United States
Environmental Protection
Agency
Office of
Toxic Substances
Washington DC 20460
EPA-E60/11-79-011
September 1979
Toxic Substances
Effect of
Phosphorus Control Options
on Lake Water Quality
r
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EPA-560/11-79-011
EFFECT OF PHOSPHORUS CONTROL OPTIONS
ON LAKE WATER QUALITY
FINAL REPORT
September, 1979
by
Marc W. Lorenzen
Contract Number 68-01-3961
Project Officer
Justine Welch
Environmental Protection Agency
Washington, D.C. 20460
Tetra Tech, Incorporated
3700 Mt. Diablo Boulevard
Lafayette, California 94549
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DISCLAIMER
This report has been reviewed by the Office of Toxic Substances,
U.S. Environmental Protection Agency, and approved for publication.
Approval does not signify that the contents necessarily reflect the
views and policies of the U.S. Environmental Protection Agency, nor
does mention of trade names or commercial products constitute endorse-
ment or recommendation for use.
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ACKNOWLEDGEMENTS
The author gratefully acknowledges the contributions of several
individuals in the production of this report. Joy Valentini, Mei-Chi
Hua and Valerie Colber provided excellent computer programming and
data management services. Justine Welch provided critical review and
helpful suggestions throughout the project. Don Porcella, Joseph
Shapiro and Marv All urn provided critical review and helpful suggestions
related to procedures and methods of analysis. These individuals
should be given credit for many good ideas but are in no way responsible
for any errors, ommissions or shortcomings of the final product.
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TABLE OF CONTENTS
Page
SUMMARY AND CONCLUSIONS xvii
SECTION I - INTRODUCTION 1-1
BACKGROUND 1-1
SCOPE AND OBJECTIVES . . . 1-1
SECTION II - NATIONAL EUTROPHICATION SURVEY DATA BASE II-l
BACKGROUND II-l
Morphometry 11-3
Physical and Chemical Characteristics II-3
Biological Characteristics II-4
Nutrient Loading Characteristics II-5
Nonpoint Source Nutrient Export II-7
DATA COMPILATION 11-8
DATA SCREENING 11-8
LAKE CHARACTERISTICS 11-19
Surface Area 11-19
Mean Depth 11-19
Volume 11-19
Residence Time . . 11-19
Phosphorus Loading 11-20
Phosphorus Retention 11-23
Median Phosphorus 11-23
Chlorophyll-a_ 11-24
Secchi Disc 11-25
Ch1orophyll-a_ versus Phosphorus 11-25
Chlorophyll-a_ versus Secchi Disc 11-46
Response Time 11-47
SECTION III - TECHNICAL APPROACH III-l
PHOSPHORUS LOADING III-l
NEW MEDIAN PHOSPHORUS CONCENTRATION III-l
-------
TABLE OF CONTENTS (Continued)
Page
NEW CHLOROPHYLL CONCENTRATIONS 111-4
NEW SECCHI DISC III-6
PRESENTATION OF RESULTS . III-8
SECTION IV - CONTROL OPTION 1 - DETERGENT PHOSPHORUS CONTROL . . IV-1
METHODS IV-1
RESULTS (all lakes) IV-2
RESULTS (lakes with municipal treatment plants) IV-9
SECTION V - CONTROL OPTION 2 - TERTIARY SEWAGE TREATMENT
(80% P REMOVAL) V-l
METHODS V-l
RESULTS (all lakes) V-5
RESULTS (lakes with municipal treatment plants) V-5
SECTION VI - CONTROL OPTION 3 - 20% NONPOINT SOURCE CONTROL. . . VI-1
METHODS VI-1
RESULTS VI-1
SECTION VII - CONTROL OPTION 4 - 40% NONPOINT SOURCE CONTROL . . VII-1
METHODS VII-1
RESULTS VII-1
SECTION VIII - CONTROL OPTION 5 - 60% NONPOINT SOURCE CONTROL. . VIII-1
METHODS VIII-1
RESULTS VIII-1
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TABLE OF CONTENTS (Continued)
Page
SECTION IX - CONTROL OPTION 6 - 20% NONPOINT SOURCE AND
80% MUNICIPAL CONTROL IX-1
METHODS IX-1
RESULTS IX-1
SECTION X - CONTROL OPTION 7 - 40% NONPOINT SOURCE AND
80% MUNICIPAL CONTROL X-l
METHODS X-l
RESULTS X-l
SECTION XI - CONTROL OPTION 8 - 60% NONPOINT SOURCE AND
80% MUNICIPAL CONTROL XI-1
METHODS XI-1
RESULTS XI-1
REFERENCES
APPENDIX A - NATIONAL EUTROPHICATION SURVEY DATA USED IN
EVALUATION OF PHOSPHORUS CONTROL OPTIONS
1972 THROUGH 1975
APPENDIX B-l - LAKE RESPONSE DATA - PHOSPHORUS CONTROL
OPTION 1 - DETERGENT PHOSPHORUS CONTROL
APPENDIX B-2 - LAKE RESPONSE DATA - PHOSPHORUS CONTROL
OPTION 2 - TERTIARY SEWAGE TREATMENT
APPENDIX B-3 - LAKE RESPONSE DATA - PHOSPHORUS CONTROL
OPTION 3 - 20% NONPOINT SOURCE REDUCTION
APPENDIX B-4 - LAKE RESPONSE DATA - PHOSPHORUS CONTROL
OPTION 4 - 40% NONPOINT SOURCE REDUCTION
APPENDIX B-5 - LAKE RESPONSE DATA - PHOSPHORUS CONTROL
OPTION 5 - 60% NONPOINT SOURCE REDUCTION
m
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TABLE OF CONTENTS (Continued)
APPENDIX B-6 - LAKE RESPONSE DATA - PHOSPHORUS CONTROL
OPTION 6 - TERTIARY SEWAGE TREATMENT PLUS
20% NONPOINT SOURCE REDUCTION
APPENDIX B-7 - LAKE RESPONSE DATA - PHOSPHORUS CONTROL
OPTION 7 - TERTIARY SEWAGE TREATMENT PLUS
40% NONPOINT SOURCE REDUCTION
APPENDIX B-8 - LAKE RESPONSE DATA - PHOSPHORUS CONTROL
OPTION 8 - TERTIARY SEWAGE TREATMENT PLUS
60% NONPOINT SOURCE REDUCTION
APPENDIX C - EVALUATION OF AVAILABLE PHOSPHORUS MODELS
iv
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LIST OF FIGURES
Page
Figure II-l
Figure II-2
Figure II-3
Figure II-4
Figure II-5
Figure II-6
Figure II-7
Figure II -8
Figure II-9
Figure 11-10
Figure 11-11
Figure 11-12
Figure 11-13
Figure 11-14
Figure 11-15
Figure 11-16
Figure 11-17
Number of Lakes Sampled During National
Eutrophication Survey
Location of Lakes Remaining in Data Base
After Screening (493 Lakes)
Distribution of Surface Area and Mean Depth . .
Distribution of Volume and Retention Time . . .
Distribution of Total Phosphorus Loading ....
Distribution of Influent Phosphorus Concentration
and Phosphorus Retention Coefficient
Distribution of Median In-Lake Phosphorus
Concentration
Distribution of Mean Chlorophyll-a
Distribution of Mean Secchi Disc •
Mean Chlorophyll-a versus Median Total
Phosphorus (493 Lakes)
Mean Chlorophyll -a vs Median Total
Phosphorus for 1972 and 1973 Data . . . . . . .
Mean Chlorophyll-a vs Median Total
Phosphorus for 1974 and 1975 Data
Geographical Regions Used to Group Lake Data . .
Mean Chlorophyll-a versus Median Total
Phosphorus for Lakes in Area 1
Mean Chi orophyll-a versus Median Total
Phosphorus for Lakes in Area 2
Mean Chlorophyll-a versus Median Total
Phosphorus for Lakes in Area 3
Mean Chi orophyll-a_ versus Median Total
Phosphorus for Lakes in Area 4
II-2
11-11
11-12
11-13
11-14
11-15
11-16
11-17
11-18
11-27
11-28
11-29
11-30
11-31
11-32
11-33
11-34
-------
LIST OF FIGURES (Continued)
Page
Figure 11-18 Mean Chlorophyll -a_ versus Median Total
Phosphorus for Lakes in Area 5 11-35
Figure 11-19 Mean Chiorophyll-a^ versus Median Total
Phosphorus for Lakes in Area 6 . . . 11-36
Figure 11-20- Mean Chi orophyll-a_ versus Median Total
Phosphorus for Lakes in Area 7 11-37
Figure 11-21 Maximum Chlorophyll-a versus Spring Surface
Total Phosphorus Concentration for Lakes
in Area 1 11-39
Figure 11-22 Maximum Chiorophyll-a_ versus Spring Surface
Total Phosphorus Concentration for Lakes
in Area 2 11-40
Figure 11-23 Maximum Chlorophyll-a^ versus Spring Surface
Total Phosphorus Concentration for Lakes
in Area 3 11-41
.Figure 11-24 Maximum Chlorophyll-^ versus Spring Surface
Total Phosphorus Concentration for Lakes
in Area 4 11-42
Figure 11-25 Maximum Chlorophyll-a versus Spring Surface
Total Phosphorus Concentration for Lakes
in Area 5 11-43
Figure 11-26 Maximum Chlorophyll-£ versus Spring Surface
Total Phosphorus Concentration for Lakes
in Area 6 11-44
Figure 11-27 Maximum Chlorophyll-a_ versus Spring Surface
Total Phosphorus Concentration for Lakes
in Area 7 11-45
Figure 11-28
Figure 11-29
Figure 11-30
Figure 11-31
Theoretical Relationship Between Secchi Disc
and Chlorophyll for Various Values of a . .
Mean Secchi Disc versus Mean Chi crop hyll-a^ .
Mean Secchi Disc versus Mean Chlorophyll-a .
Mean Secchi Disc versus Mean Chlorophyll-a .
11-48
11-49
11-50
11-51
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LIST OF FIGURES (Continued)
Figure 11-32 Cumulative Distribution of Lake Response
Page
Figure III-l
Figure 1 1 1-2
Figure IV-1
Figure IV-2
Figure IV-3
Figure IV-4
Figure V-l
Figure V-2
Figure V-3
Figure V-4
Figure V-5
Figure V-6
Figure V-7
Figure V-8
Times
Relationship Between Theoretical and
Measured Phosphorus Retention Coefficients • • •
Mean Chi orophyll-a_ versus Median Total Phosphorus
(493 Lakes) (Heavy line shows effect of
reducing phosphorus on chlorophyll-a)
Distribution of New and Old Phosphorus
Loading Rates, Option 1
Distribution of New and Old Median Phosphorus
Concentrations, Option 1
Distribution of New and Old Chlorophyll-a
Concentrations, Option 1
Distribution of New and Old Secchi Disc
Depths, Option 1
Distribution of Sewage Treatment Plant
Effluent Phosphorus Concentrations, Option 2 . .
Distribution of Sewage Treatment Plant
Effluent Phosphorus Concentrations, Option 2 . .
Distribution of Sewage Treatment Plant
Effluent Phosphorus Concentrations, Option 2 . .
Distribution of New and Old Phosphorus
Loading Rates, Option 2
Distribution of New and Old Median
Phosphorus Concentrations, Option 2
Distribution of New and Old Chlorophyll-a
Concentrations, Option 2
Distribution of New and Old Secchi Disc
Depths, Option 2
Distribution of New and Old Median
Phosphorus Concentrations (Lakes with
Municipal Treatment Plants). Ootion 2
11-53
III-5
III-7
IV-3
IV-4
IV-5
IV-6
V-2
V-3
V-4
V-6
V-7
V-8
V-9
V-l 3
vii
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LIST OF FIGURES (Continued)
Page
Figure VI-1 Distribution of New and Old Phosphorus
Loading Rates, Option 3 VI-2
Figure VI-2 Distribution of New and Old Median
Phosphorus Concentrations, Option 3 VI-3
Figure VI-3 Distribution of New and Old Mean
Chlorophyll-a_ Concentrations, Option 3 .... VI-4
Figure VI-4 Distribution of New and Old Mean Secchi
Disc Depths, Option 3 VI-5
Figure VI-5 Distribution of New and Old Median
Phosphorus Concentrations for Lakes in
Area 1, Option 3 VI-7
Figure VI-6 Distribution of New and Old Median
Phosphorus Concentrations for Lakes in
Area 2, Option 3 VI-8
Figure VI-7 Distribution of New and Old Median
Phosphorus Concentrations for Lakes in
Area 3, Option 3 VI-9
Figure VI-8 Distribution of New and Old Median
Phosphorus Concentrations for Lakes in
Area 4, Option 3 VI-10
Figure VI-9 Distribution of New and Old Median
Phosphorus Concentrations for Lakes in
Area 5, Option 3 VI-11
Figure VI-10 Distribution of New and Old Median
Phosphorus Concentrations for Lakes in
Area 6, Option 3 VI-12
Figure VI-11 Distribution of New and Old Median
Phosphorus Concentrations for Lakes in
Area 7, Option 3 VI-13
Figure VII-1 Distribution of New and Old Phosphorus
Loading Rates, Option 4 VII-2
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LIST OF FIGURES (Continued)
Page
Figure VII-2 Distribution of New and Old Median
Phosphorus Concentrations, Option 4 VII-3
Figure VII-3 Distribution of New and Old Mean
Chlorophyll-a Concentrations, Option 4 .... VII-4
Figure VII-4 Distribution of New and Old Mean Secchi
Disc Depths, Option 4 VII-5
Figure VII-5 Distribution of New and Old Median
Phosphorus Concentrations for Lakes
in Area 1, Option 4 VII-7
Figure VI1-6 Distribution of New and Old Median
Phosphorus Concentrations for Lakes
in Area 2, Option 4 VI1-8
Figure VII-7 Distribution of New and Old Median
Phosphorus Concentrations for Lakes
in Area 3, Option 4 VII-9
Figure VII-8 Distribution of New and Old Median
Phosphorus Concentrations for Lakes
in Area 4, Option 4 VII-10
Figure VII-9 Distribution of New and Old Median
Phosphorus Concentrations for Lakes
in Area 5, Option 4 VII-11
Figure VII-10 Distribution of New and Old Median
Phosphorus Concentrations for Lakes
in Area 6, Option 4 VII-12
Figure VII-11 Distribution of New and Old Median
Phosphorus Concentrations for Lakes
in Area 7, Option 4 VII-13
Figure VIII-1 Distribution of New and Old Phosphorus
Loading Rates, Option 5 VIII-2
Figure VIII-2 Distribution of New and Old Median
Phosphorus Concentrations, Option 5 VIII-3
IX
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LIST OF FIGURES (Continued)
Paqe
Distribution of New and Old Mean
Chlorophyll-a_ Concentrations, Option 5.
VIII-4
Figure VIII-3
Figure VIII-4 Distribution of New and Old Mean Secchi
Disc Depths, Option 5 VIII-5
Figure VIII-5 Distribution of New and Old Median
Phosphorus Concentrations for Lakes
in Area 1, Option 5 VIII-7
Figure VIII-6 Distribution of New and Old Median
Phosphorus Concentrations for Lakes
in Area 2, Option 5 VII1-8
Figure VIII-7 Distribution of New and Old Median
Phosphorus Concentrations for Lakes
in Area 3, Option 5 VIII-9
Figure VIII-8 Distribution of New and Old Median
Phosphorus Concentrations for Lakes
in Area 4, Option 5 VIII-10
Figure VIII-9 Distribution of New and Old Median
Phosphorus Concentrations for Lakes
in Area 5, Option 5 VIII-11
Figure VIII-10 Distribution of New and Old Median
Phosphorus Concentrations for Lakes
in Area 6, Option 5 VI11-12
Figure VIII-11 Distribution of New and Old Median
Phosphorus Concentrations for Lakes
in Area 7, Option 5 VIII-13
Figure IX-1 Distribution of New and Old
Phosphorus Loading Rates, Option 6 IX-2
Figure IX-2 Distribution of New and Old Median
Phosphorus Concentrations, Option 6 IX-4
Figure IX-3 Distribution of New and Old Mean
Chiorophyll-a Concentrations, Option 6. ... IX-5
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LIST OF FIGURES (Continued)
Page
Figure IX-4 Distribution of New and Old Mean Secchi
Disc Depths, Option 6 ............. IX-6
Figure IX-5 Distribution of New and Old Median .
Phosphorus Concentrations for Lakes
in Area 1, Option 6 ............. IX-7
Figure IX-6 Distribution of New and Old Median
Phosphorus Concentrations for Lakes
in Area 2, Option 6 ............. IX-8
Figure IX-7 Distribution of New and Old Median
Phosphorus Concentrations for Lakes
in Area 3. Option 6 ............. IX-9
Figure IX-8 Distribution of New and Old Median
Phosphorus Concentrations for Lakes
in Area 4, Option 6 ....... ...... IX-10
Figure IX-9 Distribution of New and Old Median
Phosphorus Concentrations for Lakes
in Area 5, Option 6 ............. IX-11
Figure IX-10 Distribution of New and Old Median
Phosphorus Concentrations for Lakes
in Area 6, Option 6 ............. IX-12
Figure IX-11 Distribution of New and Old Median
Phosphorus Concentrations for Lakes
in Area 7, Option 6 ............. IX-13
Figure X-l Distribution of New and Old Phosphorus
Loading Rates, Option 7 ............ X-2
Figure X-2 Distribution of New and Old Median
Phosphorus Concentrations, Option 7 ...... X-4
Figure X-3 Distribution of New and Old Mean
Chlorophyll-^ Concentrations, Option 7 .... X-5
Figure X-4 Distribution of New and Old Mean Secchi
Disc Depths, Option 7 ............. X-6
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LIST OF FIGURES (Continued)
Page
Figure X-5 Distribution of New and Old Median
Phosphorus Concentrations for Lakes
in Area 1, Option 7 . . . . X-7
Figure X-6 Distribution of New and Old Median
Phosphorus Concentrations for Lakes
in Area 2, Option 7 X-8
Figure X-7 Distribution of New and Old Median
Phosphorus Concentrations for Lakes
in Area 3, Option 7 X-9
Figure X-8 Distribution of New and Old Median
Phosphorus Concentrations for Lakes
in Area 4, Option 7 X-10
Figure X-9 Distribution of New and Old Median
Phosphorus Concentrations for Lakes
in Area 5, Option 7 X-ll
Figure X-10 Distribution of New and Old Median
Phosphorus Concentrations for Lakes
in Area 6, Option 7 X-12
Figure X-ll Distribution of New and Old Median
Phosphorus Concentrations for Lakes
in Area 7, Option 7 X-13
Figure XI-1 Distribution of New and Old Phosphorus
Loading Rates, Option 8 XI-2
Figure XI-2 Distribution of New and Old Median
Phosphorus Concentrations, Option 8 XI-4
Figure XI-3 Distribution of New and Old Mean
Chlorophyll-a Concentrations, Option 8 XI-5
Figure XI-4 Distribution of New and Old Mean Secchi
Disc Depths, Option 8 XI-6
Figure XI-5 Distribution of New and Old Median
Phosphorus Concentrations for Lakes
in Area 1, Option 8 XI-7
XII
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LIST OF FIGURES (Continued)
Page
Figure XI-6 Distribution of New and Old Median
Phosphorus Concentrations for Lakes
in Area 2, Option 8 XI-8
Figure XI-7 Distribution of New and Old Median
Phosphorus Concentrations for Lakes
in Area 3, Option 8 XI-9
Figure XI-8 Distribution of New and Old Median
Phosphorus Concentrations for Lakes
in Area 4, Option 8 XI-10
Figure XI-9 Distribution of New and Old Median
Phosphorus Concentrations for Lakes
in Area 5, Option 8 XI-11
Figure XI-10 Distribution of New and Old Median
Phosphorus Concentrations for Lakes
in Area 6, Option 8 XI-12
Figure XI-11 Distribution of New and Old Median
Phosphorus Concentrations for Lakes
in Area 7, Option 8 XI-13
xm
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LIST OF TABLES
Paqe
Table II-l Number of Lakes Not Meeting Each
Criterion 11-10
Table II-2 Relative Contribution of Phosphorus from
Different Sources (493 Lakes) . . 11-21
Table II-3 Relative Contribution of Phosphorus from
Different Sources (mean percent,
493 Lakes) 11-22
Table IV-1 Effect of Control Option 1 on In Situ Total
Phosphorus Concentrations IV-7
Table IV-2 Number and Fraction of Lakes with Median
Phosphorus Concentrations Less than
0.025 mg/1 IV-8
Table V-l Effect of Control Option 2 on In Situ Total
Phosphorus Concentrations V-10
Table V-2 Number and Fraction of Lakes with Median
Phosphorus Concentrations Less than
0.025 mg/1 V-10
Table V-3 Number of Lakes Surveyed and Number With
Municipal Sources V-12
Table VI-1 Effect of Control Option 3 on In Situ
Total Phosphorus Concentrations VI-14
Table VI-2 Number and Fraction of Lakes with Median
Phosphorus Concentrations Less than 0.025 mg/£ . . VI-14
Table VII-1 Effect of Control Option 4 on In Situ
Total Phosphorus Concentrations VII-14
Table VII-2 Number and Fraction of Lakes with Median
Phosphorus Concentrations Less than 0.025 mg/£ . . VII-14
Table VIII-1 Effect of Control Option 5 on In Situ
Total Phosphorus Concentrations VI11-14
Table VIII-2 Number and Fraction of Lakes with Median
Phosphorus Concentrations Less than 0.025 mg/£ . . VIII-14
xv
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LIST OF TABLES (Continued)
Page
Table IX-1 Effect of Control Option 6 on In Situ
Total Phosphorus Concentrations IX-14
Table IX-2 Number and Fraction of Lakes with Median
Phosphorus Concentrations Less than 0.025 mg/£ . . IX-14
Table X-l Effect of Control Option 7 on In Situ
Total Phosphorus Concentrations X-14
Table X-2 Number and Fraction of Lakes with Median
Phosphorus Concentrations Less than 0.025 mg/£ . . X-14
Table XI-1 Effect of Control Option 8 on In Situ
Total Phosphorus Concentrations XI-14
Table XI-2 Number and Fraction of Lakes with Median
Phosphorus Concentrations Less than 0.025 mg/A . . XI-14
xvi
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SUMMARY AND CONCLUSIONS
BACKGROUND
Data collected as part of the National Eutrophication Survey
(NES) were compiled and used to assess the consequences of eight
different possible phosphorus control policies (options). The purpose
of this analysis was to identify options that would have the most sig-
nificant impact on water quality of the nation's lakes. The original
data base included measurements made at over 800 lakes distributed
throughout the contiguous United States. Data used in the analysis
included phosphorus loading from different sources (municipal, indus-
trial, septic tank, tributary and nonpoint); phosphorus retention
coefficients; in-lake concentration of total phosphorus and chloro-
phyll -a_; and Secchi disc measurements. Physical characteristics of
each lake including mean depth, area, and volume were also used in
the analyses.
Prior to use of the data base for analysis of phosphorus control
options, a number of checks were performed to assure completeness,
reasonableness of values, and appropriateness for the analytical
techniques used. Lakes without morphometric data, phosphorus con-
centration data, phosphorus loading data, or measurements of Secchi
disc, chlorophyll-a_ or phosphorus retention were eliminated from the
data base. After screening, 493 individual lakes were retained.
Table 1 provides a summary of the lakes' characteristics. De-
tailed data for each lake are contained in Appendix A. Curves show-
ing the distribution of characteristic values among the lakes are
given in Section II.
xvn
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Table 1
SUMMARY OF LAKE CHARACTERISTICS (493 lakes)
Variable
2
Surface Area (km )
Mean Depth (m)
Volume (106m3)
Retention Time (yr)
Median Total Phosphorus (mg/Jl)
Secchi Disc (m)
Mean Chlorophyll-a^ (yg/£)
Phosphorus Loading
kg/yr
g/m /yr
Phosphorus Retention Coefficient
Minimum
0.1
0.5
0.1
0.001
0.004
0.1
0.5
204
0.03
0.002
Mean
44
9.2
639
1.7
0.084
1.7
17.3
159,513
10.6
0.458
Maximum
1,490
89
35,000
58.5
1.525
13.3
381
6,697,765
818
0.996
Standard
Deviation
110
9.7
2,510
5.9
0.15
1.5
29.5
486,648
45
0.260
X
<
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OPTIONS
The purpose of the project was to assess the impact of various
phosphorus control options on the trophic state of the nations lakes.
The available options consisted of reducing the input of phosphorus
from different sources by various amounts. The eight options which
were analyzed are listed below.
Option 1 Detergent phosphorus control
Option 2 Tertiary sewage treatment
Option 3 20% reduction in nonpoint sources
Option 4 40% reduction in nonpoint sources
Option 5 60% reduction in nonpoint sources
Option 6 Tertiary sewage treatment plus
20% reduction in nonpoint sources
Option 7 Tertiary sewage treatment plus
40% reduction in nonpoint sources
Option 8 Tertiary sewage treatment plus
60% reduction in nonpoint sources.
METHODS
The method used to project the effects of each phosphorus con-
trol option on lake trophic status consisted of five steps as follows:
1. Compute new total phosphorus loading in
accordance with option.
2. Compute new in-lake phosphorus concentration
with a mass balance model and measured retention
coefficient.
xx
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3. Compute new chlorophyll-a_ concentration
from predicted phosphorus level.
4. Compute new Secchi Disc depth from new
chlorophyll-a_ concentration and light
attenuation coefficients.
5. Present results as figures and tables.
The detailed procedures used in each step are described in
Section III.
Before analyzing specific phosphorus control options the NES
data were reviewed to test the assumptions of common projection
techniques. The results of this review showed that several common
assumptions were not appropriate and projection techniques were
modified accordingly.
Phosphorus Retention
Recent literature (Lee, et_ aj_., 1978; Larsen and Mercier, 1975)
has indicated that phosphorus retention coefficients could be pre-
dicted from other variables (morphometry and flow rate). However, a
comparison of measured and predicted retention coefficients was found
to yield a very poor correlation as shown in Figure 1. As a result it
was decided to use observed retention coefficients based on influent
and effluent phosphorus concentrations for this study. It is realized
that these retention coefficients are subject to measurement error and
also may change as a result of changed loads. However, the measured
value was judged to be the best available indicator of phosphorus
retention for each lake.
Phosphorus-Chlorophyl1 Relationship
As discussed in Section III, considerable effort was devoted to
establishing a usable relationship between total phosphorus and
xix
-------
R =
O
O
a.
2:
o
--
(Q/V) 2 +
Q = hydraulic outflow
V = lake volume
mass in - mass out
mass in
1.0-
K + *"* + ^*V**I* ** . 1. Vf f ^
MEASURED RETENTION COEFFICIENT (Rj
FIGURE 1, RELATIONSHIP BETWEEN THEORETICAL AND
MEASURED PHOSPHORUS RETENTION COEFFICIENTS
XXI
-------
chlorophyll-a levels. It was found that a simple regression equa-
tion was not supported by the NES data. An alternative method was
developed that requires phosphorus to be reduced below a certain
limiting level (1 yg P = 1 yg chl.-a) before available phosphorus
would limit algal production.
Chlorophyll-a - Transparency
In order to predict the effects of chlorophyll-a_ on trans-
parency, a relationship between chlorophyll-a_ and Secchi isc depth
was needed. It was found that simple regressions were not adequate.
Most of the lakes apparently had considerable non-chlorophyll related
light attenuating characteristics. Consequently, a non-chlorophyll
light attenuation coefficient was computed for each lake and later
used in conjunction with predicted chlorophyll levels to compute
Secchi disc depths for each option.
RESULTS
The predicted total phosphorus concentration, chlorophyl l-a_
concentration, and Secchi disc depth for each lake for each option
are tabulated in Appendices B-l through B-8. The results are shown
graphically and by tabular summary in Sections IV through XI. As
part of the analysis the country was divided into seven areas as
shown in Figure 2. Table 2 summarizes the mean predicted total
phosphorus concentrations for all lakes within each region, for each
option tested. Table 3 summarizes the percent of lakes with median
total phosphorus concentrations less than 0.025 mg/£ for each region
and each option.
The following discussion summarizes the results of each option
analyzed. This summary is followed by a comparison of results and
conclusions.
xvi i
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X
X
FIGURE 2, GEOGRAPHICAL AREAS USED TO GROUP LAKE DATA
-------
Table 2
MEAN PREDICTED TOTAL PHOSPHORUS CONCENTRATION
FOR LAKES IN EACH AREA AND FOR EACH OPTION
X
X
Area
1
2
3
4
5
6
7
All
No.
of
Lakes
120
108
56
32
83
41
53
493
OPTION
No
Action
0.141
0.086
0.041
0.121
0.058
0.034
0.054
0.084
1
0.101
)
> 0.060
)
)
} 0.073
)
)
} 0.043
)
0.070
2
0.070
0.053
0.071
0.042
0.059
3
0.132
0.073
0.035
0.099
0.048
0.028
0.045
0.074
4
0.124
0.064
0.029
0.076
0.038
0.022
0.036
0.064
5
0.115
0.054
0.023
0.054
0.028
0.016
0.027
0.055
6
0.060
0.052
0.026
0.095
0.043
0.026
0.040
0.049
7
0.052
0.040
0.020
0.072
0.033
0.020
0.031
0.039
8
0.044
0.030
0.014
0.050
0.023
0.014
0.022
0.029
-------
Table 3
PERCENT OF LAKES IN EACH AREA WITH PREDICTED
TOTAL PHOSPHORUS CONCENTRATION LESS THAN 0.025 mg/£ FOR EACH OPTION
Area
1
2
3
4
5
6
7
All
No.
of
Lakes
120
108
56
32
83
41
53
493
PERCENT OF LAKES WITH TOTAL PHOSPHORUS LESS THAN 0.025 mg/A
OPTION
No
Action
30
27
41
9
29
49
45
32
1
32
(28)
33
(42)
(9)
23.5
(29)
(50)
48
(46)
33
2
42
(31)
36
(45)
(12)
27
(32)
(52)
50
(48)
38
3
36
31
45
12
35
59
51
37
4
40
37
52
16
46
68
57
44
5
48
45
68
28
59
80
72
55
6
48
36
54
13
43
59
53
44
7
54
44
68
16
57
68
62
53
8
64
59
88
31
73
83
77
68
X
X
-------
Options
Section IV presents the results of a ban on detergent phosphorus.
Two levels of control were considered. A complete ban was assumed to
result in a 45% reduction in municipal treatment plant phosphorus dis-
charges (Welch, 1979). A partial reduction was assumed to result in a
27% reduction in treatment plant phosphorus discharges. The results
indicate that this option would have very little effect on lake water
quality. Although 347 out of the total 493 lakes receive municipal
treatment plant effluent, only a small fraction of the total phosphorus
load is from municipal sources (^29%) and a 45% reduction would not be
expected to have a large effect on in-lake phosphorus concentrations.
The average concentration of total phosphorus for all lakes was predicted
to decrease from 0.084 mg/£ to 0.070 mg/i. Only four lakes (0.8%) were
projected to change from an average phosphorus concentration greater than
0.025 mg/£ to less than 0.025 mg/£. Projected chlorophyll-a_ concentra-
tions and Secchi disc depths were indistinguishable from old values.
Section V presents the results of imposing an 80% reduction on
municipal treatment plant phosphorus discharges. This was assumed
to approximate a nutrient removal requirement (tertiary treatment)
and was found to result in effluent phosphorus concentrations very
near 1.0 mg/JL The results indicated that for all 493 lakes the
average total phosphorus concentration would decrease from 0.084 mg/i
to 0.059 mg/a. For the 347 lakes which receive municipal effluent
the average phosphorus concentration was projected to decrease from
0.099 mg/H to 0.062 mg/£. The number of lakes with average total
phosphorus concentrations less than 0.025 mg/H was projected to in-
crease from 160 to 187 (27 lakes, 5.5%). Again, projected chlorophyll-a^
concentrations and Secchi disc depths were indistinguishable from old
values.
xxvi
-------
Sections VI, VII and VIII present the results of analysis for
nonpoint source phosphorus control. The contribution of rivers and
direct runoff was reduced by 20, 40, and 60%. The 20% reduction in
nonpoint sources projected a decrease in average total phosphorus
concentration from 0.084 mg/£ to 0.074 mg/Jl, roughly comparable to a
detergent ban. However, the number of lakes with average phosphorus
concentrations less than 0.025 mg/& was projected to increase from
160 to 183 (23 lakes, 4.6%) whereas the detergent ban resulted in the
same change for only four lakes. An analysis by geographical area
(see Figure 2) indicated some variation in the effectiveness of. non-
point source control. The Northwest showed the highest percent
improvement.
The 40% reduction in nonpoint sources projected a decrease in
average total phosphorus concentrations from 0.084 mg/& to 0.064 mg/£,
roughly comparable to tertiary sewage treatment (0.059 mg/£). However,
the number of lakes with average phosphorus concentrations less than
0.025 mg/H was projected to increase from 160 to 218 (58 lakes) whereas
tertiary sewage treatment resulted in the same change for only 27 lakes.
The effectiveness of a 40% reduction in nonpoint source phosphorus was
geographically quite uniform. From seven to 12 percent of the lakes
shifted below the 0.025 mg/Z guideline except in the Northwest (Area 6)
where 20% of the lakes shifted below the 0.025 mg/H criterion.
The 60% reduction in nonpoint sources projected a decrease in
average total phosphorus concentrations from 0.084 mg/£ to 0.055 mg/£,
again comparable to the tertiary sewage treatment option (0.059 mg/Jl).
However, the number of lakes with average phosphorus concentrations
less than 0.025 mg/£ was projected to increase from 160 to 273 (113
lakes) whereas tertiary sewage treatment resulted in the same change
for only 27 lakes. The effectiveness of the 60% nonpoint source con-
trol was found to be greatest in the western two-thirds and southeastern
part of the country. This reflects the fact that nonpoint sources
represented a larger fraction of the total phosphorus load in the
western and southeastern states.
xxvn
-------
Sections IX, X, and XI present the results of analysis for com-
binations of tertiary sewage treatment and nonpoint source control.
the results reflect an incremental improvement over the three non-
point source control cases. Tertiary sewage treatment plus 20% non-
point source phosphorus control results in an average in-lake phos-
phorus decrease from 0.084 mg/£ to 0.049 mg/£, somewhat better than
60% nonpoint source control. The number of lakes with an average
total phosphorus concentration less than 0.025 mg/£ was projected to
increase from 160 to 219 (59 lakes, 12%), considerably fewer than 60%
nonpoint source control (113 lakes). Regional differences were more
pronounced with East-Central and Southwest lakes being the least
improved in terms of the fraction of lakes with less than 0.025
mg/£ total phosphorus.
Tertiary sewage treatment plus 40% nonpoint source control
results in an average in-lake total phosphorus decrease from 0.084
mg/£ to 0.039 mg/£. Although this represents a considerable improve-
ment over the 60% nonpoint source control option (0.055 mg/£) the
number of lakes with average total phosphorus concentrations less than
0.025 mg/£ was projected to increase from 160 to 264 (104 lakes, 21%)
compared to 113 lakes for the 60% nonpoint source control alone.
The most stringent control option tested was tertiary sewage
treatment plus 60% nonpoint source control. It was considered un-
reasonable to expect that greater than 80% treatment plant removal
or greater than 60% nonpoint source control could be achieved. The
results project a decrease of average phosphorus concentration from
0.084 mg/£ to 0.029 mg/£. The number of lakes with a total phos-
phorus concentration less the 0.025 mg/fc was projected to increase
from 160 to 336 (176 lakes, 35.7%). This option would increase the
fraction of lakes with less than 0.025 mg/Jl total phosphorus from
32% to 68%.
xxvm
-------
Comparison and Conclusions
The results of the phosphorus control options analyses have
shown that, on a national scale, average lake phosphorus concentra-
tions could be reduced from 0.084 mg/jl to 0.029 mg/£ by a combina-
tion of municipal treatment plant and nonpoint source control.
Intermediate levels of improvement could be achieved with nonpoint
source control or municipal treatment plant control alone. It was
found that control of point sources was generally more effective
in reducing average phosphorus concentrations than it was in increas-
ing the number of lakes with median phosphorus levels below 0.025
mg/fc. For example, Option 5 (60% nonpoint source control) resulted
in approximately the same average phosphorus concentration for all
lakes (0.055 mg/&) as did 80% control of municipal treatment plant
phosphorus (0.059 mg/H). However, the 60% nonpoint source control
resulted in 55% (273) lakes having an average phosphorus concentra-
tion less than 0.025 mg/£ whereas 80% municipal control only resulted
in 38% (187) lakes having average phosphorus concentrations less than
0.025 mg/JL
The results varied somewhat by geographical area depending
primarily on the fraction of total loading from municipal versus
nonpoint sources. However, even in the Northeast where municipal
loads were the greatest fraction of the total, a 60% reduction in
nonpoint sources resulted in an average concentration of 0.115 mg/5,
and 48% (58 lakes) with less than 0.025 mg/£ average phosphorus con-
centration. The reduction of municipal phosphorus sources by 80%
resulted in a lower average phosphorus concentration (0.070 mg/£)
but fewer lakes (42% or 50 lakes) with median phosphorus levels
below 0.025 mg/A.
The study findings lead to the following conclusions:
xxix
-------
1. The degree of phosphorus enrichment of the -
nations lakes could be substantially reduced
by point and nonpoint source control measures.
2. The relative value of point versus nonpoint
control depends on the relative proportion of
loads.
3. Nonpoint source control results in a larger number
of lakes meeting an 0.025 mg/Jl phosphorus criteria
than does a similar reduction in point sources.
4. Although generalizations can be made about
regional and national lake quality, the most
effective control program must be designed for
each lake individually.
5. In general, industrial and septic tank
phosphorus sources are negligible.
6. The analysis indicates that chlorophyll-a_
levels and transparency (Secchi disc) would
be very insensitive to phosphorus reductions.
LIMITATIONS AND ASSUMPTIONS
Because the results of this study provide some broad general
findings which are based on a limited data set and may not be appli-
cable to any individual lake, it is important to understand some of
the limitations and assumptions of the study.
The objective of the study was to identify in broad terms the
effectiveness of different phosphorus controls, alone and in combi-
nation, on a nationwide basis. The large scope of the project limited
the study to the use of a large data base which required computer
manipulations. The National Eutrophication Survey was used because
it was the largest and most comprehensive system available, but it
also limited the study to the use of very simple models. More complex
models incorporating biological controls on dissolved oxygen and
xxx
-------
chlorophyll, or those using phosphorus released from the sediments,
could not be used because of lack of available data for a large number
of lakes. .
The National Eutrophication Survey data were extensive in terms
of the number of lakes sampled but limited in temporal and spatial
detail. It was beyond the scope of this project to assess the ade-
quacy of methods used to collect samples, conduct analyses or estimate
nutrient loading rates. In addition, it is possible that mean and
median values of the data collected may not be truly representative
of conditions in any one lake as a result of the limited number of
samples. However, the analysis assumed that reported values were
truly representative as these were the best available data.
The analytical approach to data analysis was also simplified and
in many cases conservative. Such factors as sediment phosphorus
release, zooplankton grazing, temperature, and nutrients other than
phorphorus were not considered. It was shown that phosphorus reten-
tion coefficients based on influent and effluent concentrations were
in poor agreement with theoretical values (see pp. III-3, -4, and -5).
The observed values were assumed to be correct and were used to pre-
dict the effects of changed loading rates.
The greatest uncertainty in the analysis is believed to be in the
prediction of chlorophyll-a (see pp. 111-5, -6). Previous researchers
have found good correlations between total phosphorus and chlorophyll-a_
levels. In this study neither median phosphorus and mean chlorophyll-a
nor spring phosphorus and maximum summer chlorophyll-a_ were correlated.
This lack of good relationship resulted in selection of a phosphorus-
chlorophyll relationship that is very conservative in terms of predic-
ting reduced chlorophyll or increased transparency. It is possible that
other relationships such as mean summer chlorophyll and mean summer
phosphorus might give a better relationship. However, it should be kept
xxxi
-------
in mind that there is great difference between examining many years of
chlorophyll-phosphorus data for one lake as compared to examining one
data point for each of many lakes.
The results of the study provide some general conclusions but
strongly indicate that the proper design and evaluation of a lake
restoration program must be on a case-by-case basis.
xxxn
-------
SECTION I
INTRODUCTION
BACKGROUND
Eutrophication of the nation's waters has been recognized as a
problem of increasing magnitude. One of the primary causes of
accelerated eutrophication is high loading rates of critical nutrients.
Phosphorus has been recognized as frequently not only the most impor-
tant nutrient but also the one most amenable to control. Recognizing
the need to control phosphorus as a potential environmental hazard
the U.S. Environmental Protection Agency has contracted with Tetra
Tech, Inc., to perform an analysis of the possible environmental
consequences of implementing various phosphorus control options.
The analysis is based on an evaluation of data collected
as part of the National Eutrophication Survey conducted by the U.S.
Environmental Protection Agency'for over 800 lakes between 1972
and 1975. These data include phosphorus loadings and in-lake concentra-
tions of phosphorus and chlorophyll-a_ as well as measurements of
transparency. The basic analyses conducted were to modify the loading
rates and compute the response of each lake.
SCOPE AND OBJECTIVES
This report documents the data base, the technical approach and
the results of options analysis.
Section II describes the National Eutrophication Survey data with
a general summary of the data to provide some guidance in understanding
the lakes' status and in selecting control options. Criteria used and
results of preliminary data base screening are described.
1-1
-------
Section III describes the technical approach and rationale for
procedures used in the evaluation of the effects of various control
options.
Sections IV through XI present the results of the analysis of
control options as listed below.
Option 1 Detergent phosphorus control
Option 2 Tertiary sewage treatment
Option 3 20% reduction in nonpoint sources
Option 4 40% reduction in nonpoint sources
Option 5 60% reduction in nonpoint sources
Option 6 Tertiary sewage treatment plus
20% reduction in nonpoint sources
Option 7 Tertiary sewage treatment plus
40% reduction in nonpoint sources
Option 8 Tertiary sewage treatment plus
60% reduction in nonpoint sources.
Appendix A provides listings of data for each lake.
Appendices B-l through B-8 provide the results of each option
for each lake.
Appendix C provides a review of phosphorus budget models.
1-2
-------
SECTION II
NATIONAL EUTROPHICATION SURVEY DATA BASE
BACKGROUND
The National Eutrophication Survey (NES) was initiated in 1972
by the U.S. Environmental Protection Agency (EPA) to investigate
the nationwide threat of accelerated eutrophication to freshwater
lakes and reservoirs. In conjunction with state environmental agencies,
the Survey developed information on nutrient sources, inputs, an9
impacts on selected freshwater lakes throughout the contiguous
United States. In total, over 800 lakes and reservoirs, 4,200 tribu-
taries and lake outlets, and 1,000 sewage treatment plants were
included in the sampling programs. The number of lakes sampled in
each state and the year surveyed are shown in Figure II-l. The joint
field effort involved EPA personnel, the National Guard of each
state, operators of municipal and industrial sewage treatment plants,
and personnel of the respective state agencies responsible for water
pollution control activities. For details of the procedures and
methods used, refer to NES Working Paper No. 1, "National Eutrophi-
cation Survey Methods for Lakes Sampled in 1972" and Working Paper
No. 175, "National Eutrophication Survey Methods for Lakes Sampled
in 1973-1975".
One of the primary outputs of the NES program is a set of reports in
which are summarized for each lake the trophic condition, nutrient sources,
loads, controllability and the limiting nutrient. Each report also in-
cludes all the NES data pertaining to the water body, the drainage area,
and the nutrient point sources. Data have been summarized and compiled
for water bodies sampled during each year of the Survey (NES Working Papers
Nos. 474, 475, 476, 477).
II-l
-------
12
10
/ 11
1 -
15
14
i
,4 \
3, 1
— 10 \
25
1975
11
78
46
11 r»oji
197;
30
15
16
a ,3 «1974
15
31 27
16
20
-13
16
39
16
18
J1973
5 11 \ 14
.13
41
FIGURE II-l NUMBER OF LAKES SAMPLED DURING
NATIONAL EUTROPHICATION SURVEY
-------
The compendium data base contains the following information as
described by EPA (1975b).
Mprphometry
The morphometric data were compiled from the literature and/or
from information provided by state and Federal personnel, and include:
LAKE TYPE--either of NATURAL origin or resulting from stream
IMPOUNDMENT.
DRAINAGE AREA (SQ KM)--the total drainage area, measured to the
lake outlet.
SURFACE AREA (SQ KM)--the area of the water surface.
MEAN DEPTH (METERS)--the volume of the water body, in cubic
meters, divided by the surface area in square meters.
TOTAL INFLOW (CMS)—the mean of the sums of the inflows of all
tributaries and the immediate drainage.
