been established. From the Rochester BMP study, however, the mar-
ginal increase in pollutant removed was small for doubling and tripling the
frequency of street sweeping operations. Therefore, because of the large
marginal cost to marginal benefit ratio, increased street sweeping activities
was not considered a viable, effective pollution control method. A similar
relationship exists for increased catchbasin cleaning activities.
The use of porous pavement is one source control management option that
appears to be a cost-effective solution to reducing the rate of stormwater
in selected areas. If the soil permeability conditions are adequate, thereby
eliminating the need for an underdrain system, costs for porous pavement are
comparable to those for conventional asphaltic pavements. The Rochester BMP
study evaluated the use of porous pavement under parking lot applications.
Results indicated that such pavements can adequately support the imposed
structural loads while maintaining a high rate of water infiltration. Extra-
polation of the use of porous pavements to other areas such as roadways
should not be made. Site-specific investigations should be conducted to
evaluate the use of porous pavements in applications other than for parking
lots.
If increased surface ponding can be tolerated, then implementation of
inlet control concepts can be an effective method of reducing CSO's. By
keeping stormwater out of the collection system or by limiting its inflow to
an acceptable rate, increased downstream flowrates can be minimized. The
costs involved in installing inlet control devices, such as Hydro-Brakes,
are small, however, the effectiveness of these devices has been shown only
for small problem areas. The feasibility of their use for large urban areas
must be more fully evaluated on a site-specific basis.. In any event, addi-
tional surface ponding will result from the installation of inlet control
devices, and therefore, the impacts of increased flooding must also be fully
evaluated.
216
-------
COSTS AND FINANCING
The Rochester BMP program involved the implementation of various minimal
structural control measures along with the installation of necessary overflow
and water quality monitoring to evaluate their effectiveness. Tables 60 and
61 present a summary of the costs associated with various aspects of the
overall study.
TABLE 60. PROGRAM ELEMENT COSTS
Element
Cost*
Upgrading existing CSO Sites
Water quality monitoring system
Upgrading of existing PDP-8E
computer system
Regulator/Weir modifications
Hydro-Brake Regulator
In-system monitoring site
Maintaining all monitoring systems
$5000/site
$15,000
$18,000
$l,500/site
$10,000
$7,000/site
$700/wk
Note: These costs include acquisition of the necessary
equipment and manpower to implement all instrumen-
tation. Costs for computer upgrading includes
development of necessary software.
TABLE 61. BMP SYSTEM IMPROVEMENT COSTS
System Improvement
Cost (mil $)
SPBI Improvements
ESTS Rehabilitation
Control Structures
Total
11.0
6.0
3.5
20.5
Note: These costs are total project costs in mid-1982
dollars and include items such as engineering,
legal and miscellaneous (29).
The method of financing such projects is expected to be consistent with
past practices by the County of Monroe. The legal and administrative proce-
dures required to obtain the necessary funding (local share) for the program
are summarized as follows (2):
217
-------
1. The Facility Plan is submitted to the Rochester Pure Waters Admin-
istrative Board for their approval and adoption as a basis for fu-
ture District improvements.
2. When the decision is made to proceed with the projects, and when
eligibility for state and federal aid is obtained, plans and speci-
fications are prepared for each project based on the Facility Plan
data for submission to the County Legislature and the New York
State Department of Audit and Control to obtain authority for the
sale of bonds.
3. The County Legislature refers the plans and specifications and re-
commendations to the Public Works and Ways and Means Committees for
review and recommendation to the full Legislature.
4. Upon receipt of the recommendations of the Public Works and Ways
and Means Committees, the Legislature adopts a resolution calling
for a public hearing on the proposed project based on a notice pub-
lished in the official newspapers of the county not less than ten
nor more than twenty days before the day set therein for the hearing.
5. After consideration of the results of the public hearing the Legis-
lature adopts a preliminary resolution approving the proposed in-
crease and improvement of facilities subject to receiving the con-
sent of the New York State Department of Audit and Control.
