U.S. ENVIRONMENTAL PROTECTION AGENCY
               NATIONAL EUTROPHICATION SURVEY
                         WORKING PAPER SERIES
                                               REPORT
                                                 ON
                                         BRANCHED OAK RESERVOIR
                                           LANCASTER COIMTY
                                              NEBRASKA
                                            EPA REGION VII
                                         WORKING PAPER No, 554
     CORVALLIS ENVIRONMENTAL RESEARCH LABORATORY - CORVALLIS, OREGON
                                  and
    ENVIRONMENTAL MONITORING & SUPPORT LABORATORY - LAS VEGAS, NEVADA
•&G.V.O. 699-440

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                                     REPORT
                                       ON
                             BRANCHED OAK ESERVDIR
                                LANCASTER COIMTY
                                    NEBRASKA
                                 EPA REGION VII
                             WORKING PAPER No, 554
        WITH THE COOPERATION OF THE
NEBRASKA DEPARTMENT OF ENVIRONMENTAL CONTROL
                  AND THE
          NEBRASKA NATIONAL GUARD
                AUGUST, 1976

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                                   CONTENTS
                                                               Page
  Foreword                                                      ii
  List of Nebraska Study Reservoirs                             iv
  Lake and Drainage Area Map           .                          v

  Sections
  I.   Conclusions                                                1
 II.   Lake and Drainage Basin Characteristics                    3
III.   Lake Water Quality Summary                                 4
 IV.   Nutrient Loadings                                          8
  V.   Literature Reviewed                                       12
 VI.   Appendices                                                13

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                          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 lake 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)L 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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                                 Ill
    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
freshwater 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.

ACKNOWLEDGMENT

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

    The staff of the Water Pollution Control Division, Department
of Environmental Control, provided invaluable lake documentation
and counsel during the Survey, reviewed the preliminary reports,
and provided critiques most useful in the preparation of this Working
Paper series.

    Major General Francis L. Winner, the Adjutant General of Nebraska,
and Project Officer Colonel Burl M. Johnson, who directed the volun-
teer efforts of the Nebraska National Guardsmen, are also gratefully
acknowledged for their assistance to the Survey.

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                                    IV

                      NATIONAL EUTROPHICATION SURVEY

                            STATE OF NEBRASKA

RESERVOIR NAME                                    COUNTY

Branched Oak                                      Lancaster
Harlan County                                     Harlan
Harry D. Strunk                                   Frontier
Hugh Butler                                       Frontier, Red  Willow
Johnson                                           Dawson,  Gosper
McConaughy                                        Keith
Pawnee                                            Lancaster
Sherman                                           Sherman
Swanson                                           Hitchcock

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                           41 10 —
BRANCHED OAK RESERVOIR

    <8> Tributary Sampling Site
    X Lake Sampling Site
      Drainage Area Boundary
      Land Subject to Inundation

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                          BRANCHED OAK RESERVOIR
                             STORE! NO. 3101

I.  CONCLUSIONS
    A.  Trophic Condition:
            Survey data indicate that Branched Oak Reservoir is eutro-
        phic.  It ranked second in overall  trophic quality when
        the nine Nebraska reservoirs sampled  in 1974 were compared using  a
        combination of six parameters*.  One  of the other reservoirs  had
        less median total phosphorus, three had less median dissolved phos-
        phorus, none of the others had less median inorganic nitrogen,
        six had less mean chlorophyll a_, and  three had greater mean Secchi
        disc transparency.  Survey limnologists noted a phytoplankton
        bloom in progress at station 1 in April.
            Branched Oak Reservoir receives runoff water high in dissolved
        nutrients principally from cultivated farmland, and the reservoir
        has had symptoms of eutrophy since the second year of impoundment
        (Hammer and Hergenrader, 1974).
    B.  Rate-Limiting Nutrient:
            Because of nutrient losses in the samples, the algal assay
        results are not considered indicative of conditions in the reser-
        voir at the times of sampling (04/17/74 and 09/26/74).   The reser-
        voir data indicate nitrogen limitation at both sampling times.
    C.  Nutrient Controllability:
            1.  Point sources—No  known point sources impacted Branched
* See Appendix A.

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                                   2
      Oak Reservoir during the sampling year.   Nonetheless,  the
      present phosphorus loading of 0.72 g/m2/yr is more than twice
      that proposed by Vollenweider (Vollenweider and Dillon, 1974)
      as a eutrophic loading (see page 11).   Any reduction of nutrient
      inputs to the reservoir will require control  of non-point source
      contributions (see below).
          2.  Non-point sources—The phosphorus loads of the two gaged
      tributaries amounted to 63.5% of the total load reaching the
      reservoir.  The estimated phosphorus load of the ungaged streams
      amounted to 34.1% of the total load.
          Because of the lack of point sources and the agricultural
      practices in the watershed (Sheets, 1975), reduction of nutrient
      inputs is dependent on improved land-use practices in the drainage
      area.
          The phosphorus export rates of Oak and Middle Oak creeks (see
      page 10) compare well with those of unimpacted Middle Creek and
      Unnamed Stream B-l, tributaries of nearby Pawnee Reservoir* (26
      kg/km2/yr).
Working Paper No. 560.

