U.S. ENVIRONMENTAL PROTECTION AGENCY
               NATIONAL EUTROPHICATION SURVEY
                        WORKING PAPER SERIES
                                              REPORT
                                               ON
                                         ISLAND PARK ESERVOIR
                                           FREMONT COUNTY
                                               IDAHO
                                           EPA REGION X   .
                                         WORKING PAPER No, 782
     CORVALLIS ENVIRONMENTAL RESEARCH LABORATORY - CORVALLIS, OREGON
                                 and
    ENVIRONMENTAL MONITORING & SUPPORT LABORATORY - LAS VEGAS, NEVADA
•frG.P.O. 699-440

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                                 REPORT
                                   ON
                          ISLAND PARK RESERVOIR
                             FREW COUNTY
                                  IDAHO
                              EPA REGION X
                          WORKING PAPER No, 782
     WITH THE COOPERATION OF THE
IDAHO DEPARTMENT OF HEALTH AND WELFARE
                AND THE
         IDAHO NATIONAL GUARD
              JULY, 1977

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       REPORT ON ISLAND PARK RESERVOIR

            FREMONT 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.  783
     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                                17
 VI. Appendices                                         18

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                                  ii


                               FOREWORD
     The National Eutrophicatlon Survey was Initiated 1n  1972  1n
response to an Administration commitment to Investigate the  nation-
wide threat of accelerated eutrophlcation 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 nonpolnt 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 eutrophlcation 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
L§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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                                  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
Elaine, Camas
Bonneville (Lincoln in WY)
Valley
Kootenai
Kootenai

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ISLAND  PARK RESERVOIR
       Tributary Sampling Site!   >^L-/
    X  Lake Sampling Site;
       Drainage Area Boundary
                                             ISLAND PARK
                                              RESERVOIR

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                REPORT.ON  ISLAND  PARK RESERVOIR,  IDAHO
                            STORE! NO.  1607

I.    CONCLUSIONS
     A.    Trophic Condition:*
               On the basis  of Survey data and field observations,  Island
          Park Reservoir is  considered eutrophic,  i.e.,  nutrient rich
          and highly eutrophic.   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 each lake.
               Chlorophyll a^ levels in the lake ranged  from 0.9 yg/1 to
          26.3 ug/1 with a mean of 9.3 yg/1.   Potential  for primary pro-
          ductivity as measured by algal assay control  yield was high.
          The relatively high Secchi disc visibility of July sampling was
          severely depressed during September.  Of the  13 Idaho lakes
          sampled in 1975, 3 had higher median total phosphorus levels,
          8 had greater median inorganic nitrogen values and 4 had  greater
          median orthophosphorus levels than  Island Park Reservoir.
               Survey limnologists reported  heavy algal  blooms throughout
          the lake during both September and  October visits to the  lake.

     *See Appendix E.

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B.   Rate-Limiting Nutrient:
          The algal assay results indicate that Island Park Reservoir
     was limited by available phosphorus during September sampling,  and
     by available nitrogen during July and October.   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 not found
          to have contributed any of the nutrient loading to Island Park
          Reservoir.  Septic  tanks were estimated to have contributed
          0.3% of the total phosphorus load to the lake.
               The calculated annual phosphorus loading to Island  Park
                                 p
          Reservoir of 0.32 g P/m /yr was less than  Vollenweider's (1975)
          proposed oligotrophic loading for lakes with such volume and
          hydraulic retention time.  However,  this loading rate is
          probably far too low since loading calculations based upon
          nutrient concentrations indicate a net export of phosphorus
          and nitrogen from the lake, suggesting that sampling was not
          adequate to depict  actual loading and export rates.   This  ap-
          parent export could be due to an underestimation of  nutrient
          loadings from the ungaged tributaries to the reservoir,  to
          unknown industrial  or municipal point sources, or to sampling

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     error.   Additional  sampling to determine the true nutrient
     budget for the lake is needed before any recommendation on
     nutrient controllability in Island Park Reservoir can be made.
2.    Nonpoint sources -
          All of the total  phosphorus input to Island Park Reservoir
     was found to be contributed by nonpoint sources during the
     sampling year.  Ungaged tributaries were estimated to have
     contributed 13.2%,  Henrys Fork contributed 61.3% and Sheridan
     Creek contributed 7.2%.  The remaining three gaged tributaries
     collectively contributed a total of 12.5%.