6. The County Manager submits an application to the Department of
Audit and Control for the Comptroller's order of consent.
7. Upon receipt of the Comptroller's order of consent the Legislature,
on recommendation of the Ways and Means Committee, adopts a bond
resolution, which resolution is published in the official newspapers
of the County with twenty-day legal notice of estoppel. Upon expir-
ation of the estoppel period the District Administrative Board is
in position to authorize implementation of the program including
additional engineering as required.
SCHEDULE OF IMPLEMENTATION
The intent of the Rochester Best Management Practices Implementation Pro-
gram was not to show whether CSO's are responsible for impaired receiving
water quality degradation but rather to investigate the possibility of imple-
mentating various source and control management options to alleviate known
problems caused by periodic CSO discharges. As a result of the study, sever-
al minimal system management options were identified as cost-effective in re-
ducing the frequency and volume of CSO as determined on an annual basis.
These include the SPBI improvements, ESTS rehabilitation, and control struc-
tures. The identified measures are compatible with other ongoing abatement
programs and form an integral part of the overall Master Plan for Monroe
County (2).
218
-------
By the nature of a BMP oriented program, pollution abatement can serve
as a Phase 1 solution to the identified CSO problem that can be initiated
almost immediately while long-term design and construction of more structural-
ly intensive abatement alternatives are undertaken.
Those BMP measures demonstrated to be cost-effective also involve items
with varying schedules for implementation. By carefully configuring the
implementation of the most promising BMP alternatives, both short and long
range objectives can be met. Most importantly, however, is the establishment
of these objectives.
The short range objective is simply to minimize the frequency and volume
of CSO presently discharged to the Genesee River through the full implementa-
tion of minimal regulator and weir modifications as described herein. The
effect will be a reasonable reduction in CSO for the more frequent, less in-
tense storm events. Thus, these modifications will be most effective during
the spring and fall months because of the general rainfall patterns in
Rochester characteristic of these months.
A substantially larger reduction in CSO will be realized upon the imple-
mentation of interceptor improvements and the installation of various control
structures at selected locations. The effect will be seen over a wider range
of storm events than those associated with the minimal regulator/weir modifi-
cations. This forms the basis for the long-term objectives.
It should be realized that even after these minimal structural improve-
ments, CSO discharges to the Genesee River will still be substantial for the
more intense, less frequent storm events, such as those associated with the
summer months. The other ongoing pollution abatement programs address
basically these types of storm events (2). Implementation of the identified
effective BMP measures is critical to the timely reduction of CSO discharges
to the Genesee River. Work associated with these projects can proceed con-
currently with all other ongoing programs and, in fact, will complement the
other ongoing abatement programs. Figure 91 presents the schedule of imple-
mentation for the BMP measures and their relationship to other abatement
programs.
A brief clarification of the differences between BMP, minimal structural,
and structurally intensive abatement alternatives should be made. There are
no rigid criteria that determine into which of these categories a particular
management option falls. There are guidelines, however, which are easily
applied. In general, any source control measure identified previously in
Figure 2 is classified as a BMP option. Most collection system management
options, as previously shown, are generally termed minimal structural. That
is, they do not involve a large capital expenditure. Structural intensive
alternatives are generally those traditional measures that involve the
application of storage and treatment systems. For example, tunnels and
overflow treatment facilities would be considered structurally intensive.
In general these structural programs are more expensive than BMP programs,
however, pollution abatement resulting from these capital-intensive programs
is much greater.
219
-------
\/////\ BMP Minimal-Structural Modifications
Y/7,
ESTS Rehabilitation
\/////\ Control Structures
///////\ SPBI Improvements
Performance Evaluations
Y////////////////////////X cMfstrprnt
H 1 1 1 1 1 h- 1 1 ! 1— h
1979 1980 1981 1982 1983 1984 1985. ,1986 •_• 1987, 1988 1989
Figure 91. Relationship of BMP improvements to overall CSO
Abatement Master Plan for the Rochester Pure
Waters District.
