U.S. ENVIRONMENTAL PROTECTION AGENCY
               NATIONAL EUTROPHICATION SURVEY
                        WORKING PAPER SERIES

                                             REPORT
                                              ON
                                         LAKE COLORADO CITY
                                          MITCHELL COUNTY
                                              TEXAS
                                           EPA REGION VI
                                        WORKING PAPER No,
     CORVALLIS ENVIRONMENTAL RESEARCH LABORATORY - CORVALL1S, OREGON
                                 and
    ENVIRONMENTAL MONITORING & SUPPORT LABORATORY - LAS VEGAS, NEVADA
•&G.P.O. 699-440

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                             REPORT
                               ON
                        LAKE COLORADO CITY
                         MITCHELL COUNTY
                              TEXAS
                          EPA REGION VI
                      WORKING PAPER No, 640
WITH THE COOPERATION OF THE
 TEXAS WATER QUALITY BOARD
          AND THE
    TEXAS NATIONAL GUARD
       FEBRUARY/ 1977

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                               CONTENTS
                                                           Page
  Foreward                                                    ii
  List of Texas  Study Reservoirs                              iv
  Lake and  Drainage Area Map                                 vi

  Sections
  I.  Conclusions                                             1
 II.  Lake  and Drainage Basin Characteristics             .     3
III.  Lake  Water Quality Summary                               4
 IV.  Nutrient Loadings                                       9
  V.  Literature Reviewed                                    13
 VI.  Appendices                                             14

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                                 11
                          FOREWORD
    The National Eutrophication Survey was initiated in 1972 in
response to an Administration commitment to investigate the nation-
wide threat of accelerated eutrophication to freshwater lakes and
reservoirs.

OBJECTIVES

    The Survey was designed to develop, in conjunction with state
environmental agencies, information on nutrient sources, concentrations,
and impact on selected freshwater lakes as a basis for formulating
comprehensive and coordinated national, regional, and state management
practices relating to point-source discharge reduction and non-point
source pollution abatement in lake watersheds.

ANALYTIC APPROACH

    The mathematical and statistical procedures selected for the
Survey's eutrophication analysis are based on related concepts that:

        a.  A generalized representation or model relating
    sources, concentrations, and impacts can be constructed.

        b.  By applying measurements of relevant parameters
    associated with lake degradation, the generalized model
    can be transformed into an operational representation of
    a lake, its drainage basin, and related nutrients.

        c.  With such a transformation, an assessment of the
    potential for eutrophication control can be made.

LAKE ANALYSIS

    In this report, the first stage of evaluation of lake and water-
shed data collected from the study Take and its drainage basin is
documented.  The report is formatted to provide state environmental
agencies with specific Information for basin planning [§303(e)], water
quality criteria/standards review [§303(c)], clean lakes [§314(a,b)],
and water quality monitoring [§106 and §305(b)] activities mandated
by the Federal Water Pollution Control Act Amendments of 1972.

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                                m
     Beyond the single lake analysis, broader based correlations
between nutrient concentrations (and loading) and trophic condi-
tion are being made to advance the rationale and data base for
refinement of nutrient water quality criteria for the Nation's
fresh water lakes.  Likewise, multivariate evaluations for the
relationships between land use, nutrient export, and trophic
condition, by lake class or use, are being developed to assist
in the formulation of planning guidelines and policies by EPA
and to augment plans implementation by the states.

ACKNOWLEDGEMENT

     The staff of the National Eutrophication Survey (Office of
Research & Development, U. S. Environmental  Protection Agency)
expresses sincere appreciation to the Texas  Water Quality Board
for professional involvement, to the Texas National Guard for
conducting the tributary sampling phase of the Survey, and to
those Texas wastewater treatment plant operators who voluntarily
provided effluent samples.

     Hugh C.  Yantis, Jr., Executive Director of the Texas Water
Quality Board, and John B. Latchford, Jr., Director, and the staff
of the Field Operations Division provided invaluable lake documen-
tation and counsel during the Survey, reviewed the preliminary
reports, and provided critiques most useful  in the preparation of
this Working Paper series.

     Major General Thomas Bishop, the Adjutant General of Texas,
and Project Officer Colonel William L. Seals, who directed the
volunteer efforts of the Texas National Guardsmen,  are also grate-
fully acknowledged for their assistance to the Survey.

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                                 1v
                  NATIONAL EUTROPHICATION SURVEY
                         STUDY RESERVOIRS
                          State of Texas
NAME
Amistad
Bastrop
Bel ton
Braunig
Brownwood
Buchanan
Caddo

Calaveras
Canyon
Colorado City
Corpus Christi

Diversion
Eagle Mountain
Fort Phantom Hill
Houston
Kemp
Lake O'The Pines
Lavon
Lewisville (Garza-Little Elm)
Livingston
COUNTY
Val Verde
Bastrop
Bell, Coryell
Bexar
Brown
Burnet, Llano
Harrison, Marion, TX;
Caddo Parish, LA
Bexar
Comal
Mitchell
Jim Wells, Live Oak, San
Patricio
Archer, Baylor
Tarrant, Wise
Jones
Harris
Baylor
Camp, Marion, Morris,
Upshur
Collin
Denton
Polk, San Jacinto, Trinity,
Waiker

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Lyndon B. Johnson
Medina
Meredith

0. C. Fisher (San Angelo)
Palestine

Possum Kingdom

Sam Rayburn

Somervilie
E. V. Spence
Stamford
Stillhouse Hollow
Tawakoni
Texoma

Travis
Trinidad
Twin Buttes
White River
Whitney
Wright Patman (Texarkana)
Burnet, Llano
Bandera, Medina
Hutchinson, Moore,
Potter
Tom Green
Anderson, Cherokee,
Henderson, Smith
Palo Pinto, Stephens,
Young
Angelina, Jasper
Nacogdoches, Sabine, San
Augustine
Burleson, Lee, Washington
Coke
Haskell
Bell
Hunt, Rains, Van Zandt
Cooke, Grayson TX; Bryan,
Johnston, Love, Marshall, OK
Burnet, Travis
Henderson
Tom Green
Crosby
Bosque, Hill
Bowie, Cass

