U.S. ENVIRONMENTAL PROTECTION AGENCY
           NATIONAL EUTROPHICATION SURVEY
                    WORKING PAPER SERIES
                                          REPORT
                                            ON
                                         TOPAZ LAKE
                                    DOUGLAS COUNTY, NEVADA
                                    mm COUNTY, CALIFORNIA
                                        EPA REGION IX
                                     WORKING PAPER No, 811
 CORVALLIS ENVIRONMENTAL RESEARCH LABORATORY - CORVALLIS, OREGON
                             and
ENVIRONMENTAL MONITORING & SUPPORT LABORATORY - LAS VEGAS, NEVADA

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                                   REPORT
                                     ON
                                 TOPAZ LAKE
                           DOUGLAS COUNTY, NEVADA
                           MONO COUNTY, CALIFORNIA
                                EPA REGION IX
                            WORKING PAPER No, 811
      WITH THE COOPERATION OF THE
NEVADA ENVIRONMENTAL PROTECTION SERVICE
               AND THE
         NEVADA NATIONAL GUARD
            SEPTEMBER. 1977

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            REPORT ON TOPAZ LAKE

           DOUGLAS COUNTY, NEVADA

           MONO COUNTY, CALIFORNIA

                EPA REGION IX


                     by

       National Eutrophtcation Survey

        Water and Land Quality Branch
       Monitoring Operations Division
Environmental Monitoring & Support Laboratory
              Las Vegas, Nevada

                     and

           Special Studies Branch
 Corvallis Environmental Research Laboratory
              Corvallis, Oregon
            Working Paper No. 811
     OFFICE OF RESEARCH AND DEVELOPMENT
    U.S. ENVIRONMENTAL PROTECTION AGENCY

               September  1977

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                               CONTENTS

                                                         Page
Foreword                                                  ii
List of Nevada Study Lakes                                iv
Lake and Drainage Area Map                                 v
Sections
  I.  Conclusions                                          1
 II.  Lake and Drainage Basin Characteristics              4
III.  Lake Water Quality Summary                           6
 IV.  Nutrient Loadings                                   12
  V.  Literature Reviewed                                 17
 VI.  Appendices                                          18

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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, concen-
 trations, 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 nonpoint source pollution abatement in lake water-
 sheds.

 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
watershed 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)],  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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                                  Hi

     Beyond the single lake analysis, broader based correlations
between nutrient concentrations (and loading) and trophic
condition 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 the U.S. Environmental Protection Agency and to augment
plans implementation by the States.

ACKNOWLEDGMENTS

     The staff of the National Eutrophication Survey (Office
of Research and Development, U.S. Environmental Protection
Agency) expresses sincere appreciation to the Nevada State
Environmental Protection Service, the California State Water
Resources Control Board and the California Regional Water Quality
Control Board for professional involvement, to the Nevada and
California National Guards for conducting the tributary sampling
phase of the Survey, and to those Nevada and California
wastewater treatment plant operators who provided effluent
samples and flow data.

     The staff of the Department of Conservation and Natural
Resources, Division of Environmental Protection, Nevada
Environmental Protection Service, and the staffs of the Division of
Planning and Research of the California Water Resources Control
Board and the Regional Water Quality Control Board, 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 Floyd L. Edsall, the Adjutant General of
Nevada, and Project Officer Major Harold E. Roberts, who directed
the volunteer efforts of the Nevada National Guardsmen, and
Major General Glen C. Ames, the Adjutant General of California,  and
Project Officer Second Lieutenant Terry L. Barrie, who directed
the volunteer efforts of the California National Guardsmen are
also gratefully acknowledged for their assistance to the Survey.

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                                 IV
                    NATIONAL EUTROPHICATION SURVEY
                              STUDY LAKES
                            STATE OF NEVADA
LAKE NAME
Lake Mead
Lahpntan Reservoir
Rye Patch Reservoir
Lake Tahoe

Topaz Reservoir
Upper Pahranagat Lake
Washoe Lake
Wildhorse Reservoir
Wilson Reservoir
Walker Lake
    COUNTY
Clark (Mohave in Arizona)
Lyon, Churchill
Pershing
Washoe, Carson City,
Douglas (Placer,
El Dorado in CA)
Douglas (Mono in CA)
Lincoln
Washoe
Elko
Elko
Mineral

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TOPAZ LAKE
                                    \
    TOPAZ LAKE
 ® Tributary  Sampling Site
 X Lake Sampling Site
o        5       10       is Km.
                                       21/2     5
                                            Scale
                    71/2 Mi.
                                                      \      38° 30'-
                                                       \
                                                                 \
                                             Map Location
                                                              38°15'-

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                    REPORT ON TOPAZ LAKE, NEVADA
                            STORET  NO,  3206

I.    CONCLUSIONS
     A.    Trophic Condition:*
               Survey  data indicate that Topaz  Lake  is  eutrophic,  i.e.,
          nutrient rich and highly  productive.   Whether such  nutrient
          enrichment is to be considered beneficial  or  deleterious is
          determined by its actual  or potential impact  upon designated
          beneficial water uses  of  the lake.
               Chlorophyll a_ values in the lake ranged  from 3.2 yg/1
          in March to  11.1 yg/1  in  November  with a mean of 7.5 yg/1.
          The potential for primary productivity as  measured  by algal
          assay control yields was  high.  Marked depression of dis-
          solved oxygen occurred throughout  the lake in the hypolimnion
          in November.  Of the 10 Nevada lakes  sampled  in 1975, 6  had
          higher median total phosphorus levels (0.057  mg/1), 3 had
          higher median inorganic nitrogen values (0.165 mg/1), and
          4 had higher median orthophosphorus levels (0.041 mg/1)  than
          Topaz Lake.
               Survey limnologists  did not report any problem algal
          blooms or macrophytes  on  their visits to the  lake.