RETENTION TIME (YEARS or DAYS)--a mean value determined by
dividing the lake volume, in cubic meters, by the mean
annual outflow in cubic meters per unit of time.
Physical and Chemical Characteristics
These data are based on three samplings of each lake during the
ice-free period. For each lake, depending on its size, from one to
many sites were sampled, and multiple depths were sampled at each
site. For every parameter in this category, except Secchi disc depth,
the median value is reported. The median represents the middle value
of all sampling stations, times, and depths. The mean of the Secchi
disc depths at all stations and all sampling times are given.
II-3
-------
MEDIAN ALKALINITY (M6/L)—total alkalinity, as
MEDIAN CONDUCTIVITY (UMHOS)--specific conductance at 25°C.
MEAN SECCHI DISC (METERS)--the mean limit of visability of a
standard Secchi disc.
MEDIAN TOTAL PHOSPHORUS (M6/L)—as P.
As a separate task, the U.S. EPA also provided a listing
of spring surface total phosphorus concentrations.
MEDIAN DISSOLVED PHOSPHORUS (M6/L)—as P.
MEDIAN INORGANIC NITROGEN (MG/L)—nitrate + nitrite + ammonia,
as N.
MEDIAN TOTAL NITROGEN (MG/L)—Kjeldahl nitrogen + nitrate +
nitrite, as N (not determined in 1972).
Biological Characteristics
MEAN CHLOROPHYLL-A (yG/L)—the mean concentration of all samples.
Maximum chlorophyll-a^ values were also supplied as a
separate listing.
ALGAL ASSAY CONTROL YIELD (MG/L-DRY WT)~for the majority of
lakes is based on one value, in milligrams per liter dry
weight, obtained from an assay sample collected during the
last (fall) sampling. The test organism was Selenastrum
capyicornutum Printz.
LIMITING NUTRIENT (no units)--may be determined by two pro-
cedures which are (1) the growth response of Selenastrum
capricornutum to the addition of various amounts of
phosphorus or nitrogen or (2) the ratio or inorganic
nitrogen to dissolved phosphorus determined from the lake
II-4
-------
sampling data. When the weight ratio of inorganic nitrogei
to dissolved phosphorus is 14 to 1 or greater, the lake i ,
considered phosphorus limited, whereas ratios of less than
14 to 1 are considered indicative of nitrogen limitation.
It should be noted that these methods may not result in an
accurate estimate of what process or parameter actually
limits algal production in situ. For example, available
light may limit biomass when nutrients are present in excess.
SUMMARY OF PHYTOPLANKTON DATA--the COUNT of individuals, fila-
ments, or colonies per milliliter of sample for each of the
five most numerous genera are the data shown. The sum of
the units of other genera present in the sample, but not
specified, is also included.
Nutrient Loading Characteristics
Nutrient loads of significant tributaries and the lake outlet(s)
were calculated using the results of analyses of from 12 to 14 samples
collected from each stream by the state national guard monthly for a
one-year period and stream flow estimates as provided by the U.S.
Geological Survey through an interagency agreement. The nutrient loads
of the unsampled portion of the lake drainage areas were estimated from
the measured nutrient loads in the sampled streams in the area. Nutrient
loads of all streams and the unsampled drainage area were estimated on
the basis of a year of average or "normal" stream flow to minimize the
influence of extreme hyc'rological events that may have occurred during
the sampling year.
Sewage treatment plant nutrient loads were determined from results
of analyses of 12 monthly effluent samples and corresponding flow data
provided by plant operators or by state agency personnel. For sewage
II-5
-------
treatment plants which did not participate in the sampling program,
nutrient discharges were estimated on the basis of the population
served by the facility and estimated per capita nutrient production.
For details of sampling procedures and methods of calculation,
refer to NES Working Paper No. 1 and NES Working Paper No. 175.
INPUT (KG/YR)--an estimate of all external inputs of nitrogen
and phosphorus to the water body.
POINT SOURCE MUNICIPAL (K6/YR)—an estimate of annual nitrogen
and phosphorus inputs from municipal sewage treatment plants,
POINT SOURCE INDUSTRIAL (KG/YR)--an estimate of annual nitrogen
and phosphorus inputs from industrial waste treatment plants,
POINT SOURCE SEPTIC TANKS (KG/YR)—an estimate of annual nitrogen
and phosphorus inputs from septic tanks within approximately
100 yards of the lake shoreline.
NONPOINT SOURCE (KG/YR)—an estimate of the annual nitrogen and
phosphorus inputs from tributaries, immediate drainage, and
precipitation.
TOTAL LOADING (KG/YR)--the sum of all external nitrogen and
phosphorus inputs.
LAKE SURFACE AREA LOADING RATE (G/SQ M/YR)—the total loading
for the sampling year divided by the lake surface area
/kg/yr -m~3\
( *'fr x 10 ).
km
OUTPUT (KG/YR)--an estimate of the annual nitrogen and phosphorus
discharged through the lake OUTLET(S).
II-6
-------
PERCENT RETENTION--the percentage of incoming nitrogen or
phosphorus retained in the lake annually:
/Input load-output load -\r\r\y\
^ input load "'
Nonpoint Source Nutrient Export (Note: "Export" was used by EPA to
represent loading to the lake)
STREAM NAME--
MEAN FLOW (CMS)--the mean stream flow in a year of average hydrology.
DRAINAGE AREA (SQ KM)—the drainage basin area of the stream.
MEAN TOTAL P (MG/L)--the mean concentration of total phosphorus in
the stream at the sampling site during the year of sampling.
MEAN TOTAL N (MG/L)--the mean concentration of total nitrogen in
the stream at the sampling site during the year of sampling.
TOTAL P EXPORT (KG/SQ KM/YR)—the total phosphorus load of the
stream (after subtracting known point-source loads) divided by
the drainage area, in kilograms per square kilometer per year.
TOTAL N EXPORT (KG/SQ KM/YR)—the total nitrogen load of the stream
(after subtracting known point-source loads) divided by the
drainage area.
In addition to these data, average hydraulic flow rates for munici-
pal treatment plants were compiled and keypunched from individual lake
reports. These data were needed to compute treatment plant effluent
phosphorus concentrations.
It is beyond the scope of this study to describe and evaluate the
methods, analytical procedures and validity of the data base. The
reader is referred to the three NES Working Papers (Nos. 1, 175, and
All urn, ejt al_., 1977) for descriptions of methods, procedures and evalu-
tion of data.
II-7
-------
DATA COMPILATION
The first step in the preparation of the data base was to compile
data relevant to this study into tables and plots. For each lake the
following variables were tabulated:
Lake Characteristics
2
Surface Area, km
2
Drainage Area, km
Mean Depth, m
Volume, 106m3
Retention Time, years
Median Total Phosphorus Concentration, mg/1
Mean Secchi Disc, m
Mean Chlorophyll-a, ug/1
Phosphorus Loading (kg/yr, % of total) from:
Septic Tanks
Municipal Treatment Plants
Industrial Sources
Rivers
Direct Runoff
Precipitation
2
Total (kg/yr, g/m /year)
Measured Phosphorus Retention, fTpJr (decimal fraction)
DATA SCREENING
Prior to use of the data base for analysis of phosphorus control
options, a number of checks were performed to assure completeness and
reasonableness of values.
II-8
-------
In order for a lake to be included in the data base, data had to
be available for each of the following:
1. Mean depth
2. Volume
3. Hydraulic residence time
4. Median phosphorus concentration
5. Secchi disc depth
6. Mean chlorophyll-a
7. Total phosphorus loading
8. Measured phosphorus retention coefficient
In addition, lakes with a negative measured phosphorus retention
coefficient were rejected as not being amenable to the analytical
procedures used in this analysis (see Section III). Lake Tahoe was
also rejected because of its very long retention time (400 years)
which implies that the data are not representative of steady-state
conditions.
Table II-l shows the number of lakes not meeting each selection
criterion and the total number of lakes rejected from each year's sur-
vey. Figure II-2 shows the location of lakes remaining in the screened
data base.
Tables of all data subsequently used in analysis are provided in
Appendix A to this report. The distributions of selected parameter
values for all lakes used are illustrated in Figures II-3 through II-9.
These figures show the cumulative distributions of parameter values by
plotting the number of lakes with parameter values less than or equal to
the plotted value. Plots of parameter values by year surveyed (geo-
graphical area) are contained in Appendix A.
II-9
-------
Table II-l
Number of Lakes Not Meeting Each Criterion
Total Lakes
Reported
CRITERIA
1 . Mean Depth
2. Volume
3. Retention Time
4. Phosphorus -i
Concentration
5. Secchi Disc
6. Chlorophyll-^
7. Total P Loading1
8. Retention Coeff.
9. Neg. Ret. Coeff.2
10. Municipal^
Treatment Plant
Phosphorus
Concentration
>20 or
<1 .0 mg/1
Total Lakes Rejected:
Total Lakes Remaining:
Survey Year
1972
200
26
26
49
0
0
2
32
31
25
6
81
119
1973
206
3
3
12
0
0
0
6
11
24
4
41
165
1974
177
1
1
39
0
0
0
41
44
18
0
62
115
1975
153
4
4
32
0
1
1
31
35
19
2
59
94
1972-75
736
34
34
132
0
1
3
no
121
86
12
243
493
1. Lake omitted if data not available for this variable.
2. Lake omitted if measured phosphorus retention coefficient was negative.
3. Municipal treatment plant phosphorus concentrations <1.0 or >20 mg/1 are
thought to be outliers and these lakes were omitted.
11-10
-------
FIGURE II-2
LOCATION OF LAKES REMAINING IN DATA BASE
AFTER SCREENING (493 LAKES)
-------
NES DATA 1972-1975
500 n
400-
3
CO
s:
:=>
300
200-
100-
MINIMUM: 0.1 KM'
MEAN: 44.
MAXIMUM: 1,190
2
0.1
1.0
10 100
SURFACE AREA (SO K
1000
]0,000
'!00
300
200
100-
MINIMUM: 0.5M
MEAN: 9.2
MAXIMUM: 89
20
0- GO
MEAN DEPTH (M)
80
100
FIGURE II-3
DISTRIBUTION OF SURFACE AREA AND
MEAN DEPTH
11-12
-------
NES DATA 1972-1975
500 n
LiJ
3
400-
300-
«=c
o
200-
100-
0.1
100 -
MINIMUM: 1 x 105 M3
6.4 x 108
MAXIMUM: 3.5 x 1010
10 100 LOOO
VOLUME (106 METERS3)
10,000 100,000
300-
200
100-
MINIMUM: 0.001 YRS
MEAN: 1.75
MAXIMUM: 58
0.0001 0.001
FIGURE ll-H
0.01 0.1 1.0 10.0
RETENTION TIME (YEARS)
DISTRIBUTION OF VOLUME AND
RETENTION TIME
ion
11-13
-------
NES DATA 1972-1975
500 n
400-
3
o
SI 300.
CO
•a:
O
200-
100-
MINIMUM: 204 KG/YR
MEAN: 160 x 103
'MAXIMUM: 6,698x10'
1 x 102
1 x 103 1 x 10^ 1 x 105
TOTAL PHOSPHORUS LOADING (KG/YR)
1 x 106 1 x 107
500
400 -
o
£ 300 -J
200-
100-
MINIMUM: 0.03 G/MVYR
MEAN: 10.6
MAXIMUM: 817
0,01
0.1
1.0
10.0
100
1,000
TOTAL PHOSPHORUS LOADING (G/MVYR)
FIGURE 11-5 DISTRIBUTION OF TOTAL PHOSPHORUS
LOADING
11-14
-------
NES DATA 1972-1975
500i
400
Li-
en
55 300
CO
200-
100
MINIMUM: 0.01 MG/L
MEAN; 0.1
MAXIMUM: 10.0
r
0.01
0.1 1,0
ANNUAL AVERAGE INFLUENT PHOSPHORUS CONCENTRATION (MG/L)
SOO-i
400-
55 300 -
CO
200-
100-
0.0
MINIMUM: 0.002
MEAN: 0.458
MAXIMUM: 0.996
lo'.o
0,2 0,4 0,6 0,8
PHOSPHORUS RETENTION COEFFICIENT
1.0
FIGURE II-6
DISTRIBUTION OF INFLUENT PHOSPHORUS CONCENTRATION
AND PHOSPHORUS RETENTION COEFFICIENT
11-15
-------
NES DATA 1972-1975
500-
400'
3
o
£ 300-
CQ
200-
T
Indicates number of
lakes >1.0
MINIMUM: 0.004 MG/L
MEAN: 0.084
MAXIMUM: 1,5
100-
I VTrlJ... .„ ........ , _._.„._ . I I _-___!
0.2 0.4 0,6 0.8 1.0 >1.0
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (MG/L)
500 -,
CO
UJ
400-
97
r
Indicates number of
lakes >0.10
CD
£ 300.
CQ
200-
_r
100-
0.02 0.0'4 0.06 O.OS
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (MG/L)
OJO >0,10
FIGURE II-7
DISTRIBUTION OF MEDIAN IN-LAKE
PHOSPHORUS CONCENTRATION
11-16
-------
500-i
100-
3
£ 300
CQ
200
100-
400-
300.
200-
100-
NES DATA 1972-1975
MINIMUM: 0.5 yG/L
MEAN: 17.3
MAXIMUM: 381
20
60
30 100 > 100
MEAN CHLOROPHYLL-A ^G/L)
100
J
3.0 12.0 16.0
CHLOROPHYLL-A (/ 20.0
FIGURE 11-8 DISTRIBUTION OF MEAN CHLOROPHYLL-A
11-17
-------
500-
400-
co
LU
O
S 300-
200-
100
NES DATA 1972-1975
,-T
J
MINIMUM: 0.1'M
MEAN: 1,7
MAXIMUM: 13.3
r
i.o 2.0
3.0 . 4.0
SECCHI DISC (M)
5.0
6?0~~ >6.0
FIGURE II-9 DISTRIBUTION OF MEAN SECCHI Disc
11-18
-------
LAKE CHARACTERISTICS
The characteristics of the lakes in the data base are briefly dis-
cussed below. Special attention was given to examination of Figures II-3
through II-9 to determine if there were any logical groupings of lake
types that might emerge.
Surface Area
The mean surface area for all lakes contained in the final data base
is 44 square kilometers. The minimum is 0.10 square kilometers, and the
maximum is 1,490 square kilometers. Although the lakes do not fall into
distinct size classes, approximately 70% of the lakes have a surface area
between 5 and 100 square kilometers.
Mean Depth
The mean average depth for all lakes in the final data base is 9.2
meters. The minimum mean depth is 0.5 meters and the maximum is 89 meters,
Over 90% of the lakes have a mean depth less than 20 meters.
Volume
Lake volumes ranged from 0.1 x 10 to 35,039 x 10 cubic meters with
a mean value of 638 x 10 cubic meters. Approximately 70% of the lakes
c c
had volumes between 10 x 10 and 5,000 x 10 cubic meters.
Residence Time
The minimum hydraulic residence time was 0.001 year and the maximum
58 years. The mean for all lakes was 1.75 years. Approximately 70% of
the lakes had a hydraulic residence time between 0.1 and 5.0 years.
11-19
-------
Phosphorus Loading
The phosphorus loading rates are illustrated in terms of total
2
loading (kg/yr), surface loading (g/m /yr) and average influent con-
centration (mg/1). The range and mean values are shown below.
Minimum
Mean
Maximum
kg/yr
204
159,513
6,697,765
g/m2/yr
0.03
10.64
817
mg/1
0.01
0.1
10.0
Approximately 80% of the lakes had a total phosphorus loading rate
2
between 0.5 and 10.0 g/m /year.
The phosphorus loadings from different types of sources, including
municipal, septic tank, industrial, tributary rivers, direct runoff, and
precipitation are listed for each lake in Appendix A. Table II-2 lists
the statistics related to percent contribution for all lakes in the
screened data base. Table II-3 shows mean percent contributions of
various sources by geographical area.* These values clearly show region-
al differences in phosphorus sources. However, it should be noted that
the Northeast and North-Central Lakes are biased because the selection
process used for this region favored lakes with municipal treatment
plants. It is clear that so called "nonpoint" sources, rivers and direct
runoff, account for the majority of phosphorus loading. Municipal treat-
ment plants are significant, but represent a considerably smaller contri-
bution. In general, industrial and septic tank sources are negligible.
*Note: Year surveyed corresponds to geographical area as follows
(see Figure II-l):
1972
1973
1974
1975
Northeast and North-Central
East and Southeast
Central
West
11-20
-------
Table II-2
Relative Contribution of Phosphorus
from Different Sources (493 lakes)
Source
Municipal
Septic Tank
Industrial
Rivers
Direct Runoff
Precipitation
Number
of Lakes
347
114
24
484
452
321
Percent of Total P Loading
Min.
1
1
1
1
1
1
Mean
29
5
12
64
12
5
Max.
99
52
56
100
87
66
Mean*
20
1
0.6
63
11
3
NOTE: Mean = mean value for lakes with loading >_ 1% from
indicated source.
Mean* = mean value for all lakes (includes lakes with
< 1% loading).
Number of lakes is the number which have >_ 1% loading
from the indicated source.
11-21
-------
Table II-3
Relative Contribution of Phosphorus from Different Sources
(mean percent, 493 lakes)
Source
Municipal
Septic Tank
Industrial
Rivers
Direct Runoff
Precipitation
1972
North Central
& Northeast
38
2.4
1.1
45
8.6
5.1
1973
Southeast
22
1.3
0.5
64
10
1.9
1974
Central
12
0.3
0
69
15
3.6
1975
Western
7.0
0.5
0.9
76
12
3.6
11-22
-------
Phosphorus Retention
The phosphorus retention coefficient ranged from 0.002 to 0.996
with an average value of 0.458. The minimum, mean, maximum and standard
deviation of values observed in each geographical area are tabulated
below:
Phosphorus Retention Coefficient
Year
Surveyed
1972
1973
1974
1975
Min.
0.002
0.003
0.004
0.012
Mean
0.386
0.417
0.576
0.476
Max.
0.958
0.981
0.996
0.988
Standard
Deviation
0.245
0.229
0.260
0.283
Median Phosphorus
The median in situ total phosphorus concentration ranged from
0.004 mg/1 to 1.5 mg/1 with a mean value of 0.084 mg/1. Only 160 of
493 lakes (32%) had a median total phosphorus concentration less than
the 0.025 mg/1 recommended by the U.S. EPA (1974b). The minimum, mean,
maximum and standard deviation of values observed in each geographical
area are tabulated below along with the percent of lakes which had
median total phosphorus concentrations less than the recommended
0.025 mg/1.
11-23
-------
Median Phosphorus Concentration
Year
Surveyed
1972
1973
1974
1975
Min.
mg/1
0.004
0.006
0.010
0.006
Mean
mg/1
0.141
0.070
0.075
0.045
Max.
mg/1
1.525
0.865
0.489
0.371
Standard
Deviation
mg/1
0.258
0.099
0.084
0.054
%<0.025
32
33
24
48
Chlorophyll-a
Mean chlorophyll-a concentrations for all lakes averaged 17.3 yg/l.
The minimum was 0.5 yg/1 and the maximum 381 yg/1. Nine lakes had mean
chlorophyll-^ values greater than 100 yg/1 and 100 lakes had chlorophyll-a_
values greater than 20 yg/1. The distribution of values by geographical
area (year surveyed) is shown below.
Mean Chlorophyll-a Concentrations
Year
Surveyed
1972
1973
1974
1975
Min.
yg/l
1.0
1.2
1.5
0.5
Mean
yg/1
24.1
18.8
15.3
8.4
Max.
yg/l
381
221
100
72
Standard
Deviation
yg/l
44
29
15
8.4
11-24
-------
Secchi Disc
The mean Secchi disc depths ranged from 0.1 meter to 13.3 meters
with a mean value of 1.7 meters. Only ten lakes had a mean
Secchi disc depth greater than six meters. The distribution of
values by geographic region is shown below.
Mean Secchi Disc
Year
Surveyed
1972
1973
1974
1975
Win.
m
0.2
0.2
0.1
0.2
Mean
m
1.8
1.4
1.3
2.8
Max.
m
5.9
4.1
6.4
13.3
Standard
Deviation
m
1.2
0.9
1.0
2.5
Chlorophyll-a vs. Phosphorus
Numerous attempts have been made to relate chlorophyll-a_ to
phosphorus concentrations (Sakamoto, 1966; Lund, 1971; Dillon and
Rigler, 1975; Dillon, 1974). These studies found reasonably good
relationships of the form:
chl-a^ - 0.08 (P)1'5
where P = total phosphorus
(II-D
The U.S. EPA (1974b) used data from the 1972 NES survey to obtain the
2
following expression with an r of 0.61:
lo9lOPtotal = °'846
- 2'354
11-25
-------
This equation can be transformed to:
chl-a.= 0.172(P)1>18 (II-2)
Figure 11-10 shows the relationship between mean chlorophyll-^ and
median total phosphorus for all lakes with data. Equation 11-2 is also
shown. The line bounding these data has an initial slope very nearly
equal to 1,000 yg chl.-a per mg phosphorus (1 yg of phosphorus results
in 1 ug of chlorophyll-.a when nothing else limits production). Figures
11-11 and 11-12 illustrate subsets of the data by geographic region.
The relationships are essentially the same.
Because a relationship between chlorophyll-^ and phosphorus would
be very helpful in evaluating the effects of phosphorus control on lake
quality, additional effort was devoted to examining any potential re-
lationships.
The first step was to examine the data on a regional basis. The
493 lakes were separated into seven geographical areas as shown in
Figure 11-13. These areas were somewhat arbitrarily selected to see
if differences that might result from climate, geological or hydro-
logical conditions might become apparent. The mean chlorophyll-a_ was
then plotted against the median phosphorus concentration for each
lake within each area. The results are shown in Figures 11-14 through
11-20. No distinct regional differences were found. Additional sub-
classification of lakes into five groups within each area was also
examined. The five groups were: 1) mean depth £five meters, 2) mean
depth >five meters, 3) hydraulic detention time pne month but
-------
I
ro
100 n
,Chl a (ygA') = 1000 P(mg/V)
4-
00
0.00 0.05 0.10 0.15 0.20 0.25 0.30
MEDIAN TOTAL P, mg/i
0.35 0.40
FIGURE 11-10 MEAN CHLOROPHYLL-A VERSUS MEDIAN TOTAL PHOSPHORUS
(493 LAKES)
-------
a
o
.
a,
CO
_J
\o
.
03
H
Q_
D
cc:
3s
a
a
1972 LAKE DATA
Chl a_ (vig/1) = 1000 P (mg/1)
0,20 0.25 0.30
0.05 0.10 0,15
MEDIflN TOTflL P IHG/L)
0,35 0,40
o
o
1973 LAKE DATA
Chl a (yg/1) = 1000 P (mg/1)
0.05
FIGURE 11-11
0,10 0.15 0.20 0.25 0.30
NEDIflN TOTflL P IHG/L)
MEAN CHLOROPHYLL-^ vs MEDIAN TOTAL
PHOSPHORUS FOR 1972 AND 1973 DATA
0.35 0.40
11-28
-------
a
a
a
a>
No
cr
-"a
CL
a
a:
-la
1974 LAKE DATA
Chl a. (yg/1) = 1000 P (mg/1)
j
0.35 0.40
0.05 0.10 0.15 0.20 0.25
MEDIflN TOTRL P IHG/L)
0.30
a
a
a.
CO
_J
\o
Oa
=>o.
«-CD
-la
_Ja
3-
a.
a
tr
°a
—la
r
U
a.
w
a
a
1975 LAKE DATA
Chl a^ (yg/1) = 1000 P (mg/1)
/ JL4. -Jp" -Jfl. -
JP^
n I
.00 O.t
H- + +
i i I
15 0.10 0.15 0.20
hEDlflN TOTflL P
•H
1 1 1 1
0.25 0.30 0.35 0.40
IHG/L)
FIGURE 11-12
NEAN CHLOROPHYLL-A vs MEDIAN TOTAL
PHOSPHORUS FOR 1974 AND 1975 DATA
11-29
-------
CO
o
FIGURE 11-13 GEOGRAPHICAL AREAS USED TO GROUP LAKE DATA
-------
o
o
D
O
03
> <=•
< I •
I O.
Q_
O
o;
O O
o.
o
o
•
D.
«M
O
D
+
++
+ +
•f
++ + +
+
+ * +
& * 4
$f\#
V>++ +f +
0.05 0.10 0.15 0.20 0.25
MEDIAN TOTAL P, MG/L
0.30
0-35 0.40
FIGURE
MEAN CHLOROPHYLL-^ VERSUS MEDIAN TOTAL PHOSPHORUS
FOR LAKES IN AREA 1
11-31
-------
o
o
0
o
•
o.
O-
10
Q_
O
D.
(M
o
o
0.05 0.10 0-15 0.20 0.25
MEDIAN TOTAL P, MG/L
0.30 0.35 0.40
FIGURE 11-15
MEAN CHLOROPHYLL-A VERSUS MEDIAN TOTAL PHOSPHORUS
FOR LAKES IN AREA 2
11-32
-------
o
D
O
D
O_
CD
D
O
D.
10
Q_
O
a: O
3 O
5 o
O
o
I
o.
D
O
0.05 0.10
0.15 0.20 0-25
MEDIAN TOTAL P, MG/L
0-30
0.35
0.40
FIGURE 11-16
MEAN CHLOROPHYLL-A VERSUS MEDIAN TOTAL PHOSPHORUS
FOR LAKES IN AREA 3
11-33
-------
o
D
O
O
D
O
O
CD
Q_
O O
o
o
D.
CM
O
O
^.00 O.OS 0.10 0.15 0.20 0-25
MEDIAN TOTAL P, MG/L
0.30
0.35
0.40
FIGURE 11-17
MEAN CHLOROPHYLL-A VERSUS MEDIAN TOTAL PHOSPHORUS
FOR LAKES IN AREA 4
11-34
-------
o
o
o
o_
O
O
D
CD
O
o.
10
Q_
O
ct:
o o
—i o
C3_
o
o
+ ~S ++ * *
0.05 0.10
0.15 0.20 0-25
MEDIAN TOTAL P, MG/L
0-3D
0.35
0.40
FIGURE 11-18
MEAN CHLOROPHYLL-A VERSUS MEDIAN TOTAL PHOSPHORUS
FOR LAKES IN AREA 5
11-35
-------
o
o
o
D-,
0
O
GO
I O-
Q_
O
an
O O
o
o
o
CM
+ +
0-05 0-10
0-15 0.20 0-25
MEDIAN TOTAL P, MG/L
0.30 0.35 0.40
FIGURE 11-19 MEAN CHLOROPHYLL-^ VERSUS MEDIAN TOTAL PHOSPHORUS
FOR LAKES IN AREA 6
11-36
-------
D
O
O
D_
D
O
O.
00
Q_
CD
og
5 o
o
o
o
o
A
0.05 0.10 0-15 0.20 0.25
MEDIAN TOTAL P, MG/L
0-30
0.35
0.40
FIGURE 11-20
MEAN CHLOROPHYLL-A VERSUS MEDIAN TOTAL PHOSPHORUS
FOR LAKES IN AREA 7
11-37
-------
It is understood that the variables plotted (median total phosphorus
and mean chlorophyll-a_) may not be the most appropriate to find the type
of relationship desired. The U.S. EPA therefore suggested and provided
a listing of maximum measured chlorophyll-a_ values and surface spring
phosphorus concentrations. These data were plotted in the same manner
as used for median values and are shown by area in Figures 11-21 through
11-27. The further breakdown by lake characteristics is shown in Appendix
A. As expected, higher concentrations of chlorophyll-a_ as a function of
total phosphorus were found. However, the general pattern of the data
(wide scatter with many lakes having high phosphorus concentrations and
low chlorophyll values) was similar to when median concentrations were
used.
11-38
-------
D
O
O
D_
O
O
D.
(D
o
o
D.
CO
I?
=c o_
§ o
D
O
+ +•'
0.05 0.10 0.15 0.20 0.25 0-30
SPRING SURFACE MEAN TOTAL P, NG/L
0.35
0-40
FIGURE 11-21
MAXIMUM CHLOROPHYLL-A VERSUS SPRING SURFACE
TOTAL PHOSPHORUS CONCENTRATION FOR LAKES
IN AREA 1
11-39
-------
o
D
D
D-,
O
D
o.
CD
O
O
D.
IO
Q_
O
O
<_J O.
_ f
D
O
•
D.
-------
D
D
D
0-,
D
O
o.
ID
^ °
2- o
> t
?,' SJ
Q_
O
O i
X
<£.
D
O
•H-
o'.lO O'.IS o'.20 0'.25
SPRING SURFACE MEAN TOTAL P, MG/L
0-30
0.35
0.40
FIGURE 11-23
MAXIMUM CHLOROPHYLL-A VERSUS SPRING SURFACE
TOTAL PHOSPHORUS CONCENTRATION FOR LAKES
IN AREA 3
11-41
-------
D
D
D
O
O.
CD
Q_
O
O
;n
i_>
O-
(O
O
O
O
X
O-
N
V
0.05 0.10 0-15 0.20 0.25
SPRING SURFACE MEAN TOTAL P, MG/L
0-3D
0.35
0.40
FIGURE 11-24
MAXIMUM CHLOROPHYLL-A VERSUS SPRING SURFACE
TOTAL DHOSPH.ORUS CONCENTRATION FOR LAKES
IN AREA 4
n-42
-------
o
D
O
O
o.
03
<\ '
I O.
Q_
CD
O D
=! o
52
X
2 o
o
•
D.
W
0-05 0.10 0-15 0.2D 0-25 0-30
SPRING SURFACE MEAN TOTAL P, MG/L
0.35 0.40
FIGURE 11-25
MAXIMUM CHLOROPHYLL-A VERSUS SPRING SURFACE
TOTAL PHOSPHORUS CONCENTRATION FOR LAKES
IN AREA 5
11-43
-------
o
D
O
OL_
O
O
O.
07
0
O
Q_
CD
cr:
o
o_
o
o
•
o.
CJ
D
O
t*
0.05 0.10 0-15 0.20 0.25 0-30
SPRING SURFACE MEAN TOTAL P, MG/L
0.35
0.40
FIGURE 11-26
MAXIMUM CHLOROPHYLL-A VERSUS SPRING SURFACE
TOTAL PHOSPHORUS CONCENTRATION FOR LAKES
IN AREA 6 •
11-44
-------
o
D
D
O
O
07
o
o
•
D.
(£>
Q_
O
ct:
CD
O
D
D.
o
o
D.
OJ
D
O
-H-
+ * +
+ . +
0.05 0.10 0-15 0-20 0-25 0-30
SPRING SURFACE MEAN TOTAL P, MG/L
0.35
0-40
FIGURE 11-27
MAXIMUM'CHLOROPHYLL-A VERSUS SPRING SURFACE
TOTAL PHOSPHORUS CONCENTRATION FOR LAKES
IN AREA 7
11-45
-------
Chlorophyll-a vs Secchi Disc
It has been shown experimentally and theoretically (Lorenzen &
Mitchell, 1975) that light attenuation in a water column can be closely
approximated by an expression such as:
d = e-(a+30 d
o
where
I, = Illumination at depth, d
I = Surface illumination
a = Attenuation coefficient for color, turbidity, etc.
3 = Incremental attenuation coefficient for algae
C = Algal concentration
d = Depth
It has also been shown that Secchi disc depth can be closely
approximated by the depth to which 20% of surface visible light
penetrates (Lorenzen, 1978).
The Secchi disc depth can therefore be approximated by
Secchi disc = -1nj°ec20) (II-4)
At high algal concentrations (3C»a) the attenuation of light and
Secchi disc depth are controlled by the phytoplankton. However,
at low algal concentrations, the penetration of light is largely due
to light absorbing properties other than phytoplankton (a). Large
variations in Secchi disc depth at low chlorophyll concentrations.
are likely due to factors other than changes in chlorophyll concen-
tration.
11-46
-------
The extinction coefficient due to factors other than algae (a),
varies widely ranging from 0.04 m for distilled water (Clarke, 1954)
to 0.7 nf or more. The incremental extinction coefficient, $, has
been found to be fairly constant at approximately 0.2 m /mg/1 ash free
dry weight (Lorenzen, 1975). Unfortunately, the chlorophyll content
of algal cells is quite variable, so it is more difficult to relate
the attenuation coefficient to chlorophyll. For illustrative
purposes, Figure 11-28 was constructed for various values of a (0.04
to 1.0 m ) and 3 = .030 m /mg/1 chl.-a. Figure 11-29 shows a similar
plot of NES data for all years surveyed. Data from each year are
shown in Figures 11-30 and 11-31. A comparison of these plots with
Figure 11-28 shows that most lakes had non-chlorophyll attenuation co-
efficients greater than 0.5 m" .
The relationship between mean Secchi disc depth and mean
chlorophyll-a_ (equation 11-4) was used to compute a value for a for
each lake. Values for a ranged from essentially zero to 15 m with
an average of 1.35 m for all lakes.
Response Time
An important question related to any control option and its
effect on lake status is: how long, will it take to respond? The
response time is related to both the hydraulic residence time (V/Q)
and phosphorus retention coefficient. The response time for each
lake was computed according to the equation
0.69 (1 - R )
+ -
r
'1/2 Q/V
where:
t,/2 = time required to change from original
concentration halfway to the new steady-
state concentration
11-47
-------
CHLOROPHYLL a,;jg/l
FIGURE 11-28 THEORETICAL RELATIONSHIP BETWEEN SECCHI Disc
AND CHLOROPHYLL FOR VARIOUS VALUES OF <*
11-48
-------
a
a
NES DATA 1972-1975
i|93 LAKES
• DO
5-00 10-00 15-00 20-00 25-00 30.00 35-00 40-00
CHLOROPHYLL-A '(wG/L)
FIGURE 11-29 MEAN SECCHI Disc VERSUS MEAN CHLOROPHYLL-A
11-49
-------
NES DATA 1972
+
a
a
a_
a
s-~* a
CO •
— g
•
(_) &'
CO
i
4-
. . a
-p. a
<_J •*"
<_)
UJ
CO
;s °
-------
o
C3
CO '-\
rv 03
a
NES DATA 1974
OO
5
= §_
o -*
+ 4-
+ j.
a
a
a
I 7 + *
ri* "P J^ J, T X.
*P *Pr T J. T" "fr J. J* d«
* ^ + V ++ ^ + + f 1- +
5-00 LO-00 25-00 20-00 25-00 30-00 35-00 40-00
CHLOROPHYLL-A (nG/L)
a
a
^—N a
c^° +
LU
oo
(=5
-------
Rm = measured phosphorus retention coefficient
Q = volumetric flow rate (outlet)
V = lake volume
Figure 11-32 shows the cumulative distribution of response times
for all lakes in the screened data base. Only 16 lakes have times
greater than two years and over 80% of the lakes have a computed
"response time" of six months or less. These data indicate that 80%
of the lakes should be within 10% of a new steady-state condition with-
in two years of a step change in phosphorus loading.
However, it should be noted that the available data base did
not allow consideration of sediment phosphorus release. It is
possible that lakes which have received high loadings for a long
period of time may respond considerably more slowly while the sedi-
ments equilibrate with a new loading rate (Lorenzen, et al., 1976).
11-52
-------
NES DATA 1972-1975
CO . __
y 400
£ 300
CQ
16
200-
100
°0-00
0-40 0-80 1-20 1-GO
RESPONSE TIME (YEARS)
2-00
FIGURE 11-32 CUMULATIVE DISTRIBUTION OF LAKE RESPONSE TIMES
11-53
-------
SECTION III
TECHNICAL APPROACH
The approach used to analyze the consequences of various phos-
phorus control options was very straightforward and necessarily sim-
plified as dictated by available data. The procedure consisted
of four major steps.
1. Compute new phosphorus loading to each lake
2. Compute new in situ phosphorus concentration
3. Compute new chlorophyll-a_ and Secchi disc
4. Display results
The procedures used in each step are described below.
PHOSPHORUS LOADING
The method of computing phosphorus loading depends on the
specific option to be tested and is described for each option in
subsequent chapters. In general, loading rates from each type of
source (municipal, streams, septic tanks, etc.) are reduced by some
fraction which corresponds to the control option specified. A new
total phosphorus loading is then computed by subtracting any reduc-
tion from the original mass loading rate.
NEW PHOSPHORUS CONCENTRATION
A number of methods and models were reviewed for computation
of the lakes' response to changed loading. This review is documented
III-l
-------
in Appendix C, "Evaluation of Available Phosphorus Models". The
method chosen was the simple mass balance model which considers load-
ing, loss to the sediments, and discharge.
• -C-KLC (III-l)
where:
C = Annual average total phosphorus concentration, mg/1
t = time, years
3
Q = hydraulic flow, m /yr (outflow was assumed
equal to the inflow)
C.jn '-- average annual influent phosphorus concentration, mg/1
•3
V = lake volume, m
KL = sedimentation loss rate constant, yr"
The steady-state solution to this mass balance is
-1
C _ = C. ]
'ss in 1+ KL V/Q Vlli c/
There have been some theoretical attempts to relate K. to other
lake parameters (volume, area, mean depth). Here the value K. will
be shown to be related to the phosphorus retention coefficient, R ,
a parameter measured in the study and defined by the following equation:
R - mass in - mass out
m ~ mass in
(IH-3)
in nn " out %ut
Cin "in
III-2
-------
During steady state conditions C . in the above expression equals
C , the concentration at steady state. Likewise at steady state the
volumetric inflow and outflow rates are equal, hence Q. = Q . = Q.
Rewriting Equation III-3 for steady state conditions,
r D-P n r -r
in 4 ss ^ in <
R_ = n ss _ in .
Cin Q Cin
Substituting the expression for C from equation III-2 into Equation
j J
III-4 yields upon rearrangement:
Finally, the above equation can be solved for K, . This yields an
explicit equation for K, as a function of the phosphorus retention
coefficient Rm, and the reciprocal detention time Q/V:
Rm Q/V
The expression used in this study to compute new steady-state
mean annual phosphorus concentrations is the mass balance equation
(Equation III-4), solved for GSS.
Css - Cin (1 - Rm) (III-7)
The use of this equation assumes that the measured value of R
is correct, is representative of steady-state conditions, and will not
change when loading rates are changed. The data base screening pro-
cedures attempted to eliminate lakes which were not at steady-state by
rejecting lakes with negative retention coefficients or very long
residence times. There is no way to validate the other assumptions.
III-3
-------
A brief analysis of theoretical phosphorus retention coefficients
was conducted to determine if current theories could correctly predict
the measured values. The best relationship previously published was
that proposed by Larsen and Mercier (1975) in which the predicted
retention coefficient, R , was given by
P 1 + (Q/V
r = 0.94
Figure III-l shows a comparison of measured and predicted retention
coefficients using this relationship. It was decided that, in spite of
limitations, the observed phosphorus retention is the best available in-
dication of probably future retention in each lake and was used in subse-
quest analyses.
Because of the steady-state assumption, the phosphorus retention
coefficient was computed based on influent and effluent concentrations
assuming that the outflow was equal to the inflow for each lake. The
resulting equation for new phosphorus concentrations is simply:
C = C
new old
(New P Load \
Old P Load /
where C = predicted phosphorus concentration
C ,. = NES in situ median total phosphorus
concentration
New P Load = computed load with option
Old P Load = NES reported total phosphorus load
It should also be noted that the analysis was based on the median
observed phosphorus concentrations. Since mean values were not volume-
weighted, the medians were judged to be a better measure of central
tendency and therefore were used and treated as mean values for predic-
tive purposes.
III-4
-------
1
Rm =
(Q/VP + 1
mass in - mass out
mass in
Q = hydraulic outflow
V = lake volume
u
LU
H-»
o
o
o
UJ
cc
o
o
1.0.
0.8
0.6
0.4.
0.2
0.2
0.4
0.6
0.8
1.0
MEASURED RETENTION COEFFICIENT (Rj
FIGURE III-l
RELATIONSHIP BETWEEN THEORETICAL
AND MEASURED PHOSPHORUS RETENTION
COEFFICIENTS
III-5
-------
NEW CHLOROPHYLL CONCENTRATIONS
The prediction of new chlorophyll concentrations following a
reduction in phosphorus loading is a very sensitive issue. Assuming
that new phosphorus concentrations can be predicted, many researchers
(Dillon and Rigler, 1974; Jones and Bachman, 1976), have proposed the
use of regression equations which relate chlorophyll to total phos-
phorus. The problem with this type of relationship is that there is
a very wide scatter (masked by log-log plots) that may be a result
of the fact that in many lakes chlorophyll production may not be
limited by available phosphorus. The mixed depth, light attenuation
characteristics, residence time, or other factors may control the
maximum algal yield.
The data which were presented in Figures 11-10 through 11-27
clearly illustrate that the use of a simple regression equation for
chlorophyll-^ as a function of total phosphorus would not be appropri-
ate. If a line of best fit were used and new chlorophyll concentrations
computed as a result of reduction in phosphorus concentration, approxi-
mately one-half of the lakes would show less chlorophyll with no change
in loading (those lakes which fall above the regression line). Like-
wise, those lakes which fall below the regression line would show more
chlorophyll with no change in phosphorus loading.
Because of these difficulties and consideration of theoretical
yield concepts it was decided to compute a new chlorophyll concentra-
tion based on the assumption that chlorophyll yield would not be reduced
unless total phosphorus were reduced to a low enough level to impose
phosphorus limitation in accordance with the line bounding the data.
The new chlorophyll-a_ concentration was therefore computed to be
equal to the old value or 1.0 times the new phosphorus concentration
in yg/1, whichever is less. This procedure is illustrated in Figure
III-6
-------
III-2 which shows chlorophyll-a_ versus total phosphorus for all lakes
included in the data base. For the example shown, no decrease in
chlorophyll-a would be predicted until median total phosphorus is
reduced below 0.03 mg/1.
NEW SECCHI DISC
The new Secchi disc depth for each lake was computed according
to the theoretical relationship:
Secchi disc depth = a '+ ^
.C = chlorophyll concentration
The value of 3 was assumed to be 0.03 nfVyg/l chlorophyll-a
(Lorenzen, 1972). The value of a was computed for each lake using
Equation II-4 as described earlier.
The new Secchi disc depth was then computed for each new
chlorophyll concentration.
PRESENTATION OF RESULTS
When such large quantities of data and computations are used,
it is difficult to present results which are understandable and at
the same time comprehensive. Tabulated results for new and old
values of phosphorus loading, in situ phosphorus concentration, chloro-
phyll-£ and Secchi disc for each lake are given in Appendix B for each
option.
These data are displayed graphically in cumulative frequency plots
for each parameter and by geographical area when differences were
found. For each plot, the "base case" or condition measured during the
NES is shown for comparison.
III-7
-------
Chi a (jig/8) = 1000P(mg/?)
i
00
100 -i
00
Example: Effect of
Reduced phosphorus on
mean Chlorophyll a
p T 4- T"
+^tt--t-+ "*" * + +4- + >
•K + * +•
0.00 0.05 0.10 0.15 0.20 0.25
MEDIAN TOTAL P,
0.30 0.35
0.40
FIGURE III-2 MEAN CHLOROPHYLL-A_ VERSUS MEDIAN TOTAL PHOSPHORUS (493 LAKES)
(HEAVY LINE SHOWS EFFECT OF REDUCING PHOSPHORUS ON CHLOROPHYLL-A)
-------
SECTION IV
CONTROL OPTION I
DETERGENT PHOSPHORUS CONTROL
The purpose of this study is to analyze the effect of various
phosphorus control options on lake water quality on a national scale.
The analysis is based on 493 lakes distributed throughout the country
for which data are available as a result of the National Eutrophica-
tion Survey. This section describes the results of analyzing the
effects of controlling phosphorus in detergents.
"During the period of the lake survey, the contribution
to sewage phosphorus from detergents decreased in response to
a nationwide reduction in the phosphorus content of detergent
formulations. EPA believed that in the early 1970s (the be-
ginning of the lake survey), about 50-60% of the phosphorus
in sewage was thought to be derived from detergents, as evi-
denced by data from municipalities where phosphate detergents
were banned (Region V Phosphorus Committee, 1977). At the
end of the survey, this figure was thought to be closer to
30-35% (Booman, 1978,). EPA chose the midpoint of this range
(45%) to reflect the average contribution to sewage phosphorus
from detergents throughout the nation during the survey.
Areas that differed from this figure (e.g. New York and Indiana)
received special treatment when they were identified.
"Two levels of control were evaluated: (1) complete phos-
phate detergent ban, corresponding to a 45% reduction in munic-
ipal treatment plant effluent concentration, and (2) limitation
of detergent phosphorus to 3% which would imply a 27% reduction
in municipal loading. The latter analysis was included to re-
flect interest of detergent formulators in a 3% P:18% zeolite
formulation. The 3% P formulation was considered a 60% reduction
in current detergent phosphorus levels and correspond to a 27%
reduction (average) in phosphorus concentration in NES effluents."