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         LAKE  COLORADO CITY
            Tributary Sampling Site
          X Lake Sampling Site
          ^} Drainage Area Boundary
                    <69 Km.
                 T~SsI MI.
                   Sc^le
icno
                                          Wl'OO

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                             LAKE COLORADO CITY



                              STORE! NO. 4810








I.   CONCLUSIONS



    A.  Trophic Condition:



            Survey data indicate that Lake Colorado City i~. eutrophic;



        i.e., well supplied with nutrients and quite productive.  Whether



        nutrient enrichment is beneficial or deleterious depends on the



        actual or potential effect on the uses of the lake.  In this



        regard, no nuisance conditions are known to personnel of the



        Texas Water Quality Board, and there is little or no impairment



        of the designated beneficial uses of this lake.



            Lake Colorado City ranked twentieth in overall trophic quality



        when the 39 Texas reservoirs sampled in 1974 were compared using



        Q combination of six parameters*.  Twenty-two of the water bodies



        had less and two had the same median total and median dissolved



        phosphorus, eight had less and two had the same median inorganic



        nitrogen, 22 had less mean chlorophyll a_, and 28 had greater mean



        Secchi disc transparency.



            Survey limnologists did not observe algal blooms or macrophytes



        in the lake during sampling visits.



    B.  Rate-Limiting Nutrient:



            The algal assay results indicate that nitrogen was limiting at



        the time the sample was taken (10/28/74).



            The lake data indicate nitrogen limitation in March and October



        but phosphorus limitation in May.
  See Appendix A.

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    C.  Nutrient Controllability:
            1.  Point  sources--No known municipal or industrial point
        sources impacted  Lake Colorado City during the sampling year.
            Septic tanks  serving lakeshore dwellings are estimated to have
        contributed 8.3%  of the total phosphorus load to the lake; however,
        a shoreline survey would be needed to determine the actual con-
        tributions of  these sources.
            The phosphorus loading of 0.21 g/m2 measured during the sampling
        year is a little  more than that proposed by Vollenweider  (Vollen-
        weider and Dillon, 1974) as a eutrophic loading (see page 12).
        Regardless of  the applicability of Vollenweider1s eutrophic level
        to Texas reservoirs, the lake is eutrophic, and all phosphorus
        inputs should  be  reduced to the greatest practicable degree.
            2.  Non-point sources—The phosphorus contributions of non-point
        sources, including precipitation, accounted for nearly 92% of the
        total load reaching the lake during the sampling year.  Morgan Creek
        contributed 66.5%, Unnamed Stream B-l contributed 6.8%, and the
        ungaged drainage  area was estimated to have contributed 10.1% of the
        total phosphorus  load.
            The phosphorus export rates of Morgan Creek and Unnamed Stream
        B-l were 1 and 4  kg/km2/yr, respectively (see page 11).   These rates
        are quite low  compared to the rate of a tributary to nearby Lake
        Stamford* (28  kg/km2/yr).


* Working Paper No. 660.

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II.   LAKE AND DRAINAGE BASIN CHARACTERISTICS1
     A.   Lake Morphometry  :
         1.   Surface area:   6.52 kilometers2.
         2.   Mean depth:   6.0 meters.
         3.   Maximum depth:   >8.2 meters.
         4.   Volume:  39.120 x 106 m3.
         5.   Mean hydraulic  retention  time:   3.9  years  (based on  outflow),
     B.   Tributary and Outlet:
         (See Appendix C  for flow data)
         1.   Tributaries  -
                                               Drainage        Mean  flow
             Name                              area (km2)*     (m3/sec)*
             Morgan Creek                          709.7          0.282
             Unnamed Stream  B-l                      26.4          0.011
             Minor tributaries &
              immediate drainage -                  91.4          0.043
                         Totals                     827.5          0.336
         2.   Outlet -
             Morgan Creek                          834.0**        0.321
     C.   Precipitation***:
         1.   Year of sampling:  57.9 centimeters.
         2.   Mean annual:   50.0  centimeters.
 t  Table of metric  conversions—Appendix B.
 tt Latchford,  1974.
 *  For limits of accuracy,  see  Working Paper No.  175,  "...Survey Methods,
   1973-1976".
 ** Includes area of  lake.
 *** See Working Paper  No.  175.

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III.  LAKE WATER QUALITY SUMMARY
      Lake Colorado City was sampled four times during 1974 by means of a
  pontoon-equipped Huey helicopter.  Each time, samples for physical and '
  chemical parameters were collected from two stations on the lake and from
  a number of depths at each station (see map, page vi).  During each visit,
  a single depth-integrated (4.6 m or near bottom to surface) sample was
  composited from the stations for phytoplankton identification and enumer-
  ation; and during the October visit, a single 18.9-liter depth-integrated
  sample was composited for algal assays.  Also each time, a depth-integrated
  sample was collected from each of the stations for chlorophyll a_ analysis.
  The maximum depths sampled were 8.2 meters at station 1 and 4.9 meters at
  station 2.
      The sampling results are presented in full in Appendix D and are
  summarized in the following table (the August nutrient samples were not
  preserved properly and were not analyzed).

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PARAMETER

TEMP (C)

DISS OXY (MG/L)

CNDCTVY (MCROMO)

PH (STAND UNITS)

TOT ALK (MG/L)

TOT P (MG/L)

ORTHO P (MG/L)

N02»N03 (MG/L)

AMMONIA (MG/L)

KJEL N  (MG/L)

INORG N (MG/L)

TOTAL N (MG/L)

CHLRPYL A  

SECCHI  (METERS)
                             A. SUMMARY OF PHYSICAL  AND


                             1ST SAMPLING  (  3/ 4/74)

                                   2 SITES
     RANGE

 14.2  -  21.5

  6.8  -   8.0

1396.  - 1640.