220
-------
It is obvious that what is expensive to one municipality may not be that
expensive to another. Costs are totally relative and must be judged from a
particular point of view. Aside from legal and institutional constraints that
may prevent the full implementation of various BMP or more expensive abate-
ment measures, BMP alternatives are generally effective in pollution abate-
ment resulting from typical or average storm events for small capital expen-
ditures, whereas, structural alternatives are necessary to protect the re-
ceiving waters from CSO's resulting from less frequent, more intense storm
events.
It is important to remember that the overall effectiveness of a BMP
oriented abatement program is largely dependent on the characteristics of the
existing conveyance and treatment systems involved. If the existing sewer-
system is already fully utilized in all aspects, those BMP measures identi-
fied as minimal structural under the general heading of collection system
management become ineffective and, therefore, not recommended. In these in-
stances, source control management options may be more effective. The
effectiveness of source control management options will be realized over a
narrower range of storm events. That is CSO reductions will occur for only
those frequent, small intensity storms.
In terms of planning and engineering financial assistance minimal struc-
tural improvement projects for which USEPA Construction Grants monies were
applied for and received were noted. For all the BMP CSO abatement measures
discussed in this report, it is recommended that planning and engineering
assistance in the form of USEPA Step I, II, and III grants be applied for to
minimize the financial burden of such programs on the particular municipality
involved. The amounts of reimbursement available is 75% federal share and
12.5% state share of the eligible monies expended.
LEGAL AND INSTITUTIONAL CONSTRAINTS
During the course of conducting the BMP investigations it became appar-
ent that there were several source control management options, that would be
difficult, if not impossible, to implement. Improved and/or increased street
sweeping may be difficult to implement as a source control management option
because this operation is a function of the City of Rochester and not of the
Monroe County Division of Pure Waters. Often, recommendations made by one
governmental agency that affect a different governmental agency and political
authority are simply not readily implementable. Increased street sweeping as
a source control option would be difficult to implement because of this
effect.
The identified minimal collection system management options identifed
previously appear to be relatively easily implementable with no discernible
legal and institutional constraints associated with such improvements. In
general, source control management options associated with a BMP oriented
program are more difficult to implement than collection system management
options The degree of difficulty in the implementation of various control
measures depends on the municipality involved. The municipality must deter-
mine the relative acceptability and implementability of any BMP abatement
alternative.
221
-------
RELATIONSHIP TO OTHER ONGOING POLLUTION ABATEMENT PROGRAMS
As mentioned previously, the source and collection system management
options demonstrated to be cost-effective are completely compatible with
other ongoing pollution abatement programs. Most notable of the other con-
current programs is the West Side Tunnel Storage/Conveyance System (2). The
minimal structural improvements recommended in this report address only a
small number of the problems to be solved by the proposed tunnel program,
especially when evaluated on a storm event basis.
222
-------
REFERENCES
11 «+ ai rnmbined Sewer Overflow Abatement Program,
l' KeTter/SVork ^Ti&S? Ana,ysis. USEPA Project No.
Y005141, Final Report. 1981.
I. Lozier Engineers, Inc.. Seelye Stevenson Value
USEPA Report No. EPft 905/9-76-005. November- 1976.
4 Monroe County Department of Planning, Monroe County, New York. Personal
Communication. December 1980.
5. Senesee Finger Lakes Regional Planning Council. Personal Co«uni cation.
December 1980.
6. Slack
Health. 1969.
7 Monroe County Pure Waters Agency Resolution from Meeting. Monroe
County, New York. February 17, 1972.
Sewer Study. Monroe County
November 1973 -
Revised June 1974.
New York. November 1973.
University of Rochester. 1972.