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II.   LAKE AND DRAINAGE  BASIN  CHARACTERISTICS1"
     A.   Lake Morphometry   :
         1.   Surface  area:  7.28  kilometers2.
         2.   Mean  depth:  5.5 meters.
         3.   Maximum  depth:   11.0 meters.
         4.   Volume:  40.040  x  106 m3.
         5.   Mean  hydraulic retention time:  2.8 years (based on outflow),
     B.   Tributary and  Outlet:
         (See Appendix  C for  flow data)
         1.   Tributaries -
                                              Drainage       Mean flow
             Name                              area (km2)*    (m3/sec)*
             Oak Creek                             73.8           0.26
             Middle Oak Creek                     60.6           0.22
             Minor tributaries  &
              immediate drainage  -                 73.0           0.28
                        Totals                   207.4           0.76
         2.   Outlet -
             Oak Creek                            214.7**         0.46
     C.   Precipitation***:
         1.   Year  of  sampling:  60.4 centimeters.
         2.   Mean  annual:  67.7 centimeters.
 t Table of metric conversions—Appendix B.
 tt Adamovich,  1975; Hartung, 1974.
 * For  limits of accuracy, see Working Paper No. 175, "...Survey Methods,
  1973-1976".
 ** Includes area of reservoir.
 ***  See Working Paper No. 175.

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                                       4
III.   LAKE WATER QUALITY SUMMARY
      Branched Oak Reservoir was sampled three  times during the open-
  water season of 1974 by means of a pontoon-equipped Huey helicopter.
  Each time,  samples for physical  and chemical  parameters were collected
  from three  stations on the reservoir and  from a  number of depths
  at  each station (see map,  page v).  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 enumeration; and during the first and third  visits, 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 10.7 meters at station 1, 7.6  meters at station 2,
  and 6.1 meters at station  3.
      The sampling results are  presented in full in Appendix D and
  are summarized in the following table (the  July  nutrient samples
  were not preserved properly and were not  analyzed).

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                             A. SUMMARY OF PHYSICAL AND CHEMICAL CHARACTERISTICS FOR BRANCHED OAK
                                                         STORET CODE 3101
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 (UG/L)

SECCHI  (METERS)
                             1ST SAMPLING ( 4/17/74)

                                   3 SITES
2ND SAMPLING (  7/ 2/74)

      3 SITES
RANGE
9.1
10.2
343.
218.
0 .025
0.004
0.020
0.020
0.600
0/\f. n
• UHU
0.660
10.4
1.4
9.7
- 10.6
- 348.
- 226.
~ 0.044
- 0.013
- 0.060
~ 0.050
•" 0.900
v n 1 1 n
0 . 1 10
- 0.950
- 12.9
1.4
MEAN
9.4
10.5
346.
222.
0*031
0.009
0.045
0.038
0.782
Oft B i
• OB J
0.826
11.4
1.4
MEDIAN
9.4
10.6
345.
222.
0.030
0.009
0.050
0.040
0. 800
0 .090
0.840
11.0
1.4
RANGE MEAN
22.7 - 23.5 23.2
5.6 - 6.2 5.9
468. - 475. 472.
MEDIAN
23.4
6.0
471.
7.8 - 8.0 7.8 f.o
oooooo -eo«e«oeooeaa«a»e*«o*»*
eoaeao .aooaeooooeaooooaoaoooo






«««**« -»«00»000»»tt»»»»OOOO»«t«
6.4 - 27.5 14.6
0.9 - 0.9 0.9
9.8
0.9
                                                                                                    0.9  -
                                                                                                             1.1
                                                0.081

                                                0.044

                                                0.910

                                                0.125

                                                0.991

                                                 25.1

                                                  1.0
                                                          8.5

                                                         406.

                                                          7.8

                                                         274.
       3RD SAMPLING ( 9/26/74)

             3 SITES

     RANGE

 17.1  -  18.1

  7.4  -   9.2

 403.  -  412.

  7.7  -   7.8

 242.  -  290.

0.059  - 0.096

0.023  - 0.030

0.020  - 0.620

0.040  - 0.050

0.700  - 1.200

0.060  - 0.670

0.720  - 1.520

 21.1  -  32.1
 MEAN   MEDIAN

 17.5    17.3

  8.5

 407.

  7.8

 271.

0.076   0.078

0.026   0.025

        0.020

        0.040

        0.900

        0.060

        0.970

         22.1
                                                                                                                              1.1

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B.  Biological characteristics:

    1.   Phytoplankton -

        Sampling
        Date

        04/17/74
        07/02/74
        09/26/74
    2.   Chlorophyll  a_ -

        Sampling
        Date

        04/17/74
        07/02/74
        09/26/74
   Dominant
   Genera

   1.  Asterionella sp.
   2.  Flagellates
   3.  Dinobryon sp.
   4.  Cryptomonas sp.
   5.  Ankistrodesmus sp.
       Other genera

                Total

       Car ten'a sp.
       Flagellates
       Cryptomonas sp.
       Cysts
       Aphanizomenon sp.
       Other genera