  8.2  -   8.5

 152.  -  164.

0.021  - 0.046

0.009  - 0.019

0.020  - 0.070

0.030  - 0.090

0.600  - 0.900

0.050  - 0.130

0.620  - 0.940

  6.<.  -   6.5

  0.8  -   1.1
                                  CHEMICAL  CHARACTERISTICS  FOH LAKE COLORADO CITY
                                   STCRET CODE 4310

                                              2ND SAMPLING  (  5/15/74)

                                                   2  SITES
3RD SAMPLING ( 8/ 6/74)

      2 SITES
MEAN
18.1
7.5
1543.
8.4
161.
0*026
0.013
0.040
0.046
0.714
0.086
0.754
6.4
0.9
MEDIAN
18.6
7.8
1545.
8.4
163. •
0.023
0.013
0.04U
0.030
0.700
0.080
0.730
6.4
0.9
RANGE
25.9
6.0
2049.
7.8
138.
0.035
0.006
0.030
0.040
0.700
0.070
0.780
7.3
0.4
- 29.2
7.0
- 2212.
8.3
- 148.
- 0.055
- 0.009
- 0.190
- 0.160
- 1.300
- 0.350
- 1.390
7. to
0.4
MEAN
27.8
6.*
2138.
8.2
142.
0.044
0.008
0.093
0.076
0.886
0.169
0.979
7.4
0.4
MEDIAN
27.5
6.2
2144.
8.3
141.
0.042
0.008
0.080
0.070
0.800
0.150
0.900
7.4
0.4
RANGE MEAN MEDIAN
27.8 - 30.5 29.3 29.2
4.8 - 6.2 5.7 5.8
2490. - 2584. 2546. 2546.
8.1 - 8.9 8.3 8.2
*..... ..*..**....*.....«.*.•«
••• 	 .*...............
...... -..*......*............
e»«O»» _««««««..»..««»»«•«»«.«
..,»<,<, .......................
«*««»» _ 
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                             A. SUMMARY OF PHYSICAL AND CHEMICAL CHARACTERISTICS FOR LAKE COLORADO cm
                                                         STOrtET CODE 4810

                             4TH SAMPLING (10/28/74)
PARAMETER

TEMP (C)

OISS OXY (MG/LI

CNOCTVY (MCSOMO)

PH (STAND UNITS)

TOT ALK (MG/L)

TOT P (MG/L)

ORTHO P (MG/L>

N02 + N03 (MG/L)

AMMONIA (MG/D

KJEL N  (MG/L)

INORG N (MG/D

TOTAL N (MG/L)

CHLRPYL A (UG/D

SECCHI  (METERS)
     SANGE

 21.0  -  23.1

  6.4  -

1166.  - 1517.

  8.4  -

 109.  -  118.

0.042  - 0.074

0.012  - 0.026

0.020  - 0.060

0.030  - 0.040

0.600  - 0.800

0.050  - 0.100

0.660  - 0.820

 16.2  -  20.5

  0.5  -
? SITES
MEAN
1
4

5
1.
'4
!6
iO
•0
10
'0
!0
5
7
21.8
6.8
1353.
8.4
114.
0.055
0.018
0.039
0.033
0.686
0.071
0.724
18.3
0.6
MEDIAN
21.5
6.8
1453.
8.4
115.
0.046
0.017
0.030
0.030
0.700
0.060
0.720
10.3
0.6

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B.  Biological characteristics:
    1.  Phytoplankton -

        Sampling
        Date

        03/04/74
        05/15/74
        08/06/74
        10/28/74
Dominant
Genera
1.
2.
3.
4.
5.
1.
2.
3.
4.
5.
1.
2.
3.
4.
5.
1.
2.
3.
4.
5.
Diploneis sp.
Oscillatoria sp.
Flagellates
Synedra sp.
Dactyl ococcops is sp,
Other genera
Total
Tetraedron sp.
Chroomonas sp.
Diploneis sp.
Scenedesmus sp.
Oocystis sp.
Other genera
Total
Oscillatoria sp.
Lyngbya sp.
Nitzschia s£.
Oocystis sj^.
Cryptomonas sp.
Other genera
Total
Oscillatoris sp.
Nitzschia SJD.
Diploneis sp.
Tetraedron sp.
Lyngbya sp.
Other genera
Total
Algal Units
per ml	
   2,
   2
   140
   014
   797
   545
   336
 1.972

 7,804

 3,283
 1,082
   830
   722
   721
 3.102

 9,740

10,277
 5,755
 1,953
   445
   445
 2,501

21,376

 8,779
 2,287
 2,164
 1,266
 1,255
 3,605

19,356

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    2.  Chlorophyll a -
Sampling
Date
03/04/74
05/15/74
08/06/74
10/28/74
Station
Number
1
2
1
2
1
2
1
2
                                                         Chlorophyll a
                                                         (yg/D
                                                              6.5
                                                              6.4
                                                              7.6
                                                              7.3
                                                             17.5
                                                             19.4
                                                             16.2
                                                             20.5
C.  Limiting Nutrient Study:
    1.  Autoclaved, filtered, and nutrient spiked -
                         Ortho P
                         Cone, (mg/1)
Inorganic N
Cone, (mg/1)
Maximum yield
(mg/1-dry wt.)
0.029
0.079
0.079
0.029
0.096
0.096
1.096
1.096
4.5
4.4
28.2
8.4
    Spike (mg/1)
    Control
    0.050 P
    0.050 P + 1.0
    1.0 N
2.  Discussion -
        The control yield of the assay alga, Selenastrum capri-
    cornutum, indicates that the potential primary productivity
    of Lake Colorado City was moderately high when the sample was
    collected (10/28/74).  There was no significant change in yield
    with the addition of orthophosphorus, but nitrogen added alone
    produced a yield significantly greater than that of the control.
    These results indicate that nitrogen was the limiting nutrient.
        The lake data support the assay findings.  The mean inorganic
    nitrogen/orthophosphorus ratio was 4/1 in October and was 7/1 in
    March, indicating nitrogen limitation.  However, the N/P ratio
    in May was 21/1, and phosphorus limitation would be expected.