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I-I.   LAKE AND DRAINAGE CHARACTERISTICS
          Lake and drainage basin characteristics  are itemized below.   Lake
     morphometry data were provided by Martin and  Hanson (1966).   Tribu-
     tary 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:  31.54 km .
          2.    Mean depth:  5.0 meters.
          3.    Maximum depth:   21.9 meters.
          4.    Volume:  156.980 x 106 m3.
          5.    Mean hydraulic retention time:   109 days.

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

     1.   Tributaries -

                                        Drainage       Mean flow
          Name                          area (km?)      (m3/sec)

          A-2 Henrys Fork                676.0           9.14
          B-l Hotel Creek                 38.3           0.52
          C-l Sheep Creek                 32.4           0.08
          D-l Icehouse Creek              19.7           0.56
          E-l Sheridan Creek             282.3           0.85

          Minor tributaries and
          immediate drainage -           165.6           2.41

                    Totals              1,214.3          13.56

     2.   Outlet - A-l Henrys Fork     1,245.8          16.61

C.    Precipitation:

     1.   Year of sampling:  34.2 cm.
     2.   Mean annual:  30.3 cm.

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III.  LAKE WATER QUALITY SUMMARY
          Island Park Reservoir was sampled three times  during  the
     open-water season of 1975 by means of a pontoon-equipped Huey  heli-
     copter.   Each time, samples for physical  and chemical  parameters
     were collected from three 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 phytoplankton  identification and  enumera-
     tion.  During the first and last visits,  18.9-liter depth-integrated
     samples  were composited for algal  assays.   Maximum  depths  sampled
     were 3.0 meters at Station 01, 14.9 meters at Station  02,  and  21.0
     meters at Station 03.   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  chloro-
     phyll ^determinations are included in III-B.  Results of  the  limiting
     nutrient study are presented in III-C.

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ISLAND PA2K  WESERvOIR
STO°ET CODE  1607
PARAMFTEP
TEMPE3ATUPE  (OEG CFNT)
O.-l.5 M  DEPTH
MAX DEPTH**

OISSOl tfED OXYGEN (MG/L)
O.-l.5 M  HEPTH
MAX DEPTH**
CONDUCTIVITY (L
O.-l.5  M DEPTH
MAX  DEPTH**

PH  (STANDARD UNITS)
O.-l.5  M OEPTH
MAX  DEPTH**

TOTAL  ALKALINITY  (MR/L)
O.-l.5  M DEPTH
MAX  DEPTH**

TOTAL  P (MG/L)
O.-l.5  M DEPTH
MAX  DEPTH**

DISSOLVED ORTHO P  (MG/L)
O.-l.5  M DEPTH
MAX  DEPTH**

N02+N03 (MG/L)
 O.-l.5 M OEPTH
 MAX  DEPTH**

 AMMONIA (MG/L)
 O.-l.S M DEPTH
 MAX DEPTH**

 KjELDAHL N  (MG/L)
 n.-l.S M DEPTH
 MAX DEPTH**
 SECCHI DISC
PHYSICAL AND CHEMICAL CHARACTERISTICS
( 7/HO/75 )
s*«» = t
N* RANGE MEDIAN
6
3
)
6
3
6
3
6
3
.)
6
3
6
3
'D
6
3
ft
3
6
3
6
3
16.8- 17.8
6.3- 16.9
6.8- 9.2
2.2- 7.fl
132.- 145.
93.- 137.
9.2- 9.4
B.I- 9.3
70.- 82.
60.- 80.
0. 018-0. 02R
0.034-0.258
0.011-0.014
0.014-0.134
0.020-0.020
0.020-0.040
0.0?0-0.030
0.030-0.400
0.200-0.400
0.200-0.500
17.6
8.5
8.7
3.2
135.
105.
9.3
8.4
74.
*?.
0.0?0
0.105
0.012
0.066
0.0?0
0.0*0
0.0?B
0. 160
O.?00
0.300
MAX
DEPTH
RANGE
(METERS)
0.0- 1.5
3.0- 21.0
0.0- 1.5
3.0- 21.0
0.0- 1.5
3.0- 21.0
0.0- 1.5
3.0- 21.0
0.0- 1.5
3.0- 21.0
0.0- 1.5
3.0- 21 .0
0.0- 1.5
3.0- 21.0
0.0- 1.5
3.0- 21.0
0.0- 1.5
3.0- 21.0
0.0- 1.5
3.0- 21.0
( 9/ 3/75 )
S»»» = 3
K.* RANGE MEDIAN
5 15.0- 16.6
2 13.6- 15.0
5 5.0- 9.2
2 5.0- 5.4