                Total

   1.  Melosira sp.
   2.  Cryptomonas sp.
   3.  Aphanizomenon sp.
   4.  Flagellates
   5.  Coelosphaerium sp.
       Other genera

                Total
                        Algal  Units
                        per ml	

                         15,728
                                                           2
                                                           1,
                            192
                            334
                            572
                            191
                            381
                                                          20,398
1.
2.
3.
4.
5.
1
,541
572
396
308
220
926
Station
Number

  1
  2
  3

  1
  2
  3

  1
  2
  3
                          3,963

                          5,603
                            580
                            515
                            322
                            258
                            773

                          8,051
                        Chlorophyll  a
                        (ug/D

                            10.4
                            11.0
                            12.9

                            27.5
                             9.8
                             6.4

                            22.1
                            32.1
                            21.1

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                                 7
C.   Limiting Nutrient Study:
        There was a significant change in nutrients  in  the algal
    assay samples from the time of  collection  to  the beginning of
    the assays.   Therefore, the results are not considered repre-
    sentative of conditions in the  reservoir at the  times of  sam-
    pling.
        The reservoir data indicate nitrogen limitation; i.e., the
    mean inorganic nitrogen to orthophosphorus ratios were less
    than 10 to 1 both sampling times,  and nitrogen limitation would
    be expected.

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IV.   NUTRIENT LOADINGS
     (See Appendix E for data)
     For the determination of nutrient  loadings, the Nebraska National
 Guard collected monthly near-surface grab  samples from each of the
 tributary sites indicated on the map (page v), except for the high
 runoff months of May and June when  two samples were collected.
 Sampling was begun in August,  1974, and was completed in July, 1975.
     Through an interagency agreement,  stream flow estimates for the
 year of sampling and a "normalized" or average year were provided by
 the Nebraska District Office of the U.S. Geological Survey for the
 tributary sites nearest the reservoir.
     In this report, nutrient loads  for sampled tributaries were
 determined by using a modification  of  a U.S. Geological Survey computer
 program for calculating stream loadings*.  Nutrient loads shown are
 those measured minus point-source loads, if any.
     Nutrient loads for unsampled "minor tributaries and immediate
 drainage" ("ZZ" of U.S.G.S.) were estimated using the means of the
 nutrient loads, in kg/km2/year, at  stations A-2 and B-l and multiplying
 the means by the ZZ area in km2.
     No known point sources impacted Branched Oak Reservoir during the
 Survey sampling year.
   See Working Paper No.  175.

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                                     9
    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) -
                Oak Creek                     1,955           37.2
                Middle Oak Creek              1,380           26.3
            b.  Minor tributaries & immediate
                 drainage (non-point load) -  1,790           34.1
            c.  Known municipal STP's - None
            d.  Septic tanks - None
            e.  Known industrial - None
            f.  Direct precipitation* -         125            2.4
                        Total                 5,250          100.0
        2.  Outputs -
            Lake outlet - Oak Creek           1,035
        3.  Net annual P accumulation - 4,215 kg.
* See Working Paper No.  175.

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                                     10
    C.  Annual Total Nitrogen Loading - Average Year:
        1.  Inputs -
                                              kg N/
            Source                            yj;	
            a.  Tributaries (non-point load) -
                Oak Creek                     15,670
                Middle Oak Creek              15,290
            b.  Minor tributaries & immediate
                 drainage (non-point load) -  16,935
            c.  Known municipal STP's - None
            d.  Septic tanks - None
            e.  Known industrial - None
            f.  Direct precipitation* -        7,860
                        Total                 55,755
        2.  Outputs -
            Lake outlet - Oak Creek           16,065
        3.  Net annual N accumulation - 39,690 kg.
    D.  Non-point Nutrient Export by Subdrainage Area:
        Tributary                             kg P/km2/yr
        Oak Creek
        Middle Oak Creek
    26
    23
    E.  Mean Nutrient Concentrations in Ungaged Streams:
        Tributary
        Oak Creek (station A-3)
        Unnamed Stream C-l
Mean Total P
Cone, (mg/1)
    0.206
    0.248
               % of
               total
                28.1
                27.4
                30.4
                14.1
               100.0
kg N/km2/yr
    212
    252
Mean Total  N
Cone, (mg/1)
    2.069
    2.779
* See Working Paper No. 175.

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                                11
F.   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.
                              Tot a 1[ P hosjjhorus       Total Nitrogen
    	TotaH   Accumulated    Total   Accumulated
    grams/m2/yr             0.72      0.58        7.7         5.5
    Vollenweider phosphorus  loadings
     (g/m2/yr)  based on mean depth and mean
     hydraulic  retention time of Branched Oak Reservoir:
        "Dangerous"   (eutrophic loading)             0.28
        "Permissible"  (oligotrophic  loading)       0.14

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                                    12

V.  LITERATURE REVIEWED

    Adamovich, Ted, 1975.  Personal conmunication (reservoir mor-
        phometry).  NE Dept. of Environ.  Contr.,  Lincoln.

    Hammer, Mark J., and Gary L. Hergenrader, 1974.   Eutrophication
        of small reservoirs in eastern Nebraska.   Trans.  NE  Acad.
        Sci., vol II.