     *See Appendix E.

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B.   Rate-Limiting Nutrient:
          Algal assay results indicate Topaz Lake was limited by avail-
     able nitrogen.  The mean inorganic nitrogen to orthophosphorus
     (N/P) ratios in the lake data of 7/1  or less on each sampling
     occasion also suggest primary limitation by nitrogen.
C.   Nutrient Controllability:
     1.   Point sources -
               There were no known point sources impacting Topaz Lake
          during the sampling year.
                                                           2
               The present phosphorus loading of 1.36 g P/m /yr is
          greater than that proposed by Vollenweider as "eutrophic".
          The Carson River Basin Council of Governments (1974) reports
          that agricultural return flow from irrigated areas is a
          major cause of water quality deterioration in the Walker
          River Basin.  A closer examination of agricultural practices
          in the Topaz Lake drainage area  may provide answers to
          nutrient reductions.
     2.   Nonpoint sources -
               Unnamed Canal  (B-l)  contributed  97% of the total  phos-
          phorus load to the lake during the sampling year.  Water for
          the canal is diverted from the Walker River; however, actual
          contributions from the canal may be somewhat less than in-
          dicated since it is not known how much water is removed from
          Unnamed  Canal  via the West  Walker River.

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     It should be noted that estimations of annual  nutrient
loadings contributed by septic tanks around Topaz Lake may
be substantially underestimated.   Those U.S. Geological
Survey (USGS) quadrangles used for determining the  number
of shoreline residences located within 100 meters of the
lake were dated in the 1950's.  Thus the present number of
septic tanks in the area in not known; neither has  it been
ascertained if those outside the 100 meter unit (U.S. EPA,
1975) do contribute nutrients to the lake as has been sug-
gested (F.  Luchetti, personal communication).   Additional
study to obtain a more accurate picture of the nutrient
budget for Topaz Lake is recommended.

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II.   LAKE AND DRAINAGE BASIN CHARACTERISTICS

          Lake and drainage basin characteristics  are  itemized below.

     Lake morphometry data were provided by James  B. Williams, Jr.

     (personal communication).   Tributary flow data were provided by

     the Nevada District Office of the U.S. Geological  Survey.

     Outlet drainage area includes the lake surface area.   The drainage

     area and flow of the Walker River is included in  the drainage area

     of Topaz Canal (A-l)  and Unnamed Canal (B-l) . Mean hydraulic

     retention time was obtained by dividing  the lake  volume by mean

     flow of the outlet.  Precipitation values are estimated by methods

     as outlined in National Eutrophication Survey (NES) Working Paper

     No. 175.  A table of metric/English conversions  is included as

     Appendix A.

     A.   Lake Morphometry:
                                     2
          1.   Surface area:  9.71 km .
          2.   Mean depth:  15.8 meters.
          3.   Maximum depth:  28.0 meters.
          4.   Volume:  154.418 x 106 m3.
          5.   Mean hydraulic retention time:   264 days.

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B.   Tributary and Outlet:
     (See Appendix B for flow data)

     1.    Tributaries -

                                             Drainage       Mean Flow
          Name                               area (km2)     (m3/sec)

          B-l Unnamed Canal                    1,048.9         6.75

          Minor tributaries and
          immediate drainage -                   21.4         0.06

                    Total                     1,070.3         6.81

     2.    Outlet - A-l Topaz Canal             1,080.0         6.77

C.   Precipitation:

     1.    Year of sampling:  26.0 cm.
     2.    Mean annual:  21.6 cm.

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III.  LAKE WATER QUALITY SUMMARY
          Topaz Lake was sampled three  times  during  the  open-water
     season of 1975 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 v).  During each  visit,
     depth-integrated samples were collected  from each station for
     chlorophyll o_ analysis and phytoplankton identification  and
     enumeration.   During the first and last  visits, 18.9-liter
     depth-Integrated samples were composited for algal  assays.
     Maximum depths sampled were 25.9 meters  at Station  01,  and
     23.8 meters at Station 02.  For a  more detailed explanation
     of NES methods, see NES Working Paper No.  175.
          The results obtained are presented  in full in  Appendix C
     and are summarized in III-A for waters at  the surface and at
     the maximum depth for each site.  Results  of the phytoplankton
     counts and chlorophyll ^determinations  are  included in  III-B.
     Results of the limiting nutrient study are presented in  III-C.

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TOPA7 RESERVOIR
STORE! CODE 3206
             PHYSICAL AND CHEMICAL CHARACTERISTICS
PARAMETER
TEMPERATURE (DEG
O.-l. 5 M DEPTH
"AX DEPTH**
DISSOLVED OXYGEN
O.-l.S M DEPTH
MAX DEPTH**
( 3/19/75
N* RANGE MEDIAN
CENT)
4
2
(MG/L)
4
?-

5.0- 5.4
4.8- 5.1

9.6- 10.0
9.4- 9.6

5.2
4.9

9.7
9.5
MAX
DEPTH
RANGE
(METERS) N*

n.o-
23.8-

0.0-
23.8-

1.5
24.4

1.5
24.4

4
2

4
2
( 7/ 1/75
S**» = 2
RANGE MEDIAN

12.9- 17.4
7.2- 7.2

8.6- 8.B
2.6- 6.0

14.8
7.2

8.7
4.3
MAX
DtPTH
RANGE
(METERS)

0.0-
15.2-

0.0-
15.2-

1.5
25.9

1.5
25.9
N*

4
2

4
2
( ll/ 5/75
S*«» = 2
RANGE MEDIAN

12.3- 12.5
11.4- 11.6

7.6- fl.?
0.4- 0.6

12.4
11.5

7.7
0.5
MAX
DEPTH
RANGE
(METERS)

