U.S. ENVIRONMENTAL PROTECTION AGENCY
               NATIONAL EUTROPHICATION SURVEY
                        WORKING PAPER SERIES
                                               REPORT
                                                 ON
                                          DWORSHAK RESERVOIR
                                           CLEARWA7ER COUNTY
                                                IDAHO
                                             EPA REGION X
                                         WORKING PAPER No, 779
     CORVALLIS ENVIRONMENTAL RESEARCH LABORATORY - CORVALLIS, OREGON
                                 and
    ENVIRONMENTAL MONITORING & SUPPORT LABORATORY - LAS VEGAS, NEVADA
•&G.P.O. 699-440

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                                 REPORT
                                   ON
                           DWQRSHAK RESERVOIR
                            CLEARWATER COUNTY
                                  IDAHO
                              EPA REGION X
                          WORKING PAPER No,  779
     WITH THE COOPERATION OF THE
IDAHO DEPARTMENT OF HEALTH AND WELFARE
                AND THE
         IDAHO NATIONAL GUARD
              JULY, 1977

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        REPORT ON DWORSHAK RESERVOIR
          CLEARWATER COUNTY, IDAHO
                EPA REGION X

                     by
       National Eutrophication 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. 779
     OFFICE OF RESEARCH AND DEVELOPMENT
    U.S. ENVIRONMENTAL PROTECTION AGENCY
                  July 1977

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                               CONTENTS

                                                       Page
Foreword                                                i i
List of Idaho 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                                18
 VI. Appendices                                         19

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                                  11
                               FOREWORD
     The National  Eutrophicatlon Survey was Initiated  1n  1972  1n
response to an Administration commitment to Investigate the  nation-
wide threat of accelerated eutrophlcatlon 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 eutrophlcatlon 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)L clean lakes [§314(a,bj], and water quality  monitoring
[§106 and §305(b)] activities mandated by the Federal  Water
Pollution Control  Act Amendments of 1972.

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                                  111
     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 refine-
ment 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 Idaho Department of Health
and Welfare for professional involvement, to the Idaho National
Guard for conducting the tributary sampling phase of the Survey,
and to those Idaho wastewater treatment plant operators who pro-
vided effluent samples and flow data.

     The staff of the State of Idaho Department of Health and
Welfare, Division of Environment, provided invaluable lake docu-
mentation and counsel during the Survey, reviewed the preliminary
reports and provided critiques most useful in the preparation of
this Working Paper Series.

     Major General James S. Brooks, Adjutant General  of Idaho, and
Project Officer Major Vestal L. Baker, who directed the volunteer
efforts of the Idaho National Guardsmen, are also gratefully
acknowledged for their assistance to the Survey.

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                                 IV
                    NATIONAL EUTROPHICATION SURVEY
                              STUDY LAKES
                            STATE OF IDAHO
LAKE NAME
American Falls Reservoir
Cascade Reservoir
Coeur d'Alene Lake
Dworshak Reservoir
Hauser Lake
Hayden Lake
Island Park Reservoir
Lake Lowell (Deer Flat Reservoir)
Magic Reservoir
Palisades Reservoir
Payette Lake
Lower Twin Lake
Upper Twin Lake
    COUNTY
Bannock, Bingham, Power
Valley
Benewah, Kootenai
Clearwater
Kootenai
Kootenai
Fremont
Canyon
Blaine, Camas
Bonneville (Lincoln in WY)
Valley
Kootenai
Kootenai

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                                                       DWORSHAK  RESERVOIR
                                                         <8>  Tributary Sampling Site
                                                         X   Lake Sampling Site:
                                                             Sewage Treatment Facility
                                                          ^Drainage Area Boundary
Map Location
                           CWORSHAK
                           RESERVOIR

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                  REPORT ON DWORSHAK RESERVOIR,  IDAHO
                            STORE! NO.  1604
I.    CONCLUSIONS
     A.    Trophic Condition:*
               Based upon Survey data and field  observations  Dworshak
          Reservoir is  considered oligotrophic.   Chlorophyll  a_ values
          ranged from 0.5 yg/1  to 6.7 yg/1  in the lake with a mean  of
          2.4 yg/1.  Potential  for primary production as  measured by
          algal  assay control yields was  low. Of the 13  Idaho lakes
          sampled in 1975, 11 had higher  median  total phosphorus, 1
          had higher median inorganic nitrogen and 5 had  higher median
          orthophosphorus levels than Dworshak Reservoir.
               Field limnologists reported Dworshak Reservoir was a
          clean and beautiful lake.  The  Idaho Department of  Water
          Resources et al. (1975) has noted that the lake is  of high
          water quality and low productivity, but that it will be a
          future site for heavy subdivision and  recreational  develop-
          ment, and should be watched closely for any deleterious
          changes.
     *See Appendix E.

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B.    Rate-Limiting Nutrient:
          The algal assay results indicate Dworshak Reservoir was limited
     by available phosphorus  at the times the samples were collected
     (04/07/75, 09/11/75).  The reservoir data suggest primary limitation
     by nitrogen on all  three sampling occasions.
C.    Nutrient Controllability:
     1.   Point Sources  -
               During the sampling year point sources were estimated to
          contribute only 0.4% of the total phosphorus loading to Dworshak
          Reservoir.  The towns of Headquarters and Elk River each con-
          tributed 0.2%  of the total phosphorus load.
               The annual phosphorus loading to Dworshak Reservoir of
                    o
          1.50 g P/m /yr is less than Vollenweider's (1975) proposed
          loading for "eutrophic" lakes but greater than his proposed
          "oligotrophic" level  on the basis of lake mean depth and
          hydraulic retention time.  Any future nutrient inputs to the
          lake should be carefully evaluated as to their effect on the
          high water quality  of the reservoir.
     2.   Nonpoint Sources  -
               Nonpoint  sources, including precipitation, were found to
          contribute 99.6% of the total phosphorus loading to Dworshak
          Reservoir during  the sampling year.  The North Fork Clearwater
          River contributed 53.4% of the total phosphorus load, the Little

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North Fork Clearwater River contributed 10.4%, and ungaged drainage
areas were estimated to have contributed 19.3%.  The Idaho Depart-
ment of Health and Welfare has also indicated that nutrient con-
tributions to the lake can be expected from bank instability and
associated slumping resulting from fluctuations of the reservoir
surface elevation (A.E. Murrey, personal communication).
     The Elks Creek and Reeds Creek had slightly higher annual
phosphorus nutrient exports than would be expected from strictly
nonpoint contributions (Section IV-D).  The Idaho Department of
Water Resources, et al. (1975) report that both of these creeks
are effected by upstream sewage and mining contributions, and the
U.S. Army District Engineer (1974) states that man-related non-
point contributions, such as agricultural runoff, are insig-
nificant in terms of their effect on water quality in the reservoir.
Additional investigation is needed to determine the extent of
these upstream mining and sewage sources before any recommen-
dations on their controllability can be made.

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II.   LAKE AND DRAINAGE BASIN CHARACTERISTICS
          Lake and drainage basin characteristics  are  itemized  below.
     Lake surface area, mean and maximum depth  were provided  by Herman
     Ray (personal communication).   Tributary flow data  were  provided
     by the Idaho District Office of the U.S. Geological  Survey (USGS).
     Outlet drainage area includes  the lake surface area.   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:  76.89 km.
          2.    Mean depth:  55.5 meters.
          3.    Maximum depth:   ? meters.
          4.    Volume:   4,267.875 x 10& m3.
          5.    Mean hydraulic retention time:  305 days.