    Hartung, Ray, 1974.  Personal communication (reservoir morphometry).
        NE Dept. of Environ. Contr., Lincoln.

    Hergenrader, Gary L., and Mark J. Hammer, 1973.   Eutrophication  of
        small reservoirs in the Great Plains.  In:  Man-made lakes:
        Their problems and environmental  effects  (W.  C.  Ackerman,  G.  F.
        White, & E. B. Worthington, eds\).   Geophys.  Monogr. Ser.,
        vol. 17.

    Sheets, Wes, 1975.  Personal communication (general  watershed  infor-
        mation).  NE Game & Parks Comm.,  Lincoln.

    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.

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VI.  APPENDICES
                                     APPENDIX A
                                    LAKE  RANKINGS

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LAKE DATA TO BE USED IN RANKINGS
LAKE
CODE  LAKE NAME
3101  BRANCHED OAK
3102  HARLAN COUNTY RESERVOIR
3103  HARRY D. STRUNK (MEDICIN
3104  HUGH BUTLER (RED WILLOW)
3105  JOHNSON RESERVOIR
3106  LAKE MCCONAUGHY
3107  PAWNEE LAKE
3108  SHERMAN COUNTY RESERVOIR
3110  SWANSON RESERVOIR
MEDIAN
TOTAL P
0.044
0.112
0.064
0.061
0.075
0.027
0.060
0.067
0.067
MEDIAN
INORG N
0.070
0.365
0.460
0.090
0.340
0.585
0.175
0.090
0.090
500-
MEAN SEC
456.444
476.111
470.500
468. d75
477.667
409.555
453.000
451.167
466. J33
MEAN
CHLORA
17.033
27.822
14.367
16.61?
26.133
8.644
15.367
6.717
14.450
15-
MIN DO
9.400
12.200
14.200
14.400
8.600
11.400
8.800
11.800
11.000
MEDIAN
DISS OrtlHO f
0.013
0.061
0.009
O.OU
O.OOsi
0.004
0.020
0.050
0.016

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PERCENT OF LAKES .KITH HIGHER VALUES  (NUMBER OF LAKES XlTH HIGHEK VALUES)
LAKE
CODE  LAKE NAME
3101  BRANCHED OAK
3103  HARLAN COUNTY RESERVOIK
3103  HARRY 0. STRUNK (MEDICIN
3104  HUGH BUTLER (RED WILLO*)
3105  JOHNSON RESERVOIR
3106  LAKE MCCONAUGHY
3107  PAWNEE LAKE
3108  SHERMAN COUNTY RESERVOIR
3110  SWANSON RESERVOIR
MEDIAN
TOTAL P
SB (
0 (
50 (
63 (
13 (
100 (
75 (
38 (
as (
7)
0)
4)
5)
1)
8)
6)
3)
2>
MEDIAN
INOKG
100 (
as <
13 (
75 (
38 (
0 (
50 (
75 (
75 (
N
8)
2)
1)
5)
3)
0)
4)
5)
5)
500-
MEAN SEC
63 (
13 (
as <
38 (
0 (
100 (
75 (
88 (
50 (
5)
1)
2)
3)
0)
8)
b)
7)
4)
MEAN
CHLORA
25 (
0 <
75 (
38 I
13 (
88 (
50 (
100 (
63 (
2)
0)
6)
3)
1)
7)
4)
8)
S)
15-
MIN DO
75 (
25 (
13 (
0 (
100 (
50 (
88 (
38 f
63 (
6)
2)
1)
0)
8>
4)
7)
3)
5)
MEuIAN
DISS OkTHO P
63 (
0 (
81 (
50 (
81 (
100 (
25 (
13 (
38 (
5)
0)
6)
4)
6)
8)
2)
1)
3)
1NJEX
NO
<*14
63
257
264
245
4J8
363
3*2
314

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LAKES RANKED BY INDEX NOS.
RANK  LAKE CODE  LAKE NAME               INDEX NO
   1  3106       LAKE MCCONAUGHY            438
   2  3101       BRANCHED OAK               414
   3  3107       PAWNEE LAKE                363
   4  3108       SHERMAN COUNTY RESERVOIR   352
   5  3110       SWANSON RESERVOIR          314
   6  3104       HUGH SUTLER (RED WILLOW)   264
   7  3103       HARRY D. STRUNK (MEDICIN   257
   8  3105       JOHNSON RESERVOIR          245
   
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    APPENDIX B
CONVERSION FACTORS

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                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

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    APPENDIX C
TRIBUTARY FLOW DATA

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                                   TRIBUTARY FLOW INFORMATION FOR NEBRASKA