0.0- 1.5
18.9- 21.0

0.0= 1.5
18.9- 21.0
CONDUCTIVITY (UMHO^)
O.-l.S M DEPTH
MAX DFPTH**
4
2
99.- 101.
100.- 101 .
ion.
101 .
0.0-
23.8-
1.5
24.4
4
2
75.- 100.
112.- 145.
87.
129.
0.0-
15.2-
1.5
25.9
4
2
97.- 101.
101.- 107.
100.
104.
0.0- 1.5
lfl.9- 21.0
PH (STANDARD UNITS)
O.-l.S M DEPTH
MAX DEPTH**
TOTAL ALKALINITY
O.-l.S M DEPTH
MAX DEPTH**
TOTAL P (MG/L)
O.-l .5 M DEPTH
MAX DEPTH'*
DISSOLVED ORTHO P
O.-l.S M DEPTH
MAX DEPTH**
N02+N03 (MG/L)
O.-l. 5 M DEPTH
MAX DEPTH**
AMMONIA (MG/L)
O.-l. 5 M DEPTH
MAX DEPTH**
KJELDAHL N (MG/L)
O.-l.S M DEPTH
MAX DEPTH**
4
?-
(MG/L)
4
2

4
2
(MG/L)
4
2

4
2

4
2

4
2
7.5- 7.9
7.8- 7.9

81.- 86.
83.- 88.

0.054-0.060
0.054-0.060

0.041-0.042
0.041-0.044

0.040-0.040
0.040-0.040

0.220-0.230
0.230-0.230

0.600-1.200
0.500-0.600
7.8
7.8

84.
BA.

0.055
O.OS7

0.041
0.042

0.040
0.040

0.2?0
O.?30

0.650
0.5SO
0.0-
23.8-

0.0-
23.8-

0.0-
23.8-

0.0-
23.8-

0.0-
23.8-

0.0-
23.8-

0.0-
23.8-
1.5
24.4

1.5
24.4

1.5
24.4

1.5
24.4

1.5
24.4

1.5
24.4

1.5
24.4
4
2

4
2

4
2

4
2

4
2

4
2

4
2
6.3- 8.8
7.5- 8.0

47.- 53.
82.- 88.

0.036-0.068
0.085-0.159

0.005-0.015
O.OSQ-0.116

0.020-0.030
0.030-0.050

0.020-0.520
0.190-0.420

0.200-0.500
o. 4oo-o. aoo
8.5
7.8

53.
85.

0.043
0.122

0.007
0.088

0.020
0.040

0.030
0.305

0.350
0.600
0.0-
15.2-

0.0-
15.2-

0.0-
15.2-

0.0-
15.2-

0.0-
15.2-

0.0-
15.2-

0.0-
15.2-
1.5
25.9

1.5
25.9

1.5
25.9

1.5
25.9

1.5
25.9

1.5
25.9

1.5
25.9
4
2

4
2

4
2

4
2

4
2

4
2

4
2
7.6- 7.R
7.3- 7.5

61.- 75.
60.- 71.

0.067-0.086
0.096-0.173

0.037-0.049
O.OH3-0.103

0.020-0.020
0.020-0.020

0.040-0.080
0.160-0.500

0.200-0.200
0.400-0.600
7.7
7.4

69.
66.

0.071
0.134

0.045
0.093

0.020
0.020

0.065
0.330

0.200
0.500
0.0- 1.5
18.9- 21.0

0.0- 1.5
18.9- 21.0

0.0- 1.5
18.9- 21.0

0.0- 1.5
18.9- 21.0

0.0- 1.5
18.9- 21.0

0.0- 1.5
18.9- 21.0

0.0- 1.5
18.9- 21.0
SECCHI DISC  (METER<:>
                            3.4-   4.3
3.8
1.8-  2."    2.1
                                    3.4-  3.7     3.5
                            N  =  NO.  OF  SAMPLES
                            MAXIMUM DEPTH SAMPLED AT EACH SITE
                            »  s  =  NO. OF SITES SAMPLED ON THI<: D4TE

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B.   Biological Characteristics:

     1.   Phytoplankton -

          Sampling
          Date

         03/19/75
         06/30/75
         07/01/75
         11/05/75
Dominant
Genera

1.  Centric diatom
2.  Fragilaria
3.  Dictyosphaerium
4.  Melosira
5.  Chroomonas?

    Other genera

         Total

1.  Fragilaria
2.  As ten'one 11 a
3.  Chroomonas?
4.  Aphanizomenon
5.  Cryptomonas

    Other genera

         Total

1.  Fragilaria
2.  Aphanizomenon
3.  Asterionella
4.  Chroomonas?
5.  Melosira

    Other genera

         Total

1.  Cryptomonas
2.  Fragilaria
3.  Staiirastrum
4.  Melosira
5.  Stephanodiscus

    Other genera

         Total
Algal
Units
Per ml

   198
   159
   119
   119
    79

	39

   713

  5,059
   670
   335
   274
    30

	32_

  6,400

  4,766
   801
   521
   320
   160

	80

  6,648

   224
   112
   112
    56
    19

	37

   560

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2.   Chlorophyll a_ -
     Sampling                 Station              Chlorophyll  a_
     Date                     Number               (yg/1)	

     03/19/75                   01                      3.2
                                02                      3.3

     06/30/75                   01                      9.4
                                02                      8.5

     11/05/75                   01                      9.6
                                02                     11.1

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                                  10
C.    Limiting Nutrient Study:

     1.    Autoclaved, filtered, and nutrient spiked -

                         Ortho P        Inorganic N    Maximum Yield
          Spike (mg/1)   Cone, (mg/1)   Cone,  (mg/1)   (mg/1-dry wt.)