(Welch, 1979)
METHODS
The procedures followed were as described in Section III. For all
states except Indiana and New York, which had detergent phosphorus bans
during part of all of the Survey (phosphorus loads to lakes in Indiana
IV-1
-------
and New York were not changed), the total phosphorus load from municipal
sources was reduced by 45 and 27 percent. A new total load to each lake
was then computed assuming loads from other sources (runoff, streams,
industrial, precipitation) remained the same.
After computing a new total load for each lake, the predicted in situ
steady state concentration of phosphorus was computed according to the
procedure described in Section III. Chlorophyll-a and Secchi disc depths
were subsequently computed for each lake as described previously. All
computed values represent annual averages for each lake at steady-state.
The response time of each lake was computed as described in Chapter
III. Since only 3% (16 lakes) of the lakes had a response time of greater
than two years, it was felt that most lakes would not be too far from
equilibrium and only the steady-state results are shown.
RESULTS (all lakes)
Values of old and new total phosphorus loading, average in situ phos-
phorus concentration, chlorophyll-a_ concentration and Secchi disc depth
for each lake and each control level (45% and 27%) are tabulated in Appen-
dix B-l, both by geographical area (year surveyed) and for all lakes com-
bined.
Figures IV-1 through IV-4 show the distribution of parameter values
for the base case (NES data) and each control level for all lakes. Plots
for subsets of lakes by geographical area (year surveyed) are contained
in Appendix B-l.
It is readily apparent that the results indicate that even a complete
ban of detergent phosphorus would have a very little effect on the trophic
condition of the NES lakes as a whole. For all 493 lakes the median total
phosphorus would decrease from 0.084 mg/1 to 0.070 mg/1. Computed changes
in chlorophyll-a_ and Secchi disc are negligible. Of the 493 lakes, the
number with a median total phosphorus concentration less than the recom-
mended 0.025 mg/1 would increase from 160 to 164.
IV-2
-------
500-,
CO
400-
300-
200-
100-
— base case
x 27% reduction
O 45% reduction
10'
105 104 10y 10b
TOTAL PHOSPHORUS LOADING RATE (KG/YR)
10'
FIGURE IV-1
DISTRIBUTION OF NEW AND OLD PHOSPHORUS
LOADING RATES, OPTION 1
IV-3
-------
INDICATES NUMBER
OF LAKES >1.0
0.2 0.1 0.6 0.8 1,0
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION
00
CD
m 300 ^
ca
SI
an
0.02 0.04 0.06 0.08 0.10 >0.10
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION
FIGURE IV-2 DISTRIBUTION OF NEW AND OLD MEDIAN
PHOSPHORUS CONCENTRATIONS, OPTION 1
IV-4
-------
O
Oi
UJ
CQ
g
9 x
9 «•
100-
20
40 60 80
MEAN CHLOROPHYLL-A (yG/L)
>100
CD
a;
200 j
100,
8.0 12.0 16.0 20.0
MEAN CHLOROPHYLL-A (yG/L)
100
100X
>20.0
FIGURE IV-3
DISTRIBUTION OF NEW AND OLD CHL.OROPHYLL-A
CONCENTRATIONS^ OPTION 1
IV-5
-------
500-
8 400-i
Sj 300 H
PQ
200-
100-
0
1,0
2,0 3,0 4,0 5,0
MEAN SECCHI DISC (M)
10
10 X
10 o
6,0
FIGURE IV-4
DISTRIBUTION OF NEW AND OLD SECCHI Disc
DEPTHS., OPTION 1
IV-6
-------
Table IV-1 summarizes the phosphorus concentration data with the
original loading and the new reduced phosphorus loading. Table IV-2
summarizes the number and percent of the total lakes that would have
a total phosphorus concentration less than 0.025 mg/1, both with and
without a 45% reduction in municipal treatment plant phosphorus dis-
charges.
Table IV-1
Effect of Control Option 1 on In Situ
Total Phosphorus Concentrations
Year
Surveyed
1972
1973
1974
1975
1972-75
Original Loading
Concentration, mg/1
Minimum
0.004
0.006
0.010
0.006
0.004
Mean
0.141
0.070
0.075
0.045
0.084
Maximum
1.525
0.865
0.489
0.371
1.525
New Loading
(45% Reduction in Municipal)
Concentration, mg/1
Minimum
0.004
0.004
0.008
0.006
0.004
Mean
0.101
0.060
0.073
0.043
0.070
Maximum
0.944
0.660
0.458
0.371
0.944
IV-7
-------
Table IV-2
Number and Fraction of Lakes with Median
Phosphorus Concentrations Less Than 0.025 mg/1
Year
Surveyed
1972
1973
1974
1975
1972-75
Number
of
Lakes
Surveyed
119
165
115
94
493
Lakes with Total P
<0.025 mg/1
Old
#
36
53
27
44
160
%
30.3
32.1
23.5
46.8
32.5
New
#
-38
54
27
45
164
%
31.9
32.7
23.5
47.9
33.3
Difference
(New - Old)
# %
2 1.6
1 0.6
0 0.0
1 1.1
4 0.8
IV-8
-------
RESULTS (lakes with municipal treatment plants)
Because the results of these options were barely distinguishable
from the present condition, a separate analysis of only lakes with
treatment plants was conducted. The results were not noticeably dif-
ferent from the results shown. Essentially, the only difference was
that the four additional lakes with median phosphorus concentrations
less than 0.025 mg/1 would represent 1.2% of the number of lakes with
treatment plants rather than 0.8% of the total number of lakes.
IV-9
-------
SECTION V
CONTROL OPTION 2
TERTIARY SEHAGE TREATMENT
(80% P REMOVAL)
This section describes the results of analyzing the effects of 80
percent phosphorus removal from municipal sewage treatment plants.
Figure V-l illustrates the distribution of old and new treatment plant
effluent phosphorus concentrations for all lakes. The 80% reduction
resulted in a narrower range of values, the mean being 1.0 mg/1.
Figures V-2 and V-3 show the new and old effluent concentrations
for treatment plant effluent in the different geographical regions
represented by each year's survey.
METHODS
The procedures followed were as described in Section III. The total
phosphorus load from municipal sources was reduced by 80 percent. A new
total load to each lake was then computed assuming loads from other
sources (runoff, streams, industrial, precipitation) remained the same.
After computing a new total load for each lake, the predicted in situ
steady-state concentration of phosphorus was computed according to the
procedure described in Section III. Chlorophyll-a_ concentrations and
Secchi disc depths were subsequently computed for each lake as described
previously. All computed values represent annual averages for each lake
at steady-state.
V-l
-------
oo
500
400"
300-
200-
100-
0.00
ALL LAKES
base case
4.00 8.00 12.00 16.00
STP EFFLUENT P CONCENTRATION (mg/1)
20.00
FIGURE V-l DISTRIBUTION OF SEWAGE TREATMENT
PLANT EFFLUENT PHOSPHORUS CONCENTRATIONS,
OPTION 2
V-2
-------
00
UJ
u.
o
UJ
CO
<
o
120H
1972 Data
base case
80% reduction
4.00 8.00 12.00 16.00
STP EFFLUENT P CONCENTRATION (mg/1)
20.00
oo
LU
cc.
UJ
CD
•f.
O
1973 Data
o ^--
0.00
FIGURE V-2
30-
4.00 8.00 12.00 16.00
STP EFFLUENT P CONCENTRATION (mg/1)
20.00
DISTRIBUTION OF SEWAGE TREATMENT PLANT
EFFLUENT PHOSPHORUS CONCENTRATIONS, OPTION 2
V-3
-------
CO
LU
u_
o
CD
120-1
90-
60,
30-
1974 Data
0.00 4.00 8.00 12.00 16.00
STP EFFLUENT p CONCENTRATION (mg/1)
20.00
CO
CO
<:
o
120
90
1975 Data
4.00 8.00 12.00 16.00
STP EFFLUENT P CONCENTRATION (mg/1)
20.00
FIGURE V-3
DISTRIBUTION OF SEWAGE TREATMENT PLANT
EFFLUENT PHOSPHORUS CONCENTRATIONS, OPTION 2
V-4
-------
RESULTS (all lakes)
Values of old and new total phosphorus loading, average in situ
phosphorus concentration, chlorophyll-a concentration and Secchi disc
depth for each lake are tabulated in Appendix B-2, both by geographical
area (year surveyed) and for all lakes combined.
Figures V-4 through V-7 show the distribution of parameter values
for the base case (NES data) and the control option for all lakes.
Plots for subsets of lakes by geographical region are contained in
Appendix B-2.
It is apparent from the results presented that tertiary treatment
(80% reduction in effluent phosphorus concentration) of municipal sewage
should have a small but detectable effect on lake phosphorus concen-
trations. For example, as shown in Table V-l, the median total phos-
phorus concentration for all 493 lakes should decrease from 0.084 mg/1 a
to 0.059 mg/1. Table V-2 shows that the percent of lakes which have
total phosphorus concentrations less than 0.025 mg/1 should increase
.from 32.5% to 37.9% (27 lakes). The effects would be most pronounced
in the Northeast and North-Central lakes where larger fractions of total
phosphorus loads are from sewage treatment plants.
In spite of predicted decreases in phosphorus concentrations, the
analysis indicates little or no improvement in terms of chlorophyll-a_
or Secchi disc depth. This lack of biological response is because most
lakes in the sample would require a substantial reduction in total
phosphorus loading before phosphorus could be made to limit chlorophyll-a_
to low levels.
RESULTS (lakes with municipal treatment plants)
Because not all of the lakes included in the data base received
municipal sewage treatment plant effluent, a separate analysis was conducted
V-5
-------
to
LU
cc
LU
CO
500 -i
400-
300-
200-
100-
100
1,000 10,000 100,000 106
Total Phosphorus Loading (kg/yr)
base case
80% reduction
10'
FIGURE V-4 DISTRIBUTION OF NEW AND OLD PHOSPHORUS
LOADING RATES, OPTION 2
V-6
-------
0.4 0.6 0.8
MEDIAN PHOSPHORUS (mg/1)
INDICATES NUMBER
OF LAKES >1.0
1.0
3 x
0.02
FIGURE V-5
0.04 0.06 0.08
MEDIAN PHOSPHORUS (mg/1)
DISTRIBUTION OF NEW AND OLD MEDIAN
PHOSPHORUS CONCENTRATIONS, OPTION 2
V-7
-------
20
9
9 x
40 60 80
MEAN CHLOROPHYLL-A (yg/1)
T 1 I 1
100 >100
500 n
20.0
100
98 x
>20.0
8.0 12.0 16.0
MEAN CHLOROPHYLL-A (yg/1)
FIGURE V-6 DISTRIBUTION OF NEW AND OLD
CHLOROPHYLL-A CONCENTRATIONS, OPTION 2
V-8
-------
1.0
2.0 3.0 4.0 5.0
MEAN SECCHI DISC (M)
10
10 x
>6.0
FIGURE V-7 DISTRIBUTION OF NEW AND OLD SECCHI
Disc DEPTHS, OPTION 2
V-9
-------
Table V-l
Effect of Control Option 2 on In Situ
Total Phosphorus Concentrations
Year
Surveyed
1972
1973
1974
1975
1972-75
Original Loading
Concentration, mg/1
Minimum
0.004
0.006
0.010
0.006
0.004
Mean
0.141
0.070
0.075
0.045
0.084
Maximum
1.525
0.865
0.489
0.371
1.525
New Loading
(80% Reduction in Municipal)
Concentration, mg/1
Minimum
0.004
0.005
0.007
0.006
0.004
Mean
0.070
0.053
0.071
0.042
0.059
Maximum
0.795
0.500
0.438
0.371
0.795
Table V-2
Number and Fraction of Lakes with Median Phosphorus
Concentrations Less Than 0.025 mg/1
Year
Surveyed
1972
1973
1974
1975
1972-75
Number
of
Lakes
119
165
115
94
493
Lakes with Total P
<0.025 mg/1
Old
#
36
53
27
44
160
%
30.3
32.1
23.5
46.8
32.5
New
#
50
59
31
47
187
%
42.0
35.8
27.0
50.0
37.9
Change
(New - Old)
#
14
6
4
3
27
%
11.7
3.7
3.5
3.2
5.4
V-10
-------
for the set of lakes which do receive municipal effluent. It should be
noted that in the NES survey a treatment plant located within 40 km (25
miles) of a lake was considered a municipal source. Plants located at
more distant points on tributaries were not identified.
Table V-3 lists the total number of lakes in each years survey and
the number of lakes which receive municipal effluent.
Figure V-8 shows the cumulative distribution of median phosphorus
concentrations for the set of lakes (347 lakes) that have municipal
sources. These data can be compared with Figure V-5, which is for all
lakes surveyed. By considering only lakes with municipal sources the
regional bias is removed and results are shown for the country as a
whole. For this set of lakes the average total phosphorus concentration
was predicted to decrease from 0.099 mg/1 to 0.062 mg/1. The number of
lakes with a total phosphorus concentration less than 0.025 mg/1 would
increase from 90 to 117 (27 lakes) or 8.6 percent.
Predicted new chlorophyll-a_ and Secchi disc values were indistin-
guishable from the old values.
V-ll
-------
Table V-3
Number of Lakes Surveyed and Number With
Municipal Sources
Year
Surveyed
1972
1973
1974
1975
1972-75
Number of Lakes
Surveyed
119
165
115
94
493
Number of Lakes
With Municipal
Sources
100
135
69
43
347
Percent
With
Municipal
Sources
84
82
60
46
70
Note: Loads from lakes in New York and Indiana were not changed.
The resulting number of lakes with a computed decrease
in load from municipal treatment was 335.
V-12
-------
I/O
O
o;
LU
CQ
350 n
280 -
210 .
140-
70-
0.2
I/O
or
UJ
GQ
O
350-
280-
210-
140 -
70-
FlGURE V-8
0.02
0.4 0.6 0.8
MEDIAN PHOSPHORUS (mg/1)
1.0
0.08
81
57 x
0.10
>0.10
0.04 0.06
DISTRIBUTION OF NEW AND OLD MEDIAN PHOSPHORUS
CONCENTRATIONS (LAKES WITH MUNICIPAL TREATMENT
PLANTS), OPTION 2
V-13
-------
SECTION VI
CONTROL OPTION 3
20% NONPOINT SOURCE CONTROL
This section describes the results of analyzing the effects of a
20% reduction in nonpoint source phosphorus loading. The mass loadings
of phosphorus from "rivers" and "direct runoff" were reduced by 20%.
Figure VI-1 illustrates the distribution of old and new total phosphorus
loading rates. It is evident that a 20% reduction in nonpoint source
loads does not have a marked effect on loading.
METHODS
The procedures followed were as described in Section III. After
computing a new total phosphorus load to each lake, the predicted iji situ
steady-state concentration of phosphorus was computed according to the
procedures described in Section III. Chlorophyll-a_ concentrations and
Secchi isc depths were subsequently computed for each lake. All computed
values represent annual averages for each lake at steady-state.
RESULTS
Values of old and new total phosphorus loading, average in situ
phosphorus concentration, chlorophyll-a_ concentration and Secchi disc
depth for each lake are tabulated in Appendix B-3, both by geographical
area (Figure 11-13, page 11-30) and for all lakes combined.
Figures VI-2 through VI-4 show the distribution of parameter values
for the base case (NES data) and the control option for all lakes. New
VI-1
-------
500
co
O
CQ
1001
300
case
.'0% nonpoint
source reduction
5
10
PHOSPHORUS LOADING (KG/YR)
10
6
10
7
FIGURE VI-1 DISTRIBUTION OF NEW AND OLD
PHOSPHORUS LOADING RATES,
OPTION 3
VI-2
-------
500 i
100-
LU
-------
500 n
400-
g 300
CQ
200-
100
g
9 x
60 80
MEAN CHLOROPHYLL-A (yG/L)
>100
C/5
UJ
20.0
FIGURE VI-3
DISTRIBUTION OF NEW AND OLD MEAN
CHLOROPHYLL-A CONCENTRATIONS,, OPTION 3
VI-4
-------
500 -,
GO 400
LU
U_
o
300 -
CQ
6.0
FIGURE VI-4 DISTRIBUTION OF NEW AND OLD MEAN SECCHI Disc
DEPTHS, OPTION 3
VI-5
-------
and old median phosphorus concentrations for the lakes within each of
the seven geographical areas are shown in Figures VI-5 through VI-11.
Because the chlorophyll-a_ levels and Secchi disc depths were
relatively insensitive to changed phosphorus loading the following dis-
cussion is limited to effects of the control option on phosphorus concen-
trations.
For all 493 lakes used in the data base the effect of a 20% nonpoint
source phosphorus red1 ••-•*--" ~n -^ -^~wn --'P c-;gure VI-? The mean value of
predicted phosphorus concentrations is 0.074 mg/£ compared to 0.084 with
no control. The number of lakes with a median phosphorus concentration
less than 0.025 mg/£ increased from 160 to 183.
Table VI-1 summarizes the results for all lakes and for subsets of
lakes grouped by geographical area. Table VI-2 summarizes the number and
fraction of lakes with median phosphorus concentrations less than 0.025 mg/a.
VI-6
-------
CO
UJ
1201
100-
80-
o
DC
S 60-1
<£
? 40-1
20-
36
34 X
BASE CASE
OPTION 3
0.02 0.04 0.06 0.08 0.1
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (MG/L)
FIGURE VI-5 DISTRIBUTION OF NEW AND OLD MEDIAN PHOSPHORUS
CONCENTRATIONS FOR LAKES IN AREA 1, OPTION 3
VI-7
-------
izu-
100-
80-
UJ
CQ
60-
20-
24
17 x
0.02 0.04 0.06 0.08 0.1
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (MG/L)
FIGURE VI-6 DISTRIBUTION OF NEW AND OLD MEDIAN PHOSPHORUS
CONCENTRATIONS FOR LAKES IN AREA 2, OPTION 3
VI-8
-------
120 -i
100 -
80-
60-
CD
40-
20-
3
I x
0,0,2 0.04 0.06 0.08 OJ
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (MG/L)
FIGURE VI-7 DISTRIBUTION OF NEW AND OLD MEDIAN PHOSPHORUS
CONCENTRATIONS FOR LAKES IN AREA 3, OPTION 3
VI-9
-------
120-i
100-
GO
LU
i*:
3
80-
60-
40-
20-
11
10 x
0.02 0.04 0.06 0.08 0.1
MED I AiMN-LAKE."PHOSPHORUS CONCENTRATION (MG/L)
FIGURE VI-8 DISTRIBUTION OF NEW,AND OLD MEDIAN PHOSPHORUS
CONCENTRATIONS FOR LAKES IN AREA 4, OPTION !>
VI-10
-------
120 i
100-
80-
o
oc
LLJ
PQ
60-
20-
12
8 x
-II-
0,02 0.04 0,06 0.08 0.1
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (MG/L)
FIGURE VI-9 DISTRIBUTION OF NEW AND OLD MEDIAN PHOSPHORUS
CONCENTRATIONS FOR LAKES IN AREA 5, OPTION 3
vi-n
-------
120-1
100-
CO
a
5
CQ
-------
120-1
100-
CO
LU
^
3
o:
UJ
CO
80-
60-
20-
6
6 x
0,02 0,04 0.06 0,0.8 1.0
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (MG/L)
-ii 1
FIGURE VI-ll
DISTRIBUTION OF NEW AND OLD MEDIAN PHOSPHORUS
CONCENTRATION'S'FOR LAKES IN AREA 7, OPTION 3
VI-13
-------
Table VI-1
Effect of Control Option 3 on J_n Situ
Total Phosphorus Concentrations
Region
1
2
3
4
5
6
7
All
Number
of
Lakes
120
108
56
32
83
41
53
493
Original Loading
Concentration, mg/£
Minimum
0.004
0.006
0.007
0.011
0.010
0.006
0.007
0.004
Mean
0.141
0.086
0.041
0.121
0.058
0.034
0.054
0.084
Maximum
1.525
0.865
0.143
0.489
0.424
0.115
0.371
1.525
New Loading *
( 20% Nonpoint Reduction )
Concentration, mg/Jl
Minimum
0.003
0.005
0.006
0.009
0.008
0.005
0.006
0.003
Mean
0.132
0.073
0.035
0.099
0.048
0.028
0.045
0.074
Maximum
1.522
0.784
0.136
0.405
0.339
0.100
0.298
1.522
Table VI-2
Number and Fraction of Lakes with Median Phosphorus
Concentrations Less Than 0.025 mg/Jl
Region
1
2
3
4
5
6
7
All
Number
of
Lakes
120 .
108
56
32
83
41
53
493
Lakes with Total P
<0.025 mg/£
Old
#
37
29
23
3
24
20
24
160
%
31
27
41
9
29
49;
45
32
New
#
41
33
25
4
29
24
27
183
%
34 .
31
45
13
35
59
51
37
Change
(New - Old)
#
4
4
2
' '1
5
4
3 .
23
%
3
4
4
4
6
10
6
5
VI-14
-------
SECTION VII
CONTROL OPTION 4
40% NONPOINT SOURCE CONTROL
This section describes the results of analyzing the effects of a
40% reduction in nonpoint source phosphorus loading. The mass loadings
of phosphorus from "rivers" and "direct runoff" were reduced by 40%.
Figure VII-1 illustrates the distribution of old and new total phos-
phorus loading rates. It is evident that a 40% reduction in nonpoint
source loads has a marginal effect on loading rates.
METHODS
The procedures followed were as described in Section III. After
computing a new total phosphorus load to each lake, the predicted
jm situ steady-state concentration of phosphorus was computed accord-
ing to the procedures described in Section III. Chlorophyll-a
concentrations and'Secchi disc depths were subsequently computed for
each lake. All computed values represent annual averages for each lake
at steady-state.
RESULTS
Values of old and new total phosphorus loading, average in situ
phosphorus concentration, chlorophyll-a^ concentration and Secchi disc
depth for each lake are tabulated in Appendix B-4, both by geographi-
cal area (Figure 11-13, page 11-30) and for all lakes combined.
Figures VII-2 through VII-4 show the distribution of parameter
values for the base case (NES data) and the'Control option for all
VII-1
-------
5001
NES DATA 1972-1975
CO
UJ
400-
300-
CQ
200-
100-
— base case
x 40% nonpoint
source reduction
10-
10L
10
5
PHOSPHORUS LOADING (KG/YR)
FIGURE VII-1 DISTRIBUTION OF NEW AND OLD
PHOSPHORUS LOADING RATES.,
OPTION 4
10
7
VII-2
-------
3
3 X
0.2 0.4 0.6 0.8 1,0
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (MG/L)
500 -i
100-
300-
pa
P 200
100-
0.02 0.04 0.06 0.08 0.10
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (MG/L)
9-7
71
FIGURE VI1-2 DISTRIBUTION OF NEW AND OLD MEDIAN PHOSPHORUS
CONCENTRATIONS, OPTION 4
VII-3
-------
c/,
UJ
i«i
3
u_
500
100-1
300 H
200 -
100 -
20
40 60 80
MEAN CHLOROPHYLL-A (yG/L)
100
g
s x
-II —H
>100
5001
CO
UJ
_
S 300
03
200-
100-
4.0
8.0 12.0 16.0
MEAN CHLOROPHYLL-A (yG/L)
100
100X
20.0
HI • 1
>20.0
FIGURE VII-3
DISTRIBUTION OF NEW AND OLD MEAN
CHLOROPHYLL-A CONCENTRATIONS., OPTION
VII-4
-------
500-1
400 H
LU
3
u_
o
300-
03
P 200-
100-
1.0 2.0 3.0 4.0 5.0
MEAN SECCHI DISC (M)
10
10 x
-11——i
6.0 >6.0
FIGURE VII-4 DISTRIBUTION OF NEW AND OLD MEAN SECCHI Disc
DEPTHS, OPTION 4
VII-5
-------
lakes. New and old median phosphorus concentrations for the lakes within
each of the seven geographical areas are shown in Figures VI1-5 through
VII-11.
Because the chlorophyll-a^ levels and Secchi ^isc depths were rela-
tively insensitive to changed phosphorus loading the following discussion
is limited to effects of the control option on phosphorus concentrations.
For all 493 lakes used in the data base the effect of a 40% nonpoint
source phosphorus reduction is shown in Figure VII-2. The mean value of
predicted phosphorus concentration is 0.064 mg/£ compared to 0.084 with
no control. The number of lakes with median phosphorus concentrations
less than 0.025 mg/fc increased from 160 to 218.
Table VII-1 summarizes the results for all lakes and for subsets of
lakes grouped by geographical area. Table VII-2 summarizes the number
and fraction of lakes with median phosphorus concentrations less than
0.025 mg/£.
VII-6
-------
co
UJ
UJ
CO
120 -i
100-
80-
60-
40-
20-
36
33 X
base case
0.02 0,04 0.06 0.08 0.1
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (M.G/L)
FIGURE VI1-5 DISTRIBUTION OF NEW AND OLD MEDIAN PHOSPHORUS
CONCENTRATIONS FOR LAKES IN AREA 1, OPTION l\
VII-7
-------
100-
80-
60-
20-
24
U x
0.02 0.04 0.06 0.08 0.1
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (MG/L)
FIGURE VI1-6 DISTRIBUTION OF NEW AND OLD MEDIAN PHOSPHORUS
CONCENTRATIONS FOR LAKES IN AREA 2, OPTION 4
VII-8
-------
120 -1
100 |
80-
OQ
60-
40-
20-
3
I x
0.02 0.04 0.06 0.08 0.1
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (MG/L)
-II 1
FIGURE VI1-7 DISTRIBUTION OF NEW AND OLD MEDIAN PHOSPHORUS
CONCENTRATIONS FOR LAKES IN AREA 3, OPTION 4
VII-9
-------
120-1
100-
oo
LU
_
o
o;
80-
60-
40-
20-
11
10 x
0.02 0,01 0,06 0.08 O'.l
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (MG/L)
FIGURE VII-8 DISTRIBUTION OF NEW AND OLD MEDIAN PHOSPHORUS
CONCENTRATIONS FOR LAKES IN AREA 4, OPTION 4
VII-10
-------
1201
100-
GO
03
80-
60-
20-
0.02 0.04 0.06 0.08 0.1
. MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (MG/L)
|
12
4 x
•-0.1
FIGURE VI'I-9
DISTRIBUTION OF NEW AND OLD MEDIAN PHOSPHORUS
CONCENTRATIONS FOR. LAKES, .IN AREA 5, OPTION 4
VII-ll
-------
. 12(h
100-
GO
LU
^i
3
-------
120-.
100-
00
UJ
' 5
o;
UJ
03
80-
60-
40-
6
6 x
0.02 0.04 0.06 0.08 1.0
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (MG/L)
FIGURE-VII-ll DISTRIBUTION OF NEW AND OLD MEDIAN PHOSPHORUS
CONCENTRATIONS FOR LAKES IN AREA 7, OPTION 4
VII-13
-------
Table VII-1
Effect of Control Option 4 on In Situ
Total Phosphorus Concentrations
Region
1
2
3
4
5
6
7
All
Number
of
Lakes
120
108
56
32
83
41
53
493
Original Loading
Concentration, mg/£
Minimum
0.004
0.006
0.007
0.011
0.010
0.006
0.007
0.004
Mean
0.141
0.086
0.041
0.121
0.058
0.034
0.054
0.084
Maximum
1.525
0.865
0.143
0.489
0.424
0.115
0.371
1.525
New Loading
(40% Nonpoint Source Reduction)
Concentration, mg/£
Minimum
6.003
'0.004
0.004
0.007
0.006
0.004
0.005
0.003
Mean
0.124
0.064
0.029
0.076
0.038
0.022
0.036
0.064
Maximum
1.520
0.703
0.128
0.321
0.254
0.084
0.225
1.520
Table VII-2
Number and Fraction of Lakes with Median Phosphorus
Concentrations Less Than 0.025 mg/i
Region
1
2
3
4
5
6
7
All
Number
of
Lakes
120 :
108
56
32
83
41
53
493
Lakes with Total P
<0.025 mg/A '
Old
#
37
29
23
3
24
20
24
160
%
31
27
41
9
29
49
45
32
New
#
48
40
29
5
38
28
30
218
%
40
37
52
16
46
68
57
44
Change
(New - Old)
#
11
11
6
2
14
8
6
58
%
9
10
11
7
17
19
12
12
VII-14
-------
SECTION VIII
CONTROL OPTION 5
60% NONPOINT SOURCE CONTROL
This section describes the results of analyzing the effects of a
60% reduction in nonpoint source phosphorus loading. The mass loadings
of phosphorus from "rivers" and direct runoff" were reduced by 60%.
Figure VIII-1 illustrates the distribution of old and new total phos-
phorus loading rates. It is evident that a 60% reduction in nonpoint
source loads has an effect on total loading rates.
METHODS
The procedures followed were as described in Section III. After
computing a new total phosphorus load to each lake, the predicted
_in_ situ steady-state concentration of phosphorus was computed according
to the procedures described in Section III. Chlorophyll-a_ concen-
trations and Secchi disc depths were subsequently computed for each
lake. All computed values represent annual averages for each lake at
steady-state.
RESULTS
Values of old and new total phosphorus loading, average in situ
phosphorus concentrations, chlorophyll-a concentration and Secchi disc
depth for each lake are tabulated in Appendix B-5, both by geographical
area (Figure 11-13, page 11-30) and for all lakes combined.
Figures VIII-2 through VIII-4 show the distribution of parameter
values for the base case (NES data) and the control option for all
VIII-1
-------
500-
CO
UJ
^s:
3
u_
o
cc:
UJ
oa
300H
200H
— base case
x 60% nonpoint
source reduction
5
103 104 10
PHOSPHORUS LOADING (KG/YR)
10
6
10
7
FIGURE VIII-1 DISTRIBUTION OF NEW AND OLD
PHOSPHORUS LOADING RATES,
OPTION 5
VIII-2
-------
3
3 X
0.2 0.4 0.6 0.8 1.0
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (MG/L)
-11-
500i
400-
S 300H
CO
P 200H
100-
37
53 x
0.02 0.04 0.06 0.08 0.10
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (MG/L)
FIGURE VI11-2
DISTRIBUTION OF NEW AND OLD MEDIAN PHOSPHORUS
CONCENTRATIONS, OPTION 5
VIII-3
-------
00
LU
ZxZ
3
5001
400-
£ 300 H
200-
100-
20
9
7 x
-II-
0 60 80
MEAN CHLOROPHYLL-A (yG/L)
100
>100
500-1
_
£ 300-
CO
_
P 200
100-
4.0
100
95 x
8.0 12.0 _ 16.0
MEAN CHLOROPHYLL-A (uG/L)
20,0
>20.0
FIGURE VIII-3
DISTRIBUTION OF NEW AND OLD MEAN
CHLOROPHYLL-A CONCENTRATIONS, OPTION 5
VI11-4
-------
500 -i
400 H
LU
i«i
3
IJ-
CS
300 H
CQ
S 200 H
100 H
1,0 2,0 3.0 1,0
MEAN SECCHI DISC (M)
5.0
10
10
6.0
>6.0
FIGURE VI11-4 DISTRIBUTION OF NEW AND OLD MEAN SECCHI Disc
DEPTHS, OPTION 5
VIII-5
-------
lakes. New and old median phosphorus concentrations for the lakes
within each of the seven geographical areas are shown in Figures
VIII-5 through VIII-11.
Because the chlorophyll-a levels and'Secchi disc depths were
relatively insensitive to changed phosphorus loading the following
discussion is limited to effects of the control option on phosphorus
concentrations.
For all 493 lakes used in the data base the effect of a 60%
nonpoint source phosphorus reduction is shown in Figure VIII-2. The
mean value of predicted phosphorus concentration is 0.055 mg/£ com-
pared to 0.084 with no control. The number of lakes with median
phosphorus concentrations less than 0.025 mg/£ increased from 160
to 273.
Table VIII-1 summarizes the results for all lakes and for sub-
sets of lakes grouped by geographical area. Table VIII-2 summarizes
the number and fraction of lakes with median phosphorus concentrations
less than 0.025 mg/JL
VIII-6
-------
00
LU
i^
U_
o
cc
UJ
CQ
120-1
100-
80-
60-
40-
20-
36
31 X
Option 5
base case
0,02 0.04 0.06 0.08 0.1
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (MG/L)
FIGURE VIII-5
DISTRIBUTION OF NEW AND OLD MEDIAN PHOSPHORUS
CONCENTRATIONS FOR LAKES IN AREA 1, OPTION 5
VIII-7
-------
24
10 x
0,02 0.04 0.06 0.08 0.1
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (MG/L)
FIGURE VI11-6 DISTRIBUTION.OF NEW AND OLD MEDIAN PHOSPHORUS
CONCENTRATIONS FOR LAKES IN AREA 2, OPTION 5
VIII-8
-------
120 -1
100 -
CD
o;
UJ
CQ
-------
120-1
100-
80-
60-
20-
0.02 0,04 0,06 0,08 0.1
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (MG/L)
FIGURE VI11-8 DISTRIBUTION OF NEW AND OLD MEDIAN PHOSPHORUS
CONCENTRATIONS FOR LAKES IN AREA 4, OPTION 5
VIII-10
-------
120-1
100-
80-
60-
-------
120i
100-
oo
UJ
3
80-
60-
0.02 0.04 O.OG 0.08 0.01
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (NG/L)
FIGURE VI11-10 DISTRIBUTION OF NEW AND OLD MEDIAN PHOSPHORUS
CONCENTRATIONS FOR LAKES IN AREA 6, OPTION 5
VIII-12
-------
120 -i
100-
LU
•^.
UJ
CO
80-
60-
-------
Table VIII-1
Effect of Control Option 5 on In Situ
Total Phosphorus Concentrations
Region
1
2
3
4
5
6
7
All
Number
of
Lakes
120
108
56
32
83
41
53
493
Original Loading
Concentration, mg/5,
Minimum
0.004
0.006
0.007
0.011
0.010
0.006
0.007
0.004
Mean
0.141
0.086
0.041
0.121
0.058
0.034
0.054
0.084
Maximum
1.525
0.865
0.143
0.489
0.424
0.115
0.371
1.525
New Loading
(60% Nonpoint Source Reduction)
Concentration, mg/H
Minimum
0.002
0.002
0.003
0.005
0.005
0.003
0.003
0.002
Mean
0.115
0.054
0.023
0.054
0.028
0.016
0.027
0.055
Maximum
1.517
0.651
0.121
0.237
0.170
0.069
0.152
1.517
Table VIII-2
Number and Fraction of Lakes with Median Phosphorus
Concentrations Less Than 0.025 mg/£
Region
1
2
3
4
5
6
7
All
Number
of
Lakes
120
108
56
32
83
41
53
493
Lakes with Total P
<0.025 mg/£
Old
#
37
29
23
3
24
20
24
160
%
31
27
41
9
29
49
45
32
New
#
57
49
38
9
49
33
38
273
%
48
45
68
28
59
80
72
55
Change
(New - Old)
#
20
20
15
6
25
13
14
113
%
17
18
27
19
30
31
27
23
VIII-14
-------
SECTION IX
CONTROL OPTION 6
20% NONPOINT SOURCE AND 80% MUNICIPAL CONTROL
This section describes the results of analyzing the effects of a
20% reduction in nonpoint source plus an 80% reduction in municipal
treatment plant phosphorus loading. The mass loadings of phosphorus
from "rivers" and "direct runoff" were reduced by 20%. The mass load-
ings from municipal treatment plants were reduced by 80%. Figure IX-1
illustrates the distribution of old and new total phosphorus loading
rates. It is evident that this reduction in phosphorus loads has an
effect on total loading rates.
METHODS
The procedures followed were as described in Section III. After
computing a new total phosphorus load to each lake, the predicted
j_n_ situ steady-state concentration of phosphorus was computed accord-
ing to the procedures described in Section III. Chlorophyll-a_
concentrations and Secchi disc depths were subsequently computed for
each lake. All computed values represent annual averages for each lake
at steady-state.
RESULTS
Values of old and new total phosphorus loading, average in situ
phosphorus concentration, chlorophyll-a_ concentration and Secchi disc
depth for each lake are tabulated in Appendix B-6, both by geographical
area (Figure 11-13, page 11-30) and for all lakes combined.
IX-1
-------
— base case
20% nonpoint
source reduction
+80% municipal
phosphorus reduction
10
PHOSPHORUS LOADING (KG/YR)
10
7
FIGURE IX-1
DISTRIBUTION OF NEW AND OLD
PHOSPHORUS LOADING RATES,
OPTION 6
IX-2
-------
Figures IX-2 through IX-4 show the distribution of parameter
values for the base case (NES data) and the control option for all
lakes. New and old median phosphorus concentrations for the lakes
within each of the seven geographical areas are shown in Fiqures
IX-5 through IX-11.
Because the chlorophyll-a_ levels and Secchi disc depths were
relatively insensitive to changed phosphorus loading the following
discussion is limited to effects of the control option on phosphorus
concentrations.
For all 493 lakes used in the data base the effect of a 20%
nonpoint source plus 80% municipal phosphorus reduction is shown in
Figure IX-2. The mean value of predicted phosphorus concentration
is 0.049 mg/ji compared to 0.084 with no control. The number of lakes
with a median phosphorus concentration less than 0.025 mg/£ increased
from 160 to 219.
Table IX-1 summarizes the results for all lakes and fcr subsets
of lakes grouped by geographical area. Table IX-2 summarizes the
number and fraction of lakes with median phosphorus concentrations
less than 0.025 mg/£.
IX-3
-------
HI 1
0.2 0.4 0.6 0.8 1.0 >1.0
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (MG/L)
500-!
UJ
•^.
3
400-
300-
CO
§ 200-1
100-
0.02 0.04 0.06 0.08 0.10
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (MG/L)
97
SB x
FIGURE IX-2 DISTRIBUTION OF NEW AND OLD MEDIAN PHOSPHORUS
CONCENTRATIONS, OPTION 6
IX-4
-------
oo
LU
5001
400-
g 300
CQ
5 200-
100-
9
9 x
20
-ii-
10 60 80
MEAN CHLOROPHYLL-A (yG/L)
100
>100
500n
00
300-
p 200-
100-
4.0
100
95 x
8,0 12.0 16.0
MEAN CHLOROPHYLL-A (yG/L)
20.0
>20.0
FIGURE IX-3
DISTRIBUTION OF NEW AND OLD MEAN
CHLOROPHYLL-A CONCENTRATIONS, OPTION 6
IX-5
-------
500
300 --4
eg
:5
£ 200
100H
"T?
10
-10
~£(F " " yf
6:o -• • - >b.o
;vlX-6
-------
120 n
100-
80-
LU
CD
= 60-
10-
20-
36
20 X
Option 6
base case
Hl-
0.02 0.04 0.06 0.08 0.1
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (MG/L)
FIGURE IX-5
DISTRIBUTION OF NEW AND O,LD MEDIAN PHOSPHORUS
CONCENTRATIONS FOR LAKES IN AREA 1, OPTION 6
•IX-7
-------
24
11 x
0.02 0.04 0.06 0.08 0.1
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (MG/L)
FIGURE IX-6 DISTRIBUTION OF NEW AND OLD MEDIAN PHOSPHORUS
CONCENTRATIONS FOR LAKES IN AREA 2, OPTION 6
IX-8
-------
120 -|
100 -
CO
LU
3 80 -
Ll-
CS
UJ
CO
I 60
20 -
-it-
0.02 0.04 0.06 0.08 0.1
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (MG/L)
FIGURE. IX-7
DISTRIBUTION OF NEW AND OLD MEDIAN PHOSPHORUS
CONCENTRATIONS FOR LAKES IN AREA,3, OPTION 6
IX-9
-------
120 i
100-
80-
CD
60-
40-
20 -\
ii
10 x
0.02 0.04 0.06 0.08 0.1
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (KG/L)
FIGURE IX-8 DISTRIBUTION OF NEW AND OLD MEDIAN PHOSPHORUS
CONCENTRATIONS FOR LAKES IN AREA 4, OPTION 6
IX-10
-------
120i
100-
80-
O
a:
UJ
CQ
-------
120-1
100-
oo
UJ
i^
3
CQ
«=C
O
80-
60-
10-
20-
0.02 0.04 O.OG 0.08 0.01
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (M6/L)
FIGURE IX-10
DISTRIBUTION OF NEW AND OLD MEDIAN PHOSPHORUS
CONCENTRATIONS FOR LAKES IN AREA 6, OPTION 6
IX-12
-------
120 n
ioo H
GO
LI-
CD
Di
UJ
CQ
80 -J
= 60 H
10 H
20 H
6
S
0.02 0.04 0.06 0.08 1.0
MEDIAN IN-LA'KE PHOSPHORUS CONCENTRATION (MG/L)
FIGURE IX-11
DISTRIBUTION OF NEW AND OLD MEDIAN PHOSPHORUS
CONCENTRATIONS FOR LAKES IN AREA 7, OPTION 6
IX-13
-------
Table IX-1
Effect of Control Option 6 on In Situ
Total Phosphorus Concentrations
Region
1
2
3
4
5
6
7
All
Number
of
Lakes
120
108
56
32
83
41
53
493
Original Loading
Concentration, mg/£
Minimum
0.004
0.006
0.007
0.011
0.010
0.006
0.007
0.004
Mean
0.141
0.086
0.041
0.121
0.058
0.034
0.054
0.084
Maximum
1.525
0.865
0.143
0.489
0.424
0.115
0.371
1.525
New Loading
(202 Nonpoint & 80% Municipal Reduction)
Concentration, mg/i
Minimum
0.003
0.004
0.006
0.009
0.006
0.005
0.006
0.003
Mean
0.060
0.052
0.026
0.095
0.043
0.026
0.040
0.049
Maximum
0.781
0.419
0..090
0.352
0.339
0.082
0.298
0.781
Table IX-2
Number and Fraction of Lakes with Median Phosphorus
Concentrations Less Than 0.025 mg/£
Region
1
2
3
4
5
6
7
All
Number
of
Lakes
120
108
56
32
83
41
53
493
Lakes with Total P
<0.025 mg/£
Old
#
37
29
23
3
24
20
24
160
%
31
27
41
9
29
49
45
32
New
#
58
39
30
4
36
24
28
219
%
48
36
54
13
43
59
53
44
Change
(New - Ol^d)
#
21
10
7
1
12
4
4
59
%
17
9
13
4
14
10
8
12
IX-14
-------
SECTION X
CONTROL OPTION 7
40% NONPOINT SOURCE AND 80% MUNICIPAL CONTROL
This section describes the results of analyzing the effects of a
40% reduction in nonpoint source plus an 80% reduction in municipal
treatment plant phosphorus loading. The mass loadings of phosphorus
from "rivers" and "direct runoff" were reduced by 40%. The mass load-
ings from municipal treatment plants were reduced by 80%. Figure X-l
illustrates the distribution of old and new total phosphorus loading
rates. It is evident that this reduction in phosphorus loads has an
effect on total loading rates.
METHODS
The procedures followed were as described in Section III. After
computing a new total phosphorus load to each lake, the predicted
JJT_ situ steady-state concentration of phosphorus was computed accord-
ing to the procedures described in Section III. Chlorophyll-a^ con-
centrations and Secchi disc depths were subsequently computed for each
lake. All computed values represent annual averages for each lake at
steady-state.
RESULTS
\ Values of old and new total phosphorus loading, average in situ
phosphorus concentration, chlorophyll-a concentration and Secchi disc
depth Nor each lake are tabulated in Appendix B-7, both by geographical
areas (Figure 11-13, page 11-30) and for all lakes combined.
X-l
-------
10
PHOSPHORUS LOADING (KG/YR)
FIGURE X-l DISTRIBUTION OF NEW AND OLD
PHOSPHORUS LOADING RATES,
OPTION 7
X-2
-------
Figures X-2 through X-4 show the distribution of parameter values
for the base case (NES data) and the control option for all lakes. New
and old median phosphorus concentrations for the lakes within each of
the seven geographical areas are shown in Figures X-5 through X-ll.
Because the chlorophyll-^ levels and Secchi disc depths were
relatively insensitive to changed phosphorus loading the following dis-
cussion is limited to effects of the control option on phosphorus con-
centrations.
For all 493 lakes used in the data base the effect of a 40% nonpoint
source plus 80% municipal phosphorus reduction is shown in Figure X-2.
The mean value of predicted phosphorus concentration is 0.039 mg/£
compared to 0.084 with no control. The number of lakes with median
phosphorus concentrations less than 0.025 mg/a increased from 160
to 264.
Table X-l summarizes the results for all lakes and for subsets of
lakes grouped by geographical area. Table X-2 summarizes the number
and fraction of lakes with median phosphorus concentrations less than
0.025 mg/fc.