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B.   Biological Characteristics:

     1.   Phytoplankton -
          Sampling
          Date

          07/30/75
          09/03/75
          10/20/75
Dominant
Genera

1.   Aphanizomenon
2.   Chroqmonas
3.   Cryptomonas
4.   Cyanophytan
5.   Microcystis

    Other genera

         Total

1.   Aphanizomenon
2.   Chroomonas
3.   Melosira

    Other genera

         Total

1.   Fragilaria
2.   Aphanizomenon
3.   Melosira
4.   Chrysophytan
5.   Cryptomonas

    Other genera

         Total
Algal
Units
per ml

  454
  165
   83
   83
   83

   82

  950

3,254
   38
   38
3,330

  596
  553
  213
  170
   85
                                                            1,617

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2.   Chlorophyll  a_ -

     Sampling                 Station             Chlorophyll  a
     Date                     Number              (yg/D	
     07/30/75                   01                     2.8
                                02                     2.3
                                03                     5.1
     09/03/75                   OT                    £3
                                03                    26.3
     ,0/20/75                   01                    £9
                                03                     2-9

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                                  10
C.   Limiting Nutrient Study:

     1.   Autoclaved, filtered, and nutrient spiked

          a.   07/30/75
                         Ortho P
          Spike (mg/1)   Cone, (mg/1)

          Control           0.025
          0.05 P           0.075
          0.05 P + 1.0 N   0.075
          1.00 N           0.025

          b.    09/03/75
          Spike (mg/1)
          Ortho P
          Cone, (mg/1)
Control
0.05 P
0.05 P + 1.0 N
1.00 N
0.025
0.075
0.075
0.025
          c.
10/20/75
          Spike (mg/1)

          Control
          0.05 P
          0.05 P + 1.0  N
          1.00 N
          Ortho P
          Cone, (mg/1)

            0.015
            0.065
            0.065
            0.015
                         Inorganic N
                         Cone,  (mg/1)

                           0.025
                           0.025
                           1.025
                           1.025
Inorganic N
Cone, (mg/1)

  0.310
  0.310
  1.310
  1.310
Inorganic N
Cone, (mg/1)

  0.115
  0.115
  1.115
  1.115
               Maximum Yield
               (mg/1-dry wt.)

                    3.6
                    3.6
                   13.5
                    9.9
Maximum Yield
(mg/1-dry wt.)

     6.6
    17.9
    32.0
     5.4
Maximum Yield
(mg/1-dry wt.)

     6.0
     7.4
    28.4
     9.3

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                                 11
2.    Discussion -
          The control  yields of the assay alga,  Selenastrum  capri-
     cornutum, indicate that the potential  primary  productivity  in  Island
     Park Reservoir was high during all  three  sampling  periods.   In  the
     July and October  assays, a significant increase  in yield  occurred
     when nitrogen was added alone and in combination with phosphorus
     indicating nitrogen limitation at those times.   In the  September
     assay,  the addition of orthophosphorus alone produced a significant
     increase in yield over that of the  control, indicating  phosphorus
     limitation at that time.  Note that in the  September assay  the
     addition of nitrogen alone did not  result in any increase in yield
     over that of the  control.
          The mean inorganic nitrogen  to orthophosphorus ratios  (N/P)
     in the  lake data  were less than 6/1 on all  sampling occasions,
     suggesting primary limitation by  nitrogen on all three  sampling
     occasions.

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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 months of May and June when two  samples  were collected at
     some stations.   Sampling was  begun in October 1974, and was com-
     pleted in September 1975.
          Through an interagency agreement,  stream flow estimates for
     the year of sampling and a  "normalized" or average year v/ere pro-
     vided by the Idaho 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 immedi-
     ate drainage" ("ZZ" of USGS)  were estimated by  using  the mean
                                    ?
     annual nutrient loads, in  kg/km/year,  in  Hotel Creek,  Sheep Creek
     and Sheridan Creek, at Stations B-l,  C-l  and E-l  and  multiplying
                                   2
     the means by the ZZ area in km .

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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) -
               A-2 Henrys Fork                6,135          61.3
               B-l Hotel Creek                  690           6.9
               C-l Sheep Creek                  130           1.3
               D-l Icehouse Creek               430           4.3
               E-l Sheridan Creek               715           7.2
          b.   Minor tributaries and immediate
               drainage  (nonpoint load) -     1,325          13.2
          c.   Known municipal STP's - None
          d.   Septic tanks* -                   30           0.3
          e.   Known industrial - None
          f.   Direct precipitation** -         550           5.5
                              Totals         10,005         100.0%
     2.   Outputs - A-l  Henrys Fork          22,550
     3.   Net annual P export*** -           12,545
    *Estimate based on 100 lakeshore residences.
   **Estimated (See NES Working Paper No. 175).
  ***Export probably due to unknown sources and/or sampling error.