          a.    03/19/75

          Control           0.035    '      0.208  "     ' '  1{  6.4 '  /;
          0.05 P           0.085          0.208             7.5
          0.05 P •«• 1.0 N   0.085          1.208            25.3
          1.00 N           0.035          1.208            11.5

          b.    11/05/75

          Control           0.055          0.180             8.3
          0.05 P           0.105          0.180             8.4
          0.05 P + 1.0 N   0.105          1.180            38.4
          1.00 N           0.055          1.180            23.2

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                                  11
2.   Discussion -
          The control  yields of the assay alga,  Selenastrum capri-
     cornutum*, indicate that the potential  for  primary productivity
     in Topaz Lake was high during the sample collection times
     (03/19/75, 11/05/75).   In both assays,  a significant increase
     in yield over that of the control occurred  when nitrogen was
     added alone and in combination with phosphorus, indicating
     nitrogen limitation.  Spikes of phosphorus  alone did not
     stimulate growth  significantly beyond control  yields.
          The mean N/P ratios in the lake data were 7/1 or less on
     the three sampling occasions further suggesting primary limi-
     tation by nitrogen (a mean N/P ratio of 14/1  or less generally
     reflects phosphorus limitation).
 *For  further  information regarding the algal assay test procedure
 and selection of test organisms, see U.S. EPA  (1971).

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                                  12
IV.   NUTRIENT LOADINGS
     (See Appendix D for data)
          For the determination  of nutrient  loadings,  the  Nevada  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 April,  May,  June and July when two samples  were
     collected.   Sampling was begun in November 1974,  and  was completed
     in November 1975.
          Through an interagency agreement,  stream flow estimates for
     the year of sampling and a  "normalized"  or average year were pro-
     vided by the Nevada District  Office of  the USGS for the tributary
     sites nearest the lake.
          In this report, nutrient loads for sampled tributaries  were
     determined  by using a modification of a USGS computer program for
     calculating stream loadings.   Nutrient  loads indicated  for tribu-
     taries are  those measured minus known point source loads,  if any.
          Nutrient loadings for  unsampled  "minor tributaries and
     immediate drainage" ("ZZ" of  USGS) were estimated  by  using the
     mean  annual  concentrations  in  Unnamed Canal,  California Creek and
     Slinkard Creek at Stations  B-l, C-l,  and D-l and mean annual ZZ
     flow.

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                                  13
A.   Waste Sources:
     1.   Known municipal - None
     2.   Known industrial - None
B.   Annual Total Phosphorus Loading - Average Year:
     1.   Inputs -
                                                            % of
          Source                             kg P/yr        total
          a.   Tributaries (nonpoint load) -
               B-l Unnamed Canal             12,825          97.3
          b.   Minor tributaries and immediate
               drainage  (nonpoint load) -       185           1.4
          c.   Known municipal STP's - None
          d.   Septic tanks* -                   <5          <0.1
          e.   Known industrial - None
          f.   Direct precipitation** -         170           1.3
                              Total          13,180         100.0%
     2.   Outputs - A-l Topaz Canal           6,195
     3.   Net annual P accumulation -         6,985
     *Estimate based on 1 lakeshore residence.
    **Estimated (See NES Working Paper No. 175).

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                                  14
C.   Annual Total Nitrogen Loading - Average Year:

     1.    Inputs -
                                                            % of
          Source                             kg N/yr        total

          a.   Tributaries (nonpoint load) -

               B-l Unnamed Canal              114,020         90.6

          b.   Minor tributaries and immediate
               drainage (nonpoint load) -      1,355          1.1

          c.   Known municipal STP's - None

          d.   Septic tanks* -                    10         <0.1

          e.   Known industrial - None

          f.   Direct precipitation** -       10,485          8.3

                              Total          125,870        100.0%

     2.    Outputs - A-l  Topaz  Canal           195,470

     3.    Net annual N export*** -            69,600
    *Estimate based on 1  lakeshore residence.
   **Estimated (See NES Working Paper No.  175).
  ***Export probably due to unknown sources and/or sampling error.

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                                  15
D.   Mean Annual Nonpoint Nutrient Export by Subdrainage Area:


                                               2              2
     Tributary                          kg P/km /yr    kg N/km /yr



     Unnamed Canal                           12             109



E.   Mean Nutrient Concentrations in Ungaged Streams:



                                        Mean Total P   Mean Total N

     Tributary                             (mg/1)         (mg/1)



     C-l California Creek                   0.115          0.900

     D-l Slinkard Creek                     0.123          0.715

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                                  16
F.    Yearly Loadings:
          In the following table, the existing phosphorus  annual
     loading is compared to the relationship proposed by Vollenweider
     (1975).  Essentially, his "eutrophic"  loading is that at which
     the receiving waters would become eutrophic or remain eutrophic;
     his "oligotrophic"  loading is that which would result in the
     receiving water remaining oligotrophic or becoming oligotrophic
     if morphometry permitted.  A "mesotrophic" loading would be
     considered one between "eutrophic" and "oligotrophic".
          Note that Vollenweider's model may not apply to  lakes with
     short hydraulic retention times or in  which light penetration is
     severely restricted by high concentrations of suspended solids
     in the surface waters.
                             Total  Yearly
                          Phosphorus Loading
                               (9/m2/yr)
     Estimated loading for Topaz Lake                            1.36
     Vollenweider's "eutrophic" loading                          0.90
     Vollenweider's "oligotrophic" loading                       0.45

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                                   17
V.   LITERATURE REVIEWED

     Carson River Basin Council of Governments.  1974.  Regional Water
       Quality Plan, Phase I, Existing Conditions, Walker River Basin
       Carson City, Nevada.