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

     1.   Tributaries -

                                        Drainage,,      Mean flow
          Name                          area (km )     (m
          A-2 North Fork Clearwater River  3,522.4       106.92
          B-l Elk Creek                      240.4         7.30
          F-l Reeds Creek                    161.6         4.90
          G-l Breakfast Creek                334.1        11.00
          H-l Little North Fork              678.6        23.00
               Clearwater River

          Minor tributaries and
          immediate drainage -             1 ,306.2        43.66

                    Totals                 6,243.3       196.78

     2.   Outlet - A-l Clearwater River    6,319.6       161.71

C.   Precipitation:

     1.   Year of sampling:  64.9 cm.
     2.   Mean annual :  66.2 cm.

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III.  LAKE WATER QUALITY SUMMARY
          Dworshak Reservoir 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
     five 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 a_ analysis  and  phyto-
     plankton identification and enumeration.   During the first  and last
     visits, 18.9-liter depth-integrated samples were composited for  algal
     assays.  The maximum depth sampled at all lake stations was 64.0
     meters (the maximum line depth on the helicopter sampling probe).
     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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DWORSHAK
STOPET CODE  1604
                                                     PHYSICAL AND CHEMICAL CHARACTERISTICS

                                  (  4/ 7/75 )                         (  7/23/75  )
                                              *AX                                 MAX
                                 S*«» =  s    DEPTH                  S»*» =  5    DEPTH
                                              "iMGF                               RANGE
                                 E    MEDIAN  (METEP-S)    N»     HANGE    MEDIAN  (METERS)
                                                                                              N*
                                                                                                          (   9/11/75  )
                                                                                                                       MAX
                                                                                                          5»««  =   5     DEPTH
                                                                                                                       RANGE
                                                                                                     RANGE     MEDIAN  (METERS)
TEMPERATURE (OEG CF>;T)
O.-l.c M DEPTH        s    2.7-  4.5
MAX DEPTH**           4    ?.5-  4.2
4.0   0.0-  1.5
3.6  33.5- 64.0
                                                              21.4- 24.2
                   0.0-  1.5  10   15.4- 16.6    16.0    0.0-   1.5
DISSOLVED OXYGEN  (^G/D
O.-l.S M DEPTH        9
WAX DEPTH**           5

CONDUCTIVITY (IIMHOS)
O.-l.S M DEPTH       10
MAX DEPTH**           5

PH (STANDARD UNITS)
O.-l.c. M DEPTH       10
MAX DEPTH**           S

TOTAL ALKALINITY  (*-G/L)
O.-l.S M DEPTH       10
MAX DEPTH**           5
                          10.6- ll.y   11. if
                           3.P- 11.4   11.0
                           !"<.-  25.
      0.0-  1.5  10
     i3.5- 64.0   5
      0.0-  1.5  10
     33.5- 64.0   5
                                                               •i.O-  5.2    5.1  53.3- 53.3
7.8-  8.8    8.4   0.0-  1.5  10
9.4- 10.8   10.4  53.3- 53.3   5
                           6.7-  7.1
                           6.7-  7.0
                           12.-  22.
                           17.-  23.
7.0   0.0-  1.5  10
6.8  '33.5- 64.0   S
19.   0.0-  1.5  10
17.  33.5- 6a.O   5
30.-  34.
15.-  20.
7.3-  8.6
6.9-  8.4
10.-  28.
12.-  29.
30.   0.0-  1.5  10
16.  53.3- 53.3   5
8.0   0.0-  1.5  10
7.1  53.3- 53.3   5
16.   0.0-  1.5  10
17.  53.3- 53.3   5
                                                                                                    1.9-   ?.?
                       8.2-  9.4
                       9.0- 10.2
16.-  27.
 1.-   9.
6.6-  7.2
6.4-  6.6
10.-  30.
14.-  27.
                                                 2.1   64.0-  64.0
             A.9   0.0-   1.5
             9.6  64.0- 64.0
21.   0.0-  1.5
 6.  64.0- 64.0
6.7   0.0-  1.5
6.6  64.0- 64.0
15.   0.0-  1.5
21.  64.0- 64.0
TOTAL P (MG/L)
O.-l.S M DEPTH
MAX DEPTH**
                     10  0.013-0.028  0.016   0.0-  1.5  10  0.00^-0.014  0.010   0.0-  1.5  10  0.009-0.016   0.010    0.0-  1.5
                      5  0.015-0.034  O.Oie  J3.b- 64.0   5  0.007-0.010  0.008  53.3- 53.3   5  0.010-0.014   0.011   64.0- 64.0
DISSOLVED ORTHO P  (MG/D
O.-l.S M DEPTH
MAX DEPTH**

N02»N03 (MG/L)
O.-l.S M PEPTH
    DEPTH**
AMMONIA (MG/L)
O.-l.S M DEPTH
MAX DEPTH**

KJELD«HL N (MG/LI
0.-1.5 M DEPTH
MAX DEPTH**

SECCHI DISC
                     10  0.004-0.013  0.009   0.0-  1.5  10  0.004-0.017  0.011   0.0-  1.5  10  0.002-0.004   0.003    0.0-  1.5
                      5  0.006-0.012  0.007  33.5- 64.0   5  0.013-0.014  0.013  53.3- 53.3   5  0.005-0.008   0.006   64.0- 64.0


                     10  O.OSO-0.080  0.070   0.0-  1.5  10  0.020-0.030  0.020   0.0-  1.5  10  0.020-0.020   0.020    0.0-  1.5
                      S  0.060-0.110  0.070  33.5- 64.0   5  0.060-0.090  0.070  53.3- 53.3   5  0.040-0.080   0.060   64.0- 64.0


                     10  0.020-0.030  0.0?0   0.0-  1.5  10  0.020-0.030  0.020   0.0-  1.5  10  0.020-0.020   0.020    0.0-  1.5
                      5  0.080-0.030  O.n?0  33.5- 64.0   5  0.020-0.020  0.020  53.3- 53.3   5  0.020-0.030   0.020   64.0- 64.0


                     10  0.200-0.400  O.?00   0.0-  1.5  10  0.200-0.200  0.200   0.0-  1.5  10  0.200-0.300   0.200    0.0-  1.5
                      5  0.200-0.200  O.?oo  33.5- 64.0   5  0.200-0.200  0.200  53.3- 53.3   5  0.200-0.200   0.200   64.0- 64.0
                           1.7-  2.3
                                        l.B
                                                               2.1-  3.9
                                                                            3.0
                                                           1.8-  3.0
                                                                                                                 2.4
                         " N = NO. OF SAMPLES
                         «* MAXIMUM DEPTH SAMPLED AT EACH SITE
                         *»« s = MO. OF SITES SAMPLED ON THI^ DATE

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                                   8
B.    Biological  Characteristics:

     1.    Phytoplankton -
          Sampling
          Date

          04/07/75
          07/23/75
          09/11/75
Dominant
Genera

1.   Melosira
2.   Chroomonas
3.   Cryptomonas

    Other genera

         Total ,

1.   Mallomonas
2.   Oocystis
3.   Ankistrodesmus
4.   Melosira

    Other genera

         Total

1.   Coelosphaerium
2.   Melosira
3.   Aphanizomenon
4.   Ankistrodesmus
5.   Asterionella

    Other genera

         Total
Algal
Unit
per ml

 1,036
   192
   154
 1,382

   286
   239
    95
    48
   668

   579
   241
    96
    48
    48

 	97.

 1,109

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

     04/07/75                   01                     2.2
                                02                     0.9
                                03                     1.7
                                04                     0.6
                                05                     0.5

     07/23/75                   01                     6.7
                                02                     4.4
                                03                     3.0
                                04                     1.3
                                05                     3.0

     09/11/75                   01                     2.8
                                02                     2.8
                                03  .                   3.5
                                04                     1.0
                                05                     1.9

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                                  10
C.   Limiting Nutrient Study:

     1.    Autoclaved,  filtered,  and nutrient spiked -

          a.   04/07/75  Stations 01-03
                         Ortho P
               Inorganic N
          Spike (mg/1)   Cone,  (mg/1)   Cone,  (mg/1)
          Control          0.008
          0.05 P           0.058
          0.05 P + 1.0 N   0.058
          1.00 N           0.008
                 0.104
                 0.104
                 1.104
                 1.104
                         Stations 04 and 05
                         Ortho P
               Inorganic N
          Spike (mg/1)   Cone,  (mg/1)    Cone,  (mg/1)
          Control           0.008
          0.05 P           0.058
          0.05 P + 1.0 N   0.058
          1.00 N           0.008

          b.    09/11/75  Stations 01-03

                         Ortho P
                 0.072
                 0.072
                 1.072
                 1.072
               Inorganic N
          Spike (mg/1)   Cone,  (mg/1)    Cone,  (mg/1)
          Control
          0.05 P
          0.05 P + 1.0
          1.00 N
  0.005
  0.05-5
  0.055
  0.005
0.050
0.050
1.050
1.050
          Spike (mg/1)

          Control           0.005
          0.05 P           0.055
          0.05 P + 1.0 N   0.055
          1.00 N           0.005
Stations 04 and 05

Ortho P        Inorganic N
Cone, (mg/1)   Cone, (mg/1)
                 0.055
                 0.055
                 1.055
                 1.055
             Maximum Yield
             (mg/1-dry wt.)

                  0.9
                  3.9
                 18.9
                  0.6
             Maximum Yield
             (mg/1-dry wt.)

                  0.2
                  2.4
                 18.9
                  0.2
Maximum Yield
(mg/1-dry wt.)

     0.3
     4.4
    18.9
     0.3
             Maximum Yield
             (mg/1-dry wt.)