LAKE CODE 3101     BRANCHED OAK LAKE

     TOTAL DRAINAGE AREA OF LAKE(SO KM)    214.7
                                                                             12/23/75
          SUB-DRAINAGE
TRIBUTARY  AREAfSQ KM)
                          JAN
                                  FEB
                                          MAR
                                                  APR
                                                          MAY
                                                   NORMALIZED FLOWS(CMS)
                                                     JUN     JUL     AUG
                                                                                          SEP
                                                                                                  OCT
                                                                                                          NOV
                                                                                                                  DEC
                                                                                                                         MEAN
3101A1
3101A2
3101B1
310 HZ
214.7
 73.8
 60.6
 80.3
0.37 0.62 0.76 0.82
0.24 0.31 0.45 0.40
0.1* 0.25 0.37 0.34
0.25 0.34 0.48 0.42
0.71
0.48
0.40
0.54
0.51
0.26
0.22
0.28
0
0
0
0
.22
.13
.10
.13
0.08
0.07
0.06
0.08
0.08
0.13
0.10
0.14
0
0
0
0
.74
.34
.27
.34
0.34
0.20
0.16
0.21
0.31
0.16
0.13
0.17
0.46
0.26
0.22
0.28
SUMMARY
OTAL DRAINAGE AREA OF LAKE =
>UM OF SUB-DRAINAGE AREAS =
214.7
214.7






TOTAL FLOW
TOTAL FLOW
IN =
OUT «


9.15
5.56






     MEAN MONTHLY FLOWS AND DAILY FLOWS(CMS)
TRIBUTARY   MONTH   YEAR
3101A1
                            MEAN FLOW  DAY
3101A2
8
9
10
11
12
1
2
3
4
5
6
7
8
8
9
10
11
12
1
2
3
4
5
6
7
74
74
74
74
74
75
75
75
75
75
75
75
75
74
74
74
74
74
75
75
75
75
75
75
75
0.03
0.0
0.0
0.0
0.0
O.U
0.06
0.68
1.22
0.82
0.74
0.25
0.08
0.15
0.05
0.13
0.06
0.08
0.11
0.14
0.37
0.48
0.27
0.42
0.06
24
21
19
15
7
12
2
11
12
4
7
12

25
22
20
16
14
19
22
16
13
2
8

                                      FLOW  DAY

                                      0.0
                                      0.0
                                      0.0
                                      0.0
                                      0.0
                                      0.0
                                      0.0
                                      0.42
                                      1.22
                                      1.22
                                      0.34
                                      0.14

                                      0.05
                                      0.05
                                      0.03
                                      0.06
                                      0.05
                                      0.0
                                      0.0
                                      0.11
                                      0.13
                                      0.06   17
                                      0.07   22
                                                                     FLOW  DAY
                                                                                       FLOW
                                                                     0.05
                                                                     0.06

-------
LAKE CODE 3101
                TRIBUTARY FLOW INFORMATION FOR NEBRASKA

BRANCHED OAK LAKE
                                                                                          12/23/75
     MEAN MONTHLY FLOWS AND DAILY FLOWS(CMS)

TRIBUTARY   MONTH   fEAR    MEAN FLOW  DAY

310161
3101ZZ
8
9
10
11
12
1
2
3
4
5
6
7
8
9
10
11
12
1
2
3
4
5
6
7
74
74
74
74
74
75
75
75
75
75
75
75
74
74
74
74
74
75
75
75
75
75
75
75
0.12
0.04
0.10
0.05
0.07
0.09
0.11
0.31
0.40
0.22
0.34
0.05
0.16
0.05
0.14
0.06
0.08
0.12
0.15
0.40
0.54
0.28
0.45
0.06
25
22
20
16
14
19
22
16
13
2
8

25
22
20
16
14
19
22
16
13
2
8

                                FLOW  DAY
FLOW  DAY
FLOW
0.04
0.08
0.05
0.06
0.05
0.0
0.0
0.07
0.08
0.07
0.05
0.06
0.08
0.05
0.07
0.06
0.0
0.0
0.11
0.12
0.08
0.07









17
22









17
22
                                                                     0.05
                                                                     0.07
                                                                     0.06
                                                                     0.08

-------
        APPENDIX D
PHYSICAL and CHEMICAL DATA

-------
STORE! RETRIEVAL DATE 75/12/33
                                                                  310101
                                                                 40 58 14.0 096 51 16.0
                                                                 BRANCHED OAK
                                                                 31109   NEBRASKA

DATE
FROM
TO
74/04/17



74/07/02



74/09/26





TIME DEPTH
OF

DAY FEET
10 35
10 35
10 35
10 35
10 25
10 25
10 25
10 25
13 45
13 45
13 45
13 45
0000
0005
0015
0035
0000
0005
0015
0028
0000
0005
0015
0027
00010
WATER
TEMP
CENT
9.7
9.7
9.7
9.5
23.5
23.4
23.4
23.3
18.1
18.1
17.8
17.2
HEP ALES

00300
DO

MG/L

10.6
10.6
10.6
5.6
6.0
6.0
5.6
9.0
8.2
9.0
7.4

00077
TRANSP
SECCHI
INCHES
54



36



36




00094
CNDUCTVY
FIELD
MICROMHO
348
348
348
347
474
474
474
475
412
412
410
406
3
00400
PH

SU




7.90
8.00
7.90
7.80
7.85
7.84
7.80
7.66

00410
T ALK
CAC03
MG/L
220
220
222
218




278
284
276
266
2111202
0040
00610
NH3-N
TOTAL
MG/L
0.040
0.050
0.030
0.040




0.040
0.050
0.050
0.050
FEET DEPTH
00625
TOT KJEL
N
MG/L
0.600
0.700
0.800
0.800




1.100
1.000
0.900
0.800
00630
N02&N03
N-TOTAL
MG/L
0.060
0.060
0.020
0.060




0.020
0.020
0.620
0.020
00671
PHOS-DIS
ORTHO
MG/L P
0.004
0.009
0.013
0.009




0.028
0.030
0.025
0.023
                      00665
  DATE   TIME DEPTH PHOS-TOT
  FROM    OF
   TO    DAY  FEET   MG/L P
74/04/17



74/07/02

74/09/26




10
10
10
10
10
10
13
13
13
13
13
35
35
35
35
25
25
45
45
45
45
45
0000
0005
0015
0035
0000
0008
0000
0005
0007
0015
0027
0.
0,
0,
0.