X-3
-------
0.2 0.4 0.6 0.8 1.0
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (MG/L)
97
0 0.02 0.04 0.06 0.08 0.10
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (MG/L)
FIGURE X-2
DISTRIBUTION OF NEW AND OLD MEDIAN PHOSPHORUS
CONCENTRATIONS, OPTION 7
X-4
-------
500
10 60 80
MEAN CHLOROPHYLL-A (yG/L)
100
g
7
>100
4.0
8.0 12,0 16.0
MEAN CHLOROPHYLL-A (yG/L)
20.0
ino
93 :
>20.0
FIGURE X-3
DISTRIBUTION OF NEW AND OLD MEAN
CHLOROPHYLL-A CONCENTRATIONS, OPTION 7
X-5
-------
500 n
oo 400 -
LU
3
u_
CD
300-
CQ
200-
100 -
1.0 2.0 3,0 4.0
MEAN SECCHI DISC (M)
5.0
10
10
11 1
6.0
>6.0
FIGURE X-4 DISTRIBUTION OF NEW AND OLD MEAN SECCHI Disc
DEPTHS, OPTION 7
X-6
-------
oo
o
QL
LU
120-1
100-
80-
60-
40-
20-
36
16 X
0.02 0.04 0.06 0.08 0.1 --0.1
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (MG/L)
FIGURE X-5
DISTRIBUTION OF NEW AND OLD MEDIAN PHOSPHORUS
CONCENTRATIONS FOR LAKES IN AREA 1, OPTION 7
X-7
-------
lOO-i
CO
UJ
03
80-
60-
10-
20-
24
B x
0,02 0.04 0.06 0.08 0.1
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (HG/L)
FIGURE X-6
DISTRIBUTION OF NEW AND OLD MEDIAN PHOSPHORUS
CONCENTRATIONS FOR LAKES IN AREA 2, OPTION 7
X-8
-------
120 n
100 -\
80 H
ce:
LU
CQ
SE 60 -\
20 J
0.02 0.04 0,06 0.08 0.1
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (MG/L)
FIGURE X-7 DISTRIBUTION OF NEW AND OLD MEDIAN
CONCENTRATIONS FOR LAKES IN AREA 3, OPTION 7
X-9
-------
120-i
100-
O
Qi
UJ
CQ
-------
120-i
100-
CO
LiJ
0,1
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (MG/L)
FIGURE X-9
DISTRIBUTION OF NEW AND OLD MEDIAN PHOSPHORUS
CONCENTRATIONS FOR LAKES IN AREA 5, OPTION 7
x-n
-------
12Ch
10CH
oo
LU
i^
-------
120 -i
100-
GO
UJ
80-
CO
60-
<£.
O
20 -
0.02 0.04 0.06 0.08 1.0
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (MG/L)
FIGURE X-ll
DISTRIBUTION OF NEW AND OLD MEDIAN PHOSPHORUS
CONCENTRATIONS FOR LAKES IN AREA 7, OPTION 7
X-13
-------
1201
iocH
CO
LU
i«i
-------
120 i
100-
GO
UJ
_
o
a:
UJ
CQ
80-
60-
20-
6
4
0.02 0.04 0.06 0.08 1.0
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (MG/L)
FIGURE X-ll
DISTRIBUTION OF NEW AND OLD MEDIAN PHOSPHORUS
CONCENTRATIONS FOR LAKES IN AREA 1, OPTION 7
X-13
-------
Table X-l
Effect of Control Option 7 on In Situ
Total Phosphorus Concentrations
Region
1
2
3
4
5
6
7
All
Number
of
Lakes
120
108
56
32
83
41
53
493
Original Loading
Concentration, mg/£
Minimum
0.004
0.006
0.007
0.011
0.010
0.006
0.007
0.004
Mean
0.141
0.086
0.041
0.121
0.058
0.034
0.054
0.084
Maximum
1.525
0.865
0.143
0.489
0.424
0.115
0.371
1.525
New Loading
[ 402 Nonpoint & 80" Municipal Reduction )
Concentration, mg/5.
Minimum
0.003
0.003
0.004
0.007
0.005
0.004
0.004
0.003
Mean
0.052
0.040
0.020
0.072
0.033
0.020
0.031
0.039
Maximum
0.767
0.337
0.067
0.267
0.254
0.067
0.225
0.767
Table X-2
Number and Fraction of Lakes with Median Phosphorus
Concentrations Less Than 0.025 mg/£
Region
1
2
3
4
5
6
7
All
Number
of
Lakes
120
108
56
32
83
41
53
493
Lakes with Total P
<0.025 mg/Jl
Old
#
37
29
23
3
24
20
24
160
%
31
27
41
9
29
49
45
32
New
#
65
48
38
5
47
28
33
264
%
54
44
68
16
57
68
62
53
Change
(New - Old)
#
28
19
15
2
23
8
9
104
% .
23
17
27
7
28
19
17
21
X-14
-------
SECTION XI
CONTROL OPTION 8
60% NONPOINT SOURCE AND 80% MUNICIPAL CONTROL
This section describes the results of analyzing the effects of a
60% reduction in nonpoint source plus an 80% reduction in municipal
treatment plant phosphorus loading. The mass loadings of phosphorus
from "rivers" and "direct runoff" were reduced by 60%. The mass load-
ings from municipal treatment plants were reduced by 80%. Figure XI-1
illustrates the distribution of old and new total phosphorus loading
rates. It is evident that this reduction in phosphorus loads has a
marked effect on total loading rates.
METHODS
The procedures followed were as described in Section III. After
computing a new total phosphorus load to each lake, the predicted
iQ. situ steady-state concentration of phosphorus was computed accord-
ing to the procedure described in Section III. Chiorophyll-a_ con-
centrations and Secchi disc depths were subsequently computed for each
lake. All computed values represent annual averages for each lake at
steady-state.
RESULTS
Values of old and new total phosphorus loading, average in situ
phosphorus concentration, chlorophyll-^ concentration and Secchi disc
depth for each lake are tabulated in Appendix B-8, both by geographical
area (Figure 11-13, page 11-30) and for all lakes combined.
XI-1
-------
500
10
PHOSPHORUS LOADING (KG/YR)
FIGURE XI-1 DISTRIBUTION OF NEW AND OLD
PHOSPHORUS LOADING RATES,
OPTION 8
XI-2
-------
Figures XI-2 through XI-4 show the distribution of parameter
values for the base case (NES data) and the control option for all
lakes. New and old median phosphorus concentrations for the lakes
within each of the seven geographical areas are shown in Figures
XI-5 through XI-11.
Because the chlorophyll-a_ levels and Secchi disc depths were
relatively insensitive to changed phosphorus loading, the following
discussion is limited to effects of the control option on phosphorus
concentrations.
For all 493 lakes used in the data base the effect of a 60%
nonpoint source and 80% municipal phosphorus reduction is shown in
Figure XI-2. The mean value of predicted phosphorus concentration
is 0.029 mg/H compared to 0.084 with no control. The number of lakes
with median phosphorus concentrations less than 0.025 mg/£ increased
from 160 to 336.
Table XI-1 summarizes the results for all lakes and for subsets
of lakes grouped by geographical area. Table XI-2 summarizes the
number and fraction of lakes with median phosphorus concentrations
less than 0.025 mg/£.
XI-3
-------
0.2 0.4 0.6 0.8 1,0
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (MG/L)
97
29 X
U 0.02 0.04 0.06 0.08 0.10
MEDIAN .IN-LAKE PHOSPHORUS CONCENTRATION (MG/L)
FIGURE XI-2
DISTRIBUTION OF NEW AND OLD MEDIAN PHOSPHORUS
CONCENTRATIONS, OPTION 8
XI-4
-------
500
oo
UJ
3
u_
o
CQ
400 -
300 -
o 200 -
100-
20
40 60 80
MEAN CHLOROPHYLL-A (yG/L)
100
9
H X
HI 1
>100
CO
LU
^i
5
u_
£
CQ
500n
100 H"
300-
P 200 H
100-
4.0
8.0 12.0 16.0
MEAN CHLOROPHYLL-A (uG/L)
20.0
FIGURE XI-3
100
87 X
>20.0
DISTRIBUTION OF NEW AND OLD MEAN
CHLOROPHYLL-A CONCENTRATIONS, OPTION 8
-------
500 -|
3.0
MEAN SECCHI DISC (M)
10
10 x
6.0
>b.U
FIGURE XI-4 DISTRIBUTION OF NEW AND OLD MEAN SECCHI Disc
DEPTHS, OPTION 8
XI-6
-------
co
CD
100-
80-
60-
20-
36
12 X
Option 8
base case
0.02 0.04 0.06 0.08 0.1
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (HG/LV
FIGURE XI-5
DISTRIBUTION OF NEW AND OLD MEDIAN PHOSPHORUS
CONCENTRATIONS FOR LAKES IN AREA 1, OPTION 8
XI-7
-------
24
3 x
0.02 0.04 0.06 0.08 0.1
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (M6/L)
FIGURE XI-6
DISTRIBUTION OF NEW AND OLD MEDIAN PHOSPHORUS
CONCENTRATIONS FOR LAKES IN AREA 2, OPTION 8
XI-8
-------
120 -i
100
o
o;
LU
eg
3
80 -
60-
20-
0.02 0.04 0.06 0.08 0.1
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (MG/L)
FIGURE XI-7
DISTRIBUTION OF NEW AND OLD MEDIAN PHOSPHORUS
CONCENTRATIONS FOR LAKES IN AREA 3, OPTION 8
XI-9
-------
120-1
100-
00
CQ
•=c
CD
80-
60-
20-
11
5 x
0.02 0.04 0.06 0.08 0.1
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (MG/L)
FIGURE XI-8
DlStRIBUTION OF NEW AND Ol_D MEDIAN PHOSPHORUS
CONCENTRATIONS FOR LAKES IN AREA 4, OPTION 8
XI-10
-------
120 n
100-
GO
UJ
-a:
u_
O
a;
LiJ
ca
80-
60-
20-
12
1 x
-Hh-
0.02 0.04 0.06 0.08 0.1 >0,1
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (MG/L)
FIGURE XI-9
DISTRIBUTION OF NEW AND OLD MEDIAN PHOSPHORUS
CONCENTRATIONS FOR LAKES IN AREA 5, OPTION 8
xi-n
-------
120-1
100-
00
UJ
«ac
Ll-
CS
ce:
LU
CO
80-
60-
40-
20-
0.02 0.04 O.OG 0.08 0.01
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (MG/L)
FIGURE XI-10
DISTRIBUTION OF NEW AND OLD MEDIAN PHOSPHORUS
CONCENTRATIONS FOR LAKES IN AREA 6, OPTION 8
XI-12
-------
120-,
100-
GO
ex.
UJ
CO
80-
60-
20-
6
2
0.02 0.04 0.06 0.08 1.0
MEDIAN IN-LAKE PHOSPHORUS CONCENTRATION (F1G/L)
FIGURE XI-11
DISTRIBUTION OF NEW AND OLD MEDIAN PHOSPHORUS
CONCENTRATIONS FOR LAKES IN AREA 1, OPTION 8
XI-13
-------
Table XI-1
Effect of Control Option 8 on In Situ
Total Phosphorus Concentrations
Region
1
2
3
4
5
6
7
All
Number
of
Lakes
120
108
56
32
83
41
53
493
Original Loading
Concentration, mg/5,
Minimum
0.004
0.006
0.007
0.011
0.010
0.006
0.007
0.004
Mean
0.141
0.086
0.041
0.121
0.058
0.034
0.054
0.084
Maximum
1.525
0.865
0.143
0.489
0.424
0.115
0.371
1.525
New Loading
(601- Nonpoint & 80% Municipal Reduction)
Concentration, mg/£
Minimum
0.002
0.002
0.003
0.005
0.004
0.003
0.003
0.002
Mean
0.044
0.030
0.014
0.050
0.023
0.014
0.022
0.029
Maximum
0.753
0.256
0.045
0.183
0.170
0.052
0.152
0.753
Table XI-2
Number and Fraction of Lakes with Median Phosphorus
Concentrations Less Than 0.025 mg/£
Region
1
2
3
4
5
6
7
All
Number
of
Lakes .
120
108
56
32
83
41
53
493
Lakes with Total P
<0.025 mg/£
Old
#
37
29
23
3
24
20
24
160
%
31
27
41
9
29
49
45
32
New
#
77
64
49
10
61
34
41
336
%
64
59
88
31
73
83
77
68
Change
(New - Old)
#
40
35
26
7
37
14
17
176
%
33
32
47
22
44
34
32
36
XI-14
-------
REFERENCES
All urn, M.O., Glesser, R.E., and Gakstatter, J.H. 1977. An Evaluation
of the National Eutrophication Survey Data. Working Paper No. 900.
Booman, K.A. 1978. "The Impact of Detergents on Phosphate Removal."
Annual American Chemical Society Meeting, Miami.
Clarke, G.L. 1954. Elements of Ecology. Wiley. 192-193.
Dillon, P.J. 1974. "A manual for calculating the capacity of a lake
for development". Ontario Ministry of the Environment.
Dillon, P.J. and Rigler, F.H. 1974. A test of a simple nutrient
budget model predicting the phosphorus concentrations in lake
water. J. Fish. Res. Bd. Can. 31:1771-1778.
Dillon, P.J. and Rigler, F.H. 1975. A simple method for predicting
the capacity of a lake for development based on lake trophic
status. J. Fish. Res. Bd. Can. 32:1519-1531.
Jones, J.R. and Bachmann, R.W. 1976. Prediction of phosphorus and
chlorophyll level in lakes. J. Water Poll. Control Fed.
48:2176-2182.
Larsen, D.P. and Mercier, H.T. 1975. Lake phosphorus loading graphs:
an alternative. Eutrophication and Lake Restoration Branch, EPA,
Working Paper No. 174.
Lee, G.F., R t, W. and Jones, R.A. 1978. Eutrophication of water bodies:
Insights for an age old problem. Env. Sci. and Tech. 12(8):900-908.
Lorenzen, M.W. 1972. "The role of mixing in eutrophication control.
Ph.D. thesis, Harvard University.
Lorenzen, M.W. 1978. "Phosphorus Models and Eutrophication". In:
R. Mitchell, ed. Water Pollution Microbiology, Vol. 2. Wiley.
31-50.
Lorenzen, M.W. and Mitchell, R. 1975. An evaluation of artificial
destratification for control of algal blooms. J. Am. Water Works
Assoc. 6:373-376.
Lorenzen, M., Smith,
-------
REFERENCES (continued)
Lund, J.W.G. 1971. Primary production. Water Treatment and Examina-
tion. 19:332-358.
Region V Phosphorus Committee. 1977. Detergent phosphate ban.
EPA 905/2-77-003. Chicago, Illinois.
Sakamoto, M. 1966. Primary production by phytoplankton community in
some Japanese lakes and its dependence on lake depth. Archives
of Hydrobiology. 62:1-28.
U.S. Environmental Protection Agency. 1974a. National Eutrophication
Survey methods for lakes sampled in 1972. National Eutrophication
Survey Working Paper No. 1. U.S. Environmental Protection Agency,
National Eutrophication Research Program, Coravallis, Oregon. 40 pp.
. 1974b. The relationships of phosphorus and nitrogen to the
trophic state of northeast and north-central lakes and reservoirs.
National Eutrophication Survey Working Paper No. 23. U.S. Environ-
mental Protection Agency, National Eutrophication Research Program,
Corvallis, Oregon.
U.S. Environmental Protection Agency. 1975a. National Eutrophication
Survey methods, 1973-1976. National Eutrophication Survey Working
Paper No. 175. U.S. Environmental Protection Agency, National
Eutrophication Research Program, Corvallis, Oregon. 91 pp.
1975b. Compendium of lake and reservoir data collected by
the National Eutrophication Survey in the northeast and north-
central United States. MES Working Paper No. 474.
. 1978. Compendium of lake and reservoir data collected by
. the National Eutrophication Survey in the eastern, north-central
and southeastern United States. NES Working Paper No. 475.
. 1978. Compendium of lake and reservoir data collected by
the National Eutrophication Survey in the central United States.
NES Working Paper No. 476.
. 1978. Compendium of lake and reservoir data collected by
the National Eutrophication Survey in the western United States.
MES Working Paper No. 477.
Welch, J. 1978. Personal communication.
-------
X
Q
z
LU
d.
a.
-------
APPENDIX A
NATIONAL EUTROPHICATION SURVEY DATA
USED IN EVALUATION OF PHOSPHORUS CONTROL OPTIONS
1972 THROUGH 1975
Prepared by Tetra Tech, Inc.
September 15, 1978
Note: A portion of Appendix A which lists the
data used is included here for easy
reference. The complete Appendix is
included in the microfich attached to
the back cover of the report.
-------
TABLE OF CONTENTS
State Codes
Miscellaneous Codes
Lake Names and Codes
Locations of Lakes in 1972-1975 Surveys
Lake Data 1972-1975
Phosphorus Loading 1972-1975
Computed Parameters 1972-1975
-------
STATE CODES
A5
-------
STATE CODES
01 ALABAMA
02 ALASKA
04 ARIZONA
05 ARKANSAS
06 CALIFORNIA .
08 COLORADO
09 CONNECTICUT
10 DELAWARE
12 FLORIDA
13 GEORGIA
15 HAWAII
16 IDAHO
17 ILLINOIS
18 INDIANA
19 IOWA
20 KANSAS
21 KENTUCKY
22 LOUISIANA
23 MAINE
24 MARYLAND
25 MASSACHUSETTS
26 MICHIGAN
27 MINNESOTA
28 MISSISSIPPI
29 MISSOURI
30 MONTANA
31 NEBRASKA
32 NEVADA
33 NEW HAMPSHIRE
34 NEW JERSEY
35 NEW MEXICO
36 NEW YORK
37 NORTH CAROLINA "
38 NORTH DAKOTA
39 OHIO
40 OKLAHOMA
41 OREGON
42 PENNSYLVANIA
44 RHODE ISLAND
45 SOUTH CAROLINA
46 SOUTH DAKOTA
47 TENNESSEE
48 TEXAS
49 UTAH
50 VERMONT
51 VIRGINIA
53 WASHINGTON
54 WEST VIRGINIA
55 WISCONSIN
56 WYOMING
11 DISTRICT OF COLUMBIA
14 GUAM
43 PUERTO RICO
52 VIRGIN ISLANDS
A6
-------
MISCELLANEOUS CODES
A7
-------
Retention Time Codes
Trophic State Codes
1 - RT < 3 months
2-3 months < RT < 12 months
3 - 12 months < RT < 36 months
4 - RT > 36 months
Depth Codes
1 - Depth < 5 meters
2 - 5 < Depth < 20 meters
3 - Depth > 20 meters
Type Codes
I - Impound
N - Natural
0 - Oligotrophic
M - Mesotrophic
E - Eutrophic
HE - Hypereutrophic
OM - Oligotrophic -- Mesotropf
OE - Oligotrophic -- Eutrophic
OH - Oligotrophic — Hypereutrophic
ME - Mesotrophic — Eutrophic
MH - Mesotrophic — Hypereutrophic
EH - Eutrophic — Hypereutrophic
LM - Oligo - Mesotrophic
MU - Meso - Eutrophic
OU - Oligo - Eutrophic
A8
-------
LAKE NAMES AND CODES
X X X X
X
X X
•** X X
XXX
A9
-------
LAKE NAMES AND CODES
0901
0904
0905
0910
0911
0912
2304
2306
2308
2309
2310
2311
2312
2313
2314
2502
2503
2507
2508
2513
2603
2606
2609
2617
2618
2629
2631
2643
2648
2659
2673
2683
2685
2688
I
I
I
I
I
I
I
N
N
N
N
N
N
N
N
N
I
I
I
I
I
N
I
N
N
I
N
N
N
N
I
N
N
N
E
E
HE
E
E
E
E
M
M
0
0
0
E
M
0
HE
E
HE
E
E
E
E
E
0
E
E
HE
E
HE
E
E
E
E
E
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
176
179
180
181
181
181
3
4
8
2
6
5
9
7
5
220
27
223
221
219
182
183
184
188
189
193
194
199
200
203
209
215
216
217
Lake Name
ASPINOOK POND
EAGLEVILLE LAKE
HANOVER POND
LAKE ZOAR
LAKE LILLINONAH
LAKE HOUSATONIC
ESTES LAKE
LONG LAKE
MATTAWAMKEAG LAKE
MOOSEHEAD LAKE
RANGELEY LAKE
SEBAGO LAKE
SEBASTICOOK LAKE
LONG LAKE
BAY OF NAPLES
HAGER POND
HARRIS POND
WOODS POND
MATFIELD IMPOUNDMENT
HUDSON IMPOUNDMENT
LAKE ALLEGAN
BARTON LAKE
BELLEVILLE LAKE
LAKE CHARLEVOIX
LAKE CHEMUNG
FORD LAKE
FREMONT LAKE
KENT LAKE
MACATAWA LAKE
MUSKEGON LAKE
ROSS RESERVOIR
THORNAPPLE LAKE
UNION LAKE
WHITE LAKE
County
NEW LONDON, WINDOM
TOLLAND
NEW HAVEN
LITCHFIELD, NEW HAVEN
FAIRFIELD
NEWHAVEN, FAIRFIELD
YORK
CUMBERLAND
AROOSTOOK
PISCATAQUIS, SOMERSET
FRANKLIN
CUMBERLAND
PENOBSCOT
AROOSTOOK
CUMBERLAND
MIDDLESEX
PROVIDENCE, (RI); WORCHESTER, (MA)
BERKSHIRE
PLYMOUTH
MIDDLESEX, WORCHESTER
ALLEGAN
KALAMAZOO
WAYNE
CHARLEVOIX
LIVINGSTON
WASHTENAW
NEWAYGO
'OAKLAND, LIVINGSTON
OTTAWA
MUSKEGON
GLADWIN
BARRY
BRANCH
MUSKEGON
A10
-------
LAKE NAMES AND CODES
2691
2692
2694
2695
2696
2699
27A1
27A2
27A5
27A6
27A7
27B1
27B2
27B3
27B4
27CO
•27C1
27C2
2702
2705
2709
2711
2712
2713
2715
2716
2719
2725
2737
2739
2746
2750
2756
2757
N
N
N
N
N
N
N
N
I
I
I
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
E
E
0
0
E
E
E
E
E
E
E
E
M
E
ME
E
E
E
E
E
E
E
E
E
M
E
E
E
E
E
M
E
E
E
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
202
211
191
195
196
213
135
136
137
127
122
133
101
117
96
81
84
115
80
83
85
86
87
88
92
93
94
97
102
103
105
108
111
112
Lake Name
MONA LAKE
LONG LAKE
CRYSTAL LAKE
HIGGINS LAKE
HOUGHTON LAKE
STRAWBERRY LAKE
LAKE WINONA
WOLF LAKE
ZUMBRO LAKE
SPRING LAKE
LAKE ST. CROIX
WAGONGA LAKE
GREEN LAKE
NEST LAKE
LAKE DARLING
LAKE ANDRUSIA
LAKE BEMIDJI
MUD LAKE
ALBERT LEA LAKE
BARTLETT LAKE
BIG STONE
BLACKDUCK LAKE
BLACKHOOF LAKE
BUFFALO LAKE
CASS LAKE
CLEARWATER LAKE
COKATO LAKE
ELBOW LAKE
GULL LAKE (SOUTH BASIN)
HERON LAKE
LEECH LAKE
MADISON LAKE
MASHKENODE LAKE
MCQUADE LAKE
County
MUSKEGON
ST JOSEPH
MONTCALM
ROSCOMMON
ROSCOMMON
LIVINGSTONE
DOUGLAS
BELTRAMI, HUBBARD
OLMSTED, WABASHA
DAKOTA, WASHINGTON
WASHINGTON, (MN); ST. CROIX, PIERCE, (WI)
KANDIYOHI
KANDIYOHI
KANDIYOHI
DOUGLAS
BELTRAMI
BELTRAMI
ITASCA
FREEBORN
KOOCHICHING
BIG STONE, (MN); ROBERTS, GRANT, (SD)
BELTRAMI
CROW WING
WRIGHT
BELTRAMI, CASS
WRIGHT, STEARNS
WRIGHT
ST. LOUIS
CASS, CROW WING
JACKSON
CASS
BLUE EARTH
ST. LOUIS
ST. LOUIS
All
-------
LAKE NAMES AND CODES
2761
2765
2776
2782
2783
2788
2793
3302
3303
3305
3306
3604
3605
3606
3608
3611
3617
3632
3633
3635
3637
3639
3640
4402
4403
5001
5002
5005
5007
5008
5010
5011
5509
5513
N
N
N-
N
N
N
N
I
N
I
I
N
I
N
N
N
N
N
N
N
I
N
N
I
I
N
I
I
I
N
I
I
N
N
E
M
E
E
E
M
E
E
0
E
E
0
E
M
M
E
0
M
E
M
E
E
E
E
E
M
E
M
E
E
E
M
E
E
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
114
118
123
125
126
129
131
14
11
13
12
149
150
151
153
157
160
167
168
170
172
156
162
28
29
154
15
20
16
19
17
18
34
36
Lake Name
LAKE MINNEWASKA
PELICAN LAKE
ST. LOUIS BAY
SILVER LAKE
SIX MILE LAKE
SWAN LAKE
TROUT LAKE
POWDER MILL POND
LAKE WINNIPESAUKEE
KELLYS FALLS POND
GLEN LAKE
CANADIAGUA
CANNONSVILLE RESERVOIR
CARRY FALLS RESERVOIR
CAYUGA LAKE
CROSS LAKE
KEUKA LAKE
SACANDAGA RESERVOIR
SARATOGA LAKE
SENECA LAKE
SWINGING BRIDGE RES.
CONESUS LAKE
LOWER ST. REGIS '
SLATERSVILLE RESERVOIR
TURNER RESV.-CENTRAL PND
LAKE CHAMPLAIN
CLYDE POND
HARRIMAN RESERVOIR
LAKE LAMOILLE
LAKE MEMPHREMAGOG
ARROWHEAD MOUNTAIN LAKE
WATERBURY RESERVOIR
BUTTERNUT LAKE
DELAVAN LAKE
County
POPE
ST. LOUIS
ST. LOUIS, (MN); DOUGLAS, (WI)
MCLEOD
ST. LOUIS
ITASCA
ITASCA
HILLSBOROUGH
BELKNAP, CARROLL
HILLSBOROUGH
HILLSBOROUGH
ONTARIO, YATES
DELAWARE
ST. LAWRENCE
CAYUGA, SENECA, TOMPKINS
CAYUGA, ONONDAGA
YATES, STEUBEN
FULTON, SARATOGA
SARATOGA
SCHUYLER
SULLIVAN
LIVINGSTON
FRANKLIN
PROVIDENCE
PROVIDENCE, (RI); BRISTOL, (MA)
VT, AND NY AREA
ORLEANS
WINDHAM
LOMOILLE
ORLEANS
CHITTENDEN, FRANKLIN
WASHINGTON, LAMOILLE
PRICE, ASHLAND
WALWORTH
A12
-------
LAKE NAMES AND CODES
5519
5520
5522
5531
5538
5539
5541
5546
5548
5550
5555
5556
5559
5564
5565
5570
5574
0101
0104
0105
0107
0112
0115
1005
1007
1008
1009
1010
1301
1302
1303
1304
1309
1310
N
N
I
N
N
N
I
N
N
N
I
I
N
N
I
N
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
M
E
E
E
E
E
E
E
E
E
E
E
HE
M
E
E
M
E
E
E
M
E
E
E
E
E
E
E
E
E
M
ME
E
M
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
72
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
39
40
41
43
45
48
49
51
53
54
58
59
52
46
33
38
56
226
228
226
231
235
234
238
239
240
242
241
281
283
286
287
290
293
Lake Name
GREEN LAKE
KEGONSA LAKE
KOSHKONONG LAKE
NAGAWICKA LAKE
LAKE POYGAN
SHAWANO LAKE
SINISSIPPI LAKE
TAINTER LAKE
TOWNLINE LAKE
WAPOGASSET LAKE
WISCONSON LAKE
LAKE WISSOTA
TICHIGAN LK-WATERF.
ROCK LAKE
BIG EAU PLEINE RES
GRAND LAKE
WILLOW RESERVOIR
BANKHEAD LAKE
GUNTERSVILLE RESERVOIR
HOLT LOCK AND DAM
MARTIN LAKE
WEISS RESERVOIR
LAKE PURDY
MOORES LAKE
NOXONTOWN POND
SILVER LAKE
WILLIAMS POND
TRUSSUM POND
ALLATOONA RES.
LAKE BLACKSHEAR
CHATUGE LAKE
CLARK HILL RESERVOIR
JACKSON LAKE
SIDNEY LANIER LAKE
County
GREEN LAKE
DANE
JEFFERSON
WAUKESHA
WINNEBAGO, WAUSHARA
SHAWANO
DODGE
DUNN
ONEIDA
POLK
COLUMBIA, SAUK
CHIPPEWA
IMPD RACINE
JEFFERSON
MARATHON
GREEN LAKE
ONEIDA
JEFFERSON, TUSCALOOSA, WALKER
MARSHALL, JACKSON
TUSCALOOSA
COOSA, ELMORE, TALLAPOOSA
CHEROKEE, AL; FLOYD, GA
JEFFERSON, SHELBY
KENT
NEW CASTLE
NE>I CASTLE
SUSSEX
SUSSEX
BARTOW, CHEROKEE, COBB
CRISP, DOOLY, LEE, SUMTER, WORTH
TOWNS, GA; CLAY, NC
COLUMBIA, ELBERT, LINCOLN, MCDUFFIE, WILKS, GA; ABBEVILLE, MCCO
BUTTS, JASPER, NEWTON
DAWSON, FORSYTH, GWINNETT, HALL, LUMPKIN
A13
-------
LAKE NAMES AND CODES
1311
1313
1316
1317
1318
1319
1703
1706
1712
1714
1725
1726
1735
1739
1740
1742
1748
1750
1751
1754
1755
1758
1761
1762
1763
1764
1766
1805
1811
1827
1828
1829
1836
1837
I
I
I
I
I
I
I
I
I
I
N
I
I
I
I
I
I
I
I
I
N
N
I
I
I
I
N
I
I
I
I
I
N
N
M
E
LM
E
LM
E
E
E
E
E
E
E
E
E
E
E
E
E
E
E
E
E
E
E
E
E
E
. E
E
E
E
E
M
E
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
291
294
284
282
285
289
296
297
301
302
309
310
313
315
306
317
320
322
318
307
305
316
321
312
295
319
308
324
327
334
336
337
344
345
Lake Name
NOTTELY RES.
SINCLAIR LAKE
BLUE RIDGE LAKE
LAKE HARDING
BURTON LAKE
HIGH FALLS POND
BLOOMINGTON LAKE
CARLYLE RESERVOIR
CRAB ORCHARD LAKE
LAKE DECATUR
LONG LAKE
LAKE LOU YAEGER
REND LAKE
SHELBYVILLE RESERVOIR
HIGHLAND SILVER LAKE
LAKE SPRINGFIELD
LAKE VERMILION
WONDER LAKE
LAKE STOREY
HOLIDAY LAKE
FOX LAKE
SLOCUM LAKE
LAKE WEE-MA-TUK
RACCOON LAKE
BALDWIN LAKE
LAKE VANDALIA
HORSESHOE LAKE
CATARACT LAKE
GEIST RESERVOIR
MISSISSINEWA RESERVOIR
MONROE RESERVOIR
MORSE RESERVOIR
WAWASEE LAKE
WEBSTER LAKE
County
UNION
BALDWIN, HANCOCK, PUTNAM
FANNIN
HARRIS, GA; CHAMBERS, LEE, AL
RABUN
BUTTS, LAMAR, MONROE
MCLEAN
BOND, CLINTON, FAYETTE
JACKSON, WILLIAMSON
MACON
LAKE
MONTGOMERY
FRANKLIN, JEFFERSON
SHELBY, MOULTRIE
MADISON
SANGAMON
VERMILION
MCHENRY
KNOX
LASALLE
LAKE
LAKE
FULTON
MARION
RANDOLPH
FAYETTE
MADISON
OWEN, PUTNAM
HAMILTON, MARION
GRANT, MIAMI, WABASH
BROWN, MONROE
HAMILTON
KOSCIUSKO
KOSCIUSKO
A14
-------
LAKE NAMES AND CODES
1839
1840
1841
1842
1843
1844
1845
1846
1847
1851
1852
1853
1854
1855
1856
1857
2101
2103
2402
2403
2408
2409
2802
2804
2805
2806
3402
3403
3406
3409
3410
3412
3415
3419
I
N
N
N
N
N
N
N
N
N
I
N
N
N
N
N
I
I
I
I
I
I
I
I
I
I
N
I
I
I
I
I
I
I
E
E
E
E
M
M
E
M
M
E
MU
M
E
E
E
E
M
E
M
M
E
E
E
E
E
E
E
E
E
E
E
E
E
E
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
347
348
346
349
335
342
326
338
339
323
325
331
332
340
333
328
351
353
355
357
358
356
360
362
363
361
364
367
370
372
373
365
368
371
Lake Name
WHITEWATER LAKE
WINONA LAKE
WESTLER LAKE
WITHER LAKE
LAKE MAXINKUCKEE
LAKE TIPPECANOE
DALLAS LAKE
OLIN LAKE
OLIVER LAKE
BASS LAKE
CROOKED LAKE
JAMES LAKE
LONG LAKE
PIGEON LAKE
MARSH LAKE
HAMILTON LAKE
CUMBERLAND LAKE
HERRINGTON LAKE
DEEP CREEK LAKE
LIBERTY RESERVOIR
LOCH RAVEN RESERVOIR
JOHNSON POND
ENID LAKE
ROSS BARNETT RESERVOIR
SARDIS LAKE
GRENADA LAKE
BUDD LAKE
GREENWOOD LAKE
ORADELL RESERVOIR
PINECLIFF LAKE
POMPTON LAKES
DUHERNAL LAKE
LAKE HOPATCONG
PAULINSKILL LAKE
County
UNION
KOSCIUSKO
LAGRANGE
LAGRANGE
MARSHALL
KOSCIUSKO
LAGRANGE
LAGRANGE
LAGRANGE
STARKE
STEUBEN
STEUBEN
STEUBEN
STEUBEN
STEUBEN
STEUBEN
CLINTON, PULASKI, RUSSELL, WAYNE
BOYLE, GARRARD, MERCER
GARRETT
CARROLL, BALTIMORE
BALTIMORE
WICOMICO
YALOBUSHA
JACKSON, MADISON, RANKIN
LAFAYETTE, PANOLA
CALHOUN, GRENADA, YALOBUSHA
MORRIS
PASSAIC, NJ; ORANGE, NY
BERGEN
PASSAIC
PASSAIC
MIDDLESEX
MORRIS, SUSSEX
SUSSEX
A15
-------
LAKE NAMES AND CODES
3420
3423
3641
3701
3702
3704
3705
3706
3707
3711
3713
3715
3716
3717
3718
3719
3901
3902
3905
3906
3907
3908
3912
3914
3921
3924
3927
3928
3929
3930
3931
3932
4201
4204
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
N
I
N
I
I
I
I
I
I
I
I
N
I
I
I
I
I
I
N
E
M
ME
E
E
M
E
E
M
M
E
E
M
E
E
M
E
E
E
E
E
E
E
E
E
E
E
E
E
E
E
E
E
E
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
374
376
147
377
378
379
380
381
382
386
387
388
389
390
392
391
394
396
397
398
399
400
401
403
406
408
411
393
395
402
407
409
415
417
Lake Name
SPRUCE RUN RESERVOIR
WANAQUE RESERVOIR
ALLEGHENY
BADIN LAKE
BLEWETT FALLS LAKE
FONTANA LAKE
HICKORY LAKE
HIGH ROCK LAKE
HIWASSEE LAKE
MOUNTAIN ISLAND LAKE
LAKE NORMAN
RHODHISS LAKE
SANTEETLAH LAKE
LAKE TILLERY
WATERVILLE LAKE
WACCAMAW LAKE
BEACH CITY RESERVOIR
BUCKEYE LAKE
CHARLES MILL RESERVOIR
DEER CREEK RESERVOIR
DELAWARE RESERVOIR
DILLON RESERVOIR
LAKE GRANT
HOOVER RESERVOIR
MOSQUITO CREEK RESERVOIR
PLEASANT HILL RESERVOIR
GRAND LAKE OF ST. MARYS
ATWOOD RESERVOIR
BERLIN RESERVOIR
HOLIDAY LAKE
O'SHAUGHNESSY RESERVOIR
ROCKY FORK RESERVOIR
BLANCHARD RESERVOIR
CONNEAUT LAKE
County
HUNTERDON
PASSAIC
MCKEAN, WARREN, PA; CATTARAUGUS, NY
MONTGOMERY, STANLY
ANSON, RICHMOND
SWAIN, GRAHAM
ALEXANDER, CALDWELL, CATAWBA
DAVIDSON, ROWAN
CHEROKEE
GASTON, MECKLENBURG
CATAWBA, IRADELL, LINCOLN, MECKLENBURG
BURKE, CALDWELL
GRAHAM
MONTGOMERY, STANLY
HAYWOOD
COLUMBUS
STARK, TUSCARAWAS
FAIRFIELD, LICKING, PERRY
ASHLAND, RICHLAND
FAYETTE, PICKAWAY
DELAWARE
MUSKINGUM
BROWN
DELAWARE, FRANKLIN
TRUMBULL
ASHLAND, RICHLAND
AUGLAIZE, MERCER
CARROL, TUSCARAWAS
MAHONING, PORTAGE, STARK
HURON
DELAWARE
HIGHLAND
CENTRE
CRAWFORD
A16
-------
LAKE NAMES AND CODES
4207
4213
4216
4219
4220
4221
4222
4223
4224
4225
4226
4227
4229
4503
4504
4505
4506
4507
4508
4511
4513
4515
4704
4707
4708
4711
4712
4713
4717
4722
4723
4724
4725
4728
I
I
I
I
I
N
N
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
E
E
E
M
M
E
M
M
M
E
E
M
M
E
E
MU
E
ME
MU
E
LM
MU
E
E
E
E
E
M
E
E
E
E
MU
E
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
73
418
425
426
413
414
416
419
420
421
422
423
424
428
430
431
432
434
436
437
441
433
438
443
445
446
447
446
449
446
446
444
455
443
455
Lake Name
GREENLANE RESERVOIR
PYMATUNING RESERVOIR
SHENANGO RIVER RESERVOIR
BEAVER RUN RESERVOIR
BELTZVILLE LAKE
LAKE CANADOHTA
HARVEYS LAKE
INDIAN LAKE
LAKE NAOMI
LAKE ONTELAUNEE
CONEWAGO LAKE (PINCHOT)
POCONO LAKE
LAKE WALLENPAUPACK
FISHING CREEK RES
LAKE GREENWOOD
LAKE HARTWELL
LAKE MARION
LAKE MURRAY
LAKE ROBINSON
LAKE WYLIE
LAKE KEOWEE
SALUDA LAKE
BOONE RESERVOIR
CHEROKEE LAKE
CHICKAMAUGA RESERVOIR
DOUGLAS LAKE
FT. LOUDOUN RESERVOIR
GREAT FALLS LAKE
NICKAJACK RESERVOIR
WATTS BAR RESERVOIR
J. PERCY PRIEST RES.
TIMS FORD RESERVOIR
SOUTH HOLSTON RESERVOIR
WOODS RESERVOIR
County
MONTGOMERY
CRAWFORD, PA; ASHTABULA, OH
MERCER
WESTMORELAND
CARBON
CRAWFORD
LUZERNE
SOMERSET
MONROE
BERKS
YORK
MONROE
PIKE, WAYNE
CHESTER, LANCASTER
GREENWOOD, LAURENS, NEWBERRY
ANDERSON, OCONEE, PICKENS, SC; FRANKLIN, HART, STEPHENS, GA
BERKELEY, CALHOUN, CLARENDON, ORANGEBURG, SUMTER
FAIRFIELD, LEXINGTON, NEWBERRY, SALUDA, RICHLAND
CHESTERFIELD, DARLINGTON
YORK, SC; GASTON, MECKLENBURG, NC
OCONEE, PICKENS
GREENVILLE, PICKENS
WASHINGTON, SULLIVAN, CARTER
JEFFERSON, HAMBLEN, GRAINGER, HAWKINS
HAMILTON, RHEA, MEIGS, MCMINN
SEVIER, JEFFERSON, COCKE
LOUDON, KNOX, BLOUNT
WHITE, VAN BUREN
MARION, HAMILTON
CUMBERLAND, LOUDON, MEIGS, RHEA, ROANE
DAVIDSON, RUTHERFORD
FRANKLIN, MOORE
SULLIVAN, TN; WASHINGTON, VA
FRANKLIN, COFFEE
A17
-------
LAKE NAMES AND CODES
5103
5105
5106
5108
5110
5111
5112
5113
5401
5402
5403
5404
0501
0502
0504
0505
0506
0507
0508
0510
0514
0515
0516
1901
1902
1903
1907
1908
1909
1910
1911
1912
1914
2001
I
I
I
I
I
I
I
I
I
I
I
I
I
N
I
I
I
I
I
I
I
I
I
I
I
N
N
I
I
I
I
N
I
I
E
M
E
E
ME
E
E
E
E
M
M
M
M
HE
M
E
E
M
E
E
M
M
M
E
E
E
E
E
E
E
E
E
E
M
73
73
73
73
73
73
73
73
73
73
73
73
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
460
463
462
464
465
458
459
466
467
468
469
470
480
481
480
483
484
485
486
483
483
480
487
494
495
496
500
501
502
503
504
505
507
511
Lake Name
CLAYTOR LAKE
JOHN W FLANNAGAN RES.
JOHN H KERR RES
OCCOQUAN RESERVOIR
SMITH MOUNTAIN RESERVOIR
LAKE CHESDIN
CHICKAHOMINY LAKE
RIVANNA RESERVOIR
BLUESTONE RESERVOIR
LAKE LYNN
SUMMERSVILLE RESERVOIR
TYGART RESERVOIR
BEAVER RESERVOIR
BLACKFISH LAKE
BULL SHOALS RESERVOIR
LAKE CATHERINE
CHICOT LAKE
DEGRAY RESERVOIR
LAKE ERLING
HAMILTON LAKE
OUACHITA LAKE
TABLE ROCK RESERVOIR
GREER'S FERRY RESERVOIR
LAKE AHQUABI
BIG CREEK RESERVOIR
BLACK HAWK LAKE
LAKE MACBRIDE
PRAIRIE ROSE LAKE
RATHBUN RESERVOIR
RED ROCK RESERVOIR
ROCK CREEK LAKE
SILVER LAKE
VIKING LAKE
CEDAR BLUFF RESERVOIR
County
PULASKI
DICKENSON
HALIFAX, MECKLENBURG, VA; GRANA/ILLE, VANCE, WARREN, NC
FAIRFAX
BEDFORD, FRANKLIN, PITTSYLVANIA
AMELIA, CHESTERFIELD, DINWIDDIE
NEW KENT, CHARLES
ALBERMARLE
GILES, VA; MERCER, MONROE, SUMMERS, WV
MONONGALIA
NICHOLAS
BARBOUR, TAYLOR
BENTON, CARROLL, WASHINGTON
CRITTENDEN, ST. FRANCIS
BAXTER, BOONE, MARION, AR; TANEY, OZARK, MO *
GARLAND, HOT SPRING
CHICOT
CLARK, HOT SPRING
LAFAYETTE
GARLAND
GARLAND, MONTGOMERY
BOONE, CARROLL, AR; BARRY, TANEY, MO
VAN BUREN, CLEBURNE
WARREN
POLK
SAC
JOHNSON
SHELBY
APPANOOSE, LUCAS, MONROE, WAYNE
MARION
JASPER
WORTH
MONTGOMERY
TREGO
A18
-------
LAKE NAMES AND CODES
2002
2003
2005
2006
2007
2008
2009
2010
2011
2012
2014
2015
2203
2204
2205
2210
2211
2215
2217
2220
2902
2903
2905
3101
3102
3103
3104
3105
3106
3107
3110
3801
3804
3807
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
N
I
I
I
I
I
I
I
I
I
I
I
I
I
I
E
E
E
E
E
E
E
E
E
E
E
M
E
E
E
E
MU
E
M
E
E
E
E
E
HE
E
E
E
MU
E
E
E
E
E
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
512
513
515
516
517
518
519
520
521
522
524
525
529
530
533
538
539
543
528
535
548
549
550
553
555
556
557
558
559
560
562
565
568
571
Lake Name
COUNCIL GROVE RESERVOIR
ELK CITY RESERVOIR
JOHN REDMOND RESERVOIR
KANOPOLIS RESERVOIR
MARION RESERVOIR
MELVERN RESERVOIR
MIL'FORD RESERVOIR
NORTON RESERVOIR
PERRY RESERVOIR
POMONA RESERVOIR
TUTTLE CREEK RESERVOIR
WILSON RESERVOIR
LAKE BISTINEAU
BLACK BAYOU RESERVOIR
BUNDICK LAKE
CROSS LAKE
BAYOU D'ARBONNE LAKE
TURKEY CREEK LAKE
LAKE VERNON
COCODRIE LAKE
POMME DE TERRE RESERVOIR
STOCKTON RESERVOIR
THOMAS HILL RESERVOIR
BRANCHED OAK RESERVOIR
HARLAN COUNTY RESERVOIR
HARRY D. STRUNK RES.