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IV.   NUTRIENT LOADINGS
     (See Appendix E for data)
     For the determination of nutrient loadings, the Texas National
 Guard collected monthly near-surface grab samples from each of the
 tributary sites indicated on the map (page vi), except for the high
 runoff months of April  and May when two samples were collected.
 Sampling was begun in September, 1974,  and was completed in August,
 1975.
     Through an interagency agreement, stream flow estimates for the
 year of sampling and a "normalized" or average year were provided by
 the Texas District Office of the U.S. Geological Survey for the
 tributary sites nearest the lake.
     In this report, nutrient loads for sampled tributaries were
 calculated using mean annual concentrations and mean annual flows.
 Nutrient loads for unsampled "minor tributaries and immediate
 drainage" ("ZZ" of U.S.G.S.) were estimated using the mean concentra-
 tions in Morgan Creek at station A-2 and the mean annual ZZ flow.
     No known municipal  or industrial point sources impacted Lake
 Colorado City during the sampling year.

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                                    10
    A.  Waste Sources:
        1.  Known municipal - None
        2.  Known industrial - None
    B.  Annual Total Phosphorus Loading - Average Year:
        1.  Inputs -
                                              kg P/           % of
            Source                            yr              total
            a.  Tributaries (non-point load) -
                Morgan Creek                    925            66.5
                Unnamed Stream B-l               95             6.8
            b.  Minor tributaries & immediate
                 drainage  (non-point load) -    140            10.1
            c.  Known municipal STP's - None
            d.  Septic tanks* -                 115             8.3
            e.  Known industrial - None
            f.  Direct precipitatio:o** -        115             8.3
                        Total                 1,390           100.0
        2.  Outputs -
            Lake outlet -  Morgan Creek        1,385
        3.  Net annual P accumulation - 5 kg.
* Estimate based on 400 lakeshore dwellings  (Wyatt, 1976); see Working  Paper
  No. 175.
** See Working Paper No. 175.

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                                    11
    C.  Annual Total Nitrogen Loading - Average Year:
        1.  Inputs -
                                              kg N/           % of
            Source                            y_r	           total
            a.  Tributaries  (non-point load) -
                Morgan Creek                  12,325           47.5
                Unnamed Stream B-l               475            1.8
            b.  Minor tributaries & immediate
                 drainage  (non-point load) -   1,880            7.2
            c.  Known municipal STP's - None
            d.  Septic tanks* -                4,265           16.4
            e.  Known industrial - None
            f.  Direct precipitation** -       7,040           27.1
                        Total                 25,985          100.0
        2.  Outputs -
            Lake outlet - Morgan Creek        16,620
        3.  Net annual N accumulation - 9,365 kg.
    D.  Non-point Nutrient Export by Subdrainage Area:
        Tributary                             kg P/km2/yr     kg N/km2/yr
        Morgan Creek                              1              17
        Unnamed Stream B-1                        4              18
* Estimate based on 400 lakeshore dwellings (Wyatt, 1976); see Working Paper
  No. 175.
** See Working Paper No. 175.

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                                12
E.  Yearly Loads:
        In the following table, the existing phosphorus loadings
    are compared to those proposed by Vollenweider (Vollenweider
    and Dillon, 1974).  Essentially, his "dangerous" loading is
    one at which the receiving water would become eutrophic or
    remain eutrophic; his "permissible" loading is that which
    would result in the receiving water remaining oligotrophic
    or becoming oligotrophic if morphometry permitted.  A meso-
    trophic loading would be considered one between "dangerous"
    and "permissible".
        Note that Vollenweider's model may not be applicable to
    water bodies with short hydraulic retention times.
                              Total Phosphorus       Total Nitrogen
    	Total   Accumulated    Total   Accumulated
    grams/m2/yr             0.21      < 0.01        4.0        1.4

    Vollenweider phosphorus loadings
     (g/m2/yr) based on mean depth and mean
     hydraulic retention time of Lake Colorado City:
        "Dangerous"  (eutrophic loading)              0.20
        "Permissible"  (oligotrophic loading)         0.10

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                                    13
V.  LITERATURE REVIEWED

    Latchford, John B., Jr., 1974.  Personal communication  (lake morphornetry),
        TX Water Qual. Bel., Austin.

    Vollenweider, R. A., and P. J. Dillon,  1974.  The application of
        the phosphorus loading concept to eutrophication  research.
        Natl. Res. Council of Canada Publ.  No.  13690, Canada Centre
        for Inland Waters, Burlington, Ontario.

    Wyatt, Linda B., 1976.  Personal communication  (estimate of lakeshore
        dwellings).  TX Water Qual. Bd., Austin.

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VI.   APPENDICES
                                  14
                                  APPENDIX A
                                 LAKE RANKINGS