0,
0,

0.
0,
,025
,044
,034
,030


.087
,096

.077
,059
  32217     00031
CHLRPHYL  INCDT LT
   A      REMNING
  UG/L    PERCENT

    10.4
                                  27.5

                                  22.1
               1.0


               1.0

-------
STORET RETRIEVAL DATE 75/12/23
                                                                  310102
                                                                 40 SB 45.0 096 52 12.0
                                                                 BRANCHED OAK
                                                                 31109   NEBRASKA



DATE
FROM
TO
74/04/17



74/07/02



74/09/26



DATE
FROM
TO
74/04/17



74/07/02

74/09/26






TIME DEPTH
OF
DAY FEET
11 05 0000
11 05 0005
11 05 0015
11 05 0020
11 00 0000
11 00 0005
11 00 0015
11 00 0025
13 30 0000
13 30 0005
13 30 0015

TIME DEPTH
OF
DAY FEET
11 05 0000
11 05 0005
11 05 0015
11 05 0020
11 00 0000
11 00 0005
13 30 0000
13 30 0004
13 30 0005
13 30 0015


00010
WATER
TEMP
CENT
9.4
9.4
9.4
9.4
23.5
23.5
23.5
23.4
17.6
17.5
17.2
00665
PHOS-TOT

MG/L P
0.028
0.030
0.030
0.028


0.083

0.082
0.066


00300
DO

MG/L

10.6
10.6
10.6
6.0
6.0
6.0
6.0
8.6
9.2
8.6
32217
CHLRPHYL
A
UG/L
11.0



9.8

32.1





00077
TRANSP
SECCHI
INCHES
56



36



42


00031
INCDT LT
REMNING
PERCENT





1.0

1.0




00094
CNDUCTVY
FIELD
MICROMHO
343
345
345
346
472
470
470
475
406
405
403














11EPALES
3
00400 00410
PH T ALK
CAC03
SU Mli/L
222
220
222
226
7.90
7.90
7.80
7.80
7.79 278
7.78 260
7.76 260














2111202
0030
00610
NH3-N
TOTAL
MG/L
0.030
0.050
0.020
0.050




0.050
0.040
0.040














FEET DEPTH
00625
TOT KJEL
N
MG/L
0.700
0.800
0.900
0.800




1.200
1.000
0.900














00630
N02&N03
N-TOTAL
MG/L
0.030
0.060
0.020
0.060




0.030
0.020
0.020














00671
PHOS-DIS
ORTHO
MG/L P
0.009
0.008
0.011
0.012




0.030
0.027
0.025















-------
STORE! RETRIEVAL DATE 75/12/23
                                                                  310103
                                                                 40 57 25.0 096 52 19.0
                                                                 BRANCHED OAK
                                                                 31109   NEBRASKA

DATE
FROM
TO
74/04/17


74/07/02



74/09/26



TIME DEPTH
OF
DAY FEET
11 30 0000
11 30 0005
11 30 0012
11 20 0000
11 20 0005
11 20 0015
11 20 0020
14 15 0000
14 15 0005
14 15 0010
00010
WATER
TEMP
CENT
9.2
9.2
9.1
22.9
22.8
22.8
22.7
17.2
17.1
17.1
11EPALES

00300
00

MG/L

10.2
10.4
6.0
5.8
5.8
6.2
8.4
8.4
8.0

00077
TRANSP
SECCHI
INCHES
54


36



42



00094
CNDUCTVY
FIELD
MICROMHO
344
344
343
469
469
468
469
406
404
404
3
00400
PH

SU



7.80
7.80
7.80
7.80
7.73
7.73
7.74

00410
T ALK
CAC03
MG/L
226
226
224




290
242
272
2111202
0017
00610
NH3-N
TOTAL
MG/L
0.040
0.040
0.030




0.040
0.040
0.040
FEET DEPTH
00625
TOT KJEL
N
MG/L
0.900
0.800
0.800




0.800
0.700
0.700
00630
N02&N03
N-TOTAL
MG/L
0.050
0.040
0.030




0.020
0.020
0.020
00671
PHOS-OIS
ORTHO
MG/L P
0.005
0.005
0.009




Oc023
0.023
Oo023
                      00665     32217     00031
  DATE   TIME DEPTH PHOS-TOT  CHLRPHYL  INCDT LT
  FROM    OF                     A      REMNING
   TO    DAY  FEET   MG/L P     UG/L    PERCENT