HUGH BUTLER RESERVOIR
JOHNSON RESERVOIR
C.W. MCCONAUGHY RES.
PAWNEE RESERVOIR
SWANSON RESERVOIR
LAKE ASHTABULA
LAKE DARLING
LAKE LAMOURE
County
MORRIS
MONTGOMERY
COFFEY, LYON
ELLSWORTH
MARION
OSAGE
CLAY, GEARY
NORTON
JEFFERSON
OSAGE
MARSHALL, POTTAWATOMIE, RILEY
RUSSELL
BIENVILLE, BOSSIER, WEBSTER
CADDO
BEAUREGARD
CADDO
UNION, LINCOLN
FRANKLIN
VERNON
RAPIDES
POLK, HICKORY
DADE, POLK, CEDAR
MACON, RANDOLPH
LANCASTER
HARLAN
FRONTIER
FRONTIER, RED WILLOW
DAWSON, GOSPER
KEITH
LANCASTER
HITCHCOCK
BARNES, GRIGGS
RENVILLE, WARD
LAMOURE
A19
-------
LAKE NAMES AND CODES
3808
3812
3814
4001
4002
4003
4004
4005
4006
4008
4009
4010
4011
4012
4013
4014
4602
4603
4610
4620
4624
4626
4627
4629
4801
4802
4803
4805
4806
4808
4809
4810
4811
4812
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
E
OU
E
E
M
E
E
E
E
E
E
E
E
E
E
E
E
M
M
0
E
E
E
E
M
MU
MU
E
E
E
M
E
E
E
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
572
575
577
581
582
583
584
585
586
588
589
590
591
592
593
594
599
600
607
617
621
623
624
626
631
632
633
635
636
638
639
640
641
642
Lake Name
MATEJCEK LAKE
LAKE SAKAKAWEA
SWEET BRIAR LAKE
ALTUS RESERVOIR
ARBUCKLE LAKE
LAKE ELSWORTH
LAKE EUFAULA
FORT COBB RESERVOIR
FORT SUPPLY RESERVOIR
LAKE FRANCES
GRND LK O1 THE CHEROKEES
LAKE HEFNER
KEYSTONE RESERVOIR
OOLOGAH RESERVOIR
TENKILLER FERRY RES.
LAKE THUNDERBIRD
LAKE ALVIN
ANGOSTURA RESERVOIR
DEERFIELD LAKE
PACTOLA RESERVOIR
RICHMOND LAKE
SAND LAKE
SHERIDAN LAKE
EAST VERMILLION LAKE
AMISTAD RESERVOIR
LAKE BASTROP
BELTON RESERVOIR
LAKE BROWNWOOD
LAKE BUCHANAN
CALAVERAS LAKE
CANYON RESERVOIR
LAKE COLORADO CITY
LAKE CORPUS CHRISTI
LAKE DIVERSION
County
WALSH
DUNN, MCKENZIE, MCLEAN, MERCER, MOUNTRAIL, WILLIAMS
MORTON
GREER, KIOWA
MURRAY
CADDO, COMANCHE
HASKELL, MCINTOSH, OKMULGEE, PITTSBURG
CADDO
WOODWARD
ADAIR
MAYES, DELAWARE, CRAIG, OTTOWA
OKLAHOMA
TULSA, OSAGE, CREEK, PAWNEE
NOWATA, ROGERS
CHEROKEE, SEQUOYAH
CLEVELAND
LINCOLN
FALL RIVER
PENNINGTON
PENNINGTON
BROWN
BROWN
PENNINGTON
MCCOOK
VAL VERDE
BASTROP
BELL, CORYELL
BROWN
BURNET, LLANO
BEXAR
COMAL
MITCHELL
JIM WELLS, LIVE OAK, SAN PATRICIO
ARCHER, BAYLOR
A20
-------
LAKE NAMES AND CODES
4813
4814
4815
4816
4817
4818
4819
4820
4821
4822
4823
4824
4825
4826
4827
4828
4829
4830
4831
4832
4834
4835
4837
4838
4839
0403
0404
0405
0406
0409
0410
0411
0601
0602
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
N
I
I
I
I
MU
E
E
E
E
E
E
E
E
MU
M
E
MU
E
E
E
E
E
M
E
E
M
E
MU
E
M
E
E
M
E
M
E
E
0
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
75
75
75
75
75
75
75
75
75
643
644
650
646
647
648
649
651
645
652
653
654
655
656
657
658
659
660
661
662
663
664
666
667
668
728
729
730
731
734
735
736
739
740
Lake Name
EAGLE MOUNTAIN LAKE
LAKE FORT PHANTOM HILL
LAKE LEWISVILLE
LAKE KEMP
LAKE HOUSTON
LAKE. 0' THE PINES
LAKE LAVON
LIVINGSTON RESERVOIR
LAKE LYNDON B. JOHNSON
MEDINA LAKE
LAKE MEREDITH
PALESTINE RESERVOIR
POSSUM KINGDOM RESERVOIR
0. C. FISHER
SAM RAYBURN RESERVOIR
E. V. SPENCE RESERVOIR
SUMMERVILLE LAKE
LAKE STAMFORD
STILLHOUSE HOLLOW RESERV.
LAKE TAWAKONI
LAKE TEXOMA
LAKE TRAVIS
TWIN BUTTES RESERVOIR
WHITE RIVER RESERVOIR
WHITNEY RESERVOIR
LAKE HAVASU
LUNA LAKE
LYMAN LAKE
LAKE MOHAVE
RAINBOW LAKE
THEODORE ROOSEVELT LAKE
SAN CARLOS RESERVOIR
LAKE AMADOR
BOCA RESERVOIR
County
TARRANT, WISE
JONES
DENTON
BAYLOR
HARRIS
CAMP, MARION, MORRIS, UPSHUR
COLLIN
POLK, SAN JACINTO, TRINITY, WALKER
BURNET, LLANO
BANDERA, MEDINA
HUTCHINSON, MOORE, POTTER
ANDERSON, CHEROKEE, HENDERSON, SMITH
PALO PINTO, STEPHENS, YOUNG
TOM GREEN
ANGELINA, JASPER, NACOGDOCHES, SABINE, SAN AUGUSTINE
COKE
BURLESON, LEE, WASHINGTON
HASKELL
BELL
HUNT, RAINS, VAN ZANDT
COOKE, GRAYSON, TX; BRYAN, JOHNSON, LOVE, MARSHALL, OK
BURNET, TRAVIS
TOM GREEN
CROSBY
BOSQUE, HILL
MOHAVE, AZ; SAN BERNARDINO, CA
APACHE
APACHE
MOHAVE, AZ; CLARK, NV
NAVAJO
GILA
GILA, GRAHAM, PINAL
AMADOR
NEVADA
A21
-------
LAKE NAMES AND CODES
0606
0608
0611
0614
0616
0620
0621
0624
0625
0626
0801
0803
0804
0806
0807
0808
0812
1601
1602
1603
1604
1608
1609
1611
1612
1613
3001
3002
3003
3005
3007
3008
3009
3010
I
N
I
I
I
I
I
I
N
N
I
I
I
I
N
I
I
I
I
N
I
I
I
N
I
I
I
I
N
I
N
N
I
N
M
0
E
E
MU
E
M
E
M
M
M
M
E
0
M
0
MU
E
E
M
0
E
E
M
E
E
E
E
0
MU
MU
0
E
MU
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
744
746
749
750
752
756
757
760
762
761
765
767
768
769
770
771
775
776
777
778
779
783
785
784
787
787
790
791
792
794
796
797
798
799
Lake Name
DON PEDRO RESERVOIR
FALLEN LEAF LAKE
IRON GATE RESERVOIR
LOPEZ RESERVOIR
LAKE MENDOCINO
SANTA MARGARITA LAKE
SHASTA LAKE
TULLOCK RESERVOIR
UPPER TWIN LAKE
LOWER TWIN LAKE
BARKER RESERVOIR
BLUE MESA RESERVOIR
CHERRY CREEK LAKE
DILLON RESERVOIR
GRAND LAKE
GREEN MOUNTAIN RESERVOIR
NAVAJO RESERVOIR
AMERICAN FALLS RESERVOIR
CASCADE RESERVOIR
COEUR D'ALENE LAKE
DWORSHAK RESERVOIR
LAKE LOWELL
MAGIC RESERVOIR
PAYETTE LAKE
LOWER TWIN LAKES
UPPER TWIN LAKES
CANYON FERRY RESERVOIR
CLARK CANYON RESERVOIR
FLATHEAD LAKE
HEBGEN LAKE
MARY RONAN LAKE
LAKE MCDONALD
NELSON RESERVOIR
SEELEY LAKE
County
TUOLUMNE
EL DORADO
SISKIYOU
SAN LUIS OBISPO
MENDOCINO
SAN LUIS OBISPO
SHASTA
CALAVERAS, TUOLUMNE
MONO
MONO
BOULDER
GUNNISON
ARAPAHOE
SUMMIT
GRAND *** INCLUDES TRIBS AND LOADS FOR SHADOW MTN LAKE (0813)
SUMMIT
ARCHULETA, CO; SAN JUAN, RIO ARRIBA, NM
BANNOCK, BINGHAM, POWER
VALLEY
BENEWAH, KOOTENAI
CLEARWATER
CANYON
CAMAS, BLAINE
VALLEY
KOOTENAI
KOOTENAI
BROADWATER, LEWIS & CLARK
BEAVERHEAD
FLATHEAD, LAKE
GALLATIN
LAKE
FLATHEAD
PHILLIPS
MISSOULA
A22
-------
LAKE NAMES AND CODES
son
3012
3013
3014
3016
3201
3202
3204
3206
3501
3502
3503
3505
3506
3507
3509
4101
4104
4106
4107
4901
4903
4904
4906
4908
4909
4910
4913
4914
4915
4917
4920
4921
4923
N
N
I
I
N
I
I
I
N
I
I
I
I
I
I
I
I
I
N
N
I
I
N
I
I
N
I
N
N
I
I
I
I
M
OM
MU
E
0
LM
E
E
E
E
MU
M
E
MU
. E
M
E
E
E
MU
0
E
E
ME
M
E
0
E
. E
E
E
E
M
M
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
800
801
802
803
804
808
807
809
811
817
818
819
821
822
823
824
827
830
832
833
836
837
838
839
.841
846
847
850
851
852
854
857
858
860
Lake Name
SWAN LAKE
TALLY LAKE
TIBER RESERVOIR
TONGUE RIVER RESERVOIR
WHITEFISH LAKE
LAKE MEAD
LAHONTAN RESERVOIR
RYE PATCH RESERVOIR
TOPAZ LAKE
ALAMOGORDO RESERVOIR
BLUEWATER LAKE
CONCHAS RESERVOIR
ELEPHANT BUTTE RESERVOIR
EL VADO RESERVOIR
LAKE MCMILLAN
UTE RESERVOIR
BROWNLEE RESERVOIR
HILLS CREEK RESERVOIR
OXBOW RESERVOIR
SUTTLE LAKE
BEAR LAKE
DEER CREEK RESERVOIR
ECHO RESERVOIR
FISH LAKE
JOES VALLEY RESERVOIR
MINERSVILLE RESERVOIR
MOON LAKE
OTTER CREEK RESERVOIR
PANGUITCH LAKE
PELICAN LAKE
PIUTE RESERVOIR
SEVIER BRIDGE RESERVOIR
STARVATION RESERVOIR
TROPIC RESERVOIR
County
LAKE
FLATHEAD
LIBERTY, TOOLE
BIG HORN
FLATHEAD
CLARK, NV; MOHAVE, AZ
CHURCHILL, LYON
PERSHING
DOUGLAS, NV; MONO, CA
DE BACA, GUADALUPE
MCKINLEY, VALENCIA
SAN MIGUEL
SIERRA, SOCORRO
RIO ARRIBA
EDDY
QUAY
BAKER, OR; WASHINGTON, ID
LANE
BAKER, OR; ADAMS, ID
JEFFERSON
RICH, UT; BEAR LAKE, ID
WASATCH
SUMMIT
SEVIER
EMERY
BEAVER
DUCHESNE
PIUTE
GARFIELD
UINTAH
PIUTE
JUAB, SANPETE
DUCHESNE
GARFIELD
A23
-------
LAKE NAMES AND CODES
4924 N HE
4925 I E
5306 I 0
5309 I E
5311 N MU
5312 N M
5601 I E
5602 N 0
5603 I E
5605 I ME
5606 N 0
5607 I E
5608 I E
5609 N E
5610 I ME
5613 I E
5614 I ME
Lake Name
75 861 UTAH LAKE
75 862 WILLARD RESERVOIR
75 869 KEECHELUS LAKE
75 872 MOSES LAKE
75 874 SAMMAMISH LAKE
75 875 LAKE WHATCOM
75 881 BIG SANDY RESERVOIR
75 882 BOULDER LAKE
75 883 BOYSEN RESERVOIR
75 885 FLAMING GORGE RESERVOIR
75 886 FREMONT LAKE
75 887 GLENDO RESERVOIR
75 888 KEYHOLE RESERVOIR
75 889 OCEAN LAKE
75 890 SEMINOE RESERVOIR
75 893 WOODRUFF NARROWS RES.
75 894 YELLOWTAIL RESERVOIR
County
UTAH
BOX ELDER
KITTITAS
GRANT
KING
-WHATCOM
SUBLETTE, SWEETWATER
SUBLETTE
FREMONT
SWEETWATER, WY; DAGGETT, UT
SUBLETTE
CONVERSE, PLATTE
CROOK
FREMONT
CARBON
UINTA
BIGHORN, WY; BIGHORN, CARBON, MT
A24
-------
LOCATIONS OF LAKES IN 1972-1975 SURVEYS
A25
-------
LAKE DATA 1972-1975
A26
-------
LAKE DATA
TETRA TECH.,INC.
3700 MT. DIABLO BLVD.
LAF., CA. 94549
YEAR : 1972 TO 1975
TOTAL NUMBER OF LAKES
493
: STORET
: NUMBER
:
•
•
: 0101
: 0104
0105
: 0107
: 0112
: 01 15
0403
: 0404
: 0405
: 0406
: 040S
: 0410
: 041 1
: 0501
: 0502
: 0504
0505
: 0506
: 0507
: 0508
: 0510
0514
: 0515
0516
: 0601
: 0602
: 0606
: 0608
: 0611
: 0614
: 0616
: 0620
: 0621
I 0624
SURFACE
AREA
2
(KM )
37.23
274.99
13.36
157.83
122.22
4.30
77.30
.30
5.67
105.63
.32
60.70
52.61
114.20
1.62
183.89
7.85
21 .45
54.23
28.33
24.28
162.28
174.42
163.90
1.56
3.97
52.45
5.71
3.39
3.80
7.92
3. IB
119.40
: 5.10
DRAINAGE
AREA
2
(KM )
10334.10
63325.50
10960.90
7674.20
13649.40
106.40
463091 .80
93.50
2046.10
438486.80
26.20
15084.20
33374.70
3087.30
288.80
15672.10
3926.40
1046.40
1173.30
1023.00
3732.20
2861 .90
1041 1 .80
2986.30
151 .30
445.50
3957.90
43.30
11838.90
175.30
271 .90
290.10
16630.40
I 2533.30
MEAN
DEPTH
(M)
3. 10
4-60
7.90
12.90
2.80
5.10
9.20
2.50
6.70
18.90
4.60
28.00
15.30
17.80
1 .80
20.40
5.50
2.70
14.90
2.10
9.70
16.30
19. 10
21.40
17.40
12.80
47.70
1 .50
21 .40
16.60
19.10
10.10
46.50
: 16.50
VOLUME
6 3
(10 M )
115.413
1264.954
105.544
2036.007
342.216
21 .930
71 1 . 160
.750
37.989
1996.407
1 .472
1699.600
804.933
2032.760
2.916
3751 .356
43.175
57.915
808.027
59.493
235.516
2645.164
3331 .422
3507.460
27. 144
50.816
2501 .865
8.565
72.546
63.080
151.272
t 32.118
! 5552.100
I 64.150
RETENTION
TIME
(YEARS)
.020
.035
.017
.482
.043
.298
.087
.297
2.362
. 199
.467
1 .896
2.941
1 .522
.022
.708
.021
. 133
1 .309
.179
. 1 19
1 .857
.903
2.246
.715
.308
1 .693
. 180
.031
7.300
.461
1.577
.596
.052
MEDIAN
PHOSPHORUS
(MG/L)
.029
.044
.018
.017
.092
.049
.015
.182
.099
.017
.046
.020
.056
.022
.424
.015
.029
.162
.019
.054
.024 .
.015
.022
.012
.040
.012
.013
.007
.184
.371
.020
.037
.021
: .025
SECCHI
DISK
(M)
1.2
1 .0
1 .3
1.7
.6
1.6
2.0
2.6
.4
3.3
1.5
1.8
.7
2.1
.1
3.4
1.2
. .4
2. 1
1.2
i .a
2.8
2.3
3.3
2.3
3.2
3.0
12.1
1.5
3.3
1.6
2.5
3.0
1.7
MEAN
CHL-A
(UG/L)
4.0
8.6
2.2
6.4
11.3
12.7
3.9
3.4
2.6
4.4
16.4
4.1
14.8
3.9
19.8
3.9
14.0
13.7
12.3
13.4
10.9
4.3
9. 1
3.8
'*""" 22.4
1 .7
3.6
.8
6.2
B.7
3.1
9.1
4.1
13.9
RESPONSE
TIME
(YEARS)
.0047
.0222
.0080
. 1264
.0181
.0828
.0403
. 1943
.5769
.1106
. 1575
.2316
.0426
.2384
.0123
.3073
.0090
.0745
.7892
.0822
.0391
1 .0701
. 1601
.8074
.2336
.1682
.5654
.0997
.0197
3.3891
.1957
.6562
.3574
.0310
A27
-------
YEAR : 1972 TO 1975
TOTAL NUMBER OF LAKES
493
LAKE DATA
TETRA TECH..INC.
3700 MT. DIABLO BLVD.
LAP., CA. 94549
STORET !
NUMBER
0625
0626
0801
0803
0804
0806
0807
0808
0812
0901
0904
0905
0910
0911
0912
1005
1007
1008
100S
1010
1301
1302
1303
1304
1309
1310
1311
1313
1316
1317
1318
1319
: 1601
: 1602
SURFACE
AREA
2
(KM )
1.07
1.52
1 .70
36.62
3.24
12.76
2.05
8.60
63.25
1.35
.32
.26
3.95
7.69
1 .33
.10
.64
. 15
.34
.22
48.00
34.46
28.94
283.29
19.22
161 .47
17.36
62.17
13.44
23.67
11.23
2.43
277.03
107.24
DRAINAGE
AREA
2
(KM )
76.40
101 .30
99.20
8873.30
997.10
867.60
479. 10
1551 .40
8443.40
1851 .80
287.50
246.30
3991 .10
3605.20
4076.60
35.20
24.40
19.50
59.80
38.60
2845.00
9712.50
489.50
15893.20
3627. 10
2663.30
557.00
7510.90
600.80
10982.00
297.90
533.30
35224.00
1621.30
MEAN
DEPTH
(M)
14.30
15.20
8.30
31.10
5.20
24.60
41.30
22.20
33.30
2.65
.91
1.37
7.50
11 .86
2.87
1.10
1.10
1.50
1 .20
1 .20
9.40
5.30
10.60
10.90
6.90
19.50
13.10
6.60
18.40
9.40
11.90
3.70
9.20
8.10
VOLUME
6 3
(10 M )
15.301
23. 104
14.110
1138.882
16.848
313.896
84.665
190.920
2106.225
3.574
.296
.355
29.585
91 .166
3.803
. 1 10
.704
.225
.408
.264
451 .200
182.638
306.764
3087.861
132.618
3148.665
227.416
410.322
247.296
222.498
133.637
B.991
2548.676
: 668.644
RETENTION
TIME
(YEARS)
.372
.431
.283
.758
3.634
1 .305
.202
.450
1 .350
.003
.002
.002
.013
.046
.002
.004
.053
.022
.008
.016
.283
.043
.81 1
.370
.085
1 .650
.633
.146
.481
.038
.441
.038
.364
.929
MEDIAN
PHOSPHORUS
(MG/L)
.015
.014
.023
.019
.054
.009
.013
.010
.036
.092
.094
.298
.043
.054
.039
.245
. 160
.227 .
.042
.038
.020
.035
.014
.024
.094
.016
.015
.028
.010
.114
.007
.047
.105
.032
SECCHI
DISK
(M)
5.1
6.4
2.1
2.7
.8
8.1
3.4
2.8
.5
.8
1.6
1.0
1.9
3.7
1.9
.7
.6
.9
1.3
.9
1.5
.8
3.0
1 .5
1.0
2.6
2.4
1.5
2.7
.8
3.5
1.0
.9
2.2
MEAN
CHL-A
(UG/L)
3.3
2.9
5.3
6.8
23.3
3.2
4.9
5.8
2.2
35.8
7.1
18.9
18.3
11.1
10.2
81 .3
37.6
26.7
30.1
5. 1
7.5
1 .9
6.3
6.7
14.6
5.4
6.7
8.0
3.1
7.4
2.7
15.1
15.4
8.1
RESPONSE
TIME
(YEARS)
. 1769
.2474
.1673
. 1647
.3711
.2574
.0801
.3010
. 1649
.0021
.0010
.0016
.0069
.0158
.0010
.0024
.0202
.0077
.0057
.0071
.0691
.0176
.3954
.0971
.0216
. 1207
.2676
.0690
.2124
.0122
.1371
.0200
.2373
.4110
A28
-------
LAKE DATA
TETRA TECH.,INC.
3700 MT. DIABLO BLVD.
LAF.. CA. 94549
YEAR : ,1,9,72 TO- 19,75
TOTAL NUMBER OF LAKES
493
STORET
NUMBER
1603 :
1604
1608
1609
1611
1612
1613
V703
•1706
1712
1714
1725
1726
1735
173S
1740
1742
748
750
751
754
755
758
1761
1762
1763
1764
1766
1805
1811
' 1827
: '1828
: 1823
1 1B36
SURF.ACE
AREA
• 2
(KM )
129.50
76.89
39.80
15.80
21 .60
16.35
16.35
1 .97
105.22 •
28.19
1 1.35
1.03 .
5.72
76-.49 •
44:52
2:99
17.13
2.83
2V95
.53
1 .21
6.76
.87
2.38
3.93
8.00
2.67
8.78
5.66
7.2B
lfc.75
43.50
5.57
12.38
DRAINAGE .
AREA
2 !
(KM )
9945.60 '
6319.60
• - r
41 44 .00
373.00
1 33 .40
133.40
180.00
7042.20
520.60
2429.40
,,%9vlO „
279.70
•1300.20
2729.90 ;
122.00
681 .20
774.40 -
252.00
18.20
; 1 68-. 1 0
3120.90
22.60
49:50
125.90
12.60
62.90
83.10
762.00
559.20
2091. .20
11 19.70 ,
555 .30
94.20
MEAN :
D'EPTH
(M)
2.30
55.50
5 .90
15.00
5 . 70
2.30
2 .30
5.00
2.70
3.00
1 .40
1 ..60
"3 ."30
4.70
5.00
4.20
4-00
1.40
2.50
4.60
2.70
2.40
1 .20
1 .80
1 .20
3.10
16.20
2. 10
6': 1 0
3.60
7.20
5 .30
4i70
6.70
VOLUME '_
6 3
(10 M )
297.850
4267.395
234.820
237 .'000
123.120
37.605
37 .605
9 . 850 '
284.094
84.570
15:890
1 .648
18.876
359.5'03
222.600
1 2 . 558
68.520
3.962
7.375
2.438
3.267
16.224
1 .044
4.284
4.716
24.800
43.254
1 8 . 438
34.526
26.208
91 .800
2301550 -
26.179
82.946
RETENTION
TIME
(YEARS)
.654
.837
.720
.480
.383
1.807
1.807
.390
.176
.789
.029
.087
:333
1 .239
;360
.517
..483
.025
. 146
.773
.104
.023
.331
.453
. 187
7.864
3.429
1 . 169
.137
.159
.139
.667
.154
. 3.4J61
MEDIAN
PHOSPHORU'S
(MG/L)
.017
.010
.070
.062
.013
.016
.017
.050
.084
.082
.129
.704
.186
.071
. 06*2
.226
.108
.109
.426
.072
.167
.219
.865
.069
.106
.044
.116
.127
.058
.074
.107
.025
.084
.012
SECCHl
'DISK
(M)
3.0
2.5
g
2.5
6.8
3.3
3.3
.9
.6
.4
.5
.4
.3
.7
1 .0
.3
.4
.5
.4
1.0
.4
.4
.3
.9
.4
1.0
.6
.4
.8
.7
.7
r.s
".7
3.5
•MEAN
CHL-A
(UG/.L.)
10.4
2.4
25.4
7.3
4.6
2.3
5.0
26.2
17.4
59.9
43.0
49.3
10.7
23.5
17.2
5.8
13.0
31.1
98.5
17.2
51.2
63.8
221 . 1
8.0
19.2
11.3
11.3
182.2
10'. 7 :
46.0
15.8
6:9
'56:2
5.0
RESPONSE
T,I;ME
(YEARS)
.0225 .
.4209
.2817
. 1368
.260.1
. 1 533
. 1533
. 1851
.0743
.1110
.0148
.0227
. 2040
.4309
.0857
.2773
.2482
.0114
.0441
. 1638
.0467
.0147
.0918
«» .1453
.0921
. 1031
2.0797
.6729
.0538
.0662
-.0482
.2568
i'0505
.9576
A29
-------
YEAR : 1972 TO 1975
TOTAL NUMBER OF LAKES
493
LAKE DATA
TETRA TECH..INC.
3700 MT. DIABLO BLVD.
LAP., CA. 94549
: STORET
NUMBER
1B37
1839
1840
1841
1842
1843
1844
1845
1846
1847
1851
1852
1853
1854
1855
1856
1857
1901
1902
1903
1907
1908
1909
1910
191 1
1912
1914
2001
2002
: 2003
: 2005
: 2006
: 2007
i 2008
SURFACE
AREA
2
(KM )
2.37
.81
2.27
• 36
.83
7.54
3.11
1.14
.42
1 .50
5.69
3.25
4. IB
.37
.25
• 23
3.25
.53
3.44
3.72
3.84
.88
44.52
36.22
2.60
1.29
.61
26.84
13.27
17.81
38.04
14.37
24.93
28.05
DRAINAGE
AREA
o
(KM )
126.70
49.80
83. 10
97.90
93.50
35.50
292.70
103.10
15.00
28.70
13.40
30.80
123.80
176.10
82.90
38.60
42.80
12.80
203.60
60.30
69.90
20.40
1421 .90
31916.60
107.20
8.20
10.30
14322.70
647.50
1642.10
7808.80
20349.60
518.00
909.10
MEAN
DEPTH
(M)
2. 10
4.60
9.10
6.10
10.40
7.30
11 .30
10.80
11 .70
12.20
1 .80
6.10
7.30
5. 10
4.60
6. 10
6-30
3.00
6.70
1 .70
7.30
3.30
6.70
3.00
2.70
1 .20
5-80
8.50
3.90
2.40
2.00
4.50
4.10
6.00
VOLUME
6 3
(10 M )
4.977
3.726
20.657
2. 196
8.632
55.042
35. 143
12.312
4.914
18.300
10.242
19.825 .
30.514
1 .887
1 .150
1 .403
20.475
1.590
23.048
6.324
28.032
2.904
298.284
108.660
7.020
1 .548
3.538
228. 140
51 .753
42.744
76.080
64.665
102.213
I 168.300
RETENTION
TIME
(YEARS)
.132
.257
.819
.077
.304
5.818
.407
.390
1.113
2.321
3.248
2.619
.856
.035
.048
. 124
1 .803
.720
.738
.743
2. 168
1 . 151
1 .046
.028
.391
1 .227
1 .603
4.255
.597
. 125
.062
.212
2.437
1.061
MEDIAN
PHOSPHORUS
(MG/L)
.025
.084
.035
.035
.035
.020
.019
.029
.012
.009
.040
.019
.016
.204
.058
.093
' .033
.062
.046
. 185
.061
.056
.071
. 180
.065
.193
.075
.017
.069
.030
.118
.056
.052
.034
SECCHI
DISK
(M)
1.7
.7
1 .4
1.9
1.5
2.6
2.8
2.2
2.4
2.8
.7
2.3
3.7
1.5
1 .5
1.2
2.2
.8
1.6
.3
1 .1
.9
.6
.7
.5
.4
1.0
1.7
.4
.2
.2
.3
.4
1.0
MEAN
CHL-A
(UG/L)
11 .5
33. 1
11.2
10.7
11.9
5.5
6.0
10. 1
4.9
3.8
29.4
5.6
4.9
16.1
1 1 .9
34.5
17.4
8.6
16.9
49.7
17.1
17.4
12.0
14.7
18.4
95.3
26.0
4.2
9.8
3.2
9.5
16.0
12.4
30.4
RESPONSE
TIME
(YEARS)
.0458
.0642
.2960
o -0473
.1414
.6784
. 1981
.2'524
. 1582
.7335
1.1317
.3868
.2452
.0162
.0264
.0798
.6521
,1655
. 1340
.4115
.4189
.2129
. 1278
.0077
.0480
.5377
.6270
1 .3830
. 1351
.0476
.0245
.0322
.4691
.2804
A30
-------
LAKE DATA
TETRA TECH.,INC.
3700 MT. DIABLO BLVD.
LAP., CA. 94549
YEAR : 1972 TO 1975
TOTAL NUMBER OF LAKES
493
STORET
NUMBER
2003
2010
2011
2012
2014
2015
2101
2103
2203
2204
2205
2210
221 1
2215
2217
2220
2304
2306
2308
2309
2310
231 1
2312
2313
2314
2402
2403
240B
2409
2502
2503
2507
2508
1 2513
SURFACE
AREA
2
(KM )
65.51
8. 86
49.37
16.19
63.94
36.42
203.36
1 1 .90
69.67
16.06
7.07
35.77
61.64
12.54
17.09
24.68
1.57
19.70
13.48
303.07
24.28
116.43
17.35
24.28
3.08
15.78
12.59
7.67
.42
.10
.36
.49
.15
.12
DRAINAGE
AREA
2
(KM )
64465. 10
1771 .60
2893.00
834.00
24967.60
4965.00
14993.50
1137.00
3752.90
608.60
546.50
655.30
4162. 10
461 .00
295.30
621 .40
271 .90
295.30
813.20
3279.90
256.40
1142.20
326.30
234.10
308.20
167.60
424.80
791 .60
96.10
4.40
85.70
445.50
356.90
168.30
MEAN
DEPTH
(M)
7.80
5.00
3.70
6.40
8.20
8-40
24.20
23.90
2.10
1 .40
1 .60
2.70
2.60
2.00
4. 10
.50
3.05
10.36
3.66
16.46
14.33
30.78
6.00
13.41
4.27
8. 10
13-00
15.20
2.10
1 .52
2.44
1.22
.91
1.20
VOLUME
6 3
(10 M )
510.978
44.300
182.669
103.616
524.308
305.928
4921 .312
284.410
146.307
22.4B4
11 .312
96.579
160.264
25.080
70.069
12.340
4.774
204. 114
49.290
4988.265
347.841
3584.333
104.100
325.639
13.159
127.818
163.670
116.584
.882*
.154 •
.868
.602
: .141
: .144
RETENTION
TIME
(YEARS)
.619
2.255
.456
.705
.315
2.780
.617
.537
. 114
. 103
.040
.498
.098
. 154
.537
.035
.030
1 . 176
. 114
2.990
2.837
5.433
.548
3.230
.072
1 . 142
1 . 128
.401
.015
.066
.017
.002
.001
.001
MEDIAN
PHOSPHORUS
(MG/L)
.079
.122
.055
.040
.162
.023
.016
.079
.061
.046
.157
.057
.038
.176
.018
.106
.094
.008
.01 1
.005
.007
.004
.050
.010
.005
.01 1
.018
.023
.098
1.525
.052
.363
.535
.476
SECCHI
DISK
(M)
.9
.6
.5
.5
.8
.4
.7
.5
.1
.2
.8
.6
1-1
.6
1 .6
.6
1 .0
3.4
1.6
3.8
3.8
5.1
1 .1
2.6
3.2
3.0
2.5
1.8
1 .1
.4
.8
1.1
: .4
i 1 .4
MEAN.
CHL-A
(UG/L)
18.9
21 .4
5.6
8.3
11.3
8.9
3.8
14.9
12.9
17.8
20.5
38.4
6.8
22.0
4.9
33.4
28.3
3.2
2.0
1 .5
2.4
1.5
49.5
6.9
' 1.8
6.1
6.3
7. 1
26.2*
198.5
12.9
11.4
2.3
2.2
RESPONSE
TIME
(YEARS)
.0483
.3861
.0764
.4101
.0349
.5677
.261 1
. 1754
.0428
.0329
.0162
.3405
.0401
.0672
.2659
.0214
.0196
.4084
.0543
1 . 1 182
.9939
1 .6045
.2679
.9752
.0404
.2474
.3674
. 1936
.0086
.0129
.0076
.001 1
.0003
.0008
A31
-------
YEAR : 1972 TO 1975
TOTAL NUMBER OF LAKES
493
LAKE DATA
TETRA TECH.,INC.
3700 MT. DIABLO BLVD.
LAP., CA. 94549
STORET
NUMBER
2603
2606
2609
2617
2618
262S
2631
2643
2648
2653
2673
2683
2685
2688
2691
2692
2694
2695
2696
2698
27A1
27A2
27A5
27A6
27A7
2781
27B2
27B3
27B4
27CO
27C1
27C2
2702
2705
SURFACE ,
AREA
2
(KM )
6.42
1 .40
5.14
69.85
1.25
4.25
3.20
4.05
7.20
16.79
1.19
1 .66
2.12
10.40
2.81
.85
2.93
38. 85
81.12
1 .04
.78
4.25
2.47
23.92
33.22
6.54
21.88
3.82
3.86
6.11
25.98
.23
: 9.93
t 1.23
DRAINAGE
AREA
2
(KM )
3991 .10
129.20
2157.40
854.70
14.00
2108.20
52.60
383.30
463.60
6821.90
1261 .30
932.40
1383.00
1318.30
212.60
194.00
14.50
127.40
575.00
914.30
7.50
1771 .50
2206.60
96346.20
19942.60
66.00
357.40
318.60
453.20
1895.80
1631.70
3.10
: 381 .80
i 8.80
MEAN
DEPTH
(M)
3.35
6. 10
6.10
16.76
8.53
4.36
10.06
2.01
3.66
7.01
1 .52
4.27
.85
6QC
• OO
3.96
5. IB
4.24
14.94
2.32
6.74
1.34
8.53
5.50
2.44
8.78
1 .28
6.40
4.57
6. 19
7.92
9.75
1.31
1.07
2.59
VOLUME
6 3
(10 M )
21 .519
8.560
31 .330
1170.942
10.707
18.521
32.157
8. 141
26.347
117.736
1 .813
7.063
1 .813
71 .354
1 1 . 144
4.424
12.413
580.229
187.901
7.006
1 .042
36.299
13.585
58.319
291 .618
8.377
140.032
17.485
23.888
48.426
253.406
: .297
: 10.590
1 3.177
RETENTION
TIME
(YEARS)
.019
.221
.069
3.240
4. 134
.042
1 .866
.091
.212
.062
.006
.030
.005
. 153
.203
.086
3.310
15.582
1 .343
.036
2.917
. 100
.050
.006
.064
1 .380
3.698
.521
.871
.129
.736
.665
.200
: 1.872
MEDIAN
PHOSPHORUS
(MG/L)
.135
.061
. 122
.006
.032
.111
.378
.043
.159
.065
.035
.045
.047
.026
.369
.133
.009
.006
.016
.068
. 107
.050
.401
.240
.055
1 .000
.015
.040
.017
.025
.036
.408
.958
.136
SECCHI
DISK
(M)
.7
1 .1
.9
3.8
2.4
1 .1
1.5
1 .1
1.6
.9
1 .4
1 .1
2.1
1 .2
2.1
3.0
5.9
2.0
2.0
.5
1 .2
1 .5
.5
1 .1
.3
2.8
1 .4
2.6
1.4
2.2
.2
.2
.5
MEAN
CHL-A
(UG/L)
20.3
27.8
28.3
3.0
13.5
14.7
28.5
33.9
25.6
9.5
10.4
14.7
15.7
9.2
27.8
10.1
2.9
1 .0
9.2
11.1
58.6
17.2
12.5
21 .8
10.2
94.5
4.9 *
21 .4
11 .8
13.0
9.5
87.4
381 .2
49.5
RESPONSE
TIME
(YEARS)
.0101
. 1509
.0357
.8182
1 .0776
.0233
.6767
.0483
.0399
.0419
.0033
.0165
.0033
.0819
. 1054
.0536
.5998
3.2169
.44B2
.0194
.0958
.0607
.0153
.0043
.0298
.4129
.8298
. 1581
.4331
.0562
.3270
.0338
.0982
.5922
A32
-------
YEAR : 1972 TO 1975
TOTAL NUMBER OF LAKES
493
LAKE DATA
TETRA TECH.,INC.
3700 MT. DIABLO BLVD.
LAP., CA. 94549
STORET
NUMBER
2709
271 1
2712
2713
2715
2716
2719
2725
2737
2738
2746
2750
2756
2757
2761
2765
2776
2782
2783
' 2788
2793
2802
2804
2805
2806
2902
2903
2905
3001
3002
3003
3005
: 3007
: 3008
SURFACE
AREA
2
(KM )
51 .03
11.10
.74
6.11
63. 11
12.88
2.20
.69
38.61
33.39
453.25
4.50
.41
.66
2B.77
44.29
9.79
1.71
.34
10.58
7.65
52.49
121 .41
125.46
98.38
31 .65
100.77
1 7.81
142.45
19.97
475.60
51 .27
6.15
32.63
DRAINAGE
AREA
2
(KM )
3004.30
75.10
20.70
1 14.00
2926.60
450.70
1 16.50
16.30
766.60
1222.50
2693.60
61 .60
45.60
64.20
227.90
179.50
9563.90
5.70
38.30
293.40
42.00
1450.40
7770.00
4001 .50
3418.80
1592.80
3004.40
388.50
41191 .30
601 1 .40
18854.20
2408.70
76.80
443.90
MEAN
DEPTH
(M)
3.35
4.51
4.42
4.42
7.62
5.18
7.62
3.14
9. 14
.91
4.72
3.96
2.13
2.74
5.97
2.41
3.38
2.10
1 .92
12.13
15.24
15.50
3.70
16.50
16.50
9.50
7.30
4.10
17.40
15.80
13.50
8.20
8-50
45.70
VOLUME
6 3
(10 M )
171 .096
50.057
3.273
27.007
480.934
66.724
16.775
2. 173
353.022
30.532
2141 .320
17.847
.872
1 .821
171 .893
106.653
33. 120
3.591
.653
128.377
116.564
813.595
449.217
2070.090
1623.270
300.675
735.621
73.021
2478.630
315.526
6420.600
420.414
52.275
1491.191
RETENTION
TIME
(YEARS)
1 .652
4.215
.705
1 .368
.859
1 .366
1.132
.811
2.930
.371
5. 197
3.276
. 109
. 156
12. 748
3.263
.015
4.067
.097
2.380
17.404
1 . 122
. 134
1 .066
1 .095
.861
1 .062
1 . 169
.511
1 .022
.618
.471
17.449
3.201
MEDIAN
PHOSPHORUS
(MG/L)
.159
.038
.043
.209
.020
.028
.231
1 .380
.022
.302
.015
.050
.075
.040
.035
.032
.216
.600
.235
.013
.050
.062
.045
.041
.051
.043
.022
.082
.047
.049
.008
.022
.020
t .006
SECCHI
DISK
(M)
.0
.7
.6
.0
.9
.6
.9
.9
2.3
•*
2.2
.9
1.0
1 .4
1 .7
1 .7
.4
.3
.9
2.9
2.8
.9
.9
1.3
.6
1.3
1 .8
.3
1.5
2.6
5.9
3.4
3.3
7.9
MEAN
CHL-A
(UG/L)
16.5
14.5
12.8
38.0
8.7
14.1
10.7
'9.6
12.5
111.1
6.2
30.8
25.3
10.7
7.6
11.4
4.7
126. 1
21 .0
3.8
7.0
6.6
10.0
6.4
6.0
9.4
9.0
5.8
5.8
2.4
1 .3
4.1
4.7
.5
RESPONSE
TIME
(YEARS)
1 . 1345
1 . 2970
.0745
.4324
.2163
.2223
.4373
. 1997
1 .2617
. 1659
1 .6418
.5536
.0197
.0762
.8834
1 .2004
.0076
1.9119
.0302
.3466
.9716
. 1672
.0417
.6073
.6839
.3625
. 1597
.3502
. 1 960
.4168
.2808
.2760
5.5536
1 . 1708
A33
-------
YEAR : 1972 TO 1975
TOTAL NUMBER OF LAKES
493
LAKE DATA
TETRA TECH..INC.
3700 MT. DIABLO BLVD.
LAP., CA. 94549
STORET
NUMBER
3003
3010
301 1
3012
3013
3014
3016
3101
3102
3103
3104
3105
3106
3107
31 10
3201
3202
3204
3206
3302
3303
3305
3306
3402
3403
3406
3409
3410
3412
3415
: 341S
: 3420
! 3423
t 3501
SURFACE
AREA
(KM )
18.45
3.49
10.85
5.37 •
50.59
14.15
13.56
7.28
54.50
7.49
6.59
11.53
141 .64
2.99
20.13
592.88
19.69
46*. 14
9.71
1.51
180.43
.52
.61
1 .52
7.77
2.64
.57
.83
.38
10.87
.64
S.22
t 9.35
t 18.49
DRAINAGE
AREA
2
(KM )
378.40
1737.90
527.10
12760.90
4584.30
325.80
214.70
35042.70
1657.60
82S.80
66821 .90
8S.20
10204.60
434601 .80
9375.80
41699.00
1080.00
373.00
940.20
564.60
523.20
12.10
70.20
292.70
18.80
414.40
245.00
66.30
188.80
107.00
234.10
! 11370.10
MEAN
DEPTH
(M)
5.70
18.30
21 .90
68.90
15.30
6. 10
32.90
5.50
7.80
5.80
5.90
6. 10
19.80
3.70
7.30
59 . 1 0
6.70
4.60
15.80
2.47
13.11
2.26
3.35
1 .80
5.20
4-10
1 .80
1 .80
1 .40
5.50
1 .80
7.90
11.30
8.10
VOLUME
6 3
(10 M )
105. 165
63.867
237.615
369.993
774.027
86.315
446. 124
40.040
425. 100
43.442
38.881
70.333
2804.472
1 1 .063
146.949
35039.208
131 .923
212.244
153.418
3.717
2364.825
1 . 177
2.049
2.736
40.404
10.824
1.026
1 .494
.532
59.785
1.152
41.238
105.655
t 149.769
RETENTION
TIME
(YEARS)
1 .758
.348
.233
2.761
.871
.213
2.540
2.760
1 .357
.703
1.163
.075
2.387
2.923
1 .362
3.530
.252
1 . 160
.719
.018
4.110
.004
.008
.394
.949
.207
.088
.006
.005
1 .708
.012
.812
2.864
1.714
MEDIAN
PHOSPHORUS
(MG/L)
.029
.015
.010
.01 1
.018
.051
.008
.044
.112
.064
.061
.075
.027
.060
.067
.016
. 198
.095
.058
.033
.006
.024
.028
.082
.021
.055
.070
.071
.082
.022
.133
.020
.014
.025
SECCHI
DISK
(M)
1.1
3.5
5.5
4.1
1.3
.7
5.3
1 .1
.6
.8
.8
.6
2.3
1.2
.9
5.9
.7
.8
3.1
1.2
5.6
1.8
1 .7
.7
2.2
n
.9
.9
.9
2.1
1.0
1.8
3.7
.8
MEAN
CHL-A
(UG/L)
7.2
2.2
3.3
2.1
2.8
16.9
1 .4
17.0
27.8
14.4
16.6
26.1
8.6
15.4
14.4
3.1
4.6
4.9
7.5
6.2
2.1
7.0
3.8
48.5
11 .9
22.3
39.0
23.0
6.8
13.6
7.0
15.3
7.1
5.9
RESPONSE
TIME
(YEARS)
.2131
. 1496
.0936
1 .4191
.2591
.0181
.7728
.3752
. 191 1
.0286
. 1469
.0350
.3294
.5103
.3187
. 1632
.0903
.4083
.2330
.0110
.6578
.0019
.0037
.2294
.3307
.0964
.0245
.0017
.0012
.6481
.0070
.3368
1.7723
. 1514
A34
-------
YEAR : 1972 TO 1975
TOTAL NUMBER OF LAKES
493
LAKE DATA
TETRA TECH.,INC.