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                                  14
C.   Annual Total Nitrogen Loading - Average Year:

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

          a.   Tributaries (nonpoint load) -

               A-2 Henrys Fork               52,870          36.8
               B-l Hotel Creek                8,920           6.2
               C-l Sheep Creek                1,970           1.4
               D-l Icehouse Creek             8,325           5.8
               E-l Sheridan Creek            17,055          11.9

          b.   Minor tributaries and immediate
               drainage (nonpoint load) -    19,540          13.6

          c.   Known municipal STP's - None

          d.   Septic tanks* -                1,065           0.7

          e.   Known industrial - None

          f.   Direct precipitation** -      34,050          23.6

                              Totals        143,795         100.0%

     2.   Outputs - A-l Henrys Fork         459,510

     3.   Net annual N export*** -          315,715
    *Estimate based on 100 lakeshore residences.
   **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

     Henrys Fork                              9             78
     Hotel Creek                             18            233
     Sheep Creek                              4             61
     Icehouse Creek                          22            423
     Sheridan Creek                           2             60

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                                  16
E.   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."
          It should be noted that Vollenweider's model may not be appli-
     cable 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 Island Park Reservoir                 0.32
     Vollenweider's "eutrophic" loading                          0.78
     Vollenweider's "oligotrophic" loading                       0.39

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                                  17
V.   LITERATURE REVIEWED

     Martin, R.O.R.  and Ronald L.  Hanson.   1966.   Reservoirs in the U.S.
       Geological Survey Water Supply Paper No.  1838.   U.S.  Government
       Printing Office, Washington, D.C.

     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.

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                                18
VI.  APPENDICES
                         APPENDIX A



                     CONVERSION FACTORS

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                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 35.31G = cubic feet/sec



Centimeters x 0.3937 = inches



Kilograms x 2.205 - pounds



Kilograms/square kilometer x 5.711 ~ Ibs/squarc mile

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    APPENDIX B



TRIBUTARY FLOW DATA

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                                   TRIBUTARY  FLO*  INFORMATION FOR IDAHO
                                                                               08/23/T6
LAKE CODE 1607
       ISLAND PARK PES.
     TOTAL DRAINAGE AREA OF LAKEISO KM)
          SUB-DRAINAGE
TRIBUTARY  AREAISQ KM)
                          JAN
                      FEB
                              1245.8
                              MAR'
                                       APR
                              MAY
                                    NORMALIZED  FLOWS(CMS)
                                      JUN     JUL      AUG
                                        SEP
                             OCT
                                                                               NOV
                           DEC
                                                                                                               MEAN
1607A1
1607A2
160781
1607C1
1607D1
1607E1
1607Z7
1245.8
676.0
38.3
32.4
19.7
282.3
197.1
4.96
7.02
0.20
0.028
0.48
0.40
1.67
6.91
7.02
0.20
0.028
0.48
0.40
1.67
fl.38
7.14
0.20
0.028
0.54
0.40
1.78
12.86
10.73
0.40
0.057
0.76
1.76
2.89
27.33
14.10
1.59
0.085
0.79
3.28
4.56
25.94
9.51
1.84
0.255
0.71
1.67
4.42
30.58
11.64
0.54
0.227
0.59
0.68
2.80
31.15
11.84
0.31
0.085
0.45
0.37
2.07
22.00
8.35
0.28
0.085
0.45
0.23
1.81
13.65
7.67
0.25
0.057
0.48
0.28
1.78
R.52
7.31
0.25
0.057
0.48
0.3*
1.76
6.14
7.08
0.23
0.028
0.48
0.40
1.70
16.61
9.14
0.52
0.085
0.56
0.85
2.41
                                                                    SUMMARY
                        TOTAL DRAINAGE AREA  OF  LAKE  =
                        SUM OF SUB-DRAINAGE  AREAS    =
                                              1245.8
                                              1245.8
                                                   TOTAL  FLOW IN
                                                   TOTAL  FLOW OUT
                                                162.54
                                                198.42
     MEAN MONTHLY FLOWS AND DAILY FLOWS(CMS)
TRIBUTARY
1607A1
MONTH
        YEAR
MEAN FLOW  DAY
FLOW  DAY
FLOW  DAY
FLOW
1607A2
10
11
12
1
2
3
4
5
6
7
8
9
10
11
12
1
2
3
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
21.181
16.395
17.641
17.443
10.647
15.150
23.446
31.998
35.396
28.911
34.037
21.408
12.601
13.224
14.073
14.017
14.187
15.291
15.206
16.311
14.442
15.857
15.801
15.121
19
3
23
11
q
8
12
3
3
12
10
14
19
3
23
11
9
8
1?
3
13
12
10
14
18.604
23.928
18.293
18.604
9.175
15.433
27.722
21.577 31
47.006
26.051
34.830
20.303
12.743
12.459
14.102
14.073
14.045
15.291
15.234
15.631 31
20.671 15
16.424
16.424
15.065