74/04/17 11 30 0000    0.038      12.9
         11 30 0005    0.031
         11 30 0012    0.028
74/07/02 11 20 0000                6.4
         11 20 0006                          1.0
74/09/26 14 15 0000    0.068      21.1
         14 15 0005    0.079
         14 15 0007                          1.0
         14 15 0010    0.067

-------
  APPENDIX E
TRIBUTARY DATA

-------
STORET RETRIEVAL DATE 76/01/27
                                                                  3101A1
                                                                 40 57 59.0 096 50 30.0
                                                                 OAK CREEK
                                                                 31029   7.5 RAYMOND
                                                                 0/BRANCHED OAK LAKE
                                                                 SEC RO 8RDG .7 MI SE OF BR OAK LAKE DAM
                                                                 HEPALES             2111204
                                                                 4                   0000 FEET  DEPTH
DATE
FROM
TO
74/08/24
74/09/21
74/10/19
74/11/15
74/12/07
75/01/12
75/02/02
75/03/11
75/04/12
75/05/04
75/06/07
75/07/12
00630 00625
TIME DEPTH N02&N03 TOT KJEL
OF N-TOTAL N
DAY FEET
09
10
10
17
13
09
10
12
13
09
13
14
15
45
45
00
20
30
30
20
20
30
35
40
MG/L
0,
0,
0.
0,
0.
1,
1,
0,
0.
.820
.830
,736
.880
,830
.400
.720
.062
.070
0.030
0,
0.
,075
,105
MG/L
0.400
0.300
0.400
0.300
0.500
1.900
1.100
1.200
0.950
0.950
1.000
1.100
00610 00671 00665
NH3-N PHOS-DIS PHOS-TOT
TOTAL ORTHO
MG/L
0.050
0.040
0.050
0.065
0.085
0.144
0.212
0.058
0.075
0.035
0.105
0.100
MG/L P
0
0
0
0
0
0
0
0
0
.310
.280
.360
.330
.300
.320
.180
.031
.015
0.020
0
0
.055
.070
MG/L P
0.340
0.300
0.420
0.350
0.440
0.600
0.240
0.070
0.070
0.040
0.090
0.100

-------
STORET RETRIEVAL DATE 76/01/27
                                                                  3101A2
                                                                 41 00 33.0 096 54 40.0
                                                                 OAK CREEK
                                                                 31      7.5 VLPRAISO SW
                                                                 T/BRANCHEO OAK LAKE
                                                                 CO RD BRDG 8 MI ME OF GARLAND
                                                                 11EPALES             2111204
                                                                 4                   0000 FEET  DEPTH

DATE
FROM
TO
74/08/25
74/09/22
74/10/20
74/11/16
74/12/14
75/03/16
75/04/13
75/05/02
75/05/17
75/06/08
75/06/22

TIME DEPTH
OF
DAY FEET
10 00
10 20
10 00
15 15
10 05
15 00
14 30
14 40
09 47
14 30
14 00
00630
N02&N03
N-TOTAL
MG/L
1.010
1.080
0.240
1.060
0.990
0.935
0.490
0*310
0.670
0.440
0.610
00625
TOT KJEL
N
MG/L
0.500
1.100
0.500
0.500
0.400
2.000
0.900
1.350
0.350
1.250
2.400
00610
NH3-N
TOTAL
MG/L
0.075
0.165
0.035
0.085
0.045
0.169
0.220
0.095
0.200
0.165
0.120
00671
PHOS-DIS
ORTHO
MG/L P
0.200
0.175
0.055
0.040
0.090
0.175
0.125
0.130
0.190
0.210
0.345
00665
PHOS-TOT

MG/L P
0.230
0.195
0.140
0.110
0.140
0.230
0.180
0.190
0.348
0.350
0.750

-------
STORE! RETRIEVAL DATE 76/01/27
                                                                  3101A3
                                                                 41  05  23.0  096  57  24.0
                                                                 OAK CREEK
                                                                 31       7.5 VLPRAISO  S*
                                                                 T/BRANCHEO  OAK  LAKE
                                                                 SEC RD BROG 3.5 MI ENE OF  DMIGHT
                                                                 11EPALES             2111204
                                                                 4                  0000 FEET   DEPTH

DATE
FROM
TO
74/08/25
74/09/22
74/10/20
74/11/16
74/12/14
75/03/16
75/04/13
75/05/02
75/05/17
75/06/08
75/06/22

TIME DEPTH
OF
DAY FEET
09 20
09 45
09 30
14 35
09 35
14 30
14 05
14 10
09 30
14 05
13 37
00630
N02&N03
N-TOTAL
MG/L
0.840
1.920
0.736
1.060
1.240
0.764
0.540
0.370
1.100
0.750
0.510
00625
TOT KJEL
N
MG/L
0.300
0.900
0.400
1.700
1.000
2.700
1.150
1.150
0.650
1.250
1.730
00610
NH3-N
TOTAL
MG/L
0.015
0.120
0.027
0.055
0.065
0.089
0.165
0.315
0.185
0.065
0.220
00671
PHOS-DIS
ORTHO
MG/L P
0.160
0.230
0.180
0.080
0.115
0.184
0.105
0.115
0.080
0.145
0.220
00665
PHOS-TOT