                  0.4
                  4.0
                 18.6
                  0.4

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                                  11
2.   Discussion -
          The control  yield of the assay alga,  Selenastrum capri-
     cornutum, indicate that the potential  primary productivity in
     Dworshak Reservoir was low to moderate at  the times  assay samples
     were collected (04/07/75, 09/11/75).  In all  assays, a signifi-
     cant increase in yield occurred when phosphorus was  added alone
     and in combination with nitrogen indicating phosphorus limitation.
     The addition of only nitrogen resulted in  a yield which was not
     significantly greater than that of the control.
          The mean inorganic nitrogen to orthophosphorus  ratios (N/P)
     in the lake data were less than 12/1 on all sampling occasions,
     suggesting nitrogen limitation (a mean N/P ratio of  14/1 or greater
     generally reflects phosphorus limitation).

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                                  12
IV.   NUTRIENT LOADINGS
     (See Appendix  D for data)
          For the determination  of nutrient  loadings,  the  Idaho  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 month of June when two samples were collected.   Sampling was
     begun in October 1974, and  was  completed in September 1975.
          Through an interagency agreement,  stream flow estimates for  the
     year of sampling and a "normalized" or  average  year were provided by
     the Idaho District Office of  the  U.S. Geological  Survey for the
     tributary sites nearest  the lake.
          In this report, nutrient loads for sampled tributaries were
     determined by  using a modification of the  U.S.  Geological Survey
     computer program for calculating  stream loadings.   Nutrient loads
     indicated for  tributaries 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
                             2
     nutrient loads, in kg/km /yr, in  North  Fork Clearwater  River,
     Breakfast Creek and Little  North  Fork Clearwater  River  at Stations
                                                                    2
     A-2, G-l and H-l and multiplying  the  means by the ZZ  area in km .
          Nutrient  loads for  the Headquarters and Elk  River  wastewater
     treatment plants were estimated at 1.134 kg P and 3.401 kg  N/capita/year.

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                                       13
A.   Waste Sources:

     1.   Known municipal
     Name

     Headquarters

     Elk River
Pop.*
Served

  250

  250
Treatment*

Stabilization
Pond
Stabilization
Pond
Mean Flow
(m3/d x 1Q3)

  0.095**

  0.095**
Receiving
Water

Reeds Creek

Elk Creek
     2.   Known industrial - None
    *U.S. EPA, 1971.      .
   **Estimated at 0.3785 m /capita/day.

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                                  14
B.    Annual  Total  Phosphorus Loading - Average Year:
     1.   Inputs -
                                                            % of
          Source                             kg P/yr         total
          a.   Tributaries (nonpoint load)  -
               A-2 North Fork Clearwater     61,540          53.4
                    River
               B-l Elk Creek                  6,505           5.6
               F-l Reeds Creek                5,405           4.7
               6-1 Breakfast Creek            5,735           5.0
               H-l Little North Fork         12,010          10.4
                    Clearwater River
          b.   Minor tributaries and immediate
               drainage (nonpoint load) -    22,205          19.3
          c.   Known municipal STP's -
               Headquarters                     285           0.2
               Elk River                        285           0.2
          d.   Septic tanks - None known
          e.   Known industrial - None
          f.   Direct precipitation* -        1,345           1.2
                              Totals        115,315         100.0%
     2.   Output - A-l Clearwater River      84,025
     3.   Net annual P accumulation -        31,290
    *Estimated (See NES Working Paper No.  175).

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                                  15
C.   Annual Total Nitrogen Loading - Average Year:

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

          a.   Tributaries (nonpoint load) -

               A-2 North Fork Clearwater    1,880,085        57.9
                    River
               B-l Elk Creek                   55,420         1.7
               F-l Reeds Creek                 42,320         1.3
               G-l Breakfast Creek            190,205         5.9
               H-l Little North Fork          313,375         9.6
                    Clearwater Creek

          b.   Minor tributaries and immediate
               drainage (nonpoint load) -     681,835        21.0

          c.   Known municipal STP's -

               Headquarters                       850        <0.1
               Elk River                          850        <0.1

          d.   Septic tanks - None known

          e.   Known industrial - None

          f.   Direct precipitation* -         83,010         2.6

                              Totals        3,247,950       100.0%

     2.   Outputs - A-l Clearwater River    1,892,860

     3.   Net annual N accumulation -       1,355,090
    *Estimated (See NES Working Paper No. 175).

-------
                                  16
D.    Mean Annual  Nonpoint Nutrient Export by Subdrainage Area:
                                               2              2
     Tributary                          kg P/km /yr    kg N/km /yr

     North Fork Clearwater River            17             534
     Elk Creek                              27             230
     Reeds Creek                            33             262
     Breakfast Creek                        17             569
     Little North Fork Clearwater River     18             462

E.    Mean Nutrient Concentrations in Ungaged Streams:

                                        Mean Total  P   Mean Total  r
     Tributary                             (mg/1)         (mg/1)

     C-l Cranberry Creek                 0.031           0.643
     D-l Swamp Creek                     0.029           0.532
     E-l Weitas Creek                    0.033           0.393
     J-l Isabella Creek                  0.013           0.516

-------
                                  17
F.    Yearly Loadings:
          In the following table, the existing phosphorus 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 be applicable to water
     bodies with very short retention times or in which light penetration
     is severely restricted from high concentrations of suspended solids
     in the surface waters.
                             Total Yearly
                          Phosphorus Loading
                               (g/m2/yr)
     Estimated loading for Dworshak Reservoir                    1.50
     .Vollenweider's "eutrophic" loading                          1.56
     Vollenweider's "oligotrophic" loading                       0.78

-------
                                  18
V.   LITERATURE REVIEWED

     Falter, C. Michael, Rudy R.  Ringe, Jack Skille,  and Rick Stowell.
       1974.  Limnology in Dworshak Reservoir in the  Second Year after
       Dam Closure.   Interim report submitted to U.S.  Army Corps of
       Engineers, Walla Walla District.

     Idaho Department of Water Resources,  Department  of Health and
       Welfare, Department of Fish and Game, and Department of Budget,
       Policy Planning and Coordination.   1975.   Idaho Environmental
       Overview.  Boise, Idaho.

     Murrey, A.E.  1977.  Personal communication (nutrient contri-
       butions to Dworshak Reservoir).  Idaho Department of Health and
       Welfare.  Boise, Idaho.

     Ray, Herman.  1976.  Personal communication (morphometric data of
       selected Idaho water bodies).   Boise, Idaho.

     U.S. Army Corps of Engineers.  1974.   Draft Environmental Impact
       Statement on  Dworshak Dam  and Reservoir.   Walla Walla, Washington,

     U.S. Environmental Protection Agency.   1971.   Inventory of Waste-
       water Treatment Facilities.  EPA Publication No.  OWP-1.  Office
       of Media Programs, Office  of Water  Programs, Washington, D.C.

     U.S. Environmental Protection Agency.   1975.   National  Eutrophi-
       cation 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.

-------
                                19





VI.  APPENDICES
                         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 meters/sec x 35.315 = cubic feet/sec
Centimeters x 0.3937 = inches
Kilograms x 2.205 = pounds
Kilograms/square kilometer x 5.711  ~ Ibs/square mile

-------
    APPENDIX B



TRIBUTARY FLOW DATA

-------
                                    TRIBUTARY FLOW  INFORMATION FOR IDAHO

L»KE CODE 160*      DWORSHAK  RESERVOIR

     TOTAL DRAINAGE  AREA  OF  LAKF(SO KM)   6319.6
                                                                                 OR/23/76
                                                                  NORMALIZED FLOWS(CMS)
TRIBUTARY  ARF.AISQ  KM)
1604A1
1604A?
1604B1
1604F1
1604G1
1604H1
1604Z7
6319.6
35??.4
 ?40.4
 161.6
 334.1
 678.6
1383.1
JAN
85.80
62.58
4.28
2.86
6.09
10.02
23.56
FE8
96,26
79.00
5.38
3.62
7.08
13.22
29.73
MAP
14?.00
96.56
*.60
4.42
12.49
?n.33
41.34
APR
353.39
150.93
10.31
6.91
17.47
29.17
62.30
MAY
516.22
362.46
24.7?
16.62
39.64
64.95
152.91
JLIN
324.79
270.43
18.46
12.40
24.04
65.70
110.44
JUL AUG SF.P
100.24 44.17 38.51
76.74 30.58 30.30
5.24 2.10 2.07
3.51 1.39 1.39
7.B7 3.06 2.69
19.03 6.63 5.41
32.28 12.40 11.58
OCT
52.67
36.25
2.46
1.67
3.00
5.83
13.42

fn
*3
.7
7.
3
7
1*.
NOV
.25
.89
.00
.01
.85
.42
.54
DEC
100.81
42.7*
2.92
1.95
4.45
7.82
16.93
MEAN
161.71
106.92
7.30
4.90
11.00
23.00
43.66
SUMMARY
TOTAL
SUM OF
DRAINAGE
AREA OF
LAKF. =
SUB-DRAINAGE AREAS =
6319
6320
.6
.1
TOTAL FLOW IN =
TOTAL FLOW OUT =
2359
1939
.44
.14