3700 MT. DIABLO BLVD.
LAP., CA. 94549
STORET
NUMBER
3502
3503
3505
3506
3507
350S
3604
3605
3606
3608
361 1
3617
3632
3633
3635
3637
363S
3640
3641
3701
3702
3704
3705
3706
3707
371 1
3713
3715
3716
3717
3718
: 3719
> 3801
t 3804
SURFACE
AREA
2
(KM )
7.07
38.83
148.05
13.07
23.05
16.79
42.99
19.42
26. 13
171.97
8.81
47.40
122.00
16.32
175.34
3.47
1 2.89
1.B7
48.77
24.17
10.36
43. 18
16.63
64.29
25.41
13.09
131.57
14.22
1 1 .59
21.29
1.38
36.17
21.98
40.06
DRAINAGE
AREA
2
(KM )
520.60
19189.30
76275.40
2012.40
44004. 10
28852.60
476.60
1175.80
2261 .00
2033. 10
8031 .40
471 .40
2703.90
631 .90
1823.30
382.50
180.50
54.90
5646.20
10818.40
17793.30
4068.90
3392.90
10360.00
2507.10
4822.60
4636. 10
2823.10
455.80
12090.10
1178.40
251 .20
4946.90
6417.50
MEAN
DEPTH
(M)
6.70
11 .80
18.30
18.30
2.10
8.00
39.01
19.20
5.39
54.56
5.49
22.56
7.59
7.92
88.70
13.41
8.90
5.12
14.40
14.20
11 .60
41 .30
9.50
4.90
21 .30
5.40
10.20
6.34
16.80
9.70
22.70
1 .50
4.00
3.40
VOLUME
6 3
(10 M )
47.369
458. 194
2709.315
239. 181
48.405
134.320
1677.374
373.004
140.995
9382.813
48.313
1069. 133
925.893
129.308
15552.263
46.566
1 14.716
9.553
702.288
343.214
120.176
1783.334
157.985
315.021
541 .233
70.686
1342.014
90. 155
194.712
206.513
31.326
54.255
87.920
136.204
RETENTION
TIME
(YEARS)
5.777
3.040
2.243
.889
.221
1 .356
14.663
.575
. 104
11 .258
.018
7.840
.454
.411
33.745
.252
1 .673
.303
.21 1
.077
.018
.490
.090
.073
.318
.033
.653
.059
.441
.042
.041
.662
.832
1.371
MEDIAN
PHOSPHORUS
(MG/L)
.036
.020
.083
.034
.097
.021
.009
.046
.010
.014
.076
.008
.009
.025
.010
.057
.020
.017
.016
.042
.090
.01 1
.047
.090
.015
.018
.019
.061
.011
.040
.103
.018
.260
.274
SECCHI
DISK
(M)
.5
1 .2
.6
.9
.3
1 .3
4.5
1.8
2.3
2.8
1 .3
3.6
3.5
2.5
4.0
1 .3
3.2
1.2
2.2
.8
.6
2.7
1.0
.6
2.0
1 .0
1.3
.9
3.4
.8
.8
1.1
.7
.6 !
MEAN
CHL-A
(UG/L)
3.9
3.3
6.8
2.2
14. 1
3.2
4.3
29.9
3. 1
3.2
19.5
5.7
4.8
11.8
6.1
28.7
9.9
• 7.9
3.7
7.2
4.2
3.4
7.3
14.3
5.7
5.6
5.8
3.6
5.4
6.8
3.8
3.6
40.9
60.1
RESPONSE.
TIME
(YEARS)
3. 2089
. 1258
.051 1
.2859
. 1062
.0917
3.5184
. 1 163
.0520
3.7284
.0096
2.5721
. 2300
. 1322
4.6582
.0720
.4951
. 1864
.0923
.0417
.0068
. 1790
.0437
.0232
. 1208
.0175
. 1455
.0215
.2057
.0243
.0140
.2666
.4628
.5317
A35
-------
YEAR : 1972 TO 1975
TOTAL NUMBER OF LAKES
493
LAKE DATA
TETRA TECH.,INC.
3700 MT. DIABLO BLVD.
LAP., CA. 94549
STORET
NUMBER
3607
380S
3812
3814
3901
3902
3905
3906
3907
3908
3912
3914
3921
3924
3927
3928
3929
3930
3931
3932
4001
4002
4003
4004
4005
4006
4008
4009
4010
4011
4012
4013
4014
41 at
SURFACE
AREA
2
(KM )
2.00
.53
1490.21
1 .10
1.70
12.71
5.46
5.17
5.26
5.36
.76
1 1 .43
31 .57
3.44
44.52
6.23
B.90
.91
3.35
8.17
25.41
9.51
22.66
414.81
16.47
7.61
2.31
188.18
10.12
106.43
119.22
51 .19
24.56
56.66
DRAINAGE
AREA
2
(KM )
357.40
227.90
469825.80
393.70
777.00
1 14.50
562.00
717.40
999.70
1921 .80
68. 10
492.10
252.50
510.20
290.40
181 .00
642.30
35.70
2535.60
295.30
5480.40
326.30
642.30
97958.90
787.40
3869.50
1644.60
26671 .50
25.10
162673.40
11237.70
4169.90
: 662.30
: 188033.90
MEAN
DEPTH
(M)
5.00
4.20
18.90
2.90
1.20
1 ,90
1 .70
5.00
3.30-
3.00
1 .90
6.50
2.70
4.80
3.00
4.70
4.90
3-90
4.80
5. 10
6.40
9.40
5.10
10. 10
6.40
11 .90
1 .80
10.90
9. 10
7.70
5.70
15.50
6.00
31.60
VOLUME
6 3
(10 M )
10.000
2.226
28164.969
3. 190
2.040
24. 149
9.282
25.850
17.358
16.080
1 .444
74.295
85.239
16.512
133.560
29.281
43.610
3.549
16.080
41 .667
162.624
89.394
115.566
4189.581
105.408
90.559
4. 158
2051 . 162
92.092
819.511
679.554
793.445
147.360
1790.456
RETENTION
TIME
(YEARS)
1 .865
.642
1 .576
.506
.009
.638
.055
.114
.063
.025
.065
.481
1 . 126
. 103
.784
.464
.223
.281
.024
.389
2.079
3.221
1 .393
.846
7.597
1 .595
.009
.354
2.950
.150
.298
.657
14.602
.108
MEDIAN
PHOSPHORUS
(MG/L)
.438
.228
.016
.092
.122
.179
.127
.098
.086
.163
.1 13
.040
.058
.036
.148
.031
.042
.125
.208
.067
.041
.020
.037
.081
.038
.070
.142
.087
.057
.136
.059
.039
.027
.079
SECCHI
DISK
(M)
2.0
.6
2.3
1.5
.3
.2
4
.7
.4
.5
.3
.9
.9
1 .1
.4
1.0
.9
.9
.6
.7
.8
1.4
1 .0
.4
1.2
.4
.4
-;8
1.0
.4
.4
1.6
.9
1.8
MEAN
CHL-A
(UG/L)
19.7
2.7
6.9
39.0
10.9
186.6
67. 1
9.9
10.9
27.4
40.5
13.0
36.3
22.8
79.2
16.4
15.5
55.4
5.5
38.0
14.8
7.0
8.4
4.4
15.0
9.7
8.0
6.8
5.7
21.4
5.1
6.6 .
8.4
16.2
RESPONSE
TIME
(YEARS)
.7555
.2825
.0750
. 1905
.0052
.401 1
.031 1
.0627
.0254
.0083
.0383
. 1 168
.4220
.0558
.3750
.1118
.0371
.0379
.0106
.0791
.5237
.5157
.8163
.3668
.3302
.8850
.0048
. 1286
.4254
.0462
.0801
.2465
.5642
.0402
A36
-------
YEAR : 1972 TO 1975
TOTAL NUMBER OF LAKES
493
LAKE DATA
TETRA TECH.,INC.
3700 MT. DIABLO BLVD.
LAP., CA. 94549
STORET
NUMBER
4104
4106
4107
4201
4204
4207
4213
4216
4219
4220
4221
4222
4223
4224
4225
4226
4227
4229
4402
4403
4503
4504
4505
4506
4507
4508
451 1
4513
: 4515
: 4602
: 4603
: 4610
t 4620
: 4624
SURFACE
AREA
(KM )
1 1 .07
5.66
1 .09
7.00
3. 78
3.29
66.45
14.41
4.. 55
3.83
.69
2.67
3.04
2.02
4.38
1 .38
3.04
23. 3t
.84
1.04
13.64
46. 14
226.43
447.59
205.58
8.68
53.10
69.41
2.25
.44
19.55
1.68
3.48
3.35
DRAINAGE
AREA
(KM )
1007.50
188810.90
57.50
878.00
69.70
182.20
398.90
1512.60
1 10.60
249.70
20.40
17.30
36. 10
49.50
559.40
45.60
193.70
590.50
232.30
138.60
9867.90
2978.40
5407.90
38073.00
6268.00
448. 10
7821 .80
1137.00
753.70
1 14.00
23569.00
248.60
828.80
450.70
MEAN
DEPTH
(M)
39.20
11.40
9.90
1 .60
7.30
5.00
3.70
2.50
7.30
12.80
8-80
11 .00
4.30
.90
3-40
2.70
3.70
B.50
2.44
1.52
5.40
6.80
13.90
4.00
12.70
4.30
7.00
15.20
4.00
3.70
9. 10
10.50
16.40
4.60
VOLUME
6 3
(10 M )
433.944
64.524
10.791
1 1 .200
27.594
16.450
245.865
36.025
33.215
49.024
6.072
29.370
13.072
1.818
14.892
3.726
11 .248
198. 135
2.043
1 .575
73.656
313.752
3147.377
1790.360
2610.866
37.324
371 .700
1055.032
9.000
1 .628
177.905
17.640
57.072
15.410
_/-
RETENTION
TIME
(YEARS)
.416
.004
.238
.030
.292
.137
1 .392
.057
.301
.379
.241
1 .552
.829
.058
.039
. 197
.102
.628
.015
.019
.018
.201
.833
. 121
.955
. 181
. 107
1 .061
.016
.890
1.454
1 .998
1 .645
48.865
MEDIAN
PHOSPHORUS
(MG/L)
.038
.071
.031
.064
.023
.066
.070
.058
.009
.010
.020
.015'
.008
.014
.040
.027
.024
.015
.032
1 . 135
.143
.061
.013
.055
.024
.014
.045
.008
.046
.067
.019
.033
.011
.187
SECCHI
DISK
(M)
1.7
1.9
10.3
1 .2
2.5
1.0
.8
.9
2.9
3.5
1.6
4.1
2.6
1.5
.7
1.2
1.5
2.7
1.3
«y
A
.9
2.0
• •
1.9
1 .1
^ g
3.3
.6
1.5
2.0
5.0
6.4
2.3
MEAN
CHL-A
(UG/L)
2.3
10.3
9.2
15.2
7.6
24.0
56.3
26.8
5.2
4.9
19.2
6.0
5.2
5.5
11.8
14.0
5.0
9.6
8.1
22.9
2.8
8.2
6.2
8.7
. 6.4
8.6
5.4
2.8
1 .5
4.7
3.7
3.6
1.5
18.5"
RESPONSE
TIME
(YEARS)
.2560
.0023
. 1 197
.0108
. 1407
.0207
.4755
.0293
.0355
. 1852
. 1 153
.3074
.3032
.0363
.0237
.1181
.0632
.361 1
.0084
.0087
.0111
.0315
. 1035
.0359
. 1846
. 1247
.0292
.5727
.0066
.2802
. 1073
1 .1841
. 1260
2.6973
A37
-------
YEAR : 1972 TO 1975
TOTAL NUMBER OF LAKES
493
LAKE DATA
TETRA TECH.,INC.
3700 MT. DIABLO BLVD.
LAF., CA. 94549
STORET
NUMBER
4626
4627
462S
4704
4707
4708
471 1
4712
4713
4717
4722
4723
4724
4725
4728
4601
4802
4803
4805
4806
4808
4809
4810
4811
4812
4813
4814
4815
4816
4817
4818
4819
4820
1 4821
SURFACE
AREA
2
(KM )
3.10
1 .56
2.23
17.80
122.62
143.25
123.03
59.09
12.38
41 .97
157.82
57.47
42.90
30.68
16.11
262.48
3.67
50.27
29.54
93.32
13.96
33.35
6.52
88.63
13.84
36.42
10.93
93.93
62. 17
49.53
75.27
86.43
: 334.28
: 25.80
DRAINAGE
AREA
2
(KM )
10308.20
230.50
1036.00
4765.60
8878.50
53846. 10
11766.40
24734.50
4346.00
56643.30
44832.90
2310.30
1370.10
1820.80
681 .20
318828.90
24.60
9230.80
3975.60
80937.40
174.60
3719.20
834.00
43149.40
5710.90
5102.30
1238.00
4299.40
5402.70
7324.50
2201 .50
1994.30
42950.00
93991 .10
MEAN
DEPTH
(M)
.80
10.20
3.70
13.30
14.90
5.40
14. 10
7.60
5.00
7. 10
7.90
8.50
15.20
26.40
5.70
16.50
5.60
10.80
6.00
13.10
5.50
14.00
6.00
4.20
3.70
6.40
5.60
6.00
5.30
3.70
4.10
6.50
6.50
6.70
VOLUME
6 3
(10 .M )
2.480
15.912
8.251
236.740
1827.038
773.550
1734.723;
449.084
61 .900
297.987
1246.778
488.495
652.080
809.952
91 .827
4330.920
20.552
542.916
177.240
1222.492
76.780
466.900
39. 120
372.246
5 1 . 208
233.088
61 .208
563.580
329.501
183.261
308.607
561 .795-
2172. B20
172.860
RETENTION
TIME
(YEARS)
.033
3.604
2.907
.114
.500
.026
.302
.038
.023
.010
.053
.382
.903
1 .014
.233
3.796
5. 172
1 .006
1 .544
1 .680
20.289
1.872
3.877
.480
.428
.992
2.231
1 .021
2.816
.153
.606
1.643
.360
.153
MEDIAN
PHOSPHORUS
(MG/L)
.489
.053
.21 1
.052
.051
.031
.026
.054
.020
.051
.032
.056
.021
.014
.017
.013
.022
.016
.027
.036
.038
.010
.042
.113
.025
.024
.060
.045
.023
.097
.031
.063
.196
.042
SECCHI
DISK
(M)
.7
2.7
.7
1.5
1.3
.9
1.5
.9
1.4
1.0
.9
1 .8
2.6
2.4
1 .8
3.3
2.0
3.1
.8
1.6
1 .0
2.9
.7
.6
.8
.8
.6
.6
1 .1
.4
1.5
.4
.9
1 .1
MEAN
CHL-A
( UG£L )
65.8
15.4
100.8
11.4
12.2
3.1
4.6,.
4.8
4.0
' 2.7
5.6
10.0
6.7
7.7
7.4
2.0
12.4
8.0
4.9
8.6
22.5
2.5
12.7
19.8
15.9
5.7
6.3
14.2
10.2
16.6
12.9 *
5.4.
16.1
8.1
RESPONSE
TIME
(YEARS)
.0178
1 .4324
.3651
*• .0408
. 1282
.0154
.0875
.0198
.0083
.0061
.0286
.2365
. 3852
. 1078
. 1256
. 1467
.3701
.061 1
.3718
.2017
.2380
.7826
2.6641
. 1323
.2309
. 1 164
.5926
.2225
.5946
.0610
.0983
.2551
. 1067
.1026
A38
-------
YEAR : 1972 TO 1975
TOTAL NUMBER OF LAKES
493
LAKE DATA
TETRA TECH.,INC.
3700 MT. DIABLO BLVD.
LAF., CA. 94549
STORET
NUMBER
4822
4823
4824
4825
4826
4827
4828
4829
4830
4831
4832
4834
4835
4837
4838
4833
4901
4903
4904
4906
4908
490S
4910
4913
4914
4915
4917
4920
4921
4923
4924
4925
t 5001
: 5002
SURFACE
AREA
2
(KM )
22.56
66.77
103.44
80.13
21 .85
463.48
25.62
46.38
19.00
26.02
148.52
360. 18
76.61
36.50
7.32
95.35
171 .59
9.66
5.95
10.12
4.74
4.01
3.12
10.20
4.99
6.88
10.15
44.52
11.17
.73
396.60
40.47
1130.27
.57
DRAINAGE
AREA
2
(KM )
1642.10
41564.30
2201 .50
58404.50
3853.90
8932.90
40766.60
2610.70
932.40
3413.60
1957.90
87500.50
98756.60
6594. 10
2007.20
67780.20
1030.80
1450.40
1895.90
57.00
378. 10
1320.90
290. 10
- 984.20
121 .70
25.90
6319.60
13260.80
2745.40
217.60
6876.40
62.20
21185.80
362.60
MEAN
DEPTH
(M)
13.90
16.00
4.90
11 .20
6.50
7.70
6.70
4.30
3.50
11 .30
7.70
5.70
18.90
6.30
6.50
8. 10
10.20
19.90
15.30
25.90
16.30
5.60
14.10
6.30
6.40
3.00
10.10
6.50
19.90
3.00
2.10
5.90
19.39
3.35
VOLUME
6 3
(10 M )
313.584
1068.320
506.856
897.456
142.025
3568.796
171 .654
199.434
66.500
2O4.026
1 143.604
2053.026
1447.929
229.950
47.580
772.335
1750.218
192.234
91 .035
262. 108
77.262
22.456
43.992
64.260
31 .936
20.640
102.515
289.380
222.283
2.190
832.860
: 238.773
i 21910.654
! 1.900
RETENTION
TIME
(YEARS)
2.709
8.576
1 .330
1 .008
8.340
2.670
7. 162
.960
2.478
1 .338
3.221
.475
1 .020
14.881
12.573
.534
21 .936
.578
.367
58.531
.869
.727
.382
1 .418
2. 173
36.361
.661
1 .636
2.031
. 156
2.487
3.236
2.220
.010
MEDIAN
PHOSPHORUS
(MG/L)
.010
.021
.031
.023
.098
.029
.036
.053
.073
.018
.046
.042
.018
.029
.020
.028
.01 1
.038
.047
.023
.012
.192
.008
.067
.071
.044
.047
.026
.016
.021
.132
.044
.018
.021
SECCHI
DISK
(M)
2.5
1 .5
1.5
2.1
.5
1.5
1 .0
.7
.4
2.4
.9
1.2
2.8
1.2
1 .7
1 .8
6.3
1 .8
1 .3
8.8
2.5
1.4
3.0
1.2
1.9
1.6
.4
1.3
2.7
1.9
.2
1 .1
2.3
1.7
MEAN
CHL-A
(UG/L)
12.9
3.0
10.6
9.5
24.7
6.3
11 .8
24.5
18.5
3.9
18.2
12.5
5.6
8.7
4.3
6.9
Q
9. 1
7.0
12.5
2.5
33.6
2.7
1 1 .8
46.0
6.3
25.3
18.2
5.7
7.2
72.0
7.6
11.1
7.5
RESPONSE
TIME
(YEARS)
.7515
.0237
. 11 84
.0960
4.7878
1 .0650
.2520
.4456
. 1438
.3387
.2689
.1312
.3870
4. 1379
1 .2232
.0899
5.0555
.2610
. 1728
17.3684
.4154
.3835
.2605
.6552
1 . 1061
1 . 1064
.2398
.1366
. 1289
.0938
1 . 1891
1 .9714
.4289
.0058
A39
-------
YEAR : 1972 TO 1975
TOTAL NUMBER OF LAKES
493
LAKE DATA
TETRA TECH.,INC.
3700 MT. DIABLO BLVD.
LAP., CA. 94549
STORET
NUMBER
5005
5007
5008
5010
501 1
5103
5105
5106
5103
5110
5111
51 12
51 13
5306
5309
531 1
5312
5401
5402
5403
5404
550S
5513
551S
5520
5522
5531
5538
553S
5541
i 5546
i 5548
1 5550
1 S555
SURFACE
AREA
2
(KM )
8.84
.62
94.57
3.34
3.60
18.19
4.63
198.25
6.88
80.94
12.95
6.07
1 .82
10.36
27.58
19.82
20.25
8.25
7.00
1 1 .02
7.08
4.07
7.18
29.73
10.99
42.41
4.15
44.48
24.9J
9.31
6.85
.61
4.80
! 36.02
DRAINAGE
AREA
2
(KM )
486.40
694. 10
1779.30
1815.60
290.10
6138.30
572 .40
20150.20
1533.30
2652.90
e 3457.60
774.40
673.40
141 .70
7990.10
253.00
145.30
11924.40
3654.50
2082.40
3537.90
1 18.60
105.20
303.00
994.50
6474.90
115.50
10100.80
194.00
986.80
4351 .10
12.20
256.70
23180.10
MEAN
DEPTH
(M)
10.36
1 .68
15.54
3.14
12.68
29.00
18.00
10.70
4.90
35. 10
7-00
4.90
6. 10
18.70
5.90
17.70
1 .80
5.80
12.80
21 .00
17.40
4.27
7.62
31 .70
5. 18
1 .62
9.91
2. 13
3.23
1 .40
4.05
3.78
5.27
1 .83
VOLUME
6 3
(10 M )
91 .593
1 .038
1470.084
10.494
45.668
527.510
83.340
2121 .275
33. 712
2840.994 -
90.650
29.743
11 . 102
193.732
162.722
350.814
36.450
47.850
89.600
231 .420
123.192
17.372
54.705
942.359
56.952
68.512
41 . 130
94.909
80.489
13.050
27.758
2.294
25.308
65.868
RETENTION
TIME
(YEARS)
.213
.003
1 .709
.010
.227
. 172
.322
.340
.074
3.183
.084
. 1 19
.045
.603
.796
1 .746
.257
.009
.032
. 137
.054
.401
2.810
20.980
.372
.064
1 .535
.036
1 . 533
.089
.028
.694
.532
.010
MEDIAN
PHOSPHORUS
(MG/L)
.009
.018
.021
.015
.007
.031
.011
.044
.098
.016
.044
.066
.079
.007
.115
.015
.009
.074
.006
.011
.006
.073
. 141
.028
.115
.361
.124
.074
.020
.404
.111
.078
.043
.058
SECCHI
DISK
(M)
2.8
1 .5
2.0
1.6
2.4
1.5
2.1
1 .1
1.0
2.0
.9
1 .1
1 .0
5.6
.9
3.2
5.4
.7
2.4
3.5
3.1
1 .0
1.3
5.8
1 .1
.5
1 .9
.5
2.1
.2
1.4
.8
1.8
.8
MEAN
CHL-A
(UG/L)
1 .8
3.5
14.0
8.5
5.2
5.6
6.0
8.8
12.4
1 1 .6
12.6
13.6
6.7
1.4
29. 1
7.3
3.4
14.9
4.7
6.2
1 .2
6.8
43.9
4.8
30.9
36. 1
12.0
19.4
11.9
169.3
13.7
5.1
16.6
51.4
RESPONSE
TIME
(YEARS)
.1216
.0015
.6806
.0049
. 1 193
.0581
.0660
.0434
.0195
. 1208
.0545
.0648
.0202
. 1549
.3038
.8748
.1012
.0059
.0089
.0854
.0339
.2677
.8649
7.8990
.2484
.0350
.4574
.0239
.8088
.0608
.0166
.2389
.2083
.0066
A40
-------
YEAR : 1972 TO 1975
TOTAL NUMBER OF LAKES
493
LAKE DATA
TETRA TECH.,INC.
3700 MT. DIABLO BLVD.
LAP., CA. 94549
: STORET
: NUMBER
:
5556
555S
5564
5565
5570
5574
5601
5602
5603
5605
5606
5607
5608
5609
5610
5613
5614
N
MEAN
S.D.
MAX.
: STR. NO.
: MIN.
1 STR. NO.
SURFACE
AREA
2
(KM )
21 .97
4.59
4.70
27.64
.95
20.78
8.34
7.03
69.84
137.67
20.23
53.97
38.02
24.68
48.77
7.08
51 .34
493
44.09
109.90
1490.21
3812
.10
1005
DRAINAGE
AREA
2
(KM )
14374.20
922.00
36.50
945.30
253.30
846.90
1139.60
336.70
19945.60
39109.00
295.30
50523. 10
5180.00
28979.50
2030.60
50937.50
489
11608.21
46951 .98
469825.80
3812
3.10
27C2
MEAN
DEPTH
(M)
8.81
1 .92
5.61
4.75
1.22
4.57
5.80
12.20
10.40
33.90
24.40
1.8 . 30
6.50
4.20
25.60
4.90
26.80
493
9.20
9.68
88.70
3635
.50
2220
VOLUME
6 3
(10 M )
193.531
8.804
26.350
131 .444
1 .155
94.990
48.372
85.766
934.336
4667.013
493.612
987.651
247. 130
103.656
1248.512
34.692
1375.912
493
638.685
2510.579
35039.208
3201
.110
1005
RETENTION
TIME
(YEARS)
.046
.052
3.598
.432
.031
.327
.749
.497
.741
2.342
2.484
.723
15.246
4.383
.936
. 160
.433
493
1 .745
4.869
58.531
4906
.001
2508
MEDIAN
PHOSPHORUS
(MG/L)
.043
.269
.013 '
.071
. 190
.029
.087
.008
.037
.014
.006
.045
.028
.043
.030
.069
.026
493
.084
.150
1 .525
2502
.004
2311
SECCHI
DISK
(M)
1.0
• 6
2.3
g
g
1 .1
• 3
3.5
.9
3.4
13.3
1.0
1.2
.6
1.4
.8
3.4
493
1.7
1.5
13.3
5606
.1
0502
MEAN
CHL-A
(UG/L)
5.0
44.7
8. 1
35.5
65.3
9.2
4.4
2.5
6.3
5.6
3.8
8.5
• 7.8
7.5
2.5
13.0
5.4
493
17.304
29.512
381 .200
2702
.500
3008
RESPONSE
TIME
(YEARS)
.0270
.0208
1 .8399
.2224
.0183
.2033
.4388
.2216
.0486
.2117
1 .3577
. 1401
. 1272
.3296
. 1790
.0451
.Ot91
493
.4047
1 .0772
17.3684
4906
.0003
2508
N « NUMBER OF LAKES WITH NON-ZERO DATA
A41
-------
PHOSPHORUS LOADING 1972-1975
A42
-------
PHOSPHORUS LOADING
TETRA TECH.,1NC.
3700 MT. DIABLO BLVD.
LAP., CA. 94549
YEAR : 1972 TO 1975
TOTAL NUMBER OF LAKES : 493
STORET
NUMBER
0101
0104
0105
0107
0112
0115
0403
0404
0405
0406
0409
0410
041 1
0501
0502
0504
0505
.0506
0507
0508
0510
0514
0515
0516
0601
0602
0606
0608
0611
0614
0616
0620
0621
! 0624
1 0625 i
MUNICIPAL
(KG/YR) (X)
458830 70
53115 3
61930 29
254S90 22
7940 55
7490 3
105 IB
1425 15
10 1
15050 12
1565
45860 56
1475 1
42410 54
1375 12
2615 11
36190 50
590 2
214095 83
4020 10
2610 68
10625 19
4760 1
5 1 1
SEPTIC TANK
(KG/YR) (X)
20
75
10
30
130
5
25
5
10 1
10
5
35
15
5
30
75
10
35
25
5
50 8
5
5
10
5 1
INDUSTRIAL
(KG/YR) (X)
660
•
.
RIVERS
(KG/YR) (%)
187660 29
1751480 95
223845 99
140105 66
888335 77
5420 37
272195 97
370 65
7775 80
247325 98
565 81
104680 83
475170 97
26910 33
110960 99
93455 91
35975 46
129285 91
7615 65
20330 84
30485 43
18865 67
37730 15
20555 52
860 23
2960 -88
19305 35
360 57
3677B5 99
2000 47
28240 90
745 48
330295 91
34750 93
590 66
DIRECT RUNOFF
(KG/YR) (X)
4140 1
37935 2
2280 1
8520 4
10080 1
1050 7
660
90 16
425 4
3780 1
105 15
5700 5
14325 3
7230 9
1 140 1
4995 5
300
12870 9
1780 15
805 3
4530 6
5765 21
4510 2
11930 30
320 8
350 10
24080 44
125 20
4955 1
2205 52
2980 10
735 48
27470 8 .
2570 7
275 31
PRECIPITATION
(KG/YR) (X)
650
4810
235
2760 1
2140
75 1
1350
5 1
100 1
1850 1
5 1
1060 1
920
2000 2
30
3220 3
135
375
950 8
495 2
425 1
2840 10
3050 1
2870 7
25 1
70 2
920 2
100 16
60
65 2
140
55 4
2090 1
90
20 2
TOTAL
2
(KG/YR) (G/M /YR)
651300 17.49
1848075 6.72
226370 16.94
213345 1.35
1155275 9.45
14490 3.37
281720 3.64
570 1.90
9725 1.72
252960 2.39
695 2.17
126490 2.08
491980 9.35
82010 .72
112135 69.22
103180 .56
78835 10.04
142535 6.64
,. 1 1750 .22
24245 .86
71705 2.95
28070 .17
259420 1.49
39400 .24
3815 2.45
3380 • .83
54935 1.05
635 .11
372800 109.97
4275 1.12
31360 3.96
1540 .48
364615 3.05
37420 7.34
895 .84
FLOW
(CMS) (M/YR)
.__
178.63 151.310
1153.16 132.245
191.39 451.772
133.80 26.751
252.56 65.167
2.33 17.088
260.69 106.353
.08 8.410
.51 2.837
317.53 94.799
.10 9.855
28.42 14.765
8.68 5.203
42.35 11 .695
4.25 82.733
168.02 28.814
65.82 264.420
13.82 20.318
19.50 11.386
10.51 11 .699
62.53 81.217
45.16 8.776
116.90 21.151
49.52 9.528
1.20 24.258
5.23 41.545
46.86 28.175
1.51 8.340
74.48 692.862
.27 2.241
10.40 41.411
.65 6.446
295.38 78.016
51.59 319.008
1.30 38.315
A43
-------
YEAR : 1972 TO 1975
TOTAL NUMBER OF LAKES
493
PHOSPHORUS LOADING
TETRA TECH.,INC.
3700 MT, DIABLO BLVD.
LAP., CA. 94549
STORET
NUMBER
0626
0801
0803
0804
0806
0807
0808
0812
0901
0904
0905
0910
0911
0912
1005
1007
1008
1009
1010
1301
1302
1303
1304
1309
1310
131 1
1313
1316
1317
1318
1319
1601
1602
1603
: 1604
MUNICIPAL
(KG/YR) (X)
455 45
3160 3
2365 30
920 9
895 14
2510 2
28263 21
11376 65
29678 52
10156 7.
75033 28
2995 41
475 19
2155 44
26595 27
34065 10
460 4
90520 20
426005 66
78100 49
555 4
13285 5
31190 2
12495 64
58095 10
1520 4
13580 • 8
! 570
SEPTIC TANK
(KG/YR) (X)
10 1
10
5
10
45
10
10
14
14
10
5
5
5
1
60
140
70 1
75
415
410
35
360
325
215 5
5
t
t 250
t
INDUSTRIAL
(KG/YR) (X)
108130 18
RIVERS
(KG/YR) (X)
615 74
500 50
85485 88
4880 99
3720 48
9190 B8
4735 72
123165 78
104082 77
5837 33
26799 47
139346 90
1BB529 70
116584 99
4015 55
1210 49
2585 53
2125 96
345 91
67845 68
300300 89
8415 74
343500 76
212645 33
60605 38
8550 65
" 231970 91
11230 92
1354980 97
3525 79
6545 33
431560 71
27085 67
157535 88
: 91195 79
DIRECT RUNOFF
(KG/YR) (X)
185 22
20 2
8265 8
5
1450 19
135 1
795 12
31300 20
2731 2
286 2
77
5230 3
5271 2
1651 1
290 4
755 31
120 2
85 4
30 8
4070 4
1970 1
1870 17
11545 3
2065
16695 11
3615 28
9365 4
73b 6
3480
520 12
515 3
7380 1
10065 25
6185 3
22205 19
PRECIPITATION
(KG/YR) (%)
25 3
30 3
640 1
55 1
225 3
130 1
150 2
1105 1
23
5
5
68
136
23
5
10
5
5
5 1
840 1
605
505 4
4960 1
340
2825 2
305 2
1090
235 2
415
195 4
45
4850 1
1875 5
2265 1
1345 1
TOTAL
2
(KG/YR) (G/M /YR)
835 .55
1005 .59
97560 2.66
4945 1.53
7770 .61
10420 5.08
6585 '.77
158090 2.50
135113 100.26
17518 54.11
56559 218.37
154800 39.23
268969 34.98
118258 89.09
7315 73.15
2455 3.84
4870 32.47
2220 6.53
381 1.73
99410 2.07
337080 9.78
11320 .39
450600 1 .59
641470 33.38
158635 .98
13060 .75
256070 4.12
12200 -.91
1390390 58.74
4455 .40
19605 8.07
610015 2.20
40545 .38
179815 1.39
115315 1.50
FLOW
(CMS) (M/YR)
1.70 35.271
1 .50 29.310
47.65 41.035
.15 1.460
7.63 18.857
13.27 204.138
13.46 49.358
49.46 24.660
35.4'J 829.046
5.31 523.300
4.83 585.842
70.15 560.063
62.66, 256.963
71.79 1702.233
.7'J 249.134
.42 20.695
.33 69.379
1 .53 141.912
• .53 75.973
50.60 33.244
136.20 124.643
12.00 13.076
264.42 29.435
49.60 81 .383
60.50 11.816
11.40 20.709
89.30 45'. 298
16.30 38.247
185.80 247.545
9.60 26.959
7.50 97.333
222.29 25.305
29.64 8.716
176.52 42.986
161.71 66.324
A44
-------
YEAR : 1972 TO 1975
TOTAL NUMBER OF LAKES : 493
PHOSPHORUS LOADING
TETRA TECH.,INC.
3700 MT. DIABLO BLVD.
LAP., CA. 94549
STORET
NUMBER
1608
1609
161 1
1612
1613
1703
1706
1712
1714
1725
1726
1735
1739
1740
1742
174B
1750
1751
1754
1755
175B
1761
1762
1763
1764
1766
1B05
181 1
1827
182B
1829
1836
1837
1839
: 1840
MUNICIPAL
(KG/YR) (X)
-
8770 22
170 4
9480 3
20880 26
8390 8
21185 87
985 5
15130 20
37115 20
85 1
8070 28
8805 30
. 25985 71
630 55
2360 48
21380 13
5135 53
135 9
85 2
60 1
90 4
635 2
6195 30
46785 29
2470 21
11600 32
125 9
240 10
625 24 1
SEPTIC TANK
(KG/YR) (X)
10
5
15
120 6
120 6
30 1
20
15
60
15
5
195 1
545 1
640
15
30 1
5
25 1
10
55
20
20
5
135 10
40 2
5
15 1
INDUSTRIAL
(KG/YR) (X)
20
1380 1
415
620 3
4155 3
RIVERS
(KG/YR) (%)
31395 98
29740 73
2875 70
635 33
635 33
2500 59
280350 89
48030 61
89775 86
2790 It
14100 78
49575 67
135130 74
7595 83
18945 65
18010 62
8755 24
360 31
2185 45
135510 82
3850 40
485 34
3245 71
4410 95
1155 45
2320 52
30865 96
12795 61
106900 66
7755 65
23665 65
645 47
1990 80
1870 70
1680 93
DIRECT RUNOFF
(KG/YR) (%)
1960 5
825 20
870 46
870 46
1535 36
24940 8
9935 13
5480 5
295 1
2850 16
8445 11
9100 5
1365 15
1835 6
1820 6
1205 3
155 13
310 6
6690 4
715 7
780 54
1150 25
15
1275 50
1985 44
395 1
1155 6
4380 3
985 6
930 3
250 18
165 7
140 5
70 4
PRECIPITATION
(KG/YR) (%)
695 2
275 1
380 9
285 15
285 15
35 1
1840 1
495 1
200
20
100 1
1340 2
780
50 1
300 1
50
50
10 1
20
355
15
40 3
70 2
140 3
45 2
155 3
100
125 1
225
760 6
95
215 16
40 2
15 1
40 2
TOTAL
2
(KG/YR) (G/M /YR)
32100 .81
40750 2.58
4095 .19
1910 .12
1910 .12
4270 2.17
316630 3.01
79355 2.82
103845 9.15
24370 23.66
18035 3.15
74490 .97
183520 4.12
9100 3.04
29150 1.70
28880 10.20
36540 12.39
1155 2.18
4B75 4.03
164990 24.41
9730 11.18
1440 .61
4580 1.17
4625 .58
2570 .96
4485 .51
32005 5.65
20945 2.88
162465 12.74
11990 .28
36295 6.52
1370 .11
2475 1.04
2655 3.28
1805 .80
FLOW
(CMS) (M/YR)
10.34 8.193
15.66 31.257
10.19 14.877
.66 1.273
.66 1.273
.80 12.806
51.10 15.315
3.40 3.804
17.40 48.346
.60 18.370
1.80 9.924
9.20 3.793
19.60 13.884
.77 8. 1 ?i
4.50 8.284
5.10 56.832
1.60 17.104
.10 5.950
1.00 26.063
22.50 104.964
.10 3.625
.30 3.975
^.80 6.420
.10 .394
.40 4.724
.50 1.796
7.97 44.407
5.22 22.612
20.91 SI .719
10.96 7.946
5.40 30.574
.76 1.936
1.20 15.968
.46 17.909
.80 11.114
o
A45
-------
PHOSPHORUS LOADING
TETRA TECH..INC.
3700 MT. DIABLO BLVD.
LAP., CA. 94549
YEAR : 1972 TO 1975
TOTAL NUMBER OF LAKES : 493
STORET
NUMBER
1841
1842
1843
1844
1845
1846
1847
1851
1852
1853
1854
1855
1856
1857
1901
1902
1903
1907
1908
1909
1910
191 1
1912
1914
2001
2002
2003
2005
2006
2007
2008
2009
2010
2011
2012
MUNICIPAL i
(KG/VR) (X)
190 8
285 16
2560 23
1120 BO
1075 «2
k
9535 9
427160 IT
585 2
2410 6
64550 24
4865 5
970 9
310 1
14030 3
285 3
18455 18
3245 20
SEPTIC TANK
(KG/YR) (X)
20 1
15 1
40 3
50 1
10 1
15 6
115 24
50 6
85 6
10
55 5
10 2
25 1
10
5
15
,
INDUSTRIAL
(KG/YR) (X)
RIVERS
(KG/YR) (%)
1530 97
2005 88
650 56
3185 93
1400 80
290 85
130 54
545 71
1175 83
8060 74
1610 77
190 14
735 71
245 45
6365 82
1620 80
465 18
180 28
65175 60
2038205 82
5255 65
100 32
30 10
2850 64
12895 47
25740 65
246985 71
87765 92
4715 46
11610 53
396505 93
8000 72
75255 74
8925 56
DIRECT RUNOFF
(KG/YR) (X)
25 2
45 2
335 29
125 4
25 . 1
45 13
{.< 70 29
270 56
120 16
85 6
295 3
465 22
85 6
185 18
275 51
1375 18
325 16
980 38
440 69
33355 3'l
31730 1
2825 35
190 60
260 87
1095 25
13760 50
11230 28
17655 5
2725 3
4100 40
9675 44
16925 4
2685 24
7775 8
! 3420 22
PRECIPITATION
(KG/YR) (%)
C
15 1
130 11
55 2
20 1
5 1
25 10
100 21
55 7
75 5
5
5
5
55 5
10 2
60 1
65 3
65 3
15 2
780 1
635
45 1
25 8
10 3
485 11
230 1
310 1
665
250
435 4
490 2
1105
155 1
865 1
285 2
TOTAL
2
(KG/YR) (G/M /YR)
1580 4.39
2270 2.73
1 1 55 .15
3415 1.10
1740 1.53
340 .81
240 .16
485 .09
770 .24
1420 .34
10930 29.54
2080 8.32
1400 6.09
1030 .32
540 1.02
7800 2.27
2035 .55
2585 .67
635 .72
108855 2.45
2497730 68.96
8125 3.13
315 .24
300 .49
4435 .17
27470 2.07
39690 2.23
349855 9.20
95620 6.65
10220 .41
22085 .79
428565 6.54
11125 1.26
102350 2.07
15875 .98
FLOW
(CMS) (M/YR)
.90 78.840
.90 34.196
.30 1.255
2.74 27.784
1.00 27.663
.14 10.512
£ .25 5.256
.10 .554
.24 2.329
1.13 8.525
1.70 144.895
.76 95.869
.36 49.361
.36 3.493
.07 4.165
.99 9.076
.27 2.289
.41 3.367
.00 2.867
9.04 6.404
121.04 105.387
.57 6.914
.04 .978
.07 3.619
1 .70 1 .997
2.75 6.535
10.87 19.247
38.73 32.108
9.66 21.200
1.33 1.682
5.03 5.655
26.17 12.598
.62 2.207
12.71 8.119
4.66 9.077
A46
-------
YEAR : 1972 TO 1975
TOTAL NUMBER OF LAKES
493
PHOSPHORUS LOADING
TETRA TECH.,INC.
3700 MT. DIABLO BLVD.
LAP., CA. 94549
STORET
NUMBER
2014
2015
2101
2103
2203
2204
2205
2210
2211
2215
2217
2220
2304
2306
2308
2309
2310
2311
2312
2313
2314
2402
2403
2408
2409
2502
2503
2507
2508
2513
2603
2606
: 2609
: 2617
t 2618
MUNICIPAL
(KG/YR) (%)
12870 1
3795 22
19230 5
29310 27
28100 24
3175 IS
14275 27
1770 15
25140 31
3915 8
11235 74
4459 55
331 15
8264 70
290 10
145 3
3155 28
1630 19
12982 99
2445 63
62196 47
81356 65
25138 83
46996 23
1987 66
75858 94
1211 14
SEPTIC TANK
(KG/YR) (X)
20
155
460
30
5
105 1
70
5
20
30
14
299 11
136 1
145 7
517 6
86 1
209 7
41 3
255 9
5
5
:
: 36 1
100
t 231 3
1 141 52
INDUSTRIAL
(KG/YR) (X)
35 1
30
915 10
503 13
61235 46
:
RIVERS
(KG/YR) (X)
1380420 97
10920 64
354125 89
74625 68
79750 69
10750 62
32625 62
6295 52
43700 53
34660 73
2530 61
9100 62
3530 23
1561 57
3161 39
12184 49
939 43
5325 57
2614 22
822 27
1388 88
680 24
3425 73
7085 64
5760 66
63
853 22
7151 5
44294 35
4558 15
154152 76
766 25
4400 5
4187 49
35 13
DIRECT RUNOFF
(KG/YR) (%)
29895 2
1785 10
20835 5
5635 5
6545 6
2980 17
5995 1 1
3280 27
12070 15
8425 18
1320 32
5125 35
308 2
553 20
286 4
6990 28
327 15
1383 15
544 5
1247 42
91 6
1625 57
864 18
715 6
425 5
50
54 1
1220 1
113
476 2
286
200 7
490 1
1733 20
73 27
PRECIPITATION
(KG/YR) (X)
1 120
635 4
3560 1
21.0
1220 1
280 2
125
625 5
1080 1
220
300 7
430 3
27
345 13
236 3
5307 22
426 20
2037 22
304 "3
426 14
54 3
275 10
221 5
135 1
5
5
5
9
5
5
113
23 1
91
1220 14
23 8
TOTAL
2
(KG/YR) (G/M /YR)
1424305 22.28
17135 .47
397770 1.96
109935 9.24
116075 1.67
17215 1.07
53025 7.50
12075 .34
82060 1.33
47225 3.77
4170 .24
14685 .60
15114 9.65
2-758 . 1 4
8142 .60
24617 .08
2168 .09
9262 .08
11812 .68
2994 .12
1574 .51
2835 .18
4695 .37
11120 1.45
8740 20.81
13100 129.48
3860 10.84
131811 266.98
125768 817.84
30177 248.52
201547 31.40
3012 2.14
80939 15.75
8582 .12
272 .22
FLOW
(CMS) (M/YR)
52.86 26.071
3.40 3.022
252.84 39.209
16.73 44.468
40.81 18.473
6.94 13.628
8.90 40.056
6.15 5.422
51.82 26.512
5.17 13.002
4.14 7.639
11.24 14.362
5.02 100.835
5.50 8.804
13.71 32.074
52.90 5.505
- 3.8'J 5.053-
20.92 5.666
6.02 10.942
3.20 4.156
5.80 59.386
3.55 ' 7.095
4.60 11 .522
9.21 37.868
1.90 142.663
.07 22.075
1.63 142.788
8.85 569.579
6.79 1427.530
3.10 814.680
35.73 175.511
1.23 27.707
14.42 88.473
11.46 5.174
.08 2.018
A47
-------
PHOSPHORUS LOADING
TETRA TECH.,INC.