     Luchetti, F.  1977.  Personal communication (septic tanks).
       Nevada Environmental Protection Service, Carson City, Nevada.

     U.S. Environmental Protection Agency.  1971.  Algal Assay
       Procedure Bottle Test.  National Eutrophication Research
       Program, Corvallis, Oregon.

     U.S. Environmental Protection Agency.  1975.  National Eutrophica-
       tion Survey Methods 1973-1976.  Working Paper No. 175.  National
       Environmental Research Center, Las Vegas, Nevada, and Pacific
       Northwest Environmental Research Laboratory, Corvallis, Oregon.

     Vollenweider, R. A.  1975.  Input-Output Models With Special
       Reference to the Phosphorus Loading Concept in Limnology.
       Schweiz. Z. Hydrol.  37:53-84.

     Williams, James B., Jr.   1974.  Personal Communication (lake
       morphometry).  Department of Human Resources, Carson City, Nevada.

-------
          18
    APPENDIX A



CONVERSION FACTORS

-------
                CONVERSION FACTORS





Hectares x 2.471 = acres



Kilometers x 0.6214 = miles



Meters x 3.281 = feet



Cubic meters x 8.107 x 10"  = acre/feet



Square kilometers x 0.3861 = square miles



Cubic motors/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 B



TRIBUTARY FLOW DATA

-------
                                   TRIBUTARY FLOW INFORMATION FOR NEVADA
                                                                               1/21/77
LAKE CODE 3206
       TOPAZ  LAKE
     TOTAL DRAINAGE AREA OF LAKFfSQ KM)
                              1080.0
          SUB-DRAINAGE
TRIBUTARY  AREA(SQ KM»
              JAN
                      FEB
3206A1
320681
3206ZZ
1080.0
1048.9
  31.1
 0.93    1.42
 3.62    4.98
0.028   0.031
                                          MAR
 3.94
0.037
  APR

 7.02
 5.52
0.082
  MAY

16.99
17.78
0.161
                                        NORMALIZED FLOWS(CMS)
                                          JUN     JUL     AUG
21.04
23.70
0.210
15.01
10.51
0.088
 8.64
 2.35
0.031
  SEP

 4.73
 1.10
0.025
  OCT

 1.84
 1.47
0.017
                                                                  NOV
 ?.66
0.020
                                                                                                      DEC
                                                                                                             MEAN
 0.68    6.77
 3.34    6.75
0.023   0.063
                        TOTAL DRAINAGE AREA OF LAKE
                        SUM OF SUB-DRAINAGE AREAS
                                             1080.0
                                             1080.0
     MEAN MONTHLY FLOWS AND DAILY FLOWS(CMS)

TRIBUTARY   MONTH   YEAR    MEAN FLOW  DAY         FLOW  DAY

3206A1
3206B1
11
12
1
2
3
4
5
6
7
8
9
10
11
11
12
1
2
3
4
5
6
7
8
9
10
11
74
74
75
75
75
75
75
75
75
75
75
75
75
74
74
75
75
75
75
75
75
75
75
75
75
75
                                                                   SUMMARY
                                                      TOTAL FLOW IN
                                                      TOTAL FLOW OUT
                                                           81.74
                                                           80.93
                                                         FLOW  DAY
                                                               FLOW
0.850
0.793
0.736
0.680
0.708
0.765
11.327
28.317
19.822
14.158
5.663
2.832
0.0
2.832
2.690
2.690
2.549
2.832
3.115
16.990
39.644
16.990
2.832
3.681
4.248
0.0
IS
16
20
1ft
19
4
7
2
3

2?

3
IS
1*.
20
18
19
4
7
?
1

2?

3
0.906
0.793
0.765
0.623
0.708
0.736
7.079
31.149
22.653

5.663

2.265
2.888
2.662
2.662
2.407
3.030
3.058
8.495
45.307
25.485

4.248

5.663





22
21
30
16









22
21
30
16









0.765
25.485
22.653
18.406









3.256
31.149
28.317
19.822





-------
        APPENDIX C



PHYSICAL AND CHEMICAL DATA

-------
STORET RETRIEVAL DATE 77/01/36
NATL EUT90PHICATION SURVEY
EPA-LAS VEGAS
/TYPA/AMBNT/LAKE
00010
DATE
FROM
TO
75/03/19




75/07/01






75/11/05




TIME
OF
DAY
1
1
1
1
1
09
09
09
09
09
09
09
15
15
15
15
15


55
55
55
55
55
50
50
50
50
50
50
50
00
00
00
00
00
DEPTH

FEET
0000
0005
0025
0050
0080
0000
0005
0015
0025
0040
0065
0085
0000
0005
0025
0045
0069
WATER
TEMP
CENT
5
5
5
5
5
17
16
14
12
10
7
7
12
12
12
12
11



.4
.4
.3
.2
.1
.4
.6
.5
.9
.4
.7
.2
.5
.4
.2
.2
.4
        330601
       36 41 02.0 119 31 58.0 3
       TOPAZ RESERVOIR
       32005   NEVADA
                                                                                          150191
11EPALES