     MEAN MONTHLY  FLOWS  AND DAILY FLOWS(CMS)
TRIBUTARY   MONTH    YEAR
1604A1
                 MEAN FLOW
FLOW  DAY
FLOW  DAY
FLOW
1604A2
10
11
1?
1
•?_
3
4
5
6
7
8
9
10
11
12
1
2
•\
4
5
6
7
8
9
74
74
74
75
75
75
75
75
75
75
75
75
74
74
74
75
75
75
75
75
75
75
75
75
74.190
155.743
100.242
140.735
367.836
312.618
108.170
156.875
230.499
137.054
96.730
211.810
?2.172
25.882
22.370
36.161
26.929
45.024
76.739
?99.875
406.063
139.715
48.507
31.885
19
17
26
27
19
?1
15

15
14
17
1"
2n
17
23
?7
19

12

24
19
17
13
63.430
207.279
60.032
239.277
431.265
287.133
155.743

76.455
107.604
146.681
252.020
21.294
22.653
24.013
34.263
27.184

60.881

334.139
90.331
37.945
30.582
                                                            ?9
                                                                    586.159

-------
LAKE CODE 1604
                TRIBUTARY FLOW  INFORMATION  FOR  IDAHO
DWORSHAK RESERVOIR
                                                                                           08/23/76
     MEAN MONTHLY FLO*S AND DAILV FLO»-S(CMSI
TRIBUTARY   MONTH   YEAR    MEftN FLOW  DAY
160491
1604F1
1604G1
1604H1
                                FLOW   DAY
FLOW  DAY
FLOW
10
11
12
1
?
3
4
5
f
7
8
9
in
11
12
1
2
3
4
5
6
7
8
9
in
11
12
1
2
3
4
5
6
7
8
9
10
1 1
12
1
?
3
4
5
6
7
a
9
74
74
74
75
75
75
75
75
75
75
75
75
74
74
74
75
75
75
75
75
75
75
75
75
74
74
74
75
75
75
75
75
75
75
75
75
74
74
74
75
75
75
75
75
75
75
75
75
1.501
1.756
1.529
2.464
1.841
3.058
5.?39
20.445
27.694
9.543
3.313
2.180
6.4?8
7.504
6.485
10.477
7.815
13.026
2?. 229
86.933
117.515
40.493
14.045
9.231
2.322
2.690
2.322
3.794
2.803
4.729
8.099
31.998
43.608
14.810
5.097
3.341
5.040
5.918
5.069
8.353
6.145
10.506'
18.293
75.606
103.640
34.263
11.327
7.334
19
17
26
27
19
2n
1?

16
19
If.
13
19
16
2*
27
19
20
1?

15
19
16
13
19
16
26
?7
19
2n
12

15
19
16
1?
19
16
26
27
19
2n
12

15
19
16
13
1.444
1.557
1.501
2.350
1.869
3.228
4.163

28.883
6.173
2.520
2.095
6.145
7.164
6.371
9.939
7.872
13.705
17.641

127.992
26.165
10.760
8.863
2.209
2.577
2.294
3.596
3. 832
4.955
6.400

47.289
9.543
3.879
3.200
4.814
S.635
4.984
7.900
6.230
11.044
14.385

112.984
21 .691
H. 580
7.023
                                                                    17.811
                                                           28
                                                                    75.606
                                                           28
                                                                    27.835
                                                           28
                                                                    65.412

-------
        APPENDIX C



PHYSICAL AND CHEMICAL DATA

-------
STORET RETRIEVAL  DATE 76/08/25
MATL EUTRPPHICATION SURVEY
EPA-LAS VEGAS

DATE
FROM
TO
75/04/07







75/07/23







75/09/11










TIME DEPTw
OF
DAY
12
12
12
12
12
12
12
12
16
16
16
16
16
16
16
16
14
14
14
14
14
14
14
14


FEF.T
00
00
00
00
00
00
00
00
40
40
40
40
40
40
40
40
10
10
10
10
10
10
10
10
0000
0005
0015
0025
0050
0100
0150
0210
0000
0005
0020
0030
0060
0100
0140
0175
0000
0005
0025
0034
0060
0110
0160
0210
00010
WATER
TEMP
CENT








24.
22,
13.
11.
7.
6.
5.
5.
16.
16.
16.
10.
5.
4.
3.
2.
 160401
46 31 06.0  116 17 25.0 3
OfcORSHAK RESERVOIR
16035   IDAHO
11EPALES
2111202
0999 FEET DEPTH CLASS
00300
DO

MS/L
11.2
11.2
11 .0
10.6
10.2
8.6
7.6
8.8
8.0
8.4
9.8
9.6
10.4
10.6
10.8
9.4
9.0
8.8
9.0
8.8
10. 0
10.4
10.8
9.8
00077 00094
TKANSP CNDUCTVY
SECCHI FIELD
INCHES MICROMHO
90 22
23
24
23
23
24
25
25
84 30
32
23
20
18
17
20
18
72 23
16
12
6
1
3
5
9
00400
PH

SU
7.10
7.00
7.00
7.10
6.80
7.00
6.90
7.00
8.65
8.40
7.70
7.50
7.30
7.20
7.30
8.45
7.00
6.95
7.00
6.65
6.55
6.40
6.50
6.60
00410
T ALK
CAC03
MG/L
22
21
22
22
22
18
18
17
16
15
14
16
15
15
17
17
24
20
23
17
22
17
22
27
00610
NH3-N
TOTAL
MG/L
0.020K
0.020K
0.020K
0.020K
0.020
0.020
0.020K
0.020
0.020
6.020
0.020
0.020K
0.040
0.020
0.020
0.0?OK
0.020K
0.020K
0.030
0.020K
0.020K
0.020K
0.020K
0.020K
00
00625
TOT KJEL
N
MG/L
0.200
0.200K
0.200K
0.200K
0.200K
0.200K
0.200
0.200K
0.200K
0.200K
0.200K
0.200K
0.200K
0.200K
0.200K
0.200K
0.200
0.300
0.300
0.200
0.200
0.200
0.200
0.200K

00630
N02*^03
N-TOTAL
MG/L
0.050
0.050
0.060
0.060
0.070
0.090
0.110
0.110
0.020
0.020K
0.020K
0.020K
0.030
0.070
0.070
0.060
0.020K
0.020K
0.020K
0.020K
0.060
0.060
0.060
0.060

00671
PHOS-DIS
ORTHO
MG/L P
0.006
0.011
0.015
0.011
0.013
0.009
0.017
0.01?
0.012K
0.013K
0.012K
0.010K
0.012K
0.012K
0.013K
0.014K
0.004
0.003
0.005
0.002
0.005
0.005
0.005
0.007
             K VALUE KNOWN TO BE LESS
                 THAN INDICATED

-------
5TORET RETRIEVAL D«TE 76/08/25
MAIL EUTROPHICATION SURVEY
EPA-LAS VEGAS
 160401
46 31 06.0 116 17 25.0
OWOPSHAK RESERVOIR
16035   IDAHO
                                                                                           130891
                                                                  11EPALES
                                                                   0999 FEET   DEPTH
                     2111202
                   CLASS 00
DATE
FROM
TO
75/04/07







75/07/23







75/09/11







00665 32217 00031
TIME DEPTH PHOS-TOT CHLRPHYL INCDT LT
OF A OEMNING
DAY FEET
12
12
12
12
12
12
12
12
16
16
16
16
16
16
16
16
14
14
14
14
14
14
14
14
00
00
00
00
00
00
00
00
40
40
40
40
40
40
40
40
10
10
10
10
10
10
10
10
0000
0005
0015
0025
0050
0100
0150
0210
0000
0005
0020
0030
0060
0100
0140
0175
0000
0005
0025
0034
0060
0110
0160
0210
MG/L P
0,
0.
0,
0,
0,
0,
0,
0,
0.
0,
0,
0,
. 0,
0.
0,
0.
0.
0.
0.
0.
0.
0.
0.
0.
,028
,018
.017
,017
.016
,018
.018
.01*
.011
.013
,009
.007
,007
,007
,007
,010
,016
,011
,010
,007
,007
,008
,010
,010
UG/L PERCENT
2.2







6.7







2.8








-------
STORE! RETRIEVAL  DATE 76/08/35
NATL FUTROPHICATION SURVEY
EPA-LAS VEGAS
                       00010
DATE
FROM
TO
75/04/07