43.891











14.640
20.671




-------
                                    TRIBUTARY FLOW  INFORMATION FOR  IDAHO
                                                                              08/33/76
LAKE CODE 1607
       ISLAND PARK RES.
     MEAN MONTHLY FLOWS AND DAILY FLOWS(CMS)
TRIBUTARY




160791
1607C1
1607D1
1607E1
MONTH
        YEAR
10
11
12
1
2
3
4
5
6
7
8
9
10
11
12
1
2
3
4
5
6
7
9
9
10
11
12
i
2
3
4
5
6
7
8
9
10
11
12
1
2
3
4
5
6
7
B
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
MEAN FLOW  DAY
                                       FLOW  DAY
                                         FLOW  DAY
FLOW
0.340
0.311
0.311
0.283
0.229
0.201
0.190
0.850
3.540
2.209
0.481
0.340
0.071
0.068
0.065
0.054
0.040
0.031
0.028
0.340
3.398
1.586
0.127
0.074
0.623
0.623
0.623
0.566
0.510
0.453
0.453
1.161
2.917
2.180
0.793
0.651
2.435
2.407
2.379
2.237
2.067
1.954
1.897
3.710
6.881
5.635
2.860
2*464
19
3
23
11
9
8
12
31
13
12
10
14
19
3
23
11
9
8
12
31
13
12
10
14
19
3
23
11
9
'B
12
31
13
12
10
14
19
3
23
11
9
P
12
31
13
12
10
14
0.227
0.227
0.283
0.255
0.227
0.227
0.170
2.549
9.628
1.756
0.453
0.227
0.057
0.057
0.057
0.057
0.028
0.028
0.028
2.860
3.653
2.464
0.113
0.057
0.623
0.623
0.566
0.538
0.510
0.481
0.425
2.718
3.002
2.577
0.765
0.623
3.115
2.662
2.294
2.209
2.124
2.010
1.841
5.097
20.105
2.662
2.237
2.237
                                                           15
                                                        3.964

-------
        APPENDIX C



PHYSICAL AND CHEMICAL DATA

-------
STORET RETRIEVAL DATE 76/08/35
NATL EUTROPHICATION SURVEY
EPA-LAS VEGAS
 160701
44 23 41.0 111 33 13.0 3
ISLAND PARK RESERVOIR
16043   IDAHO
                                                                 11EPALES  751117      2111303
                                                                  0014 FEET  DEPTH  CLASS  00
  DATE   TIME DEPTH  WATER
  FROM    OF
   TO    DAY  FEET

75/07/30 09 30 0000
         09 30 000*=;
         09 30 0010
75/09/03 09 30 0000
         09 30 0005
75/10/30 11 15 0000
         11 15 0005
  DATE   TIME DEPTH
  FROM    OF
   TO    DAY  FEET

75/07/30 09 30 0000
         09 30 0005
         09 30 0010
75/09/03 09 30 0000
         09 30 0005
75/10/30 11 15 0000
         11 15 0005
0010
TER
EMP
ENT
16.8
17.0
16.9
15.0
15.0
8.5
8.4
0665
S-TOT