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LAKE DATA TO BE USED IN RANKINGS
LAKE
CODE  LAKE NAME

4801  AMISTAD LAKE

4802  8ASTROP LAKE

4603  8ELTON RESERVOIR

4804  BRAUNIG LAKE

4805  BROWNWOOD LAKE

4806  LAKE BUCHANAN

4807  CAODO LAKE

4808  CALAVERAS LAKE

4809  CANYON RESERVOIR

4810  LAKE COLORADO CITY

4811  CORPUS CRISTI LAKE

4812  DIVERSION LAKE

4813  EAGLE MOUNTAIN LAKE

4814  FT PHANTOM HILL LAKE

4815  GARZA LITTLE ELM RESERVO

4816  KEMP LAKE

4817  HOUSTON LAKE

4818  LAKE OF THE PINES

4819  LAVON RESERVOIR

4820  LIVINGSTON LAKE

4821  LYNDON B JOHNSON LAKE

4822  MEDINA LAKE

4823 , LAKE MEREDITH

4824  PALESTINE LAKE

4825  POSSUM KINGDOM RESERVOIR

4826  SAN ANGELO RESERVOIR

4827  SAM RAYBURN RESERVOIR

4828  E V SPENCE RESERVOIR
MEDIAN
TOTAL P
0.013
0.02?
0.016
0.134
0.027
0.036
0.055
0.038
0.010
0.042
0.113
0.025
0.024
0.060
0.045
0.023
0.097
0.031
0.063
0.196
0.042
0.010
0.021
0.031
0.023
0.093
0.029
0.036
MEDIAN
INOSG N
0.500
0.090
0.165
0.150
0.100
0.250
0.070
0.060
0.450
0.090
0.130
0.080
0.070
0.105
0.380
O.UO
0.260
0.090
0.180
0.555
0.420
0.600
0.070
0.180
0.070
0.140
0.150
0.080
500-
MEAN SEC
371.474
419.917
378.312
461.625
470.375
437.625
463.333
461.667
384.812
473.625
475.187
470.111
469.625
474.909
475.782
455.000
486.187
440.000
485,333
465.469
456.500
403.562
439.312
442.625
419.045
481.000
439.458
462.583
MEAN
CHLOWA
2.0O
12.392
8.025
22.762
4.887
8.606
14.808
22.500
2.500
12.675
19.756
15.867
5.662
6.317
14.156
10.217
16.650
12.919
5.400
16.112
8.100
12.944
3.037
10.619
9.495
24.675
6.267
11.775
15-
MIN 00
14.900
15.000
15.000
14.800
14.400
15.000
11.400
13.000
14.800
10.200
14.000
9.000
11.000
9.800
14.600
10.400
12.400
15.000
8.800
15.000
14.900
15.000
14.900
14.800
15.000
10.200
15.000
15.000
MEDIAN
DISS OUTHO P
0.009
0.007
0.007
0.062
0.007
0.012
O.OlJ
0.007
0.006
0.012
0.050
0.009
0.008
0.022
0.018
0.007
0.036
0.011
0.018
0.128
0.013
0.004
0.009
0.010
0.009
0.011
0.009
0.008

-------
LAKE DATA TO BE USED IN RANKINGS

LAKE
CODE  LAKE NAME

4829  SOMERVILLE LAKE

4830  STAMFORD LAKE

4631  STILLHOUSE HOLLO* RESEKV

4832  TAWAKOM LAKE

4833  TEXARKANA LAKE

4834  TEXOMA LAKE

4835  TRAVIS LAKE

4836  TRINIDAD

4837  TWIN BUTTES RESERVOIR

4838  WHITE RIVER RESERVOIR

4839  WHITNEY LAKE
MEDIAN
TOTAL P
0.053
0.073
O.Olh
0.046
0.106
0.042
0.018
0.389
0.029
0.020
0.028
MEDIAN
1NOHG N
0.115
O.C60
0.160
0.100
0.120
0.160
0.250
0.110
0.250
0.110
0.120
500-
MEAN SEC
473.833
482.714
406.250
466.417
478.500
451.321
389.913
479.500
454.917
434.500
430.500
MEAi.
CHLORA
24.491
18.457
3.917
18.246
19.119
12.493
5.595
24.300
8.708
4.333
6.912
MIN DO
13.000
10.600
15.000
13.200
12.400
15.000
15.000
10.000
14.800
15.000
15.000
MEDIAN
DISS O^TriO
0.013
0.012
0.010
0.013
0.030
0.018
0.007
0.240
0.009
0.009
0.008

-------
PERCENT OF LAKES WITH HIGHER VALUES (NUMBER of- LAKES «ifr? «IGUEK VALUES)
LAKE
CODE  LAKE NAME
4801  AMISTAO LAKE
4802  8ASTROD LAKE
4803  8ELTON RESERVOIR
4804  BRAUNIG LAKE
4805  BROrtNWOOD LAKE
4806  LAKE BUCHANAN
4807  CADOO LAKE
4808  CALAVERAS LAKE
4809  CANYON RESERVOIR
4810  LAKE COLORADO CITY
4811  CORPUS CRIST! LAKE
4812  DIVERSION LAKE
4813  EAGLE MOUNTAIN LAKE
4814  FT PHANTOM HILL LAKE
4815  GARZA LITTLE ELM RESERVO
4816  KEMP LAKE
4817  HOUSTON LAKE
4818  LAKE OF THE PINES
4819  LAVON RESERVOIR
4820  LIVINGSTON LAKE
4821  LYNDON 8 JOHNSON LAKE
4822  MEDINA LAKE
4823  LAKE MEREDITH
4824  PALESTINE LAKE
4825  POSSUM KINGDOM RESERVOIR
4826  SAN ANGELO RESERVOIR
4827  SAM RAYBURN RESERVOIR
4828  E V SPENCE RESERVOIR
MEDIAN
TOTAL P
95
79
92
5
66
47
26
45
99
39
8
68
71
24
34
76
16
54
21
3
39
99
82
54
74
13
59
50
( 36)
( 30)
( 35)
( 2)
( 25)
( 18)
( 10)
( 17)
( 37)
( 14)
( 3)
( 26)
( 27)
( 9)
( 13)
( 29)
( 6)
( 20)
( 8)
( 1)
( 14)
( 37)
< 31)
< 20)
( 28)
( 5)
( 22)
t 19)
MEDIAN
INO^G N
5
76
26
42
70
21
91
100
8
76
47
83
91
66
13
61
16
76
29
3
11
0
91
32
91
45
39
83
( 2)
( 28)
( 10)
( 16)
( 26)
( 7)
( 33)
( 38)
( 3)
( 28)
( 18)
( 31)
( 33)
( 25)
( 5)
( 22)
( 6)
( 28)
( ID
( 1)
( 4)
( 0)
( 33)
< 12)
( 33)
( 17)
( 15)
( 31)
500-
MEAN SEC
100
82
97
50
29
74
42
47
95
26
18
32
34
21
16
55
0
66
3
39
53
89
71
63
84
8
68
45
( 38)
( 31)
( 37)
( 19)
( 11)
( 28)
( 16)
( 18)
( 36)
( 10)
( 7)
( 12)
( 13)
( 8)
( 6)
( 21)
( 0)
( 25)
< 1)
( 15)
< 20)
< 34)
< 27)
( 24)
( 32)
( 3)
( 26)
( 17)
MEAN
CHLOriA
100
47
68
8
87
63
32
11
97
42
13
29
79
74
34
55
24
39
84
26
66
37
95
53
53
0
76
50
( 38)
( 18)
( 26)
( 3)
( 33)
( 24)
( 12)
( 4)
( 37)
( 16)
( 5)
( ID
( 30)
( 28)
( 13)
( 21)
( 9)
( 15)
( 32)
( 10)
( 25)
( 14)
( 36)
( 20)
( 22)
( 0)
( 29)
( ISi)
15-
MIN UO
39
17
17
49
58
17
76
67
49
88
61
97
79
95
55
84
72
17
100
17
39
17
39
49
17
88
17
17
( 14)
( 0)
( 0)
t 17)
( 22)
< 0)
( 29)
( 25)
( 17)
( 33)
( 23)
( 37)
( 30)
( 36)
( 21)
( 32)
( 27)
( 0)
( 38)
( 0)
( 14)
( 0)
( 14)
( 17)
( 0)
( 33)
( 0)
( 0)
MEDIAN
oiss OKTHO P
63
92
84
5
84
39
30
92
97
39
a
63
76
16
21
.92
11
46
21
'3
30
100
63
51
63
46
63
76
( 21)
( 34)
( 31)
( 2)
( 31)
( 14)
( 10)
( 34)
( 37)
( 14)
( 3)
( 21)
( 28)
( 6)
( 7)
( 34)
( 4)
( 17)
( 7)
( 1)
( 10)
( 38)
< 21)
( 19)
( 21)
( 17)
( 21)
( 28)
INDEX
NO
40
-------
PERCENT or LAKES WITH HIGHER VALUES (NUMBER  OF  LAKES  *ITH  HIGHER  VALUES)