75/07/23







75/09/11







TIME
OF
DAY
12
12
12
12
12
12
12
12
14
14
14
14
14
14
14
14
11
11
11
11
11
11
11
11


45
45
45
45
45
45
45
45
15
15
15
15
15
15
15
15
45
45
45
45
45
45
45
45
DEPTH

FEET
0000
0005
0015
0025
0050
0100
0150
0210
0000
0005
0025
0030
0060
0100
0140
0175
0000
0005
0020
0030
0060
0110
0160
0210
*ATER
TEMP
CENT
2.7
3.2
3.2
3.0
2.9
2.8
2.5
2.5
24.0
21.6
17.8
11.6
7.2
6.4
5.7
5.0
16.1
16.1
15.6
11.6
5.7
4.0
3.1
1.9
 160403
46 35 50.0  116 17 18.0 3
DWORSHAK RESERVOIR
16035    IDAHO
                                                                                               130891
11EPALES
2111202
0999 FEET DEPTH CLASS
00300
DO

MG/L
11. a
11.4
11.6
11.4
11.2
11.0
11.2
11.2
8.2
8.8
10.0
9.6
11,4
11.0
11.0
10.0
9.4
8.6
8.6
9.0
10.2
10.2
10.4
9.4
00077 00094
TRANSP CNDUCTVY
SECCHI FIELD
INCHES MICROMHO
78 24
24
24
24
24
23
24
25
114 32
30
29
21
19
19
15
16
120 19
17
10
5
1
1
2
7
00400
PH

su
7.10
7.00
7.10
7.10
6.80
7.10
7.00
7.00
7.95
8.00
7.95
7.55
7.50
7.40
7.40
7.15
6.60
6.60
6.60
6.50
6.50
6.50
6.50
6.60
00410
T ALK
CAC03
. MG/L
19
18
18
18
18
19
20
21
15
15
16
15
15
15
14
15
10K
10K
10K
10K
10K
10K
19
19
00610
NH3-N
TOTAL
MG/L
0.030
0.020K
0.020K
0.020
0.020
0.0?OK
0.0?0
0.020K
0.030
Q.030
0.020
0.020
0.0?0
0.020
0.020K
0.0?OK
0.020K
0.0?OK
0.020K
0.020K
0.020K
0.020K
0.0?OK
0.0?OK
00
00625
TOT KJEL
N
MG/L
0.400
0.200K
0.200K
0.100
0.200K
0.200K
0.200K
0.200
0.200K
0.200K
0.200K
0.200K
0.200K
0.200K
0.200K
0.200K
0.200K
0.200K
0.200K
0.200K
0.200K
0.200*
0.200
0.200

00630
N02&.N03
N-TOTAL
MG/L
0.080
0.070
0.070
0.070
0.070
0.070
0.070
0.070
0.020
0.020K
0.020K
0.020K
0.040
0.070
o.oao
0.070
0.020K
0.020K
0.020K
0.020K
0.020K
0.070
0.080
0.040

00671
PHOS-OIS
ORTHO
MG/L P
0.013
0.013
o.ooe
0.011
0.015K
0.012
0.015
0.006
0.017K
0.013K
0.012K
0.011K
0.015K
0.013K
0.013K
0.013K
0.004
0.003
0.003
0.002
0.004
0.005
0.011
0.006
               K VALUE KNOWN TO BE LESS
                   THAN  INDICATED

-------
STORET RETRIEVAL DATE 76/08/25
NATL EUTHOPHICATION SURVEY
EPA-LAS VF6AS
 160402
46 35 50.0 116 17 18.0
DWORSHAK RESERVOIR
16035   IDAHO
                                                                                           130891
                                                                  11EPALES
                                                                   0999 FEET
                     2111202
            DEPTH  CLASS  00
DATE
FROM
TO
75/04/07







75/07/23







75/09/11







00665 32217 00031
TIME DEPTH PHOS-TOT CHLRPHYL INCDT LT
. OF A RF.MNING
DAY FEET
12
12
12
12
12
12
12
12
14
14
14
14
14
14
14
14
11
11
11
11
11
11
11
11
45
45
45
45
45
45
45
45
15
15
15
15
15
15
15
15
45
45
45
45
45
45
45
45
0000
0005
0015
0025
0050
0100
0150
0210
0000
0005
0025
0030
0060
0100
0140
0175
0000
0005
0020
0030
0060
0110
0160
0210
MG/L
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
p
017
013
016
013
012
013
015
015
012
010
014
007
006
006
007
010
014
010
012
008
007
009
013
010
UG/L PERCENT
0.9







4.4







2.8








-------
STO&ET RETRIEVAL  DATE 76/08/35
NATL EUTROPHICATION SURVEY
EPA-LAS VEGAS
  DATE
  FRO"
   TO

75/04/07
75/07/23
75/09/11
0001
TIME DEPTH WATER
OF TEMP
DAY FEET
13
13
13
13
13
13
15
15
15
15
15
15
15
11
11
11
11
11
11
11
11
25
25
25
25
25
25
40
40
40
40
40
40
40
15
15
15
15
15
15
15
15
0000
0005
0015
0025
0050
oiin
0000
0005
0015
0030
0070
0120
0175
0000
0005
0020
0030
0060
0110
0160
0210
CENT
3
3
3
3
3
3
22
21
16
11
7
6
5
15
15
15
11
5
4
3
2
0

.8
.7
.7
.7
.4
.1
.4
.4
.5
.6
.1
.1
.1
.9
.6
.3
.5
.2
.1
.2
.1
 160403
46 38 10.0  116  14  03.0
DWORSHAK RESERVOIR
16035   IDAHO
                                                                                              1308
-------
STORET RETRIEVAL DATE 76/08/25
NATL EUTROPHICATION SURVEY
EPA-LAS VEGAS
 160403
46 38 10.0 116 14 03.0 3
DrfORSHAK RESERVOIR
16035   IDAHO
                                                                                           130991
                                                                 11EPALES
                                                                  0125 FEET
                                                                             DEPTH
                     2111202
                   CLASS 00
DATE
FROM
TO
75/04/07





75/07/23






75/09/11







00665 32217 00031
TIME DEPTH PHOS-TOT CHLRPHYL INCDT LT
OF A RFMNING
PAY FEET
13
13
13
13
13
13
15
15
15
15
15
15
15
11
11
11
11
11
11
11
11
25
25
25
25
25
25
40
40
40
40
40
40
40
15
15
15
15
15
15
15
15
0000
0005
0015
0025
0050
0110
0000
0005
0015
0030
0070
0120
0175
0000
0005
0020
0030
0060
0110
0160
0210
MG/L P
0.
0.
0,
0,
0,
0,
0.
0,
0
0,
0,
0,
0,
0.
0,
0,
0.
0,
0.
0,
0,
,023
.014
,014
,013
,015
.034
,009
,010
.009
,005
,006
.006
.008
.011
.010
.012
.007
,009
,009
.013
,014
UG/L PERCENT
1.7





3.0






3.5








-------
STOftET RETRIEVAL  DATE 76/08/25
NATL EUTROPHICATIOM  SURVEY
EPA-LAS VEGAS
DATE
FRO"
TO
75/04/07





75/07/23







75/09/11







00010
TIME DEPTH WATER
OF TF.MP
DAY FEET
12
12
12
12
12
12
14
14
14
14
14
14
14
14
10
10
10
10
10
10
10
10
20
20
20
20
20
20
30
30
30
30
30
30
30
30
10
10
10
10
10
10
10
10
ooon
0005
0015
0065
oiao
0170
0000
0005
0015
0030
0060
0100
0140
0175
0000
0005
0033
0050
0090
0130
0170
0210
CENT
4
4
4
4
4
4
22
21
15
11
7
6
5
5
16
16
11
7
4
3
2
2

.3
.?.
.2
.1
.1
.1
.9
.7
.7
.6
.3
.5
.8
.2
.0
.0
.0
.7
.3
.7
.9
.1
 160404
46 38 35.0  116  01  35.0 3
DtfORSHAK RESERVOIR
16035   IDAHO
                                                                                             130891
11EPALES
2111202
0999 FEET DEPTH CLASS
00300
DO

MG/L
11.0
10.6
11.0
11.0
10.6
11.0
8.6
8.4
8.2
9.4
10.6
8.2
10.8
10.8
8.2
8.4
8.2
9.2
10.4
10.6
10.2
9.6
00077 00094
TRANSP CNDUCTVY
SECCHI FIELD
INCHES MICROMHO
66 15
17
17
17
17
20
154 30
30
24
19
17
16
15
16
120 27
22
13
1
IK
1
3
6
00400
PH