/L P
0.023
0.028
0.034
0.124
0.123
0.056
0.077
00300
DO

MG/L
9.0
8.2
7.8
5.2
5.0
9.1
7.1
32317
CHLRPHYL
A
UG/L
2.8


5.3

0.9

00077
TRANSP
SECCHI
INCHES
146


44

96

00031
INCDT LT
RFMNING
PERCENT







00094
CNDUCTVY
FIELD
MICROMHO
133
134
137
130
130
126
126











00400
PH

SU
9.30
9.30
9.30
6.75
7.75
9.00
8.30











00410
T ALK
CAC03
MG/L
83
80
80
74
77
74
84











00610
NH3-N
TOTAL
MG/L
0.030
0.030
0.030
0.050
0.060
0.040
0.070











00625
TOT KJEL
N
MG/L
0.200
0.200
0.300
0.500
0.500
0.300
0.400











                                      00630      00671
                                   N02&N03    PHOS-DIS
                                   N-TOTAL     0»THO
                                      MG/L      MG/L P
                                       0.030K
                                       0.030K
                                       0.020K
                                       0.100
                                       0.100
                                       0.020K
                                       0.090
0.013
0.011
0.014
0.037
0.027
0.017
0.03ft
         K VALUE KNOWN TO BE LESS
             THAN INDICATED

-------
STORE! RETRIEVAL DATE 76/08/25
NATL EUTROPHICATION SURVEY
EPA-LAS VEGAS
 16070?
44 25 37.0 111 27 20.0 3
ISLAND PARK RESERVOIR
16043   IDAHO
                                                                 11EPALES  751117     2111202
                                                                  0053 FEET  DEPTH  CLASS 00

DATE
FROM
TO
75/07/30



75/09/03





75/10/20




DATE
FROM
TO

TIME DEPTH
OF
DAY FEET
10 00 0000
10 00 0005
10 00 0030
10 00 0049
09 55 0000
09 55 0005
09 55 0015
09 55 0030
09 55 0045
10 20 0005
11 00 0000
11 00 0005
11 00 0016
11 00 0040

TIME DtPTH
OF
DAY FEET
00010
WATER
TEMP
CENT
17.6
17.7
11.1
8.5
16.3
16.2
16.1
15.8
14.1

9.9
9.8
9.7
8.8
00665
PHOS-TOT

MG/L P
00300
DO

MG/L
9.2
8.8
4.0
3.2
9.2
9.0
9.2
9.0
8.0

8.4
8.8
8.4
6.4
32217
CHLRPHYL
A
UG/L
00077 00094
TRANSP CNDUCTVY
SECCHI FIELD
INCHES MICROMHO
168 145
139
116
105
52 121
123
121
120
108

120 106
111
107
106
00031
INCDT LT
RF.MNING
PERCENT K VALUE
00400
PH

SU
9.30
9.40
8.60
8.40
9.00
9.10
9.15
9.15
8.85

9.00
9.00
8.70
8.45



KNOWN TO BE
00410
T ALK
CAC03
MG/L
74
73
68
62
68
68
70
73
66
72
68
68
68
73



LESS
00610
NH3-N
TOTAL
MG/L
0.020
0.020
0.060
0.160
0.040
0.030
0.020
0.040
0.050
0.020K
0.020
0.040
0.060
0.070




00625
TOT KJEL
N
MG/L
0.400
0.200K
0.200K
0.200
0.400
0.400
0.300
0.500
0.300
0.200
0.200
0.300
0.300
0.300




00630
N02S.N03
N-TOT4L
MG/L
0.020K
0.020K
0.020
0.040
0.020K
0.020K
0.020K
0.020K
0.020K
0.020K
0.020K
0.020K
0.020K
0.040




00671
PHOS-DIS
ORTHO
MG/L P
0.012
0.012
0.034
0.066
0.008
0.011
0.012
0.012
0.013
0.004
0.00$
0.018
0.021
0.029




THAN INDICATED
75/07/30



75/09/03





75/10/20



10 00 0000
10 00 0005
10 00 0030
10 00 0049
09 55 0000
09 55 0005
09 55 0015
09 55 0030
09 55 0045
10 20 0005
11 00 0000
11 00 0005
11 00 0016
11 00 0040
0.019
0.018
0.04]
0.105
0.062
0.063
0.024
0.032
0.035
0.029
0.037
0.055
0.052
0.089
2.3



18.7





19.6






































































































-------
STORET RETRIEVAL DATE  76/08/35
NATL EUTROPHICATION SURVEY
EPA-LAS VEGAS
                          160703
                         44 35 12.0 111 23 42.0 3
                         ISLAND PARK RESERVOIR
                         16043   IDAHO
                                                                  11EPALES  751117     3111202
                                                                   0073 FEET  DEPTH  CLASS 00
DATE
FROM
TO
75/07/30




75/09/03




75/10/20



00010
TIME DEPTH *ATER
OF TEMP
DAY FEET
10
10
10
10
10
10
10
10
10
10
10
10
10
10
15
15
15
15
15
20
20
20
20
20
30
30
30
30
0000
0005
0020
0045
0069
0000
0005
0015
0040
0064
0000
0005
0021
0051
CENT
17.8
17.8
13.2
8.8
6.3
16.6