Bannister T T and R.C. Bubeck. The Limnology of Irondequoit Bay,
Monroe Countyl'New York. University of Rochester. August 1976.
223
-------
12. Thorne, J., et al. The Irondequoit Creek System: A Drainage Basin
Before Sewerage Diversion. University of Rochester for National
Science Foundation. 1973.
13. Diment, W.D., R.C. Bubeck and B.L. Deck. Some Effects of De-Icing Salts
on Irondequoit Bay and Its Drainage Basin. In: Highway Research Record,
Washin to Research Board> National Academy of Engineering,
14. Rainfall Frequency Atlas of the United States, Technical Paper No. 40.
U.5. Department of Commerce. Washington, D.C. May 1961.
Run0ff-
16. Sartor, J.D. and 6.B. Boyd. Water Pollution Aspects of Street-Surface
Contaminants. USEPA Report No. EPA-R2-72-081. 1971.
17. Pitt, R.F. and G. Amy. Toxic Materials Analysis of Street Surface
Contaminants.
18' S^nG" et a1- Water Quality Management Planning for Urban Runoff
USEPA Report No. EPA-440/9-75-004. 1975. "unon.
19. Pitt, R. Demonstration of Nonpoint Pollution Abatement Through Improved
Street Cleaning Practices. USEPA Report No. EPA-600/2-79-161? 1979.
20. Lager, John A., William 6. Smith and George Tchobanoglous. Catchbasin
Technology Overview and Assessment. USEPA Report No. EPA-600/2-77-
051. May 1977.
21. The! en, Edmund, et al . Investigation of Porous Pavement for Urban Run-
off Control. USEPA Report No. 11034DUY 03/72. March 1972.
22. Urban, J.B., and Gburek, W.J. Porous Asphalt Experimental Site.
In: Proceeding, International Symposium on Urban Storm Runoff
University of Kentucky, Lexington, Kentucky. July 1980. pp.*81-88.
23. Murray, D.M. and F.W. Ernst. An Economic Analysis of the Environmental
Impact of Highway Deicing. USEPA Report No. EPA-600/2-76-1 05
May 1976.
24. Peck, Ralph B., Walter E. Hanson and Thomas H. Thomburn. Foundation
Engineering. John Wiley & Sons, Inc., New York, New York, 1974
pp. 40-42.
25. Monroe County Soils Survey. Soil Conservation Service, U.S. Department
of Agriculture and Cornell Univesrity Agricultural Experiment Station.
U.S. Government Pointing Office, 1973. pp. 50-59.
26. Theil, Paul E. High Level of Flood Protection at Low Cost. In-
Proceedings of International Public Works Congress, October 18, 1978 in
Boston. American Public Works Association. 1978.
224
-------
27. Poertner, H.B. Practices in Detention of Urban Stormwater Runoff.
American Public Works Association. NTIS No. PB 234 554. June 1974.
28. McFadyen, G. Director of Engineering, Denver Urban Renewal Authority.
Personal Communication. November, 1978.
29. O'Brien & Gere Engineers, Inc. St. Paul Boulevard Interceptor Improve-
ments, Step 1 Facilities Plan. Draft Report. Monroe County Division of
Pure Waters, Monroe County, New York. January 1981.
30. Pisano, W.C., J. Rhodes, and G. Aronson. Preliminary Engineering
Feasibility Study for the Control and Treatment of Combined Sewer Over-
flows to the Saginaw River. USEPA Grant No. S 005339, Final Report.
March 1980.
31. Velz, C.J. Applied Stream Sanitation. Wiley-Interscience, New York,
New York, 1970. pp. 162-178.
32. Meinholz, T.L., et al. Verification of the Water Quality Impacts of
Combined Sewer Overflow. USEPA Report No. EPA-6/2-79-155. December 1979.
33. Fisher, E.A., E. Kuichling and G.C. Whipple. Report on the Sewage
Disposal System of Rochester, New York. April 1913.