00300
DO

MG/L
9.8
10.0
9.4
10.0
9.6
8.6
8.6
8.0
7.4
7.0
4.6
2.6
8.2
7.6
7.8
5.8
0.4

00077
TRANSP
SECCHI
INCHES
132




72






144





00094
CNDUCTVY
FIELD
MICROMHO
101
100
101
99
100
100
99
91
91
100
142
145
101
101
99
99
107
0084
00400
PH

SU
7.50
7.65
7.70
7.80
7.80
8.80
8.80
8.40
8.00
7.80
7.60
7.50
7.70
7.80
7.65
7.60
7.30
04001002
FEET DEPTH CLASS
00410
T ALK
CAC03
MG/L
86
84
85
83
83
53
53
53
55
64
87
88
74
75
73
78
71
00610
NH3-N
TOTAL
MG/L
0.230
0.220
ff.220
0.210
0.230
0.030
0.520
0.020
0.040
0.100
0.290
0.420
0.040
0.050
0.060
0.080
0.500
00
00625
TOT KJEL
N
MG/L
1.200
0.600
0.600
0.600
0.500
0.400
0.300
0.300
0.300
0.400
0.600
0.800
0.200
0.200
0.200
0.200
0.600
                                                                                                      00630     00671
                                                                                                    N02&.N03   PHOS-DIS
                                                                                                    N-TOTAL    ORTHO
                                                                                                      MG/L     MG/L P
                                                                                                       0.040
                                                                                                       0.040
                                                                                                       0.040
                                                                                                       0.040
                                                                                                       0.040
                                                                                                       0.020K
                                                                                                       0.020K
                                                                                                       0.020K
                                                                                                       0.020
                                                                                                       0.050
                                                                                                       0.050
                                                                                                       0.030
                                                                                                       0.020K
                                                                                                       0.020K
                                                                                                       0.020K
                                                                                                       0.020K
                                                                                                       0.020K
                                                        0.041
                                                        0.041
                                                        0.041
                                                        0.040
                                                        0.041
                                                        0.005
                                                        0.008
                                                        0.008
                                                        0.015
                                                        0.038
                                                        0.079
                                                        0.118
                                                        0.037
                                                        0.043
                                                        0.049
                                                        0.050
                                                        0.103
  DATE
  FROM
   TO

75/03/19
75/07/01
75/11/05

TIME DEPTH
OF
DAY FEET
11 55 0000
11 55 0005
11 55 0025
11 55 0050
11 55 0080
09 50 0000
09 50 0005
09 50 0015
09 50 0025
09 50 0040
09 50 0065
09 50 0085
15 00 0000
15 00 0005
15 00 0025
15 00 0045
15 00 0069
00665 32217
PHOS-TOT CHLRPHYL
A
MG/L P UG/L
0.060 3.2
0.057
0.056
0.054
0.054
0.036 9.4
0.068
0.036
0.042
0.050
0.095
0.159
0.071 9.6
0.067
0.058
0.066
0.173
00031
INCDT LT
REMNING
PERCENT

















K VALUE KNOWN TO BE LESS
    THAN INDICATED

-------
STORET RETRIEVAL DATE 77/01/26
NATL EUTROPHICATION SURVEY
EPA-UAS VEGAS
/TYPA/AMBNT/LAKE

DATE
FROM
TO
75/03/19




75/06/30




75/11/05





TIME
OF
DAY
12 30
12 30
12 30
12 30
12 30
14 20
14 20
14 20
14 20
14 20
15 25
15 25
15 25
15 25
15 25

DEPTH

FEET
0000
0005
0019
0050
0078
0000
0005
0015
0035
0050
0000
0005
0022
0045
0062
00010
*ATER
TEMP
CENT
5.0
5.0
5.0
4.9
4.8
13.1
12.9
12.9
10.4
7.2
12.5
12.3
12.2
12.1
11.6
 320603
38 40 18.0 119 32 17.0 3
TOPAZ RESERVOIR
32005   NEVADA
                                                                                           150191
11EPALES
04001002
0082 FEET DEPTH CLASS
00300
DO

M6/L
9.6
9.6
9.4
9.8
9.4
8.8
8.8
7.6
7.4
6.0
7.6
7.8
7.8
4.2
0.6
00077
TRANSP
SECCHI
INCHES
168




96




132




00094
CNDUCTVY
FIELD
MICROMHO
99
99
100
99
101
75
75
79
77
112
97
99
97
99
101
00400
PH

SU
7.90
7.90
7.90
8.00
7.90
8.30
8.30
7.90
7.70
8.00
7.60
7.70
7.60
7.50
7.50
00410
T ALK
CAC03
MG/L
84
81
81
83
88
47
53
54
60
82
63
61
61
59
60
00610
NH3-N
TOTAL
MG/L
0.220
0.220
0.220
0.220
0.230
0.020
0.030
0.060
0.080
0.190
0.080
O.OflO
0.080
0.120
0.160
00
00625
TOT KJEL
M
MG/L
0.700
0.600
0.600
0.600
0.600
0.500
0.200
0.200
0.300
0.400
0.200
0.200
0.200
0.200
0.400
                                                                                                       00630     00671
                                                                                                     N02&N03   PHOS-DIS
                                                                                                     N-TOTAL    OPTHO
                                                                                                       MG/L     MG/L P
                                                                                                        0.040
                                                                                                        0.040
                                                                                                        0.040
                                                                                                        0.040
                                                                                                        0.040
                                                                                                        0.020K
                                                                                                        0.030
                                                                                                        0.020
                                                                                                        0.030
                                                                                                        0.050
                                                                                                        0.020
                                                                                                        0.020
                                                                                                        0.020
                                                                                                        0.020
                                                 0.042
                                                 0.041
                                                 0.042
                                                 0.044
                                                 0.044
                                                 0.007
                                                 0.015
                                                 0.020
                                                 0.025
                                                 0.059
                                                 0.049
                                                 0.048
                                                 0.047
                                                 0.053
                                                 0.083
DATE
FROM
TO
75/03/19




75/06/30




75/11/05




00665 32217 00031
TIME DEPTH PHOS-TOT CHLRPHYL INCDT LT
OF A REMNING
DAY FEET
12
12
12
12
12
14
14
14
14
14
15
15
15
15
15
30
30
30
30
30
20
20
20
20
20
25
25
25
25
25
0000
0005
0019
0050
0078
0000
0005
0015
0035
0050
0000
0005
0022
0045
0062
MG/L P
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
.054
.054
.056
.053
.060
.038
.049
.050
.047
.085
.086
.071
.082
.071
.096
UG/L PERCENT
3.3