3700 MT. DIABLO BLVD.
LAP., CA. 94549
YEAR : 1972 TO 1975
TOTAL NUMBER OF LAKES : 493
STORET
NUMBER
2629
2631
2643
2648
2659
2673
2683
2685
2688
2691
2692
2694
2695
2696
2699
27A1
27A2
27A5
27A6
27A7
27B1
27B2
27B3
27B4
27CO
27C1
27C2
2702
2705
2709
2711
2712
2713
: 2715
: 2716
MUNICIPAL
(KG/YR) (X)
63484 92
4023 42
3461 54
25102 55
40569 35
3180 16
998 7
1973 10
2853 14
13082 84
2985 76
1034 21
1524 16
1247 97
13485 49
170055 83
1265725 49
34232 12
24503 94
844 41
1751 58
11866 48
1111 99
52263 63
399 87
7697 48
676 42
640 71
4822 56
! 6967 40
! 3139 36
SEPTIC TANK
(KG/YR) (X)
27
86
45
27
18
104 1
41
27 1
32 16
290 28
508 It
59 1
9 1
36
64
263
195 10
36
86 1
14
213 1
9 1
23
t 59 1
INDUSTRIAL
(KG/YR) (X)
662 3
395 1
23
•
RIVERS
(KG/YR) (%)
4962 7
4768 50
2739 43
19155 42
73543 64
12972 64
14007 92
17610 89
16566 80
1991 13
807 20
104 51
19 2
1415 29
7117 74
13703 50
34854 17
1266919 49
249788 85
503 2
558 27
1161 38
653 89
12351 50
10487 91
4
7928 13
6187 39
349 22
163 18
2884 34
11731 53
4803 56
DIRECT RUNOFF
(KG/YR) (%)
177
626 7
150 2
1243 3
721 1
4078 20
227 1
54
218 1
395 3
109 3
18 9
41 4
440 9
839 9
14 1
59
708
30000 1
10537 4
1030 4
59 3
59 2
9 1
191 1
449 4
5
1828 3
36 8
934 6
372 23
77 9
739 9
431 2
404 5
PRECIPITATION
(KG/YR) (X)
73
54 1
73 1
127
295
23
27
36
181 1
50
14
50 25
680 66
1420 29
18
14 1
73
27
417
581
1 13
381 19
64 2
68 9
109
454 4
5
172
23 5
894 6
195 12
14 2
109 1
1102 5
227 3
TOTAL
2
(KG/YR) (G/M /YR)
68696 16.17
9498 2.97
6423 1.59
45713 6.35
115173 6.86
20253 17.02
15286 9.24
19691 9.27
20584 1.98
15559 5.53
3942 4.62
204 .07
1030 .03
4817 .06
9557 9.19
1284 1.65
27356 6.43
205708 130.00
2563061 107.17
295401 8.89
26149 4.00
2037 .09
3035 .79
730 .19
24553 4.02
11476 .44
1125 4.96
62600 6.31
458 .37
15948 .31
1592 .14
903 1.22
8577 1.40
22231 .35
8632 .67
FLOW
(CMS) (M/YR)
14.09 104.551
.55 5.420
2.83 22.036
3.94 17.257
60.69 113.992
10.14 268.719
7.39 140.392
10.70 159.168
14.79 44.848
1 .74 19.528
1.64 60.846
.12 t.292
1.18 .958
4.44 1.726
6.16 186.790
.01 .404
11.45 84.962
8.56 109.291
287.00 378.485
144.22 136.909
.19 .916
1.20 1.730
1.06 8.751
.87 7.108
11.93 61.575
10.92 13.255
.01 1.371
1.60 5.335
.05 1.282
3.20 2.027
.30 1.080
.15 6.392
.63 3.252
17.76 8.875
1.55 3.795
A48
-------
PHOSPHORUS LOADING
TETRA TECH., INC.
3700 MT. DIABLO BLVD.
LAP., CA. 94549
YEAR : 1972*TO 1975
TOTAL NUMBER OF LAKES : 493
STORET
NUMBER
2719
2725
2737
2739
2746
2750
2756
2757
2761
2765
2776
2782
2783
2788
2793
2802
2804
2805
2606
2902
2903
2905
3001
3002
3003
3005
3007
3008
3009
3010
3011
: 3012
: 3013
: 3014
! 3016
MUNICIPAL
(KG/YR) (X)
1551 27
5352 98
14084 41
1751 10
1932 88
367 46
2930 69
358 14
156375 49
789 87
1533 89
3193 64
2204 88
9635 5
7000 2
4535 3
4830 3
7120 34
20700 42
1305
26290 15
135 1
4390 14
14775 11 :
:
SEPTIC TANK
(KG/YR) (X)
9
150 4
5
667 42
177 4
73 3
95 2
9
15
15
10
25
5
5
105
5
465
55
15 1
70 1
15
40 1
55
55 1
INDUSTRIAL
(KG/YR) (X)
45 3
RIVERS
(KG/YR) (X)
3761 66
63 1
2672 73
19011 55
6863 38
250 11
381 48
400 9
185 7
160266 50
176 10
1321 27
9
195735 94
421375 97
129020 92
145105 94
12140 58
11435 23
3770 44
323220 98
16930 85
137720 79
18410 76
645 58
8265 87
7295 96
2945 87
14865 88
2210 81
25115 78
100690 75
4505 77
DIRECT RUNOFF
(KG/YR) (X)
363 6
18
172 5
943 3
1424 8
812 51
9
32 4
227 5
1125 45
1715 1
86 9
14 1
181 4
150 6
2490 1
1700
4325 3
2525 2
940 5
15390 31
4450 52
2185 1
2655 13
655
4815 20
350 31
460 5
335 10
1855 11
425 16
1735 5
17815 13
1060 18
PRECIPITATION
(KG/YR) (%)
36 1
14
676 18
585 2
7924 44
77 5
9
14 2
503 12
776 31
172
32 4
5
186 4
132 5
920
2125
2195 2
1720 1
555 3
1765 4
310 4
2495 1
350 2
8325 5
895 4
110 10
570 6
325 4
60 2
190 1
95 3
885 3
250
235 4
TOTAL
2
(KG/YR) (G/M /YR)
5720 2.60
5447 7.87
3670 .10
34623 1.04
17967 .04
1601 .36
2200 5.38
794 1.20
4237 .15
25.17 .06
318528 32.54
907 .53
1728 5.08
4976 .47
2504 .33
208795 3. 98
432215 3.56
140075 1.12
154190 1.57
20780 .66
49295 .49
8535 .48
329310 2.31
19940 1.00
173455 .36
24175 .47
1 120 .18
9500 .29
7635 .41
3380 .97
16965 1.56
2730 .51
32125 .64
133530 9.44
5855 .43
FLOW
(CMS) (M/YR)
.47 6.737
.00 3.656
3.82 3.120
2.61 2.465
13.07 .909
.17 1.191
.25 19.229
.37 17.679
.43 .471
1.04 .741
67.86 218.594
.03 .553
.21 19.478
1.71 5.097
.21 .866
23.00 13.818
106.00 27.533
61.60 15.484
47.00 15.066
1 1 .07 11 .030
21.97 6.876
1.90 3.506
153.84 34.058
9.79 15.460
329. 6'J 21.861
28.33 17.426
.09 .462
14.77 14.275
1.90 3.248
5.82 52.590
32.39 94.143
4.25 24.959
28.17 17.560
12.83 28.594
5.57 12.954
A49
-------
PHOSPHORUS LOADING
YEAR : 1972 TO 1975
TOTAL NUMBER OF LAKES : 493
TETRA TECH..INC.
3700 MT. DIABLO BLVD.
LAF., CA. 94549
STORET
NUMBER
3101
3102
3103
3104
3105
3106
3107
3110
3201
3202
3204
3206
3302
3303
3305
3306
3402
3403
3406
3409
3410
3412
3415
3419
3420
3423
3501
3502
3503
3505
3506
3507
: 3509
: 3604
! 3605
MUNICIPAL
(KG/YR) (X)
3190 3
1320 3
1475 1
1560 9
322055 9
2540 52
10006 45
3230 21
4032 50
325 13
1065 54
11315 28
19590 B6
345 27
5495 47
40 3
365 10
2625 9
540360 21
1375 4
13610 56
2481 41
SEPTIC TANK
(KG/YR.) (X)
45
5
10
165
45
10
10
5
5
1710 8
64
36
5 1
475 20
20 1
5
1
320 25
10
1
20
40
5
5
299 5
I
INDUSTRIAL
(KG/YR) (X)
RIVERS
(KG/YR) (X)
3335 64
113150 93
36935 B1
6515 61
77095 100
174085 90
1575 72
15105 86
3166635 86
162435 87
52995 97
12825 97
2010 41
5198 23
11662 78
3878 48
85 19
990 41
11930 89
850 43
28275 71
3205 14
140 1 1
5865 50
1135 78
2450 65
24605 88
330 56
9340 .82
2025840 79
32230 92
10040 41
10010 89
1402 23
81494 98
DIRECT RUNOFF
(KG/YR) (X)
1790 34
3785 3
7490 16
3955 37
14325 7
565 26
470 3
193760 5
24840 13
695 1
185 1
307 6
2250 10
77 1
73 1
330 74
510 21
1445 11
35 2
135
70
295 23
250 2
190 13
765 20
485 2
135 23
1390 12
475
1080 3
180 1
920 8
1107 18
962 1
PRECIPITATION
(KG/YR) (X)
125 2
955 1
130
115 1
200
2480 1
50 2
350 2
10375
345
B05 1
170 1
27 1
3157 14
9
5
25 6
135 6
45
10 1
15
5
190 15
10
90 6
165 4
325 1
125 21
680 6
2590
230 1
405 2
295 3
753 12
340
TOTAL
2
(KG/YR) (G/M /YR)
5250 .72
121125 2.22
45880 6.13
10595 1.61
77460 6.72
192410 1.36
2190 .73
17495 .87
3692835 6.23
187625 ' 9.53
54495 1.18
13180 1.36
4889 3.24
22321 .12
15042 28.92
8024 13.13
445 .29
2435 .31
13420 5.08
1980 3.47
39745 47.89
22871 60.19
1290 .12
11630 18.17
1456 .28
3745 .40
28060 1.52
590 .08
11450 .29
2569270 17.35
34920 2.67
24235 1.05
11225 .67
6042 .14
82796 4.26
FLOW
(CMS) (M/YR)
.46 1.993
9.93 5.746
1.96 8.252
1.06 5.073
29.65 81.096
37.26 8.296
.12 1 .266
3.42 5.358
314.74 16.741
16.62 26.619
5.80 3.964
6.77 21.988.
6.69 139.719
18.25 3. 190
8.92 540.964
8.26 427.028
.22 4.564
1.35 5.479
1.66 19.829
.37 20.471
7.83 297.502
3.50 290.463
1.11 3.220
3.03 149.303
1.61 9.727
1.17 3.946
2.77 4.724
.26 1.160
4.70 3.882
38.31 8.160
8.53 20.582
6.94 9.495
3.14 5.898
3.63 2.663
20.56 33.387
A50
-------
PHOSPHORUS LOADING
TETRA TECH.,INC.
3700 MT. DIABLO BLVD.
LAP., CA. 94549
YEAR : 1972 TO 1975
TOTAL NUMBER OF LAKES : 493
STORE!
NUMBER
3606
360B
361 1
3617
3632
3633
3635
3637
3639
3640
3641
3701
3702
3704
3705
3706
3707
3711
3713
3715
3716
3717
37 IB
3719
3B01
3804
3807
3808
3812
3814
3901
3902
3905
: 3906
: 3907
MUNICIPAL
(KG/YR) (X)
370B1 44
59057 20
567 3
13209 51
45450 6B
19713 80
95 12
39690 25
1 155
22020 2
6245 5
11015 11
298345 31
4415 10
8765 9
41140 20
1235 16
1555
23470 18
1975 6
17655
3990 9
1580 24
17380 57
10515 37
13850 21
SEPTIC TANK
(KG/YH) (X)
5
336
45
744 15
150 1
86
3035 5
27
336 7
9 1
10
55
25
25
200
65
125 6
35
10
10 1
560 1
235 4
50
t 120
INDUSTRIAL
(KG/YR) (X)
2750 2
RIVERS
(KG/YR) (X)
15862 85
37508 45
234653 79
1642 33
16130 74
11975 46
10927 16
3929 16
3347 68
145 19
114820 71
399785 99
920660 98
103830 84
B6710 86
643250 68
37455 83
55400 98
81130 85
158595 78
6150 78
312910 99
100025 78
1270 58
28340 88
17380 91
2505 93
600 75
6480650 97
1275 68
3B210 83
3990 61
11915 39
16835 59
44865 68
DIRECT RUNOFF
(KG/YR) (X)
2318 12
6169 7
1365
1724 35
2898 13
535 2
4536 7
816 3
1016 21
481 63
3540 2
1245
675
13320 11
3050 3
7355 1
3030 7
765 1
3595 4
2450 1
275 3
2700 1
5230 4
145 7
1300 4
1010 5
150 6
190 24
173370 3
580 31
3365 7
465 7
910 3
1195 4
6750 10
PRECIPITATION
(KG/YR) (%)
458 2
3007 4
154
830 17
2132 10
286 1
3066 5
59
227 5
32 4
855 1
425
180
755 1
290
1 125
445 1
230
2300 2
250
205 3
375
25
635 29
385 1
700 4
35 1
10 1
26080
20 1
30
220 3
95
90
90
TOTAL
2
(KG/YR) (G/M /YR)
18643 .71
84101 .49
295274 33.53
4940 .10
21877 .18
26091 1 .60
67014 .38
24544 7.07
4926 .38
762 -41
161665 3.31
402665 16.66
943535 91.07
124175 2.88
101065 6.08
950075 14.78
45370 1.79
56395 4.31
95990 .73
202435 14.24
7865 .68
317605 14.92
128750 93.30
2175 .06
32035 1.46
19090 .48
2690 1.35
800 1.51
6697765 4.49
1885 1.71
46155 27.15
6490 .51
• 30350 5.56
28635 5.54
65675 12.49
FLOW
(CMS) (M//R)
42.86 51.727
26.43 4. 847
85.36 305.552
4.32 2.874
64.73 16.732
9.97 19.266
14.61 2.628
5.87 53.348
2.17 5.309
1.00 16.864
105.60 68.284
141.40 184.493
213.60 650.202
115.50 84.354
55.90 106.005
136.60 67.006
54.00 67.019
67.20 161.896
65.20 15.628
48.44 107.426
14.00 38.094
154.60 229.003
24.10 550.737
2.60 2.267
3.35 4.806
3.15 2.480
.17 2.681
.11 6.545
566.84 1 1 .996
.20 5.734
7.20 133.564
1.20 2.977
5.40 31.189
7.20 43.919
8.70 52.160
A51
-------
YEAR : 1972 TO 1975
TOTAL NUMBER OF LAKES
493
PHOSPHORUS LOADING
TETRA TECH..INC.
3700 MT. DIABLO BLVD.
LAP., CA. 94549
STORET
NUMBER
3908
3912
3914
3921
3924
3927
3928
3929
3930
3931
3932
4001
4002
4003
4004
4005
4006
4008
4009
4010
401 1
4012
4013
4014
4101
4104
4106
4107
4201
4204
4207
4213
4216
4219
! 4220
MUNICIPAL
(KG/YR) (%)
71770 41
1480 23
5425 27
3625 36
8580 71
1445 7
2525 24
34990 67
6250 82
57755 24
5305 32
1980 36
429755 25
260 3
980 30
595 1
34600 3
22765 1
8330 2
16970 16
5315
64840 96
11885 28
3215 21
19295 34
610 B
:
SEPTIC TANK
(KG/YR) (X)
30
50
275 1
55 1
180
35
195
5
5
10
5
5
60
10
15
20
5
10 1
60
5
15
: 5
i 5
t
INDUSTRIAL
(KG/YR) (X)
75
12585 1
13610 32
1975 3
:
RIVERS
(KG/YR) (X)
102105 58
4285 66
12210 61
2210 22
2935 24
16085 74
6875 66
12090 23
1035 14
178050 75
8985 54
9810 92
2135 56
1570 29
1175940 68
5965 64
2050 62
75645 89
1231685 95
4250 94
1705265 97
390670 95
77480 71
5750 73
1885410 99
33155 82
1032285 99
1520 82
2355 3
755 39
14365 34
5250 34
34605 61
6350 82
1630 77
DIRECT RUNOFF
(KG/YR) (%)
2345 1
685 11
1985 10
3600 36
490 4
3085 14
815 8
4850 9
315 4
880
2345 14
445 4
1510 40
1545 28
113940 7
2850 30
150 5
8500 10
15625 1
110 2
23945 1
10360 3
13685 13
1695 22
4550
7190 18
6260 1
305 16
255
1105 57
2290 5
5870 38
420 1
710 9
410 19
PRECIPITATION
(KG/YR) (%)
95
15
200 1
550 6
60
780 4
110 1
155
15
60
145 1
445 4
165 4
395 7
7260
290 3
135 4
40
3295
175 4
1860
2085 1
895 1
430 5
990
195
100
20 1
125
65 3
60
1165 B
250
80 1
65 3
TOTAL
2
(KG/YR) (G/M /YR)
176420 32.91
6465 8.51
19870 1 .74
9985 .32
12065 3.51
21670 .49
10380 1.67
52265 5. 87
7650 8.41
236940 70.73
16780 2.05
10705 .42
3810 .40
5495 .24
1726905 4.16
9370 .57
3320 .44
84780 36.70
1297850 6.90
4535 .45
1753845 16.48
411460 3.45
109050 2.13
7880 .32
1896265 33.47
40540 3.66
1038645 183.51
1855 1.70
67635 9.66
1925 .51
42215 12.83
15515 .23
56550 3.92
7755 1.70
2105 .55
FLOW
(CMS) (M/YR)
20.70 121.790
.70 29.046
4.90 13.519
2.40 2.397
5.10 46.754
5.40 3.825
2.00 10.124
6.20 21.969
.40 13.862
21 .50 202.395
3.40 13.124
2.48 3.078
.80 2.918
2.63 3.660
156.96 11.933
.44 .842
1 .80 7 .459
14. 8H 203.141
183.86 30.812
.9'J 3.085
1 73.80 51 .498
72.21 19.101
38.32 23.607
.32 .411
526.27 292.913
33.04 94.124
532.66 2967.838
1.44 41.662
12.00 54.062
3.00 25.029
3.80 36.425
5.60 2.658
20.00 43.770
3.50 24.258
4.10 33.759
A52
-------
PHOSPHORUS LOADING
YEAR : 1972 TO 1975
TOTAL NUMBER OF LAKES
493
TETRA TECH.,INC.
3700 MT. DIABLO BLVD.
LAP., CA. 94549
STORET
NUMBER
4221
4222
4223
4224
4225
4226
4227
4229
4402
4403
4503
4504
4505
4506
4507
4508
451 1
4513
4515
4602
4603
4610
4620
4624
4626
4627
4629
4704
4707
4708
4711
4712
4713
: 4717
i 4722
MUNICIPAL •
(KG/YR) (X) !
15 3
25 8
30 5
3620 17
1055 37
620 7
757 16
30137 37
538500 74
345640 86
57950 31
711285 45
178375 60
925 28
175855 40
1475 7
1330 13
3060 14
95130 50
34705 7
60155 5
12870 2
402170 40
20310 14
378470 22
74930 6
SEPTIC TANK
(KG/YR) (X)
140 26
115 16
60 18
15 3
30
15 1
245 3
18
1540 1
1900
1425
25 1
30
-
'
5
25 1
30 8
5 2
5 1
120
30
: 45
! 75
i 170
! 20
t 60
t 75
INDUSTRIAL
(KG/YR) (X)
45358 56
25860 14
!
RIVERS
(KG/YR) (X)
340 63
260 36
40 12
355 63
15870 76
295 55
1255 45
6055 73
3833 82
4435 6
182500 25
47555 12
80370 43
845040 53
102740 35
1805 55
264025 59
17540 81
34150 100 '
615 98
8560 83
260 81
3655 89
160 43
15985 73
220 75
525 80
94925 50
423635 90
1232255 94
663500 97
587475 59
118755 84
1355075 78
1218245 93
DIRECT RUNOFF
(KG/YR) (X)
35 6
295 41
150 45
125 22
1360 6
215 40
440 16
1000 12
77 2
553 1
2070
6750 2
17645 9
16750 1
10965 4
400 12
4115 1
1395 6
85
45
30 9
345 8
125 33
2815 13
45 15
90 14
475
9285 2
1 1 395 1
3770 1
10775 1
1285 1
1445
14220 1
PRECIPITATION
(KG/YR) (X)
10 2
45 6
55 17
35 6
75
25 5
55 2
410 5
14
IB
240
805
4350 2
7835
3600 1
150 5
930
1215 6
40
10 2
340 3
30 9
60 1
60 16
55
25 8
40 6 .
310
2145
2505
2155
1035
215
735
2760
TOTAL
2 •
(KG/YR) (G/M /YR)
540 . .78
715 .27
330 .11
560 .28
20955 4.78
535 .39
2820 .93
8330 .36
4699 5.61
80501 77.40
723310 53.03
400750 8.69
187715 .83
1582810 3.54
297105 1.45
3305 .38
444955 8.38
21625 .31
34275 15.23
625 1.42
10280 .53
320 .19
4085 1.17
-375 .11
21915 7.07
295 . 1 9
660 .30
190960 10.73
469800 3.83
1306355 9.12
682370 5.55
1001625 16.95
140585 11.36
1735785 41.36
1310230 8.30
FLOW
(CMS) (M/YR)
.80 36.563
.60 7.087
.50 5.187
1.00 15.612
12.00 86.400
.60 13.711
3.50 36.308
10.00 13.529
4.43 166.315
2.64 80.053
133.07 307.661
49.50 33.833
119.76 16.680
469.85 33.104
B6.66 13.294
6.53 23.725
110.19 65.442
31 .52 . 14.321
17.60 247.803
.06 4.300
3l83 6.259
.20 5.256
1.10 9.968
.01 .094
2.36 24.008
.14 2.830
.09 1.273
65.85 116.665
115.90 29.828.
927.75 204.241
182.27 46.721
371.59 198.315
84.45 215.122
957.05 719.121
741.05 148.079
A53
-------
YEAR : 1972 TO 1975
TOTAL NUMBER OF LAKES : 493
PHOSPHORUS LOADING
TETRA TECH..INC.
3700 MT. DIABLO BLVD.
LAP., CA. 94549
STORET
NUMBER
4723
4724
4725
4728
4801
4802
4B03
4805
4806
4808
4809
4810
4811
4812
4813
4814
4815
4816
4817
4818
4819
4820
4821
4822
4823
4824
4825
4826
4827
4828
4829
4830
4831
4832
: 4834
MUNICIPAL
(KG/YR) (X)
72720 27
29730 54
22030 41
4965 30
24210 12
35
8500 4
1755 3
34060 29
145255 49
18930 26
27260 31
42240 2
16445 46
1135 39
123605 29
45830 66
8930 4
28525 20
3760 15
9225 34
6350 66
32175 24
38495 3
SEPTIC TANK
(KG/YR) (X)
30
20
10
5
50
170 2
325
20
115 8
200
40 1
165
125 3
215 2
95
80
30
465 1
125 4
255
35
5
50
:
225
INDUSTRIAL
(KG/YR) (X)
825
RIVERS
(KG/YR) (X)
190490 70
23125 42
29755 55
7550 46
244B95 95
BBS 90
162935 82
6455 76
B9045 97
9980 95
4010 78
1020 73
195250 92
3865 84
48560 88
1 980 49
64670 55
10190 83
146680 49
39505 55
57815 65
2092505 97
18260 51
955 33
303040 71
13595 20
201250 93
880 63
93390 67
13330 94
14555 58
16145 59
2380 25
82655 61
1414575 96
DIRECT RUNOFF
(KG/YR) (X)
7745 3
1025 2
1660 3
3560 22
7805 3
35 4
10595 5
1375 16
830 1
325 3
505 10
140 10
7455 4
435 9
4005 7
1730 43
16725 14
745 6
3815 1
11835 17
2765 3
7935
365 1
275 10
140 -
8420 12
4830 2
175 13
10100 7
340 2
4965 20
1670 6
400 4
17275 13
18815 1
PRECIPITATION
(KG/YR) (%)
1005
750 1
535 1
280 2
4595 2
65 7
870
515 6
1635 2
245 2
585 11
1 15 8
1550 1
240 5
635 1
190 5
1650 ' 1
1090 9
865
1315 2
785 1
5850
450 1
395 14
1170
1810 3
1400 1
340 24
8005 6
450 3
1730 7
335 1
455 5
2600 2
6305
TOTAL
2
(KG/YR) (G/M /YR)
272815 4.75
54650 1.27
53990 • 1 .76
1636t) 1.02
257295 .98
985 .27
198660 3.95
8515 .29
91870 .98
10550 .76
5120 .15
1390 .21
212955 2.40
4580 .33
55120 1.51
4025 .37
117105 1.25
12240 .20
296615 5.99
71680 .95
88705 1.03
2148560 6.43
35985 1.39
2885 .13
427955 6.41
69655 .67
216665 2.70
1395 .06
140055 .30
14120 .55
25015 .54
27425 1.44
9585 .37
134705 .91
1478415 4.10
FLOW
(CMS) (M/YR)
40. 53 22.268
22.89 16.827
25.32 26.026
12.40 24.430
36.18 4.347
.13 1.117
17.11 10.734
3.64 3.886
23.07 7.796
.12 .271
7.91 7.480
.32 1.548
24.57 8.742
3.79 8.636
7.45 6.451
.87 2.510
17.51 5.879
3.7t 1.882
38.02 24.208
16.14 6.762
10.84 3.955
191 .55 18.071
35.82 43.784
3.67 5.130
3.95 1 .866
12.00 3.683
28.24 11.114
.54 .779
42.30 2.884
.76 .935
6.5'j 4.481
.85 1.411
6.97 8.448
11.26 2.391
137.00 11.995
A54
-------
YEAR : 1972 TO 1975
TOTAL NUMBER OF LAKES
493
PHOSPHORUS LOADING
TETRA TECH..INC.
3700 MT. DIABLO BLVD.
LAP., CA. 94549
STORET
NUMBER
4835
4S37
4838
4839
4901
4903
4904
4906
4908
4909
4910
4913
4914
4915
4917
4920
4921
4923
4924
4925
5001
5002
5005
5007
500B
5010
501 1
5103
5105
5106
5108
5110
5111
: 5112
: 5113
MUNICIPAL
(KG/YR) (X)
2325 5
11170 9
7360 31
3785 25
1020 IB
2885 9
125700 62
1 10 1
152098 14
875 19
2041 26
4554 29
19999 42
7416 20
1905 39
34730 19
3075 27
275270 33
23665 25
87105 48
7480 15
6825 35
230 1
SEPTIC TANK
(KG/YR)" (X)
15
15 3
250
95 1
40 B
20 1
14
259 3
172
5
145
135
5
75
5
20
INDUSTRIAL
(KG/YR) (X)
4195 18
2435 42
7645 4
3801 10
5475 3
1725 B
RIVERS
(KG/YR) (%)
44305 90
705 45
305 66
103570 88
11000 75
11715 49
10085 68
180 36
3135 94
1940 33
1530 94
6115 95
1635 90
775 85
19895 96
28810 86
26465 88
275 93
52290 26
7540 90
484817 46
3665 78
4205 54
10891 70
20974 44
26100 69
2022 42
146415 80
6840 60
521375 63
68795 73
74565 41
40095 80
11595 60
19060 89
DIRECT RUNOFF
(KG/YR) (%)
1415 3
205 13
10 2
1220 1
640 4
410 2
925 6
100 20
115 3
350 6
45 3
120 2
75 4
20 2
580 3
945 3
3515 12
5 2
9320 5
419657 40
150 3
1134 15
154 1
4926 10
254 1
835 17
1450 1
1455 13
21600 3
1125 1
11725 7
2585 5
925 5
480 2
PRECIPITATION
(KG/YR) (%)
1340 3
640 41
130 28
1670 1
3005 20
170 1
105 1
175 35
85 3
70 1
55 3
180 3
85 5
120 13
180 1
780 2
195 1
15 5
6940 3
. 710 8
9
154 2
9
1656 3
59
64 1
320
80 1
3470
120
1415 1
225
105 1
30 .
TOTAL
2 ,
(KG/YR) (G/M /YR)
49400 .64
1550 .04
460 .06
117880 1.24
14740 .09
23850 2.47
14900 2.50
495 .05
3335 .70
5815 1.45
1630 .52
6415 .63
1815 .36
915 .13
20655 2.03
33420 .75
30175 2.70
295 .40
201895 .51
8360 .21
1056572 .93
4713 8.32.
7793 .88
15608 25.21
47727 .50
37635 11.26
4826 1.34
183060 10.06
11450 2.47
821850 4.15
93710 13:62
G1 80360 2.23
50390 3.89
19470 3.21
21525 11.83
FLOW
(CMS) (M/YR)
45.02 18.532
.49 .423
.12 .517
45.80 15.178
2.53 .465
10.54 34.409
7.86 41.659
.14 .436
2.82 18.762
.98 7.707
3.65 36.893
1 .44 4.452
.47 2.970
.02 .092
4.92 15.286
5.61 3.974
3.47 9.797
.45 19.440
10.62 .844
2.34 1.823
312.96 8.732
6.04 334.171
13.63 48.624
12.37 629.194
27.27 9.094
34.43 325.085
6.30 55.889
97.50 169.036
8.20 55.852
197.80 31 .464
14.50 66.464
28.30 11.026
34.10 83.041
7.90 41.044
7.80 135.154
A55
-------
YEAR : 1972 TO 1975
TOTAL NUMBER OF LAKES
493
PHOSPHORUS LOADING
TETRA TECH.,INC.
3700 MT. DIABLO BLVD.
LAP., CA. 94549
STORET
NUMBER
5306
5309
5311
5312
5401
5402
5403
5404
5509
5513
5519
5520
5522
5531
5538
5539
5541
5546
5548
5550
5555
5556
5559
5564
5565
5570
5574
5601
5602
5603
5605
5606
5607
: 5608
: 5609
MUNICIPAL
(KG/YR) (X)
9905 32
105310 40
85
4440 14
5330 11
894 34
6064 76
3352 45
544 3
66954 16
3134 57
1973 1
6495 11
1 102 1
454 54
735 22
20625 4
3461 2
7864B 84
1452 3
1651 20
t8750 6
40405 22
2680 2
: 1270 7
: 70 1
SEPTIC TANK
(KG/YR) (X)
20
110 2
75 3
20
35
15
73 3
172 2
209 3
122 1
113
168 3
77
113 6
59
59
27 3
77 2
191
204
159
27
14
23
S
15 1
! 5'
s
t
INDUSTRIAL
(KG/YR) (X)
2B25 1
RIVERS
(KG/YR) (%)
1810 40
19680 63
4780 78
540 21
153615 58
59795 99
24860 80
32135 67
1178 45
667 8
1410 19
18013 88
348016 83
1769 32
238684 97
727 40
49788 84
135246 97
317 37
1969 58
521926 95
187009 96
14401 15
38207 91
6078 75
7530 78
7160 72
3595 75
287630 90
130890 70
1440 61
171200 98
13920 79
5905 90
DIRECT RUNOFF
(KG/YR) (%)
2535 56
1055 3
895 15
1620 63
2470 1
535 1
1530 5
10490 22
386 15
980 12
1932 26
1510 7
2740 1
372 7
5416 2
535 30
2640 4
2499 2
41 5
553 16
4599 1
3688 2
762 1
141 64
1769 4
358 4
1755 18
2675 27
1080 22
12070 4
12535 7
550 23
125
1745 10
i 130 2
PRECIPITATION
(KG/YR) (%)
180 4
485 2
345 6
355 14
145
125
195 1
125
73 3
127 2
522 7
191 1
739
73 1
776
435 24
163
122
9 1
82 2
630
445
82
82 37
485 1
18
363 4
145 1
125 3
1570
2410 1
355 15
945 1
665 4
430 7
TOTAL
2
(KG/YR) (G/M /YR)
4525 .44
31145 1.13
6130 .31
2590 .13
264385 32.05
60575 8.65
31025 2.82
48095 6.79
2604 .64
B010 1.12
7425 .25
20380 1.85
418562 9.87
5516 1.33
246926 5.55
1810 .07
59145 6.35
139028 20.30
848 1.40
3416 .71
547971 15.21
194807 8.87
94052 20.51
222 .05
41940 . 1.52
8119 8.57
9671 .47
9980 1.20
4805 .68
320020 3.56
186240 1.35
2360 .12
174955 3.24
17600 .46
6535 .26
FLOW
(CMS) (M/YR)
10. in 30.988
6. 40 7.409
6.37 10.135
4.50 7.008
159.90 611 .225
88.40 398.255
53.50 153.101
72.70 323.823
1.37 10.615
.62 2.723
1.42 1.506
4.85 13.917
33.82 25.148
.85 6.459
84.15 59.662
1 .67 2.114
4.64 15.717
31 .98 147.229
.10 5.170
1.51 9.921
207.09 181.310
133.06 190.996
5.39 37.032
.23 1.543
9.66 11.022
1 . 16 38.507
9.21 13.977
2.05 7.752
5.47 24.538
40.00 14.04*1
63.18 14.473
6.30 9.821
43.34 25.325
.51 .423
.75 .958
A56
-------
PHOSPHORUS LOADING
TETRA TECH..INC.
3700 MT. DIABLO BLVD.
LAP., CA. 94549
YEAR : 1972 TO 1975
TOTAL NUMBER OF LAKES
493
STORET
NUMBER
5610
5613
5614
N
MEAN
S.D.
MAX.
STR.NO
MIN.
STR.NO
MUNICIPAL
(KG/YR) (X)
4205 3
6685 16
6055 1
356
36779.45
10B261 .07
1265725
27A6
C
0625
SEPTIC TANK
(KG/YR) (X)
332
110.22
263.99
3035
3635
1
1010
INDUSTRIAL
(KG/YR) (%)
2125
32
9765.22
22458.48
108130
1601
20
1725
RIVERS
(KG/YR) (%)
122185 86
34480 81
1018325 97
487
127903.98
435151 .00
6480650
3812
4
27C2
DIRECT RUNOFF
(KG/YR) (%)
14455 10
1365 3
20820 2
488
5218.55
23327.48
419657
5001
g
0804
PRECIPITATION
(KG/YR) (%)
855 1
125
900
492
734.47
1723.81
26080
3812
5
0404
TOTAL
fy
(KG/YR) (G/M /YR)
141700 2.91
42655 6.02
1048225 20.42
493 493
159513. 10.64
486648. 44.91
6697765 817.84
3812 2508
204 .03
2694 2695
FLOW
(CMS) (M/YR)
42.20 27.339
6.87 30.601
100.70 61.905
493 493
41.21 71.213
110.49 201.678
1153. 16 2967.838
0104 4106
.01 .092
27A1 4915
N • NUMBER OF LAKES WITH NON-ZERO DATA
A57
-------
PHOSPHORUS LOADING
TETRA TECH.,INC.
3700 MT. DIABLO BLVD.
LAP., CA. 94549
YEAR : 1972 TO 1975
TOTAL NUMBER OF LAKES
493
STATISTIC FOR X CALCULATION
STORET
NUMBER
N
MEAN
S.D.
MAX.
STR.NO
MIN.
STR.NO
MUNICIPAL
(KG/YR) (X)
347
29. 12
25.54
99
2502
1
0409
SEPTIC TANK
(KG/YR) (X)
114
5. OB
7.98
52
2618
1
! 0409
INDUSTRIAL
(KG/YR) (X)
24
12.31
15.92
56
4403
1
1739
RIVERS
(KG/YR) (X)
484
64. 16
25.56
100
3105
1
2725
DIRECT RUNOFF
(KG/YR) (X)
452
12.21
14.30
87
1914
1
0101
PRECIPITATION
(KG/YR) (%)
321
5.22
7.60
66
2695
0107
TOTAL
2
(KG/YR) (G/M /YR)
FLOW
(CMS) (M/YR)
A58
-------
COMPUTED PARAMETERS 1972-1975
-------
YEAR : 1972 TO 1975
TOTAL NUMBER OF LAKES
493
TETRA TECH..INC.
3700 MT. DIABLO BLVD.
LAF., CAL. 94549
STORET
CODE
0101
0104
0105
0107
01 12
01 15
0403
0404
0405
0406
0408
0410
041 1
0501
0502
0504
0505
0506
0507
0508
0510
0514
0515
0516
0601
0602
0606
0608
061 1
0614
0616
0620
0621
0624
0625
TIME-
DEPTH
1 1
1 1
1 2
1 2
1 1
1 2
1 2
1 1
3 2
1 2
1 1
3 3
3 2
3 2
1 1
1 3
1 2
1 1
1 2
1 1
1 2
3 2
1 2
1 3
1 2
1 2
3 3
1 1
1 3
4 2
1 2
3 2
1 3
1 2
1 2
0626 : 1 2
: 0801 : 1 2
TROPHIC
STATE
: 0803 : 1 3 :
E
E
E
M
E
E
M
E
p
M
E
M
E
M
HE
M
E
p
M
E
E
M
M
M
E
0
M
0
E
C
MU
E
M
c
WPN
226
228
226
231
235
234
728
729
730
731
734
735
736
480
481
480
483
484
485
486
483
483
480
487
739
740
744
746
749
750
752
756
757
760
M : 762
M : 761
M : 765
M I 767
K1
6.99
5.36
7.56
1 .44
4.82
1 .83
3.40
1 .83
.65
2.24
1 .46
.73
.58
.81
6.78
1 .19
6.93
2.74
.87
2.36
2.89
.73
1.05
.67
1.18
1 .80
.77
2.36
5.69
.37
1.47
.80
1 .30
4.40
1.64
1.52
1.8S
1.15
K2
96.44
2.34
29.63
3.38
14.77
4.98
5.56
. 19
.77
1 .22
2.24
2.45
16. 12
2.24
9.98
.83
28.74
1 .74
. 1 1
2.82
9.27
. 11
3.21
.41
1 .56
.86
.63
1 .36
2.58
.07
1 .36
.41
.25
2.90
1.22
.47
.60
2.B7
K1*Z
21.66
24.66
59.74
18.58
13.51
9.34
31.28
4.59
4.36
42.33
6.73
20.33
8.92
14.43
12.20
24.24
38. 14
7.41
13.03
4.96
28.07
11.96
20.10
14.28
20.55
23.06
36.66
3.54
121.77
6.10
28.12
8.07
60.23
72.55
23.41
23.15
K2*Z
298.95
10.74
234. 10
43.61
41 .35
25.42
51.11
.47
5.17
23.10
10.29
68.69
246.62
39.92
17.96
16.99
158.07
4.70
1.64
5.92
89.89
1.73
61.29
8.76
27.16
10.95
30.01
2.04
55.20
1 .14
25.93
4.17
1 1 .80
47.84
17.44
7.10
15.60 : 4.94
35.72 : 89.24
ALPHA
1 .260
1 .440
1 . 190
.820
2.460
.750
.730
.550
3.970
.400
.740
.810
2.000
.690
15.690
.400
1 .060
3.750
.520
1 .070
.680
.490
.520
.410
.250
.470
.460
. 120
.950
.310
.940
.460
.450
.670
.250
R(M)
.664
.075
.341
.620
.388
.598
.325
.0.53
.646
.196
.511
.823
.979
.773
.178
.371
.374
.188
.126
.336
.525
.165
.743
.479
.528
.209
.516
.197
.074
.337
.385
.393
.131
.130
.313
.190 : .168
.660 : .144
.460 : .685
R(C)
.130
.160
. 120
.410
.170
.350
.230
.350
.610
.310
.410
.580
.630
.550
.130
.460
. 130
.270
.530
.300
.260
.580
.490
.600
.460
.360
.570
.300
.150
.730
.400
.560
.440
. 190
.380
.400
.350
.470
AGO
-------
YEAR : 1972 TO 1975
TOTAL NUMBER OF LAKES
493
TETRA TECH.,INC.
3700 MT. DIABLO BLVD.
LAP., CAL. 94549
: STORET
: CODE
: 0804
: 0606
: OB07
: OBOB
: 0812
: 0901
! 0904
! 0905
: 0910
: 091 1
: 0912
t 1005
! 1007
1 1008
< 1009
: 1010
: 1301
: 1302
: 1303
: 1304
: 1309
: 1310
: 131 1
: 1313
: 1316
: 1317
: 1318
: 1319
: 1601
: 1602
: 1603
: 1604
: 1608
1 609
: 161 1
: 1612
TIME-
DEPTH
4 2
3 3
1 3
1 3
3 3
1 1
1
1
1 2
1 2
1
t
1
1
1
1
1 2
1 2
1 2
1 2
1 2
3 2
1 2
1 2
1 2
1 2
1 2
1 1
1 2
1 2
4 1
1 3
1 2
1 2
1 2
3 1
: 1613 : 3 1
TROPHIC
STATE
'
J 1703 tilt.
E
0
M
0
MU
E
E
HE
E
E
E
E
E
c
E
E
c
p
M
ME
E
M
M
p
LM
E
LM
E
E
E
M
o
E
E
M
E
c
WPN
768
769
770
771
775
. 176
179
180
181
181
181
238
239
240
242
241
281
283
286
287
290
293
291
294
284
282
285
289
776
777
778
779
783
785
784
7B7
787
E : 296
Kl
.53
.88
2.22
1.49
.86
17.70
23.79
20.71
8.65
4.66
24.40
15.05
4.34
6.80
10.87
7.96
1 .88
4.85
1.11
1.64
3.43
.78
1 .26
2.62
1.44
5.13
1.51
5.13
1.66
1.04
4.32
1.09
1.18
1.44
1.62
.74
.74
K2
1 .58
1.91
3.67
.07
3.45
22.78
151 .33
.82
24.51
22.02
112.06
57.93
15.27
43. 13
3.57
33.17
6.46
15.72
.51
4.40
20.06
5.09
1 .00
3. 15
1.17
30. 12
2.77
B.27
. 16
.60
11.99
.45
1 .06
2.96
.04
3.95
3.95
1.60 : 1.17
K1*2
2.76
21.54
91.82
33.10
28.66
46.89
21 .64
28.38
64.85
55.22
70.03
16.55
4.77
10.20
13.05
9.55
17.68
25.70
11.77
17.91
23.70
15. 18
16.47
17.29
26.53
48.24
17.91
18.98
15.26
8.40
9.94
60.67
6.95
21.65
9.21
1.71
1.71
8.00
K2*Z
8.23
47.00
151 .57
1.51
1 14.72
60.37
137.71
1 .12
183.84
261 .13
321.61
63.73
16.80
64.70
4.28
39.81
60.70
83.30
5.43
48.01
138.41
99.23
13.10
20.77
21.50
283. 13
32.94
30.61
1.43
4.88
27.59
24.70
6.26
44.36
.24
9.07
9.07
5.63
ALPHA
1 .550
. 130
.380
.460
3.170
1 .300
.860
1 .230
.480
.210
.640
.670
1 .930
1 .250
.640
1 .690
.920
1 .970
.410
.940
1.320
.510
.540
.910
.530
1 .860
.410
1.310
1 .480
.570
.330
.600
2. 170
.500
.140
.440
.390
1.260
R(M)
.849
.714
.426
.030
.823
.068
.211
.002
.247
.504
. 158
.204
.448
.483
.029
.344
.646
.401
.293
.620
.630
.894
.387
.314
.360
.534
.550
.239
.054
.359
.391
.271
.433
.587
.016
.877
.877
.313
R(C)
.650
.530
.310
.400
.540
.050
.040
.050
. 100
.180
.040
.060
. 190
. 130
.080
.110
.350
.170
.470
.380
.230
.560
.440
.280
.410
. 160
.400
.160
.380
.490
.190
.480
.460
.410
.380
.570
.570
.380
A61
-------
YEAR : 1972 TO 1975
TOTAL NUMBER OF LAKES
493
TETRA TECH.,INC.