MG/L P
0.164
0.240
0.210
0.160
0.150
0.210
0.140
0.160

0.260
0.370

-------
STORE! RETRIEVAL DATE 76/01/27
                                                                  310181
                                                                 40 58 48.0 096 55 45.0
                                                                 MIDDLE OAK CREEK
                                                                 31      7.5 GARLAND
                                                                 T/BRANCHED OAK LAKE
                                                                 CO RD BROG 5.2 MI NE OF GARLAND
                                                                 11EPALES             2111204
                                                                 4                   0000 FEET  DEPTH

DATE
FROM
TO
74/08/25
74/09/22
74/10/20
74/11/16
74/12/14
75/03/16
75/04/13
75/05/02
75/05/17
75/06/08
75/06/22

TIME DEPTH
OF
DAY FEET
10 15
10 40
10 10
15 30
10 15
15 15
14 45
14 50
10 00
14 40
14 14
00630
N02&N03
N-TOTAL
MG/L
1.720
1.920
0.672
1.440
1.360
0.957
0.525
0.480
0.810
0.430
0.760
00625
TOT KJEL
N
MG/L
0.600
0.900
0.600
0.700
0.700
1.900
1.050
1.500
0.650
0.930
2.200
00610
NH3-N
TOTAL
MG/L
0.045
0.045
0.030
0.075
0.125
0.273
0.330
0.395
0.105
0.085
0.150
00671
PHOS-DIS
ORTHO
MG/L P
0.115
0.155
0.125
0.105
0.095
0.184
0.085
0.123
0.160
0.160
0.270
00665
PHOS-TOT

MG/L P
0.160
0.230
0°140
OoUO
0.140
0*300
0.190
0.180
0.222
0.210
0.500

-------
STORE! RETRIEVAL DATE 76/01/27
                                                                  3101C1
                                                                 41  01  00.0 096 54 32.0
                                                                 UNNAMED  CREEK
                                                                 31       7.5 VLPRAISO SW
                                                                 T/3RANCHEO OAK
                                                                 AT  SEC RO BRDG 4.0 MI W OF AGNEM
                                                                 11EPALES             2111204
                                                                 4                   0000 FEET  DEPTH

DATE
FROM
TO
74/08/25
74/09/22
74/10/20
74/11/16
74/12/14
75/02/22
75/03/16
75/04/13
75/05/02
75/05/17
75/06/08
75/06/22

TIME DEPTH
OF
DAY FEET
09 50
10 10
09 55
15 00
10 00
14 15
14 45
14 25
14 30
09 40
14 20
13 54
00630
N02&N03
N-TOTAL
MG/L
0.570
0.416
0.248
0.504
3.000
3.050
3.135
0.710
0.760
0.500
0.300
0.380
00625
TOT KJEL
N
MG/L
1.300
1.500
1.200
1.500
1.000
2.400
2.950
2.600
1.800
0.275
1.500
1.750
00610
NH3-N
TOTAL
MG/L
0.120
0.115
0.055
0.345
0.200
0.464
0.524
0.075
0.490
0.165
0.145
0.220
00671
PHOS-DIS
ORTHO
MG/L P
0.150
0.100
0.125
0.140
0.025
0.040
0.267
0.040
0.110
0.105
0.115
0.130
00665
PHOS-TOT

MG/L P
0.290
0.260
0.320
0.230
0.160
0.260
0.385
0.220
0.190
0.205
0.200
0.260

-------
STORET RETRIEVAL DATE 76/01/27
                                                                  31011C
                                                                 40 54 03.0 096 48 21.0
                                                                 WEST OAK CREEK
                                                                 31109   7.5 RAYMOND
                                                                 T/BRANCHEO OAK LAKE
                                                                 SEC WO 8ROG 3.1 MI E OF MALCOLM
                                                                 11EPALES             2111204
                                                                 4                   0000 FEET  DEPTH

DATE TIME DEPTH
FROM OF
TO DAY FEET
74/08/24 09 45
74/09/21 11 15
74/10/19 10 15
74/11/15 16 30
74/12/07 13 45
75/01/12 10 25
75/02/02 09 45
75/03/16 12 00
75/04/12 14 00
75/05/04 10 40
75/06/07 13 10
75/07/12 13 35
00630
N02&N03
N-TOTAL
MG/L
3.200
2.900
2.080
1.840
1.550
4.000
0.850
1.445
0.735
0.840
1.250
2.200
00625
TOT KJEL
N
MG/L
1.000
0.600
0.700
0.600
0.600
1.100
0.500
1.600
1.000
1.700
0.700
1.050
00610
NH3-N
TOTAL
MG/L
0.050
0.035
0.045
0.080
0.040
0.096
0.124
0.196
0.065
0.060
0.020
0.165
00671
PHOS-DIS
ORTHO
MG/L P
0.400
0.315
0.290
0.260
0.230
0.368
0.264
0.231
0.180
0.190
0.310
0.350
00665
PHOS-TOT

MG/L P
0.480
0.375
0.360
0.340
0.320
0.600
0.440
0.370
0.290
0.270
0.340
0.440

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