LAKE
coot  LAKE NAME

4829  SOMERVILLE LAKE

4830  STAMFORD LAKE

4831  STILLHOUSE HOLLOW RESErtV

4832  TAWAKONI LAKE

4833  TEXARKANA LAKE

4834  TEXOMA LAKE

4835  TRAVIS LAKE

4836  TRINIDAD

4837  TWIN BUTTES RESERVOIR

4838  WHITE RIVER RESERVOIR

4839  WHITNEr LAKE
MEDIAN
TOTAL P
29 (
18 (
88 (
32 (
11 <
39 (
88 <
0 (
59 (
84 (
63 <
11)
7)
33)
12)
4)
14)
33)
0)
22)
32)
24)
MEDIAN
INORG N
55
V7
37
70
51
34
21
61
21
61
51
( 21)
'. 37)
( 14)
( 26)
( 19)
( 13)
( 7)
( 22)
( 7)
< 22)
( 19)
500-
MEAN SEC
24
5
87
37
13
61
92
11
58
76
79
( 9)
( 2)
( 33)
( 14)
( 5)
( 23)
( 35)
( 4)
( 22)
( 29)
< 30)
MEAN
CHLO^A
3
18
92
21
16
45
82
5
61
89
71
( 1)
( 7)
( 35)
( 8)
( 6)
( 17)
( 3D
( 2)
( 23)
( 34)
( 27)
15-
MIN oo
67
82
17
63
72
17
17
92
49
17
17
( 25)
( 3D
( 0)
( 24)
< 27)
( 0)
( 0)
( 35)
< 17)
( 0)
( 0)
MEDIAN
DISS 0*THO P
30 I
39 (
51 (
30 (
13 (
21 (
84 (
0 (
63 (
63 (
76 (
10)
14)
19)
10)
5)
7)
31)
0)
21)
21)
28)
INDEX
NO
20rt
259
372
2i3
176
217
J84
169
311
390
357

-------
LAKES RANKED BY INDEX N05,




RANK  LAKE CODE  LAKE NAME               INDEX NO






   1  4809       CANYON RESERVOIR           445




   2  4823       LAKE MEREDITH              441




   3  4813       EAGLE MOUNTAIN LAKE        430




   4  4816       KEMP LAKE                  423




   S  4801       AMISTAO LAKE               402



   6  4805       BRO«N«OOD LAKE             394




   7  4802       BASTROP LAKE               393




   8  4838       WHITE RIVER RESERVOIR      390



   9  4825       POSSUM KINGDOM RESERVOIR   387



  10  4835       TRAVIS LAKE                384




  11  4803       BELTON RESERVOIR           384




  12  4831       STILLHOUSE HOLLOW RESERV   372



  13  4812       DIVERSION LAKE             372



  14  4808       CALAVERAS LAKE             362



  15  4839       WHITNEY LAKE               357




  16  4822       MEDINA LAKE                342



  17  4827       SAM RAYBURN RESERVOIR      322



  18  4828       E V SPENCE RESERVOIR       321



  19  4837       TWIN 8UTTES RESERVOIR      311



  20  4810       LAKE COLORADO CITY         310




  21  4824       PALESTINE LAKE             302



  22  4818       LAKE OF THE PINES          298



  23  4807       CADDO LAKE                 297




  24  4814       FT PHANTOM HILL LAKE       296



  25  4806       LAKE BUCHANAN              261




  26  4830       STAMFORD LAKE              259



  27  4819       LAVON RESERVOIR            258




  28  4832       TArfAKONI LAKE              253

-------
LAKES RANKED BY INDEX NOS.
RANK  LAKE CODE  LAKE NAME               INDEX NO
  29  4821       LYNDON B JOHNSON LAKE      238
  30  4834       TEXOMA LAKE                217
  31  4829       SOMEKVILLE LAKE            208
  32  4826       SAN ANGELO RESERVOIR       200
  33  4833       TEXAKKANA LAKE             176
  34  4815       GARZA LITTLE ELM RESERVO   173
  35  4836       TRINIDAD                   169
  36  4804       BRAUNIG LAKE               159
  37  4811       CORPUS CRIST! LAKE         155
  38  4817       HOUSTON LAKE               139
  39  4820       LIVINGSTON LAKE             91