3700 MT. DIABLO BLVD.
LAP., CAL. 94549
: STORET
: CODE
: 1706
1712
1714
1725
1726
1735
1739
1740
1742
1748
1750
1751
1754
1755
1758
1761
1762
1763
1764
1766
1805
181 1
1827
1828
1828
1836
1837
1838
1840
1841
1842
1843
1844
1845
1846
1847
TIME-
DEPTH
1
1
1
2
1
2
1
2
2
1
2
1
1
2
2
2
2
2
2
3 2
3 2
TROPHIC
STATE
E
E
E
E
E
E
E
E
E
E
E
E
E
E
E
E
E
E
E
E
E
E
E
E
E
N M
N E
I E
N E
N E
N E
N M
N M
N E
N M
N M
WPN
297
301
302
309
310
313
315
306
317
320
322
318
307
305
316
321
312
295
319
308
324
327
334
336
337
344
345
347
348
346
349
335
342
326
338
339
: 1851 : 4 1 : N E : 323
: 1852 : 3 2 t I MU : 325
K1
2.38
1.13
5.88
3.39
1.73
.90
1 .67
1 .39
1.44
6.37
2.62
1.14
3.11
6.61
1.74
1.49
2.31
.36
.54
.92
2.70
2.51
2.68
1.22
2.55
.54
2.76
1.97
1.11
3.60
1 .81
.41
1.57
1.60
.95
.66
.55
.62
K2
3.60
4.96
12.03
18.95
.38
.79
5.28
.55
.71
19.74
8.80
2.91
5. 12
3.34
4.49
2.54
2. 14
6.41
.04
.17
5.53
4. 14
7.12
1 . 19
7.17
.43
7.45
6.87
1.11
1 .66
1 .59
.85
1.03
.17
3.47
.51
.30
1.40
K1*Z
6.43
3.38
6.23
5.42
5.72
4.22
8.33
5.84
5.76
8.92
6.54
5.23
8.39
15.87
2.09
2.67
2.78
1.11
8.75
1 .94
16.46
9.02
19.30
6.49
11 .99
3.60
5.79
9.08
10.06
21.93
18.86
3.03
17.72
17.28
11.09
8.01
1.00
3.77
K2*Z
9.73
14.87
16.84
. 30.32
1 .24
3.73
26.40
2.32
2.83
27.64
22.01
13.41
13.83
8.02
5.38
4.57
2.57
19.86
.65
.36
33.73
14.90
51.29
6.28
33.72
2.89
15.65
31 .62
10.1 1
10. 14
16.54
6.18
11.59
1 .87
40.55
6.21
.54
B.54
ALPHA
2.330
2.820
2.360
3.040
5. 150
1 .830
1 .270
5.250
3.760
2.600
2.050
1 .270
3.000
2.750
.940
1 .630
3.640
1 .380
2.460
.380
1 .800
1 .380
1 .980
.930
1 . 170
.360
.720
1 .640
.930
.630
.830
.510
.450
.530
.570
.500
1 .710
R(M)
.389
.796
.258
.623
.111
' .496
.655
.223
.255
.327
.563
.693
.347
.071
.598
.535
.286
.981
.121
.166
.432
.397
.498
.442
.524
.599
.495
.638
.476
.1 14
.326
.831
.294
.063
.794
.542
.495
.590 : .786
R(C)
.300
.470
.150
.230
.370
.530
.380
.420
.410
.140
.280
.470
.240
. 130
.370
.400
.300
.740
.650
.520
.270
.290
.270
.450
.280
.650
.270
.340
.480
.220
.360
.710
.390
.380
.510
.600
.640
.620
A62
-------
YEAR : 1972 TO 1975
TOTAL NUMBER OF LAKES
493
TETRA TECH.,INC.
3700 MT. DIABLO BLVD.
LAP., CAL. 94549
: STORET
CODE
1853
1854
1855
1856
1857
1901
1902
1903
1907
1908
190S
1910
1911
1912
1914
2001
2002
2003
2005
2006
2007
2008
2009
2010
2011
2012
2014
2015
2101
2103
2203
2204
2205
2210
2211
: 2215
: 2217
TIME-
DEPTH
2
2
1
2
3 2
4
2
1 1
3 2
3 1
2 2
1 1
1 1
3 1
3 2
4 2
1 1
1 1
1 1
1 1
3 1
3 2
1 2
3 1
1 1
1 2
1 2
3 2
1 3
1 3
1
1
1
1
1
1
1
TROPHIC
STATE
N M
N E
N E
N E
N E
p
E
E
E
E
E
E
E
p
E.
M
E
E
p .
E
E
E
E
E
E
E
E
M
M
E
c
E
E
E
MU
E
M
1 2220 tit t N E
WPN
331
332
340
333
328
494
495
496
500
501
502
503
504
505
507
511
512
513
515
516
517
518
519
520
521
522
524
525
351
353
529
530
533
538
539
543
528
535
K1
1.08
5.33
4.57
2.84
.74
1.18
1 . 16
1.16
.68
.93
.98
5.93
1.60
.90
.79
.48
1.29
2.63
4.01
2.17
.64
.97
1.27
.66
.48
.19
.78
.60
.27
.36
2.97
3.12
5.00
1 .42
3.19
2.55
1.37
K2
1.64
14. 19
5.27
.56
.50
2.78
3.79
.33
1 .18
2.38
4.44
54.54
11.79
.47
.48
.26
3.43
6.49
12.05
16.72
1 .06
1 .52
12.73
1 .34
6.04
.26
16.58
.86
1 .02
2.08
7.31
11.25
17.61
.02
7.02
3.77
.73
5.36 : 3.54
K1*Z
7.89
27. 18
21.00
17.35
4.69
3.53
7.80
1.97
4.96
3.08
6.55
17.78
4.32
1.08
4.58
4. 12
5.05
6.80
8.01
9.77
2.63
5.83
9.91
3.32
5.48
7.62
14.62
5.04
30.80
32.60
6.23.
4.37
8.01
3.83
8.30
5.10
5.60
K2»Z
1 1 .99
72.35
24.26
3.39
3.17
8.33
25.37
.56
8.64
7.84
29.73
163.62
31.83
.56
2.77
2.24
13.39
15.57
24.09
75.24
4.35
9. 10
99.28
6.72
25.32
1.69
135.99
7.20
24.78
49.63
15.36
15.75
28.17
.05
18.24
7.54
3.00
2. 68 1.77
ALPHA
.340
.750
.830
.650
.380
1 .840
.670
4.370
1 . 120
1 .440
•2.440
2.000
2.850
2. 120
1 .090
.860
3.830
7.980
7.860
5.040
3.770
1 .000
1 .410
2.250
3.110
3.050
1 .790
.970
.870
.770
1 .200 .
.980
1 .600
1 .910
1.330
2.240
.910
R(M)
.585
.333
.202
.064
.476
.667
.737
.197
.720
.732
.823
.608
.822
.365
.433
.529
.672
.447
.429
.780
.721
.617
.887
.753
.757
.157
.839
.704
.387
.527
.454
.536
.413
.009
.408
.367
R(C)
.480
. 160
. 180
.260
.570
.460
.460
.460
.600
.520
.510
. 140
.380
.530
.560
.670
.440
.260
.200
.320
.610
.510
.440
.600
.400
.460
.360
.630
.440
.420
.250
.240
. 170
.410
.240
.280
.282 .420
2.010 .110 : .160
A63
-------
YEAR : 1972 TO 1975
TOTAL NUMBER OF LAKES
493
TETRA TECH..INC.
3700 MT. DIABLO BLVD.
LAP., CAL. 94549
: STORET
CODE
2304
2306
2308
2303
2310
231 1
2312
2313
2314
2402
2403
2408
240S
2502
2503
2507
2508
2513
2603
2606
260S
2617
2618
2629
2631
2643
2648
265S
2673
2683
2685
2688
2691
2692
2694
: 2695
: 2696
1 2699
1
I
:
;
;
t
.
;
t
t
t
i
:
i
riME-
3EPTH
1
3 2
1
3 2
3 2
» 3
2
» 2
1 1
3 2
2
1 2
1 t
1 1
1 1
1 1
1 1
1 1
1 1
1 2
1 2
» 2
» 2
1
3 2
1 1
1 1
1 2
1 1
1 1
1 1
1 2
1 1
1 2
t 1
» 2
3 1 i
1 2 i
TROPHIC
STATE
I E
N M
N M
N 0
N 0
N 0
N E
NM
m
N 0
M
M
E
E
HE .
E
HE
E
E
E
N E
I E
N 0
N E
I E
N HE
N E
N HE
N E
I E
N E
N E
N E
Nc
c
Nf"
t
N 0
N 0
N E
N E
WPN
*i
4
8
2
Q
5
9
7
5
355
357
358
356
220
27
223
221
219
182
183
184
188
189
193
194
199
200
203
209
215
216
217
202
211
191
195
196
213
Kl
5.76
.92
2.96
.58
.59
.43
1.35
.56
3.73
.94
.94
1.58
B.24
3.79
7.70
21.53
38.97
26.06
7.24
2.13
3.81
.56
.49
4.90
.73
3.31
2.17
4.03
13.28
5.74
13.64
2.56
2.22
3.42
.55
.25
.86
5.27
K2
1 .99
.84
3.94
.28
.34
.25
.75
.40
3.21
1 .91
.99
1 .07
12.46
39. 15
31 .42
143.89
802.83
189.68
16.08
.04
4.80
.54
.41
5.60
.48
3.33
12.57
.21
29.67
8.79
21 .58
1.88
1.62
1.19
.85
.15
.79
7.85
K1*Z
17.56
9.55
10.84
9.52
8.51
13.21
8. 10
7.47
15.92
7.58
12.24
23.99
17.31
5.75
18.78
26.27
35.46
31.27
24.24
12.99
23.24
9.31
4.14
21.36
7.39
6.66
7.95
28.26
20.19
24.53
11.60
17.54
8.79
17.71
2.34
3.78
2.00
35.49
K2*Z
6.08
8.69
14.41
4.65
4.89
7.59
4.52
5.33
13.69
15.50
12.90
16.29
26.18
59.51
76.66
175.55
730.58
227.61
53.85
.25
29.29
8.97
3.46
24.42
: 4.84
6.70
45.99
1 .46
45.09
37.54
18.34
12.92
6.42
6.14
3.59
2.25
1.84
52.92
ALPHA
1 .040
.410
.970
.390
.380
.290
.470
.480
.470
.410
.520
.750
.940
.050
1 .750
1 .230
3.980
1.110
1 .890
.910
1 .220
.360
.400
1 . 170
.500
.780
2. 170
.820
1 .580
.860
1 . 150
.580
.780
.560
.480
.250
.620
.580
R(M)
.057
.497
.310
.458
.492
.572
.292
.562
.187
.686
.528
.301
.155
.732
.347
.237
.346
.218
.235
.009
.249
.634
.632
. 189
.471
.233
.727
.013
. 144
.2)0
.104
.224
.248
.092
.735
.701
.516
.221
R(C)
.150
.520
.250
.630
.630
.700
.430
.640
.210
.520
.520
.390 •
.110
.210
. 120
.040
.030
.040
.120
.320
.210
.640
.670
.170
.580
.230
.320
.200
.070
.150
.070
.280
.310
.230
.640
.800
.540
.160
A64
-------
YEAR : 1972 TO 1975
TOTAL NUMBER OF LAKES : 493
TETRA TECH.,INC.
3700 MT. DIABLO BLVD.
LAP.. CAL. 94549
STORET
CODE
27A1
27A2
27A5
27A6
27A7
27B1
27B2
27B3
27B4
27CO
27C1
27C2
2702
2705
2709
27) 1
2712
2713
2715
2716
2719
2725
2737
2739
2746
2750
2756
2757
2761
2765
2776
2782
2783
t 2788
: 2793
! 2802
2804
t 2805
TIME-
DEPTH
3 1
2
2
1
2
3 1
4 2
1
2
2
2
1
1
3 1
3 1
4 1
1 1
3 1
1 2
3 2
1 2
1 1
3 2
1 1
4
4
1
1
4 2
4
1
3 1
1 1
3 2
4 2
3 2
! 1 1
! 3 2
TROPHIC
STATE
N E
N E
t E
t E
I E
Nc
c
N MU
N E
N MU
N E
N E
N E
N E
N E
N E
N E
N E
N E
N M
N E
N E
N E
N E
N E
N M
N E
N E
N E
N E
N M
N E
N E
N E
: N M
t N E
: I E
t I E
t I E
WPN
135
136
137
127
122
133
101
117
96
81
84
115
80
83
85
86
87
88
92
93
94
97
102
103
105
108
11 1
1 12
114
118
123
125
126
129
131
360
362
363
Kt
.55
3.15
4.46
12.46
3.95
.85
.52
1 .38
1.07
2.79
1.17
1.03
2.24
.70
.78
.49
1 .20
.66
1.08
.86
.94
1 .08
.58
1 .64
.44
.55
3.01
2.53
.28
.55
8.04
.51
3.18
.65
.24
.94
2.73
.97
K2
6.89
1 .42
25.08
4.58
7.53
.95
.56
2.45
.45
4.50
.75
19. 18
2.02
.67
.29
7.81
.86
2.02
2.37
.69
2.30
.2)
1 .47
.23
.95
26.04
2.65
.71
.27
26.21
.10
12.71
1.57
.65
3.24
9.11
.20
K1*Z
.74
26.90
24.52
30.40
34.67
1 .08
3.33
6.32
6.63
22.08
11 .37
1.35
2.39
1 .82
2.60
2.21
5.31
3.79
8.22
4.43
7.16
3.38
5.34
1 .49
2.07
2.17
6.40
6.94
1 .68
1.34
27.17
1.08
6.11
7.86
3.63
14.64
10.09
IS. 98
K2*Z
9.24
12.08
137.92
11.17
66.14
1 .22
3.59
11.22
2.76
35.63
7.33
25.13
2.17
1 .73
.01
1 .32
34.52
3.81
15.42
12.29
5.29
7.22
1 .88
1 .33
1 .08
3.74
55.46
7.25
4.21
.64
88.61
.20
24.40
19.01
9.97
50.16
33.71
3.25
ALPHA
2.050
1 .000
.820
2.780
1 .260
3.470
.480
.720
.380
.890
.540
6.300
.420
2.230
1 .280
.660
.750
.850
.670
.720
.630
.650
.450
3. 140
.610
1 . 170
1 . 100
.940
.790
.720
3.930
2.840
1.370
.480
.430
1.660
1.S90
1.110
R(M)
.958
.125
.558
.029
.326
.572
.675
.562
.279
.367
.356
.948
.288
.574
.006
.550
.844
.539
.635
.764
.440
.664 •
.376
.352
.542
.759
.742
.292
.899
.465 '
.289
.270
.556
.789
.920
.784
.550
.174
R(C)
.650
.240
.180
.070
.200
.540
.660
.420
.480
.260
.460
.490
.310
.590
.560
.670
.450
.540
.480
.540
.520
.480
.630
.380
.700
.650
.250
.280
.780
.640
.110
.660
.240
.610
.810
.510
.270
.510
A65
-------
YEAR : 1972 TO 1975
TOTAL NUMBER OF LAKES
493
TETRA TECH..INC.
3700 MT. DIABLO BLVD.
LAP., CAL. 94549
STORET
CODE
2806
2902
2903
2905
3001
3002
3003
3005
3007
3008
3009
3010
301 1
30)2
3013
3014
3016
3101
3102
3103
3104
3105
3106
3107
31 10
3201
3202
3204
3206
3302
3303
3305
3306
3402
: 3403
: 3406
TIME-
DEPTH
3 2
1 2
3 2
3 1
1 2
2 2
1 2
1 2
4 2
4 3
3 2
1 2
1 3
3 3
1 2
1 2
3 3
3 2
3 2
1 2
3 2
1 2
3 2
3 1
3 2
4 3
1 2
3 1
2
1
4 2
2
: 3409 : i
i 3410 1 1
TROPHIC
STATE
E
E
c
E
E
E
N 0
I MU
N MU
N 0
I E
N MU
N M
N OM
x
MU
E
0
E
HE
E
E
E
MU
E
E
LM
E
E
E
E
0
E
E
E
E
E
E
E
WPN
361
548
549
550
790
791
792
794
796
797
798
799
800
801
802
803
804
554
555
556
557
558
559
560
562
808
807
809
811
14
11
13
12
364
367
370
372
373
Kl
.96
1.08
.97
.92
1 .40
.99
1.27
1.46
.23
.56
.75
1.70
2.07
.60
1.07
2.17
.63
.60
.86
1.19
.93
3.65
.65
.58
.86
.53
1 .99
.93
1 .18
7.53
.49
15.46
11.28
1.59
1.03
2.20
3.37
12.86
K2
. 10
.74
3.38
1.12
1 .56
.68
.84
.37
.07
.28
2.68
1 .74
3.08
. 12
1 .51
33.27
.50
1 .48
2.87
22.53
3.84
6.40
1 .67
1 .01
1 .43
3.95
3.67
.83
1 .57
6.11
.81
116.10
59.36
.47
1 .03
2.32
16.77
242.73
K1*Z
15.77
10.24
7.08
3.79
24.34
15.63
17.18
11.95
1 .98
25.54
4.30
31 .02
45.41
41 .47
16.39
13.21
20.64
3.31
6.69
6.92
5.47
22.24
12.82
2. 16
6.25
31.45
13.35
4.27
18.64
18.61
6.47
34.94
37.77
2.87
5.34
9.02
6.07
K2*Z
1 .58
7.05
24.68
4.58
27.22
10.72
1 1 .29
3.07
.59
12.66
15.26
31 .85
67.43
8.52
23. 16
202.95
16.44
8. 12
22.39
130.69
22.63
39.02
33.08
3.73
10.45
233.23
24.61
3.82
24.79
15.09
10.56
262.39
198.85
.85
5.37
9.49
30.19
• 23.14 : 436.92
ALPHA
2.560
1 .050
.710
5.250
.960
.570
.250
.390
.390
. 190
1 .320
.420
.230
.350
1 . 180
1 .960
.280
1 . 120
2. 130
1 .720
1 .680
2. 160
.530
1 .030
1 .500
.210
2.210
1.910
.370
1 .220
.250
.750
.870
1 .330
.490
1 .340
1 .010
1.330
R(M)
.095
.390
.782
.566
.444
.409
.341
.150
.563
.470
.824
.377
.417 •
.255
.569
.877
.559
.803
.796
.941
.817
.325
.800
.747
.661
.933
.480
.490
.530
.097
.768
.327
.318
.157
.495
.324
.596
.595
R(C)
.510
.480
.510
.520
.420
.500
.440
.410
.810
.640
.570
.370
.330
.620
.480
.320
.610
.620
.540
.460
.520
.220
.610
.630
.540
.650
.330
.520
.460
. 120
.670
.060
.080
.390
.490
.310
.230
.070
A66
-------
YEAR : 1972 TO 1975
TOTAL NUMBER OF LAKES
493
TETRA TECH.,INC.
3700 MT. DIABLO BLVD.
LAP., CAL. 94549
STORET
CODE
3412
3415
3419
3420
3423
3501
' 3502
3503
3505
3506
3507
350S
3604
3605
3606
3608
361 1
3617
3632
3633
3635
3637
3639
3640
3641
3701
3702
3704
3705
3706
3707
3711
3713
3715
3716
: 3717
: 3718
t 3719
TIME-
DEPTH
1
2
1
2
2
3 2
4 2
3 2
3 2
1 2
1 1
3 2
4 3
1 2
1 2
4 3
1 2
4 3
1 2
1 2
4 3
1 2
3 2
1 2
1 2
1 2
1 2
1 3
1 2
1 1
1 3
1 2
1 2
1 2
1 2
1 2
1 3
1 1
TROPHIC
STATE
E
£
E
£
M
E
MU
M
E
MU
E
M
N 0
I E
N M
N M
N E
N 0
N M
N E
N M
I E
N E
N E
ME
E
E
M
E
£
M
M
E
E
M
E
E
: N M
WPN
365
368
371
374
376
817
818
819
821
822
823
824
149
150
151
153
157
160
167
168
170
172
156
162
147
377
378
379
380
381
382
386
387
388
389
390
392
391
Kl
14.40
.77
9.11
1.11
.59
.76
.42
.57
.67
1 .06
2.13
.86
.26
1.32
3.10
.30
7.46
.36
1.48
1.56
.17
1 .99
.77
1 .82
2.18
3.60
7.49
1 .43
3.34
3.70
1.77
5.48
1 .24
4.12
1.51
4.86
4.93
1.23
K2
378.34
.48
15.99
.82
.04
3.99
.04
5. 13
13.26
1.29
1 .98
6.82
. 13
4.20
3.69
. 10
16.31
. 14
.79
2.78
.12
5.61
.80
.40
2.73
3.54
46. 1 1
1 .81
4.65
16.05
2.56
9.51
3.22
15.21
1 .09
4.79
: 24.98
: 1.08
K1*Z
20.17
4.21
16.39
8.77
6.68
6. 19
2.79
6.77
12.22
19.41
4.47
6.87
10. 19
25.31
16.69
16.26
40.98
8.05
11.27
12.35
15.27
26.74
6.87
9.30
31 .36
51.18
86.85
59.02
31.73
18. 12
37.78
29.57
12.63
26. 10
25.30
47.13
111.81
1.84
K2*Z
529.68
2.63
28.79
6.46
.45
32.31
.28
60.54
242.65
23.55
4.15
54.56
5.00
80.71
19.91
5.24
89.53
3.18
6.03
22.03
10.49
75. 18
7.09
2.04
39.38
50.22
534.86
74.76
44. 14
78.67
54.61
51.35
32.82
96.46
18.28
46.48
566.97
1.62
ALPHA
1 .650
.490
1 .470
.590
.290
1 .890
3. 140
1 .270
2.550
1 .740
5.080
1 . 170
.270
.300
.640
.510
.850
.330
.360
.410
.280
.660
.300
1 . 180
.660
1 .870
2.600
.530
1 .460
2.400
.690
.500
. 120
.720
.370
.880
.940
.390
R(M)
.646
.450
.162
.399
. 103
.872
.195
.940
.967
.534
.304
.902
.652
.707
.278
.520
.226
.525
.265
.534
.800
.585
.572
. 108
.366
.214
.451
.470
.294
.540
.449
.241
.677
.473
.324
.169
.507
.416
R(C)
.060
.570
. 100
.470
.630
.570
.710
.640
.600
.490
.320
.540
.790
.430
.240
.770
.120
.740
.400
.390
.850
.330
.560
.350
.310
.220
.120
.410
.230
.210
.360
. 150
.450
.200
.400
.170
.170
.450
A67
-------
YEAR : 1972 TO 1975
TOTAL NUMBER OF LAKES : 493
TETRA TECH..INC.
3700 MT. DIABLO BLVD.
LAP., CAL. 94549
STORET
CODE
3801
3804
3807
3808
3812
3814
3901
3902
3905
3906
3907
3908
3912
3914
3921
3924
3927
3928
3929
3930
3931
3932
4001
4002
4003
4004
4005
4006
4008
4009
4010
4011
4012
4013
4014
4101
i 4104
! 4106
TIME-
DEPTH
1 1
3
3
1
3 :
I
!
1 2
3 2
4 2
3 2
1 2
4 2
3 2
1 1
1 2
3 2
1 2
1 2
1 2
4 2
1 3
TROPHIC
STATE
E
E
E
E
OU
E
E
E
E
p
E
E
p
£
p
E
E
E
E
E
E
E
E
M
E
E
E
E
E
E
E
g
E
E
E
E
13: E
12:1 E
WPN
565
568
571
572
575
577
394
396
397
398
399
400
401
403
406
408
411
393
395
402
407
409
581
582
583
584
585
586
588
589
590
591
592
593
594
827
830
832
K1
1.10
.85
.73
1.25
.80
1.41
10.55
1.25
4.28
2.96
3.98
6.37
3.91
1 .44
.94
3. 12
1.13
1 .47
2.12
1 .89
6.49
1 .60
.69
.56
.85
1 .09
.36
.79
10.62
1 .68
.58
2.59
1 .83
1 .23
.26
3.04
1.55
16.13
K2
.29
.57
.38
.89
8.56
1 .64
22.20
. 15
3.87
2.22
1 1 .34
42.03
2.75
3.84
.75
2.64
.56
4.0t
14.12
14.63
22.85
6. 16
.84
1 .03
.13
.70
1 .96
.15
30.94
2.53
1 .28
8.24
5.27
1 .28
1 . 16
7.91
.29
K1*Z
4.38
2.90
3.66
5.24
15.06
4.08
12.66
2.38
7.28
14.82
13.12
19.1 1
7.43
9.37
2.54
14.98
3.39
6.90
10.38
7.35
31.17
8. 18
4.44
5.24
4.32
10.98
2.32
9.42
19.12
18.33
5.30
19.91
10.43
19.13
1.57
96.21
60.74
41.76 : 183.94
K2*Z
1 . 16
1 .94
1 .88
3.72
161.81
4.76
26.64
. .29
6.58
11.12
37.41
126. 10
5.22
24.94
2.02
12.65
1 .69
18.87
69. 19
57.07
109.67
31 .41
5.35
9.64
.65
7.07
12.54
1 .82
55.69
27.61
1 1 .64
63.45
30.05
19.80
6.95
249.93
1 1 .49
476.10
ALPHA
1 .480
.810
.410
2.630
.560
.290
5. 150
4.310
2.680
2. 100
3.800
2.670
4.550
1 .530
1 .060
1.010
2.440
1 .280
1 .480
.680
2.570
1 .540
1 .720
1.010
1 .440
3.930
1 .040
3.830
3.860
1 .880
1 .500
3.590
3.920
.870
1.620
.570
.900
.640
R(M)
.194
.438
.413
.362
.931
.454
.166
.089
.174
.202
.418
.509
.152
.648
.457
.213
.307
.651
.759
.805
.351
.705
.635
.768
. 151
.372
.937
.196
.215
.473
.791
.552
.611
.456
.944
.460
.109
R(C)
.480
.540
.580
.440
.560
.420
.090
.440
.190
.250
.200
. 140
.200
.410
.510
.240
.470
.410
.320
.350
.130
.380
.590
.640
.540
.480
.730
.560
.090
.370
.630
.280
.350
.450
.790
.250
.390
.138 : .060
A68
-------
YEAR : 1972 TO 1975
TOTAL NUMBER OF LAKES
493
TETRA TECH.,INC.
3700 MT. DIABLO BLVD.
LAF., CAL. 94549
STORET
CODE
4107
4201
4204
4207
4213
4216
4219
4220
4221
4222
4223
4224
4225
4226
4227
4229
4402
4403
4503
4504
4505
4506
4507
4508
4511
4513
4515
4602
4603
4610
4620
4624
4626
4627
4629
4704
TIME-
DEPTH
1
1
;
;
.
2
1
2
1
) 1
1
2
1 2
1 2
} 2
1
2
1 1
1 1
1 2
1 2
2
1 1
1 2
1 1
1 2
3 2
1 1
1 1
3 2
3 2
3 2
4 1
1 1
4 2
3 1
1 2
4707 1 2
TROPHIC
STATE
N MU
I E
N E
r
r
:
! 4708 i 1 2 t
E
E
E
M
M
E
M
M
M
: E
t M
M
E
E
E
MU
E
ME
MU
E
LM
MU
M
M
0
E
£
E
E
E
E
WPN
833
415
417
418
425
426
413
414
416
419
420
421
422
423
424
428
28
29
430
431
432
434
436
437
441
433
438
599
600
607
617
621
623
624
626
443
445
Kl
2.05
5.81
1.85
2.70
.85
4.18
1.82
1.62
2.04
.80
1.10
4.16
5.04
2.25
3.13
1.26
8.27
7.27
7.55
2.23
1.10
2.88
1.02
2.35
3.06
.97
7.87
1 .08
.83
.71
.78
.14
5.48
.53
.59
2.96
1.41
446 6.15
K2
1 .55
30. 14
1 .48
26.05
.73
6.03
16.13
1 .09
1 .83
1 .60
1 .07
.64
3.76
.76
1 . 10
.32
13.69
26.74
5.27
16.98
5.45
10.91
2.69
.02
14.23
.26
41 .93
1 .30
5.74
.08
4.85
.24
8.65
.20
1 .55
8.14
3.38
7.04
K1*Z
20.31
9.30
13.52
13.50
3. 14
10.46
13.31
20.79
17.94
8.83
4.72
3.75
17.14
6.08
1 1 .59
10.72
20. 18
11.05
40.76
15.17
15.23
11.51
12.99
10.10
21 .40
14.75
31 .48
3.99
7.55
7.43
12.79
.66
4.38
5.37
2.17
39.39
21 .08
K2*Z
15.37
48.23
10.79
130.26
2.71
15.08
1 17.72
13.93
16.09
17.63
4.59
.58
12.78
2.06
4.08
2.71
33.41
40.64
28.47
1 15.46
75.82
43.66
34.13
.07
99.64
4.00
167.73
4.81
52.23
.86
79.53
1 .08
6.92
2.08
5.73
108.32
50.37
33.21 38.01
ALPHA
-.030
1 .040
.490
1 . 130
.890
1 .250
.450
.360
.620
.270
.510
.960
2. 060
1 .060
.970
.400
1 .080
1 .840
3.970
1 .620
.680
2. 120
.720
1 .290
1 .680
.430
2.650
.980
.730
.250
.220
.330
.980
.290
.280
.840
.990
1 .730
R(M)
.270
.472
.301
.781
.505
.256
.829
.292
.306
.713
.470
.036
. 129
. 131
. 101
. 167
. 167
.336
.085
.773
.820
.569
.720
.003
.604
.218
.404
.528
.893
. 141
.889
.920
.224
.424
.818
.481
.628
.157
R(C)
.330
. 150
.350
.270
.540 •
. 190
.350
.380
.330
.550
.480
.190
. 170
.310
.240
.440
. 110
. 120
. 120
.310
.480
.260
.490
.300
.250
.510
. 110
.480
.550
.590
.560
.870
.150
.650
.630
.250
.410
.140
A69
-------
YEAR : 1972 TO 1975
TOTAL NUMBER OF LAKES : 493
TETRA TECH.,INC.
3700 MT. DIABLO BLVD.
LAF., CAL. 94549
STORET
CODE
471 1
4712
4713
4717
4722
4723
4724
4725
4728
4B01
4802
4803
4805
4806
4808
4809
4810
481 1
4812
4813
4814
4815
4816
4817
4818
4B19
4820
4821
4822
4823
4824
4825
4826
4827
4828
4829
4830
t 4831
TIME-
DEPTH
1 2
1 2
1 1
1 2
1 2
1 2
1 2
1 3
1 2
4 2
4 2
3 2
3 2
3 2
4 2
2 2
4 2
1 1
1 1
1 2
3 2
2 2
3 2
1 1
1 1
3 2
1 2
1 2
3 2
4 2
3 1
2 2
4 2
3 2
4 2
2 1
3 1
TROPHIC
STATE
2 2 :
E
E
M
E
E
E
E
MU
E
M
MU
MU
E
E
E
M
E
E
E
MU
E
E
E
E
E
E
E
E
MU
M
E
MU
E
E
E
E
E
M
WPN
447
446
449
446
446
444
455
443
455
631
632
633
635
636
638
639
640
641
642
643
644
650
646
647
648
649
651
645
652
653
654
655
656
657
658
659
660
661
Kl
1.82
5.11
6.56
10.06
4.33
1.62
1 .05
.99
2.07
.51
.45
1 .00
.80
.77
.22
.73
.51
1 .44
1.53
1 .00
.67
.99
.60
2.56
1.28
.78
1.67
2.56
.61
.34
.87
1.00
.35
.61
.37
1.02
.63
.86
K2
4.57
8.83
40.45
11.81
5.36
.30
.68
5.43
1 .21
4.47
1 .67
10.32
1 .21
2.82
2.92
.35
3. 13
.66
4.91
.72
2.12
.81
4.78
5.38
2.09
3.69
. 19
.55
26.43
5.07
6.21
.02
.27
2.60
.51
4.38
1 .29
K1*Z
25.67
38.82
32.80
71.45
34.20
13.76
15.99
26.21
11.80
8.47
2.50
10.77
4.83
10.11
1 .22
10.23
3.05
6.06
5.65
6.43
3.75
5.94
3.16
9.46
5.27
5.07
10.84
17.13
8.44
5.46
4.25
11.16
2.25
4.71
2.50
4.39
2.22
9.77
K2«Z
64.48
67.08
202.25
83.88
42.33
2.53
10.39
143.27
6.88
73.76
9.36
1 1 1 .43
7.24
36.98
16.07
4.85
.01
13. 16
2.43
31 .42
4.01
12.74
4.27
17.67
22.07
13.59
23.99
1.26
7.63
422.81
24.84
69.60
.16
2.11
17.41
2. 18
15.34
14.56
ALPHA
.980
1 .690
1 .070
1 .560
1 .680
.690
.480
.520
.750
.450
.560
.360
1.910
.830
1 . 160
.500
2.040
2.290
1 .690
1 .900
2.560
2.400
1 .260
3.690
.810
3.910
1 .470
1 .300
.390
1.010
.860
.580
2.720
.950
1 .370
1 .810
3.650
.590
R(M)
.580
.253
.485
. 104
.222
.102
.382
.846
.220
.944
.893
.912
.651
.826
.983
.394
.004
.601
.219
.830
.615
.684
.694
.422
.765
.775
.570
.028
.598
.996
.871
.862
.168
.422
.949
.327
.916
.633
R(C)
.350
. 160
. 130
.090
. 190
.380
.490
.500
.330
.660
.690
.500
.550
.560
.820
.580
.660
.410
.400
.500
.600
.500
.630
.280
.440
.560
.370
.280
.620
.750
.540
.500
.740
.620
.730
.490
.610
.540
•-*•
-------
YEAR : 1972 TO 1975
TOTAL-NUMBER OF LAKES
493
TETRA TECH.,INC.
3700 MT. DIABLO BLVD.
LAP., CAL. 94549
STORET
CODE
4B32
4834
4835
4837
4838
4839
4901
4903
4904
4906
4908
4909
4910
4913
4914
4915
4917
4920
4921
4923
4924
4925
5001
5002
5005
5007
5008
5010
5011
5103
5105
5106
5108
51 10
5111
i 5112
TIME-
DEPTH
4 2
1 2
2 2
4 2
4 2
2 2
4 2
1 2
1 2
4 3
1 2
1 2
1 2
3 2
3 2
4 1
1 2
3 2
3 2
1 1
3 1
4 2
3 2
1 1
1 2
1 1
3 2
1 1
1 2
1 3
1 2
1 2
1 1
4 3
1 2
1 1
TROPHIC
STATE
: 5113 : 1 2 1
> 5306 1 1 2 t
E
E
M
E
MU
E
0
p
^
ME
M
g
0
E
E
E
g
£
M
M
HE
E
M
E
M
E
E
E
M
E
M
E
E
ME
E
g
WPN
662
663
664
666
667
668
836
837
838
839
841
846
847
850
851
852
854
857
858
860
861
862
154
15
20
16
19
17
18
460
463
462
464
465
458
459
E : 466
0 : 869
Kl
.56
1.45
.99
.26
.28
1.37
.21
1.31
1.65
.13
1.07
1.17
1.62
.84
.68
.17
1.23
.78
.70
2.55
.63
.56
.67
10.01
2.17
19.39
.76
10.17
2.10
2.41
1.76
1.71
3.68
.56
3.44
2.89
4.71
1.29
K2
2.25
3.15
.80
. 10
.48
5.79
.09
.91
1 .27
.02
.51
.42
.03
.35
.16
.59
1.37
4.45
4. 87
.87
. 18
.04
1 .16
17.99
.98
96.31
.43
38.45
1 .37
6.03
7.35
12.91
21 .74
5.35
.79
2.27
12.04
2.79
K1*Z
4.29
8.27
18.72
1.63
1.83
11 .09
2. 18
26.17
25.25
3.36
17.49
6.57
22.81
5.30
4.36
.52
12.43
5.08
13.96
7.64
1 .33
3.28
13.01
33.54
22.44
32.57
11.89
31.94
26.62
70.01
31 .71
18.35
18.05
19.67
24.11
14.18
28.71
K2*Z
17.31
17.97
15.17
.63
3.14
46.91
.93
18.18
19.41
.59
8.33
2.36
.46
2.18
1 .02
1.77
13.80
28.94
96.92
2.62
.37
.24
22.43
60.26
10.16
161 .81
6.68
120.74
17.42
174.94
132.24
138. 18
106.52
187.94
5.54
11.10
73.47
24.07 52.23
ALPHA
1 .420
1 .090
.460
1 .170
.860
.760
.240
.710
1 . 100
-.070
.590
.480
.480
1 . 100
-.070
.880
3.520
.870
.480
.700
6.610
1 .310
.480
.800
.540
1 .000
.520
.840
.570
.960
.650
.290
.360
.570
.540
. 190
.480
.260
R(M)
.879
.600
.450
.597
.859
.756
.666
.346
.318
.576
.307
.235
.012
.329
.256
.951
.474
.879
.908
. 1 19
.307
. 1 17
.720
.152
.173
.204
.423
.271
.238
.509
.703
.815
.616
.945
.063
.213
.352
R(C)
.640
.410
.500
.790
.780
.420
.820
.430
.380
.890
.480
.460
.380
.540
.590
.850
.450
.560
.590
.280
.610
.640
.600
.090
.320
.050
.570 .
.090
.320
.290
.360
.370
.210
.640
.230
.260
.180
.628 : .440
A71
-------
YEAR : 1972 TO 1975
TOTAL NUMBER OF LAKES
493
TETRA TECH.,INC,
3700 MT. DIABLO BLVD.
LAP., CAL. 94549
: STORET
CODE
5309
5311
5312
5401
5402
5403
5404
5508
5513
551S
5520
5522
5531
5538
553S
5541
5546
5548
5550
5555
5556
5559
5564
5565
5570
5574
5601
5602
5603
5605
5606
: 5607
: 5608
: 5609
: 5610
: 5613
: 5614
TIME-
DEPTH
1 2
3 2
1 1
1 2
1 2
1 3
1 2
1 1
3 2
4 3
1 2
1 1
3 2
1 1
3 1
1
1
1
2
1
2
1
4 2
1
1
1
o
2
2
3 3
3 3
1 2
4 2
4 1
1 3
1 1
1 3
TROPHIC
STATE
I E
N MU
N M
I E
1 M
I M
I M
N E
N E
N M
N E
I E
N E
N E
N E
I E
N E
N E
N E
I E
I E
B HE
N M
I E
N E
I M
I E
N 0
I E
I ME
N 0
I E
I E
N E
I ME
t E
I ME
WPN
872
874
875
467
468
469
470
34
36
39
40
41
43
45
48
49
51
53
54
58
59
52
46
33
38
56
881
882
883
885
886
887
888
889
890
893
894
K1
1.12
.76
1.97
10.27
5.58
2.70
4.31
1.58
.60
.22
1.64
3.95
.81
5.29
.81
3.35
6.03
1.17
1.37
9.96
4.66
4.39
.52
1.52
5.63
1.75
1 .16
1 .42
1.16
.65
.63
1.18
.26
.48
1 .03
2.50
1.52
K2
1 .01
.22
2.92
11 .73
46.61
.79
1.76
.09
.44
.04
.09
4.14
.86
.90
.20
. 13
5.18
1.51
1 .43
5.37
3.92
13.86
. 10
.78
5.92
.33
.24
1 . 10
12.88
2.84
. It
3.54
5.39
1 .87
2.78
9.05
33.85
K1*Z
6.61
13.39
3.55
59.54
71.40
56.70
75.06
6.73
4.56
6.91
8.49
6.39
8. CO
11.26
2.61
4.69
24.41
4.43
7.23
18.22
41 .02
8.44
2.94
7.23
6.87
7.99
6.71
17.30
12.08
22.15
15.48
21 .53
1 .66
2.01
26.46
12.25
40.73
K2*2
5.98
3.83
5.26
68.02
596.56
16.69
30.66
.38
3.36
1 .26
.47
6.71
8.50
1 .92
.64
.18
20.98
5.71
7.54
9.82
34.57
26.62
.56
3.73
7.23
1.53
1.37
13.43
133.96
96.15
2.57
64.72
35.03
7.86
71 .27
44.33
907.11
ALPHA
1.210
.360
.230
2.000
.580
.340
.500
1 .470
.360
. 180
.840
2.500
.610
2.830
.530
4.660
.880
1 .910
.560
.980
1 .510
1 .790
.540
1 .300
1 .380
1 .280
5.280
.410
1 .660
.360
.040
1 .440
1 . 180
2.530
1 . 100
1.750
.370
R(M)
.447
.274
.429
.100
.600
.098
.086
.035
.552
.456
.033
.210
.568
.031
.233
.012
.125
.524
.432
.051
.153
.418
.266
.253
.158
.099
. 150
.354
.905
.869
.208
.719
.988
.891
• .723
.592
.936
R(C)
.470
.570
.340
.090
.150
.270
. 190
.390
.630
.820
.380
.200
.550
. 160
.550
.230
. 140
.460
.420
.090
. 180
. 190
.660
.400
. 150
.360
.460
.410
.460
.600
.610
.460
.800
.680
.490
.290
.400
N » NUMBER OF LAKES WITH NON-ZERO DATA
A72
-------
YEAR : 1972 TO 1975
TOTAL NUMBER OF LAKES
493
TETRA TECH.,INC.
3700 MT. DIABLO BLVD.
LAP., CAL. 94549
: N
: MEAN
: STD. DEV.
! MAXIMUM
: RELATED STORET NO.
! MINIMUM
t RELATED STORET NO.
493
2.75
3.86
38.97
2508
.13
4906
491
10.43
44.62
B02.83
2508
.02
2210
493
15.81
17.77
183.94
4106
.52
4915
493
44.20
91 .44
907.11
5614
.01
2709
493
1 .347
1 .324
15.690
0502
-.070
4906
493
.458
.260
.996
4823
.002
0905
493
.405
. 192
.890
4906
.030
2508
N • NUMBER OF LAKES WITH NON-ZERO DATA
A73
-------
TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
1. REPORT NO.
EPA-560/11-79-011
2.
3. RECIPIENT'S ACCESSION NO.
4. TITLE AND SUBTITLE
5. REPORT DATE
Effect of Phosphorus Control Options on
Lake Water Quality
September, 1979
6. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
Marc W. Lorenzen
8. PERFORMING ORGANIZATION REPORT NO
TC-3930
9. PERFORMING ORGANIZATION NAME AND ADDRESS
10. PROGRAM ELEMENT NO.
Tetra Tech, Incorporated
3700 Mt. Diablo Boulevard
Lafayette, CA 94549
11. CONTRACT/GRANT NO.
68-01-3961
12. SPONSORING AGENCY NAME At\'D ADDRESS
Environmental Protection Agency
Office ofToxic Substances
Washington, D.C. 20460
13. TYPE OF REPORT AND PERIOD COVERED
Final Report
14. SPONSORING AGENCY CODE
15. SUPPLEMENTARY NOTES
Justine Welch, Project Officer
16. ABSTRACT
Data collected as part of the National Eutrophication Survey (NES) were
used to test the consequences of eight different phosphorus control options.
The control options included detergent limitations, municipal treatment plant
control, nonpoint source control and combinations of tertiary sewage treatment
and nonpoint source control. The results indicated that although site
specific studies should be conducted for any given lake, as a general rule
detergent phosphorus control would be of marginal value. Eighty percent
reductions in municipal treatment plant discharges would reduce average lake
phosphorus control would be of marginal value. Eighty percent reductions in
municipal treatment plant discharges would reduce average lake phosphorus
concentration from 0.084 mg/£ to 0.059 mg/&. A combination of municipal
control and a sixty percent reduction in nonpoint sources would reduce
average lake phosphorus concentration'from 0.084 mg/£ to 0.029 mg/£. It was
found that nonpoint source control was more effective in increasing the
number of lakes with less than 0.025 mg/& of total phosphorus than was an
equivalent level of point source control.
17.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.IDENTIFIERS/OPEN ENDED TERMS C. COSATI Field/Group
Phosphorus
National Eutrophication Survey
Eutrophication
Chlorophyll-a
18. DISTRIBUTION STATEMENT
Unlimited Distribution
19. SECURITY CLASS (This Report)
Unclassified
21. NO. OF PAGES
147 + Appendices
20. SECURITY CLASS (This page)
Unclassified
22. PRICE
EPA Form 2220-1 (Rev. 4-77) PREVIOUS EDITION is OBSOLETE
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