8.5




11.1




                                                              K VALUE KNOWN TO BE LESS
                                                                  THAN INDICATED

-------
       APPENDIX D

TRIBUTARY AND WASTEWATER
  TREATMENT PLANT DATA

-------
STOwtT RETRIEVAL  OATE  77/U1/2?
NATL EUTROPHICATION  SURVEY
EPA- LAS VEGAS
/TYPA/AMBNT/STQEAM
  DATE   TIME  DEPTH N02J.N03
  FROM    OF
   TO    DAY   FEET
74/11/1S
74/12/16
75/01/20
75/02/18
75/03/19
75/04/04
75/04/22
75/05/07
75/05/21
75/06/02
75/06/30
75/07/03
75/07/16
75/09/22
75/11/03
10
03
10
11
13
11
10
10
10
16
10
11
1 0
11
14
15
30
40
05
05
45
30
10
30
45
45
on
50
00
50
 3206A1
38 41 4-5.0  119 30 20.0 4
Topaz Canal
32       15  TOPAZ LAKE
0/TOPAZ  LAKE              150191
bNK SAMP OFF  SEC HD 3 M E OF JCT  HWY  395
HEPALES            04001004
 0000 FEET   DEPTH  CLASS 00
10630
!f,N03
OTAL
IG/L
0.016
0.032
0.03?
0.035
0.050
0.050
0.005
0.015
0.025
0.015
0.005
0.010
0.015
0.005
0.025
00635
TOT KJEL
N
MG/L
0.700
0.700
0.500
1.750
0.950
1.050
1.000
0.500
1.450
0.200
1.000
0.450
1.150
0.300
0.700
00610
NH3-N
TOTAL
MG/L
0.155
0.144
o.n6
0.460
0.145
0.105
0.020
0.050
0.075
0.005
0.015
0.010
0.020
0.015
0.035
00671
PHOS-DIS
0"THO
MG/L P
0.040
0.040
0.035
0.040
0.035
0.030
0.015
0.015
0.0?5
0.010
0.010
0.010
0.010
0.005*
0.040
006t>5
PMOS-TOT

MG/L H
0.060
0.060
0.070
0.065
0.060
0.030
0.030
0.015
0.040
0.020
0.030
0.015
0.020
0.040
0.050
     K VALUE KNOWN TO BE LESS
         THAN INDICATED

-------
' &TL HJT
   - UAS VEGAS
/TYPA/AMBNT/STREAM
              FEET
38 38 10.0 11V 30 25.0 4
 Unnamed Canal
32      15 TOPAZ LAKE
T/TOPAZ LAKE
UNMPRVO RD 8ROG 1.7 MI
11EPALES
 0000 FEET  DEPTH
      150191
    S OF TOPAZ PO
 04001004
CLASS 00
DATE
FROM
TO
74/11/1S
74/12/16
75/01/20
75/02/18
75/03/19
75/04/04
75/04/22
75/05/07
75/05/21
75/06/0?
75/06/30
75/07/03
75/07/16
75/OV/22
75/11/03
TIME C
OF
OAY f
12 30
09 30
11 45
11 55
14 15
13 30
11 30
10 50
11 00
11 30
11 20
11 30
11 30
11 50
15 46
00630
N02(s,N03
N-TOTAL
M6/L
0.016
0.05*
0.092
0.070
0.025
0.042
0.015
0.0?5
0.085
0.055
0.010
O.Oln
o.ons
0.030
0.025
00625
TOT KJEL
N
MG/L
0.100
0.100K
0.500
0.950
0.350
0.750
0.300
1.000
0.900
0.250
0.650
0.300
0.200
0.475
0.200
00610
NH3-N
TOTAL
MG/L
0.0?0
0.056
0.096
0.070
0.095
0.015
0.015
0.020
0.030
0.015
0.015
0.015
0.010
0.010
0.010
00671
PHOS-DIS
ORTHO
MG/L P
0.020
0.024
0.030
0.020
0.025
0.022
0.020
0.0*5
0.025
0.020
0.020
0.025
0.015
0.045
0.025
00665
PMOS-TOT

MG/L P
0.030
0.030
0.040
0.050
0.070
0.030
0.060
0.090
O.OflO
0.130
0.080
0.030
0.040
0.100
0.040

-------
STORET RETRIEVAL  LtATE  77/01/22
NATL F.UTHOPHICATION  SURVEY
EPA- LAS VEGAS
/TYPA/AMBNT/STREA~<
  DATE   TIME DEPTH  N02S.N03
  FROM    OF
   TO    DAY  FEET
74/11/15
74/12/16
75/01/20
75/02/18
75/03/19
75/04/04
75/04/22
75/05/07
75/05/21
75/06/02
75/06/30
75/07/03
75/07/16
75/0*/22
75/11/03
10
09
11
11
13
12
11
10
10
11
11
11
11
11
15
4b
00
00
?5
25
30
00
30
45
on
00
05
05
20
05
 3206C1
38 40 50.0  119  32  50.0 4
CALIFORNIA  CREEK
32      15  TOPAZ  LAKE
T/TOPAZ LAKE
US HWY 395  8POG .5 M S
11EPALES
 0000 FEET  DEPTH
      150191
    OF CA NV  STATE  LN
 0400100*
CLASS 00
0630