SIJ
6.90
6.70
6.60
6.50
6.70
6.70
7.40
7.35
7.60
7.40
7.20
7.10
7.10
7.05
6.90
6.70
6.70
6.65
6.60
6.50
6.50
6.40
00410
T ALK
CAC03
MG/L
13
12
14
13
14
17
16
17
15
25
22
23
23
25
25
30
20
22
19
25
22
23
00610
NH3-N
TOTAL
MG/L
0.020
0.030
0.0?0
0.020
0.020
0.030
0.020
0.020K
0.020K
0.030
0.020
0.030
0.020K
0.020K
0.020K
0.020K
0.0?OK
0.020K
0.020K
0.020K
0.020K
0.020K
00
00*25
TOT KJEL
N
MG/L
0.200
0.200K
0.200K
0.200K
0.200K
0.200K
0.200K
0.200K
0.200
0.200K
0.200K
0.200K
0.200K
0.200K
0.200K
0.200K
0.?OOK
0.200K
0.200K
0.200K
0.200K
0.200K

00630
N02R.N03
N-TOTAL
MG/L
O.OBO
0.070
0.060
0.060
0.060
0.060
0.020K
0.020K
0.020K
0.020K
0.060
0.060
0.080
0.080
0.020K
0.020K
0.020K
0.030
0.060
o.nso
0.080
0.080

00671
PHOS-DIS
ORTHO
MG/L P
0.008
0.007
0.010
0.010
0.004
0.008
0.008
0.004
0.009
0.018K
0.013K
0.014K
0.013K
0.013K
0.004
0.003
0.003
0.004
0.004
0.006
0.006
0.006
                       K VALUE KNOWN TO BE LESS
                           THAN INDICATED

-------
STORET RETRIEVAL DATE 7^/08/25
NATL EUTPOPHICATION SURVEY
EPA-LAS VEGAS
 160404
46 38 35.0 116 01 35.0
DWORSHAK RESERVOIR
16035   IDAHO
                                                                                           130«91
                                                                  11EPALES              2111203
                                                                   0999  FEET   DEPTH  CLASS 00
DATE
FROM
TO
75/04/07





75/07/23







75/09/11







00665 32217 00031
TIME DEPTH PHOS-TOT CHLRPHYL INCDT LT
OF A REMNING
DAY FEET
12
12
12
12
12
12
14
14
14
14
14
14
14
14
10
10
10
10
10
10
10
10
20
20
20
20
20
20
30
30
30
30
30
30
30
30
10
10
10
10
10
10
10
10
0000
0005
0015
0065
0120
0170
ooon
0005
0015
0030
0060
0100
0140
0175
0000
0005
0033
0050
0090
0130
0170
0210
MG/L P
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
.016
.015
.014
.016
.021
.020
.014
.012
.013
.008
.007
.006
.007
.007
.009
.009
.013
.007
.008
.008
.011
.011
UG/L PERCENT
0.6





1.3







1.0








-------
STORE! RETRIEVAL DATE 76/08/25
NATL EUTROPHICATION SURVEY
EPA-LAS VEGAS

DATE
FRO"
TO
75/04/07





75/07/23







75/09/11









TIME
OF
DAY
13
13
13
13
13
13
15
15
15
15
15
15
15
15
10
10
10
10
10
10
10
10


00
00
00
00
00
00
00
00
00
00
00
00
00
00
40
40
40
40
40
40
40
40

DEPTH

FEET
0000
0005
0015
0065
0120
0170
0000
0005
0015
0030
0060
0100
014Q
0175
0000
0005
0025
0032
0060
0110
0160
0210
00010
WATER
TEMP
CENT
4.5
4.3
4.3
4.2
4.1
4.2
22.8
22.5
17.5
11.5
7.1
6.3
5.2
5.1
15.4
15.8
14.8
11.9
5.5
4.0
3.2
2.1
 160405
46 36 42.0  116 08 30.0 3
DWORSHAK  RESERVOIR
16035    IDAHO
                                                                                              130891
11EPALES
2111202
0999 FEET DEPTH CLASS
00300
DO

MG/L
11.0
11.8
11.2
11.2
11.0
11.0
8.2
7.8
9.0
9.6
10.8
11.0
10.8
10.6
9.0
8.3
8.6
8.0
10.0
10.4
10.2
10.2
00077 00094
TRANS" CNDUCTVY
SECCHI FIELD
INCHES MICROMHO
66 17
16
16
16
15
13
126 34
30
25
20
18
18
18
15
96 22
21
17
8
1
1
1
IK
00400
PH

SU
6.90
6.80
6.70
6.60
6.50
6.70
8.05
R.OO
7.40
7.20
7.10
7.20
7.20
7.20
6.60
6.65
6.60
6.60
6.60
6.60
6.70
6.60
00410
T ALK
CAC03
MG/L
17
16
18
18
22
23
26
28
26
26
25
28
28
29
15
13
14
10K
15
18
18
14
00610
NH3-N
TOTAL
MG/L
0.020
0.020
0.0?0
0.030
0.030
0.030
0.020
0.020K
0.020K
0.040
0.020K
0.020K
0.020
0.020K
0.020K
0.020K
0.020K
0.020K
0.020K
0.020K
0.020K
0.030
00
00625
TOT KJEL
N
MG/L
0.200*
0*200K
0.200K
0.200K
0.200K
0.200K
0.200*
0.200K
0.200K
0.200K
0.200K
0.200K
0.200*
0.200K
0.200K
0.200K
0.200K
0.200K
0.200K
0.200K
0.200K
0.200K

00630
N02J.N03
N-TOTAL
MG/L
0.070
0.070
0.070
0.080
0.070
0.070
0.030
0.020K
0.020K
0.030
0.040
0.080
0.090
0.090
0.020K
0.020K
0.020K
0.020K
0.040
0.080
0.080
0.070

00671
PHOS-DIS
OPTHO
MG/L P
0.011
0.006
0.005
0.005
0.004
0.007
o.o UK
0.010K
0.012K
0.013K
0.013K
0.012K
0.014K
0.013K
0.003
0.002
0.003
0.002
0.003
0.005
0.005
0.005
                    K VALUE KNOWN TO BE LESS
                        THAN INDICATED

-------
STORET RETRIEVAL DATE 76/08/25
NATL EUTROPHICATION SURVEY
EPA-LAS VEGAS
 160405
46 36 42.0 116 OR 30.0 3
DHORSHAK RESERVOIR
16035   IDAHO
                                                                                           130891
                                                                 11EPAUES             2111202
                                                                  0999 FEET  DEPTH  CLASS  00
DATE
FROM
TO
75/04/07





75/07/23







75/09/11







00665
TIME DEPTH PHOS-TOT
OF
DAY FEET
13
13
13
13
13
13
15
15
15
15
15
15
15
15
10
10
10
10
10
10
10
10
00
00
00
00
00
00
00
00
00
00
00
00
00
00
40
40
40
40
40
40
40
40
0000
0005
0015
0065
0120
0170
0000
0005
0015
0030
0060
0100
0140
0175
0000
0005
0025
0032
0060
0110
0160
0210
MG/L P
0,
0,
0.
0.
0.
0.
0.
0,
0.
0,
0,
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
,017
,016
,015
,015
,017
,018
,009
,009
.011
,005
.005
,006
.006
.007
,011
,010
,010
.009
.008
.008
.009
.011
32217 00031
CHLRPHYL INCDT LT
A REMNING
UG/L PERCENT
0.5





3.0







1.9








-------
       APPENDIX D

TRIBUTARY AND WASTEWATER
  TREATMENT PLANT DATA

-------
STORET RETRIEVAL DATE  76/08/35
NATL EUTROPHICATION SURVEY
EPA- LAS VEGAS
  DATE   TIME DEPTH N02S.N03
  FROM    OF
   TO    OAV  FEET
74/10/19
74/11/17
74/12/36
75/01/27
75/02/19
75/04/15
75/06/15
75/06/29
75/07/14
75/08/17
75/09/15
09
17
08
10
10
11
20
10
18
13
20
no
00
00
10
00
00
00
30
30
 1604A1
46 30 50.0 116  17 45.0  4
CLEARWATER RIVER
16      15 AHSAHKA
0/DWORSHAK RESERVOIR      130fl91
BELO DWORSHAK DAM 1.5 MI  NE  OF AHSAHKA
11EPALES             2111304
 0000 FEET  DEPTH  CLASS  00
0630
S.N03
OTAL
G/L
0.072
0.080
0.070
0.088
0.083
0.060
0.050
0.045
0.020
0.015
0.045
00625
TOT KJEL
N
MG/L
0.100K
0.100
0.300
0.100
0.300
0.500
0.650
0.550
0.150
0.450
0.200
00610
NH3-N
TOTAL
MG/L
0.025
0.025
0.020
0.016
0.016
0.010
0.020
0.030
0.020
0.015
0.010
00671
PHOS-DIS
ORTHO
MG/L P
0.005
0.005
0.005
0.016
0.008K
0.005
0.005K
0.010
0.010
0.005K
0.005
00665
PHOS-TOT