-------
    APPENDIX B





CONVERSION FACTORS

-------
                CONVERSION FACTORS

Hectares x 2.471 = acres
Kilometers x 0.6214 = miles
Meters x 3.281 = feet
                         -4
Cubic meters x 8.107 x 10   = acre/feet
Square kilometers x 0.3861 = square miles
Cubic meters/sec x 35.315 = cubic feet/sec
Centimeters x 0.3937 = inches
Kilograms x 2.205 = pounds
Kilograms/square kilometer x 5.711 = Ibs/square mile

-------
    APPENDIX C
TRIBUTARY FLOW DATA

-------
                                               FLO,; ii\FDr
-------
                                                 FLO*
                                                                                                   03/12/76
LA
-------
        APPENDIX D





PHYSICAL and CHEMICAL DATA

-------
SYORET RET*levAL DATE 70/02/11
                                                                  481001
                                                                 32  19  19.0  100 55 04.0
                                                                 LAKE COLORADO CITY
                                                                 48335   TEXAS
  DATE   TIME DEPTH
  FROM    OF
   TO    DAY  FEET
 74/03/04  10
          10
          10
          10
 74/05/15  12
          12
          12
          12
 74/08/06  10
          10
          10
          10
 74/10/28  16
          16
          16
          16
20 0000
20 0005
20 0015
20 0027
10 0000
10 0005
10 0015
10 0027
00 0000
00 0005
00 0015
00 0025
00 0000
00 0005
00 0015
00 0027
 00010
WATER
 TEMP
 CENT

   20.4
   16.9
   16.5
   14.2
   29.2
   28.9
   28.1
   25.9
   30.4
   30.5
   29.8
   29.2
   23.1
   22.9
   21.7
   21.5
11EFALES
3
00300 '00077 00094
00 TRANSP CNDUCTVY
SECCHI FIELD
MG/L INCHES MICROMMO

8.0
8.0
7.0
7 ft
* • v
60
• v
6.2
5.6
5.8
5.4
4.8
^ • O
7.4
7.0
*t f>
O. V
6.4
42 1630
1545
1474
1396
14 2212
2155
2049
40 2578
2584
2550
2529
26 1517
1478
1475
1453
00400 00410
PH T ALK
CAC03
SU MG/L
8.50
8.50
8.40
8.20
8.30
8.30
8.10
7.80
8.10
8.20
8.20
8.20
8.52
8.50
8.47
8.42
152
161
163
162
142
141
141
148




118
117
118
115
2111202
0031 FEET DEPTH
00610 00625 00630 00671
NH3-N TOT KJEL N02&N03 PHOS-DIS
TOTAL N N-TOTAL ORTHO
MG/L MG/L MG/L MG/L P
0.040
0.030
0.030
0.090
0.040
0.060
0.070
0.160




0.040
0.030
0.030
0.030
0.900
0.600
0.600
0.800
1.000
0.800
0.700
0.800




0.700
0.800
0.700
0.700
0.040
0.020
0.070
0.040
0.030
0.080
o.oao
0.190




0.020
0.020
0.020
0.030
0.016
0.010
0.013
0.013
0.006
0.006
0.007
0.009




0.017
0.015
0.014
0.012

DATE
FROM
TO
74/03/04



74/05/15



74/08/06

74/10/28




TIME DEPTH
OF
DAY FEET
10 20 0000
10 20 0005
10 20 0015
10 20 0027
12 10 0000
12 10 0005
12 10 0015
12 10 0027
10 00 0000
10 00 0009
16 00 0000
16 00 OOOS
16 00 0015
16 00 0027
00665
PHOS-TOT
MG/L P
0.022
0.021
0.022
0.025
0.039
0.036
0.035
0.052


0.046
0.042
0.044
0.042
32217
CHLRPHYL
A
UG/L
6.5



7.6



17.5

16.2



00031
INCDT LT
REMN1NG
PERCENT








In
.0
Ifi
.0



-------
STOnET RETRIEVAL DATE 76/02/11
                                                                  4310U2
                                                                 32 20 J8.0  100 55  51.0
                                                                 LAKE COLORED CITY
                                                                 4633S   TEXAS
DATE
FROM
TO
74/03/04


74/05/15


74/08/06


74/10/28



DATE
FROM
TO
74/03/04


74/05/15


74/08/06
74/10/28


TIME DEPTH
OF
DA* FEET
11 15 0000
11 15 0005
11 15 0016
11 55 0000
11 55 0005
11 55 0012
10 20 0000
10 20 0005
10 20 0012
IS 35 0000
15 35 0005
15 35 0016

TIME DEPTH
OF
DAY FEET
11 15 0000
11 15 0005
11 15 0016
11 55 0000
11 55 0005
11 55 0012
10 20 0000
15 35 0000
15 35 0005
15 35 0016
00010
WATER
TEMP
CENT
21.5
18.6
16.5
27.5
27.5
27.3
28.8
26.8
27. d
21.0
21.0
21.0
00665
PHOS-TOT