-------
•'«.rt
   - LAS  VEGAS
                 1 )'•
/TYPA/A.-16NT/STREAM
  DATE   TIME  DEPTH N02f,N03
  FRO*    OF         N-
   TO    DAY   FEET
74/11/15
74/12/16
75/01/20
75/02/18
75/03/19
75/04/04
75/04/22
75/05/07
75/05/21
75/06/02
75/06/30
75/07/03
75/07/16
75/OV/22
75/11/03
11
09
11
11
13
13
11
10
10
11
11
11
11
11
15
15
15
20
40
15
05
10
40
50
15
10
10
15
30
25
 320601
38 38 30.0  119  31  50.0 4
SLINKARD CREEK
32      15  TOPAZ LAKE
T/TOPAZ LAKE              150191
8NK SAM ON  H*Y  89  .1 MI w QF H«Y  395 JCT
11EPALES             0400100*
 0000 FEET  DEPTH   CLASS 00
10630
!f,N03
•QTAL
IG/L
0.00°
0 . 0 ft o
0.11?
0.100
0.050
0.190
0.075
0.045
0.070
0.040
0.010
0.015
0.015
0.005
0.005
00625
TOT KJEL
N
MG/L
0.200
0.200
0.100
1.4bO
0.200
1.650
0.600
0.800
2.50'0
0.150
0.550
0.450
0.350
0.400
0. 300
00610
MH3-N
TOTAL
MG/L
0.050
0.016
0.008K
0.260
0.020
0.015
0.010
0.065
0.030
0.025
0.010
D.025
0.015
n.oio
0.005K
00671
PHOS-DIS
OUTMO
MG/L P
0.070
0.060
0.065
0.06b
0.065
0.075
0.060
0.065
0. OtiO
0.105
0.14Q
0.130
0.160
0.110
0.090
0066S
PhOS-TOT

MG/L P
0.085
0.080
0.080
0.120
0.110
0.080
0.110
0.100
0.230
0.110
0.155
0.140
0.200
0.1 JO
0.1 10
        K VALUE KNOWN TO BE LESS
             THAN INDICATED

-------
                              APPENDIX E

                     PARAMETRIC RANKINGS OF LAKES
                        SAMPLED BY NES IN 1975

                            STATE OF NEVADA
     Mean or median values for six of the key parameters evaluated
in establishing the trophic conditions of Nevada lakes, sampled are
presented to allow direct comparison of the ranking,  by parameter,
of each lake relative to the others.  Median total  phosphorus, median
inorganic nitrogen and median dissolved orthophosphorus levels are
expressed in mg/1. Chlorophyll ^values are expressed in yg/1.  To
maintain consistent rank order with the preceding parameters,  the
mean Secchi disc depth, in inches, is subtracted from 500.   Similarly,
minimum dissolved oxygen values are subtracted from 15 to create
table entries.

-------
LAKE; DATA TO BE USED IN RANKINGS
LAKE
CODE   LAKE NAME
3201   LAKE HEAD
3202   LAHO.NTA.N RESERVOIR
3204   RYE PATCH RESERVOIR
3?05   LAKE TAHOE
32C6   TOPAZ RESERVOIR
2207   UPPER PAKRANGAT LAKE
3203   WASHOE LAKE
3209   WILD HORSE RESERVOIR
3210   .WILSON RESERVOIR
3211   WALKER LAKE
MEDIAN
TOTAL P
0.016
0.198
0.094
0.005
0.057
0.173
0.403
0.114
0.049
0.602
MEDIAN
INORG N
0.340
0.350
0.050
0.040
0.165
0.125
0.135
0.320
0.120
0.080
500-
MEAN SEC
266.565
472.033
467.750
-3.269
376.000
470.000
494.555
439.400
197.333
405.333
MEAN
CHLORA
3.111
4.608
4.938
0.571
7.517
—
11.633
75.530
10.033
3.422
15-
HIN DO
11.400
10.400
10.000
10.200
14.600
3.600
7.200
14.600
11.400
15.000
MEDIAN
DISS ORTHO P
0.005
0.148
0.039
0.003
O.G41 .
0.025
0.268
0.065
0.016
0.574

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PERCENT OF LAKES WITH HIGHER VALUES (NUMBER OF LAKES WITH HIGHER VALUES)
LAK€
CODE   LAKE. NAME.
3201   LAKE MEAD
3202   LAHONTAN RESERVOIR
3204   RYE PATCH RESERVOIR
3205   LAKE TAHOE
3206   TOPAZ RESERVOIR
3207   UPPER PAHRANAGAT LAKE
3208   WASHOE LAKE
3209   WILD HORSE RESERVOIR
3210   WILSON RESERVOIR
3211 '  WALKER LAKE
MEDIAN
TOTAL P
89 (
22 (
56 (
100 (
67 (
33 (
11 (
44 (
73 (
0 (
8)
2)
5)
9)
6)
3)
1)
4)
7)
0)
MEDIAN
INORG N
11 (
0 (
89 (
100 (
33 (
56 (
44 (
22 C
67 (
78 (
1)
0)
8)
9)
3)
5)
4)
2)
6)
7)
500-
MEAN SEC
78 (
22 1
44 (
100 (
67 (
33 (
0 (
11 (
89 (
56 (
7)
2)
4)
9)
6)
3)
0)
1)
8)
5)
t'.EAM
CHLORA
88 (
63 (
50 (
100 (
38 (
	
13 (
0 (
25 (
75 (
7)
5)
4)
8)
3)

1)
0)
2)
6)
15-
MIN DO
39 (
56 C
78 (
67 (
17 (
89 (
100 (
17 (
39 (
0 (
3)
5)
7)
6)
1)
8)
9)
1)
3)
0)
MEDIAN
DISS ORTHO f
89 (
22 ( .
56 (
100 (
44 (
67 (
11 (
33 (
78 (
o C
8)
2)
5)
9)
4)
.6>
1)
3)
7)
0)

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