16.5
15.8
13.6
10.2
10.2
10.1
8.8
00300
DO
MG/L
6.8
8.6
7.2
4.8
2.2
8.8

8.2
8.4
5.4
8.5
8.6
7.9
7.4
00300
DO

MG/L
6.8
8.6
7.2
4.8
2.2
6.8

8.2
8.4
5.4
8.5
8.6
7.9
7.4
00077
TRANSP
SECCHI
INCHES
132




96




120



00094
CNDUCTVY
FIELD
MICROMHO
135
132
123
102
93
120

120
119
117
118
89
105
97
00400
PH

SU
9.30
9.20
7.90
7.80
8.10
9.10

9.10
9.10
8.30
9.00
9.10
8.70
8.50
00410
T ALK
CAC03
MG/L
71
70
64
61
60
72
72
71
72
74
66
68
67
63
00610
NH3-N
TOTAL
MG/L
0.030
0.020
0.030
0.060
0.400
0.0?0
0.020K
0.020
0.020
0.210
0.020K
0.020K
0.050
0.070
00625
TOT KJEL
N
MG/L
0.200K
0.300
0.200K
0.200K
0.500
0.200
0.200
0.200
0.300
0.400
0.300
0.200
0.200
0.200
00630
N02&N03
N-TOTAL
MG/L
0.020K
0.020K
0.020K
0.020
0.020
0.020K
0.020K
0.020K
0.020K
0.020K
0.020K
0.020K
0.020K
0.020K
00671
PHOS-DIS
ORTHO
MG/L P
0.014
0.012
0.012
0.024
0.134
0.005
0.004
0.003
0.004
0.032
O.OOS
0.010
0.014
0.018
                       00665      32217
  DATE   TIME DEPTH  PHOS-TOT   CHLRPHYL
  FROM    OF                      A
   TO    DAY  FEET    MG/L  P      UG/L

75/07/30 10  15  0000     0.022        5.1
         10  15  0005     0.019
         10  15  0020     0.017
         10  15  0045     0.030
         10  15  0069     0.258
75/09/03 10  20  0000     0.017       26.3
         10  20  0005     0.029
         10  20  0015     0.020
         10  20  0040     0.016
         10  20  0064     0.052
75/10/20 10  30  0000     0.029        2.9
         10  30  0005     0.034
         10  30  0021     0.037
         10  30  0051     0.044
  00031
INCDT LT
RF.MNING
PERCENT
K VALUE KNOWN TO BE LESS
    THAN  INDICATED

-------
       APPENDIX D

TRIBUTARY AND WASTEWATER
  TREATMENT PLANT DATA

-------
STORET RETRIEVAL DATE'76/08/25
NATU EUTROPHICATION SURVEY
EPA- LAS VEGAS
  DATE   TIME DEPTH N024.N03
  FROM    OF
   TO    DAY  FEET
74/10/19
74/11/03
75/01/11
75/02/09
75/03/08
75/04/12
75/05/03
75/05/31
75/06/03
75/07/12
75/08/10
75/09/14
12 47
11 15
15 32
12 38
11 15
11 00
09 00
11 40
11 50
12 10
10 00
12 10
                                                          1607A1
                                                         44 25 05.0 111 23 43.0 4
                                                         HENRYS FORK
                                                         16      7.5 ISLAND PK DM
                                                         0/ISLANO PARK RESERVOIR  130691
                                                         BELO DAM 4.5 MI H OF RT 20/191 JCT
                                                         11EPALES             2111204
                                                          0000 FEET  DEPTH  CLASS 00
0630
&N03
OTAL
G/L
0.040
0.024
0.072
0.112
0.155
0.100
0.120
0.005
0.010
0.005
0.015
0.055
00625
TOT KJEL
N
M6/L
0.300
0.650
0.300
0.700
0.350
2.700
1.950
1.050
1.150
0.500
0.300
0.500
00610
NH3-N
TOTAL
MG/L
0.050
0.050
0.060
0.112
0.025
0.055
0.060
0.025
0.015
0.015
0.070
0.110
00671
PHOS-DIS
ORTHO
MG/L P
0.015
0.035
0.030
0.032
0.030
0.030
0.020
0.005K
0.014
0.010
0.050
0.075
00665
PHOS-TOT