34. Metcalf & Eddy Engineers. Problem of Disposal of Industrial Wastes
from Kodak Park. December 1929.
35. Metcalf & Eddy Engineers. Report to Harold W. Baker, Commissioner of
Public Works, Upon Sewage Disposal Problem: Rochester, New York.
December 1929.
36. New York State Department of Health. Lower Genesee River Drainage
Basin. July 1955.
37. New York State Department of Environmental Conservation. Unpublished
Data from Water Quality Surveillance Network, 1968-1975.
38. Monroe County Health Department. A Report on the Stream Quality
Monitoring Program. October 1975.
39. Moffa, P.E., C.B. Murphy, D.A. MacArthur, Water Pollution Investigation:
Genesee River and Rochester Area. USEPA Report No. EPA-905/9-74-016.
January 1975.
40. Murphy, C.B. and G.J. Welter. Genesee River Water Quality Investiga=-
tions. A Joint Venture. April 1976.
41. Monroe County Department of Health, Monroe County, New York. Personal
Communication, September 1980.
225
-------
TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
1. REPORT NO. , 2-
EPA-905/ 9-81-002
4. TITLE AND SUBTITLE
Best Management Practices Implementation Rochester,
New York
7. AUTHORISI Cornelius B. Murphy, Jr., Ph.D., Dwight A.
MacArthur, P.E., David J. Carloe, P.E.,
Thrifts J Ouirm P.K anH .Tsmips V. . St-eT.Ta-rf
9. PERFORMING ORGANIZATION NAME AND ADDRESS
Monroe County Division of Pure Waters
65 Broad Street
Rochester, New York 14614
12. SPONSORING AGENCY NAME AND ADDRESS
Great Lakes National .Program .Office .... .......
U. S. Environmental Protection Agency
536 South Clark Street, Room 932
Chicago, Illinois 60605
5. REPORT DATE
Anril 1981
6. PERFORMING ORGANIZATION CODE
8. PERFORMING ORGANIZATION REPORT
10. PROGRAM ELEMENT NO.
A42B2A
11. CONTRACT/GRANT NO.
G005335
13. TYPE OF REPORT AND PERIOD COVEF
?inal Report Oct. 78 '-Nov. 6
14. SPONSORING AGENCY CODE
US EPA-GLNPO
15. SUPPLEMENTARY NOTES This report of the Rochester Best Management Practices Implement
Program is to investigate the possibility of implementating various source and cont
management OPtions to allewlafo Vn^T.^ prnM pmo ranged Tiy pg-r-inrHn T^fl rH qrVi-argq _
The Best Management Practices(BMPs) offered an attractive and feasible alternative
to the partial solution of stormwater runoff induced receiving water quality
impairment for the City of Rochester, New York. The configured BMP program
resulted in a maeasureable reduction in the frequency and volume of combined sewe:
overflow (CSO) discharged to the Genesee River. The study defined and outlined tl
effective BMP measures, advanced a methodology of approach, and established
preliminary cost/benefit relationships.
A program of source control and collection system management BMP concepts proved
effective in reducing the frequency and volume of CSO for storm events with
rainfall volumes of 0.25 in. or less. For intense storm events the identified
system improvements resulted in minimal CSO reductions.
17.
KEY WORDS AND DOCUMENT ANALYSIS
b.lDENTIFIERS/OPEN ENDED TERMS c. COSAT1 Field/GrO
DESCRIPTORS
Urban runoff
Storm events
Rain gauge
Organic loading
Hydro-flusher unit
Sewer flushing
Storm water runoff
Porous pavements
Water quality
Dry-weather flow
13. DISTRIBUTION STATEMENT
Document is available to the public through
the National Technical Information Service,
Springfield, VA 22161 .._
(This Rep<
None
20. SECURITY CLASS (Thispage)
?. A 6
22. PRICE
EPA Form 2220-1 {9-73}
226
------- |