MG/L P
0.010
0.010K
0.010K
0.016
0.010K
0.010K
0.020
0.020
0.020
0.040
0.020
     K VALUE KNOWN TO BE LESS
         THAN  INDICATED

-------
STORE! RETRIEVAL DATE 76/08/25
NATL EUTROPHICATION SURVEY
EPA- LAS VEGAS
  DATE   TIME DEPTH N02R.N03
  FROM    OF
   TO    DAY  FEET

74/10/20 10 30
74/11/17 10 45
75/04/12 12 35
75/06/24 13 00
75/07/19 17 05
75/08/17 15 20
75/09/13 16 00
 1604A2
46 50 28.0 115 37  10.0 4
N FK CLEARWATER RIVER
16      7.5 SHEEP  MTN
T/DWORSHAK RESERVOIR      130891
PVO RD BROG .2 MI  W OF AJQUARIUS CAMPGRND
11EPALES             2111204
 0000 FEET  DEPTH  CLASS 00
0630
R.N03
OTAL
G/L
0.016
0.016
0.015
0.020
0.005
0.005
0.003
00625
TOT KJEL
N
MG/L
0.100K
0.100K
1.600
0.800
0.150
1.100
0.200
00610
NH3-N
TOTAL
MG/L
0.010
0.020
0.025
0.015
0.015
0.010

00671
PHOS-OIS
ORTHO
MG/L P
0.005K
0.005K
0.005
0.005
0.005
0.005K
0.002
(50665
PHOS-TOT

HG/L P
0.005K
0.010K
0.020
0.010
0.020
0.030
0.040
   K VALUE  KNOWN TO BE LESS
       THAN INDICATED

-------
STORET RETRIEVAL DATE 76/08/35
NATL EUTROPHICATION SURVEY
EPA- LAS VEGAS
  DATE   TIME DEPTH N02&N03
  FROM    OF
   TO    DAY  FEET

74/10/19 12 15
74/11/17 15 00
75/06/16 16 35
75/06/28 15 45
75/07/19 13 00
75/08/16 10 30
75/09/13 10 30
 1604B1
46 42 20.0 116 11 55.0 4
ELK CREEK
16      7.5 ELK CRK FALS
T/DWORSHAK RESERVOIR      130891
JEEP TRL 2 MI NH OF ELK CRK  PICNIC AREA
11EPALES              2111204
 0000 FEET  DEPTH  CLASS  00
0630
&N03
OTAL
G/L
0.018
0.008
0.005
0.005
0.010
0.005
0.010
00625
TOT KJEL
N
MG/L
0.300
0.100K
0.200
0.200
0.225
0.400
0.150
00610
NH3-N
TOTAL
MG/L
0.007
0.015
0.010
0.005
0.027
0.030
0.025
00671
PHOS-DIS
ORTHO
MG/L P
0.005
0.010
0.020
0.010
0.010
0.005K
0.020
00665
PHOS-TOT

MG/L P
0.010
0.010
0.040
0.020
0.030
0.060
0.045
         K VALUE KNOWN TO BE LESS
             THAN INDICATED

-------
ST09ET RETRIEVAL DATE 76/08/25
NATL EUTROPHICATION SURVEY
EPA- LAS VEGAS
  DATE   TIME DEPTH N02&N03
  FROM    OF
   TO    DAY  FEET

74/10/19 13 05
74/11/16 14 00
74/12/26 09 00
75/06/16 19 10
75/06/28 11 15
75/07/19 10 45
75/08/16 13 00
75/09/13 09 00
 1604C1
46 39 20.0  116  07  50.0 4
CRANBERRY CREEK
16      7.5 ELK  CRK FALS
T/DWORSHAK RESERVOIR     130891
UNPVD RD BROG 3  MI  N OF FIVE CORNERS JCT
11EPALES              2111204
 0000 FEET  DEPTH   CLASS 00
0630
«,N03
OTAL
G/L
0.016
0.024
0.096
0.005
0.010
0.010
0.005
0.010
00625
TOT KJEL
N
MG/L
0.300
0.100K
1.400
0.500
0.900
0.250
0.800
0.200
00610
NH3-N
TOTAL
MG/L
0.010
0.015
0.165
0.020
0.020
0.030
0.010
0.020
00671
PHOS-DIS
ORTHO
MG/L P
0.020
0.025
0.020
0.015
0.015
0.010
0.005K
0.015
00665
PHOS-TOT

MG/L P
0.025
0.025
0.040
0.030
0.015
0.040
0.020
0.050
          K VALUE KNOWN TO BE LESS
              THAN INDICATED

-------
STORET RETRIEVAL DATE 76/08/35
NATL EUTROPHICATION SURVEY
EPA- LAS VEGAS
  DATE   TIME DEPTH N02&.N03
  FROM    OF
   TO    DAY  FEET

74/10/19 14 00
74/11/16 12 00
74/12/86 11 00
75/06/16 20 30
75/06/28 11 50
75/07/19 11 15
75/08/16 13 30
75/09/13 09 35
 160401
46 40 00.0  116 01 40.0  4
SWAMP CREEK
16      7.5 LITL GRN  MTN
T/DWORSHAK  RESERVOIR      130891
UNPVD RD BRDG 2.5 MI  N  OF  BARTLETT POINT
11EPALES              2111304
 0000 FEET  DEPTH   CLASS  00
0630
&.N03
OTAL
6/L
0.016
0.016
0.024
0.005
0.010
0.015
0.005
0.002
00625
TOT KJEL
N
MG/L
0.600
0.100K
0.500
0.100
1.000
0.150
1.000
0.300
00610
NH3-N
TOTAL
MG/L
0.010
0.010
0.050
0.010
0.020
0.020
0.020
0.025
00671
PHOS-DIS
ORTHO
MG/L P
0.025
0.005
0.020
0.030
0.025
0.020
0.005K
0.015
00665
PHOS-TOT

MG/L P
0.025
0.005
0.030
0.050
0.030
0.020
0.040
0.030
             K VALUE KNOWN TO BE LESS
                 THAN INDICATED

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STORE! RETRIEVAL DATE 76/08/35
NATL EUTROPHICATION SURVEY
EPA- LAS VEGAS
  DATE   TIME DEPTH N02fs,N03
  FROM    OF
   TO    DAY  FEET

74/10/19 14 30
74/11/16 10 30
74/12/26 15 00
75/06/15 18 15
75/06/28 1* 30
75/07/19 12 30
75/08/16 13 00
75/09/13 10 00
 1604E1
46 44 05.0 116  01  20.0  4
XEITAS CREEK
16      7.5 LITL GRN MTN
T/DWORSHAK RESERVOIR     130«91
BNK ?O.P FT, N UNPVO PD 3.4 M E LTTL GR MT
11EPALES              2111204
 0000 FEET  DEPTH   CLASS 00
0630
&.N03
OTAL
G/L
0.016
0.024
0.024
0.005
0.010
0.010
0.005
0.002
00625
TOT KJEL
N
MG/L
0.400
0.200
0.500
0.200
0.750
0.100
0.700
0.200
00610
NH3-N
TOTAL
MG/L
0.005
0.015
0.030
0.010
0.020
0.015
0.015
0.025
00671
PHOS-DIS
ORTHO
MG/L P
0.010
0.010
0.005
0.010
0.005
0.005
0.005K
0.020
00665
PHOS-TOT

MG/L P
0.035
0.010
0.010K
0.020
0.010K
0.010K
0.020
0.080
         K VALUE KNOWN TO BE LESS
             THAN INDICATED

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STORET RETRIEVAL DATE 76/08/35
NATL EUTROPHICATION SURVEY
EPA- LAS VEGAS
 1604F1
46 37 30.0 116 56  30.0  4
REEDS CREEK
16      15 HEADQUARTERS
T/DWORSHAK RESERVOIR      130891
UNPVD RD BRDG 3.2  MI  W  OF HWY 11
11EPALES              2111204
 0000 FEET  DEPTH   CLASS  00
                                                                                                    JCT

DATE
FROM
TO
74/10/19
74/11/16
74/12/36
75/06/15
75/06/38
75/07/19
75/08/16
75/09/13

TIME DEPTH
OF
DAY FEET
13 35
13 00
11 30
31 05
30 15
18 00
16 20
17 00
00630
N02&,N03
N-TOTAL
MG/L
0.032
0.024
0.016
0.007
0.005
0.005
0.005
0.002
00625
TOT KJEL
N
MG/L
0.400
0.100K
0.800
0.125
0.450
0.150
0.250
0.050
00610
NH3-N
TOTAL
MG/L
0.010
0.010
0.025
0.017
0.015
0.020
0.005K
0.030
00671
PHOS-DIS
ORTHO
MG/L P
0.025
0.020
0.020
0.010
0.035
0.035
0.040
0.065
00665
PHOS-TOT