MG/L P
0.025
0.023
0.040
0.055
0.04£
0.0 SO

0.07^.
O.OTi
O.Ob?
00300
00

MG/L

7.8
6.8

6.6
6.2
6.2
6.0
6.0
6.8
6.8
6.8
32217
CHLRPHYL
A
UG/L
6.4


7.3


19.4
20.5


00077
TRANSP
SECChI
INCHES
30


14


24


21


00031
INCDT LT
REMNlNG
PERCENT










00094
CUDUCTVY
FIELD
MICSOMHO
1640
1605
1514
2145
2143
2126
2546
2545
2490
1169
1168
1210














llEPAuES
3
00400 00410
PH T ALK

SU
8.40
8.40
8.3C
8.30
8.30
8.20
6.40
8.40
8.90
8.39
8.38
b.37














CAC03
MG/L
163
164
164
138
139
146



111
109
110














2111202
0020 FEET DEPTH
00610 00625 00630
NH3-N TOT KJEL N02fcN03
TOTAL
MG/L
0.030
0.030
0.070
0.070
0.060
0.070



0.030
0.030
0.040














N
MG/L
0.700
0.700
0.700
1.300
0.800
0.800



0.700
0.600
0.600














N-TOTAL
MG/L
0.030
0.030
0.050
0.090
0.080
0.100



0.060
0.060
0.060














00671
PHOS-UIS
OtfTHO
MG/L P
0.009
0.011
0.019
0.009
0.008
0.009



0.026
0.022
0.023















-------
  APPENDIX E
TRIBUTARY DATA

-------
STORE! RETRIEVAL DATE 76/03/1W
  DATE   TIME DEPTH N02&N03
  FROM    OF
   TO    DAY  FEET
74/09/08
74/10/08
74/11/08
74/12/10
75/01/09
75/02/10
75/03/10
75/04/03
75/04/18
75/05/07
75/05/27
75/06/20
75/07/18
75/08/19
17 05
13 40
13 45
13 00
14 ?5
11 00
11 00
09 30
12 30
14 45
14 25
11 30
11 45
15 10
                                                                  4810A1
                                                                 32 18 55.0 100 55 05.0 4
                                                                 MORGAN WEEK
                                                                 48091   7.5 L« COLO CITY
                                                                 0/l_ArvE COLORADO CITY
                                                                 TX HrfY Ib3 .2 fl DOWNSTREAM FROM DAM
                                                                 11EPALES             2111204
                                                                  0000 FEET  DEPTh  CLASS 00
0630
C.N03
OTAL
G/L
0.040
0.056
0.049
0.104
0.112
0.160
0.020
0.020
0.035
O.OlU
0.005
0.005
0.015
0.010
00625
TOT KJEL
N
MG/L
3.300
1.800
1.400
1.000
1.000
1.200
1.050
0.650
1.800
1.700
1.950
2.200
2.300
1.000
00610
NH3-N
TOTAL
MG/L
0.055
0.035
0.070
0.096
0.152
0.216
0.015
0.025
0.040
0.035
0.020
0.035
0.035
0.025
00671
PriOS-OIS
ORTHO
MG/L P
0.040
0.035
0.010
0.008
0.005K
0.016
0.015
0.010
0.025
0.030
0.045
0.060
0.030
0.025
00665
PHOS-TOT

MG/L P
0.430
0.150
0.060
0.040
0.040
0.030
0.070
0.080
0.140
0.110
0.200
0.240
0.210
0.120
 K VALUE KNOWN TO BE
 LESS THAN INDICATED

-------
STORE! RETRIEVAL DATE 7t,/03/10
  DATE   TIME DEPTH
  FROM    OF
   TO    DAY  FEET
74/10/08
74/11/08
74/12/10
75/01/09
75/02/10
75/03/10
75/04/03
75/04/18
75/05/07
75/05/27
75/06/20
75/07/18
75/08/19
13
14
13
14
11
11
09
12
15
14
11
17
15
55
15
15
45
25
15
45
45
00
45
45
00
30
                                                                  4810A2
                                                                 32 23 00.0 100 58 45.0 4
                                                                 MORGAN CHEt*
                                                                 43      7.5 CEOAR dENu
                                                                 T/LA*E COLORADO CITY
                                                                 UNIMPKOVED «0 XING 4 MI NE OF
                                                                 11EPALES             2111204
                                                                  0000 FEET  DEPTH  CLASS 00
0630
^N03
OTAL
IG/L
0.296
0.168
o.ooa
0.168
0.008
0.040
0.010
0.420
0.440
0.280
0.045
0.130
0.02S
00625
TOT KJEL
N
MG/L
1.200
1.400
0.900
1.200
1.100
1.250
1.000
i.eoo
1.700
1.150
1.100
1.100
1.080
00610
NH3-N
TOTAL
MG/L
0.035
0.025
0.032
0.024
0.032
0.010
0.035
0.050
0.035
0.070
0.035
0.055
0.025
00671
PHOS-OIS
ORTHO
MG/L P
0.015
0.040
0.024
0.005K
0.024
0.015
0.010
0.015
0.015
0.025
0.020
0.015
0.120
00665
DHOS-TOT

MG/L P
0.100
0.120
0.080
0.070
0.050
0.080
0.050
0.060
0.060
0.160
0.110
0.130
0.285
 K VALUE KNOWN TO BE
 LESS THAN INDICATED

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STORE! rtETfiiEVAL DATE 7fc/0i/10
  DATE   TIME DEPTH N02&N03
  FROM    OF
   TO    DAY  FEET

74/11/08 13 30
75/05/27 14 10
75/08/19 15 00
                                                                  4810B1
                                                                 32 21 50.0 100 58 20.0 4
                                                                 UNNAMED STficAM  .
                                                                 48      7.5 LK COLO CITY
                                                                 T/LAKE COLORADO CITY
                                                                 SEC rtO BRDG 2.5 MI E OF KEST8ROOK
                                                                 11EPALES             2111204
                                                                  0000 FEET  DEPTH  CLASS 00
0630
C.N03
OT.AL
iG/L
0.056
0.010
0.090
00625
TOT KJEL
N
MG/L
1.500
1.600
0.850
00610
NH3-N
TOTAL
MG/L
0,065
0.025
0.025
00671
PHOS-01S
ORTHO
MG/L P
0.140
0.070
0.170
00665
PHOS-TOT

MG/L P
0.230
0.250
0.340

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