MG/L P
0.025
0.025
0.030
0.015
0.035
0.050
0.060
0.065
             K VALUE KNOWN TO BE LESS
                 THAN INDICATED

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STORET RETRIEVAL DATE 76/08/2o
NATL EUTROPHICATION SURVEY
EPA- LAS VEGAS
  DATE   TIME DEPTH N02J.N03
  FROM    OF
   TO    DAY  FEET

74/10/19 16 37
74/11/16 11 00
74/12/26 12 00
75/06/15 17 45
75/06/28 17 50
75/07/19 14 30
75/08/16 12 00
75/09/13 11 15
 1604G1
46 53 00.0 115 56  20.0  4
BREAKFAST CREEK
16      15 80EHLS  BUTTES
T/DWORSHAK RESERVOIR      130891
BNK FRM TRL  .7 MI  E OF  FRZEOUT TRL LKOUT
11EPALES              2111204
 0000 FEET   DEPTH  CLASS 00
0630
J.N03
OTAL
G/L
0.024
0.016
0.008
0.010
0.040
0.030
0.005
0.002
00625
TOT KJEL
N
MG/L
0.200
0.100K
0.500
0.400
1.050
0.350
0.400
0.200
00610
NH3-N
TOTAL
MG/L
0.015
0.010
0.015
0.020
0.025
0.015
0.010
0.020
00671
PHOS-DIS
ORTHO
MG/L P
0.020
0.005K
0.015
0.030
0.010
0.010
0.005K
0.010
00665
PHOS-TOT

MG/L P
0.022
0.005
0.020
0.030
0.010
0.020
0.010
0.020
             K VALUE KNOWN TO BE LESS
                 THAN INDICATED

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STORET RETRIEVAL DATE 76/08/35
NATL EUTROPHICATION SURVEY
EPA- LAS VEGAS
  DATE   TIME DEPTH N02&N03
  FROM    OF
   TO    DAY  FEET

74/10/19 15 45
74/11/16 11 00
74/13/26 14 00
75/06/15 15 30
75/06/28 19 00
75/07/19 15 20
75/08/16 14 00
75/09/13 12 10
 1604H1
46 54 15.0 115 50 55.0 4
LTTL N FK CLRWATEW RIV
16      15 80EHLS BUTTES
T/DWORSHAK RESERVOIR      130891
TRAIL BRDG .5 MI NW OF FINNS  CABIN
11EPALES             2111204
 0000 FEET  DEPTH  CLASS  00
0630
&N03
OTAL
IG/L
0.048
0.056
0.040
0.005
0.005
0.005
0.005
0.002
00625
TOT KJEL
N
MG/L
0.300
0.100K
1.000
0.650
0.150
0.150
0.450
0.400
00610
NH3-N
TOTAL
MG/L
0.030
0.020
0.035
0.015
0.005
0.015
0.005
0.002
00671
PHOS-OIS
ORTHO
MG/L P
0.005K
0.005K
0.005K
0.015
0.005
0.005K
0.020
0.005
00665
PHOS-TOT

MG/L P
0.005
0.010K
0.010
0.050
0.010K
0.010
0.020
0.030
           K VALUE KNOWN TO BE LESS
               THAN INDICATED

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STORE! RETRIEVAL DATE 76/08/25
NATL EUTROPHICATION SURVEY
EPA- LAS VEGAS
  DATE   TIME DEPTH N02&N03
  FROM    OF
   TO    DAY  FEET

74/10/20 10 15
74/11/17 11 00
75/04/12 14 00
75/06/15 11 30
75/06/29 13 05
75/07/19 17 00
75/08/16 12 30
75/09/13 16 10
 1604J1
46 51 00.0 115 37  47.0  4
ISABELLA CREEK
16      7.5 THOMPSON  PT
T/OWORSHAK RESERVOIR      130R91
TRAIL BROG OFF PVO RD AT  ISABELLA LNDING
11EPALES              2111204
 0000 FEET  DEPTH  CLASS  00
0630
&N03
OTAL
!G/L
0.040
0.040
0.065
0.040
0.030
0.015
0.025
0.045
00625
TOT KJEL
N
MG/L
0.100K
0.400
1.100
0.650
0.500
0.100
0.550
0.050
00610
NH3-N
TOTAL
MG/L
0.010
0.035
0.025
0.035
0.030
0.015
0.010
0.002
00671
PHOS-DIS
ORTHO
MG/L P
0.005K
0.005K
0.010
0.005K
0.005
0.005K
0.005K
0.002
00665
PHOS-TOT

MG/L P
0.005K
0.010K
0.010
0.010
0.020
0.010K
0.010K
0.010
             K VALUE KNOWN TO BE LESS
                 THAN INDICATED

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                            APPENDIX E

                   PARAMETRIC RANKINGS OF LAKES
                      SAMPLED BY NES IN 1975

                          STATE OF IDAHO
     Mean or median values for six of the key parameters  evaluated
in establishing the trophic conditions of Idaho 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 a_ 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.

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LAKE DATA TO BE USED IN RANKINGS

LAKE
CODE  LAKE NAME

1601  AMERICAN FALLS RESERVOIR

1602  CASCADE LAKE

1603  LAKE COEUR D'ALENE

1604  OWORSHAK RESERVOIR

1605  HAUSER

1606  hAYDEN LAKE

1607  ISLAND PARK RESERVOIR

1608  LAKE LOWELL

1609  MAGIC RESERVOIR

1610  PALISADES RESERVOIR

1611  LOWER PAYETTE

1612  LOWER TWIN LAKES

1613  UPPER TWIN LAKES
MEDIAN
TOTAL P
0.105
0.032
0.017
0.010
0.028
0.010
0.034
0.070
0.062
0.024
0.013
0.016
0.017
MEDIAN
INOR6 N
0.030
0.060
0.040
0.080
0.075
0.040
0.050
0.070
0.130
0.080
0.060
0.050
0.045
500-
MEAN SEC
463.800
415.067
380.348
401.866
366.286
243.500
391.778
477.111
400.750
345.428
234.000
370.000
369.143
MEAN
CHLORA
15.379
8.081
10.391
2.420
11.112
2.787
9.322
25.389
7.322
2.067
4.600
2.318
4.986
15-
MIN DO
14.700
14.800
12.200
7.400
14.800 *
11.800
12.800
14.600
14.700
12.800
9.600
13.600
8.200
MEDU
OISS ORTH
0.035
0.009
0.005
0.009
0.013
0.003
0.012
0.015
0.020
0.007
0.007
0.009
0.004

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PERCENT OF LAKES WITH HIGHER VALUES  (NUMBER OF LAKES  WITH  HIGHER  VALUES)

LAKE                                   MEDIAN     MEDIAN       500-           MEAN        15-         MEDIAN
CODE  LAKE NAME                        TOTAL P    INORG N     MEAN SEC      CHLORA      MIN DO    DISS ORTHO P

1601  AMERICAN FALLS RESERVOIR          0(0)     17 (  1)     8(1)      8(1)     21. (  2)     0 (  0)

1602  CASCADE LAKE                     33  (  4)     54 (6)     17 (   2)     42 (   5)      4(0)    50 (  5)

1603  LAKE COEUR D'ALENE               67  (  8)     96 ( 11)     50 (6)     25 (   3)     67 (8)    83 (  10)

1604  DWORSHAK RESERVOIR               96  ( ID     17 (1)     25 (   3)     83 (  10)    100 ( 12)    50 (  5)

1605  HAUSER                           42  (  5)     33 (  4)     75 (   9)     17 (   2)      4(0)    25 (  3)

160*  NAYDEN LAKE                      96  ( in     96 < ii>     92 (  11)     75 (   9)     75 (  9)   100 (  12)

1607  ISLAND PARK RESERVOIR            25  (  3)     71 (  8)     42 (5)     33 (   4)     54 (6)    33 (  4)

1608  LAKE LOWELL                       8(1)     42 (  5)     0(0)      0(0)     33 (  4)    17 (  2)

1609  MAGIC RESERVOIR                  17  (  2)     0<0)     33 (   4)     50 (   6)     21 (  2)     8 (  1)

1610  PALISADES RESERVOIR              50  (6)     17 (  1)     83 (  10)    100 (12)     54 (  6)    75 (  9)

1611  LOWER PAYETTE                    63  ( 10)     54 (  6)    100 (  12)     67 (8)     83 ( 10)    67 (  8)

1612  LONER TWIN LAKES                 75  (  9)     71 (  8) .    58 (   7)     92 (  11)     42 (5)    SO <  5)

1613  UPPER TWIN LAKES                 58  (7)     83 ( 10)     67 (8)     58 (   7)     92 ( 11)    92 (  11)

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