MG/L P
0.025
0.035
0.050
0.060
0.040
0.030
0.060
0.025
0.030
0.020
0.060
0.080
      K VALUE KNOWN TO BE LESS
          THAN INDICATED

-------
STORET RETRIEVAL DATE 76/08/25
NATL EUTROPHICATIOM SURVEY
EPA_ LAS VEGAS
  DATE   TIME DEPTH N02&N03
  FROM     OF
   TO    DAY   FEET
74/10/19
74/11/03
75/01/11
75/03/08
75/04/12
75/05/03
75/06/13
75/06/15
75/07/12
75/08/10
75/09/14
14
10
15
11
11
09
12
11
12
11
11
10
40
10
48
34
50
30
45
45
40
30
 1607A2
44 29 25.0 111 23 52.0 4
HENRYS FORK
16      7.5 ISLAND PK DM
T/ISLAND PARK RESERVOIR  130691
8NK 300 FT V END RD BY LWR COFFE POT CMP
11EPALES             2111204
 0000 FEET  DEPTH  CLASS 00
0630
&N03
OTAL
G/L
0.040
0.024
0.07E
0.060
0.070
0.030
0.010

0.005
0.005
0.035
00625
TOT KJEL
N
MG/L
0.300
0.300
0.200
0.150
1.250
0.350
1.200
1.500
0.450
0.500
0.800
00610
MH3-N
TOTAL
MG/L
0.015
0.020
0.020
0.015
0.030
0.040
0.030
0.090
0.015
0.045
0.020
00671
PHOS-DIS
ORTHO
MG/L P
0.005K
0.005K
0.005
0.005
0.010
0.005
0.015

0.025
0.005
0.040
00665
PHOS-TOT

MG/L P
0.010
0.005K
0.020
0.010K
0.010
0.070
0.020

0.025
0.010K
0.040
           K VALUE KNOWN TO BE LESS
               THAN INDICATED  -

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

74/10/19 15 40
74/11/03 10 20
75/05/31 12 10
75/06/13 13 00
75/07/12 13 13
75/08/10 11 05
75/09/14 09 55
 1607B1
44 27 38.0 111 26 45.0 4
HOTEL CREEK
16      7.5 ISLAND PK DM
T/ISLAND PARK RESERVOIR   130691
SEC RD 8RDG 2 HI W HCCREA  BRDG  CMP
11EPALES             2111204
 0000 FEET  DEPTH  CLASS  00
0630
&.N03
OTAL
IG/L
0.024
0.008
0.065
0.035
0.030
0.015
0.045
00625
TOT KJEL
N
MG/L
0.100
0.100K
1.700
0.500
0.500
0.250
0.750
00610
NH3-N
TOTAL
MG/L
0.010
o.oao
0.045
0.015
0.025
0.005K
0.015
00671
PHOS-DIS
ORTHO
MG/L P
o.oao
0.030
0.025
0.025
0.025
0.015
0.057
00665
PHOS-TOT

MG/L P
0.025
0.030
0.070
0.050
0.040
0.015
0.060
             K VALUE KNOWN TO BE LESS
                 THAN INDICATED

-------
STORET RETRIEVAL DATE 76/08/25
NATL EUTROPHICATION SURVEY
EPA- LAS VEGAS
  DATE   TIME DEPTH N02&N03
  FROM    OF
   TO    DAY  FEET
74/10/19
74/11/03
75/01/11
75/02/09
75/05/31
75/06/13
75/06/15
75/07/12
75/08/10
75/09/14
16 10
10 15
14 35
11 30
12 20
13 15
11 40
13 40
11 15
10 10
                                                         1607C1
                                                        44 27 03.0 111 28 12.0 4
                                                        SHEEP CREEK
                                                        16      7.5 ISLAND PK DM
                                                        T/ISLAND PARK RESERVOIR  130691
                                                        SEC RD BRDG 4 MI WSW OF MCCREA BROG CMP
                                                        11EPALES             2111204
                                                         0000 FEET  DEPTH  CLASS 00
0630
«,N03
OTftL
G/L
0.016
0.008
0.128
0.128
0.090
0.010

0.010
0.005
0.030
00625
TOT KJEL
N
MG/L
0.400
0.400
0.500
0.500
1.900
1.300
1.700
0.300
0.300
1.000
00610
NH3-N
TOTAL
MG/L
0.020
0.025
0.075
0.096
0.050
0.025
0.260
0.020
0.025
0.015
00671
PHOS-DIS
ORTHO
MG/L P
0.010
0.020
0.030
0.024
0.055
0.025

0.020
0.030
0.050
00665
PHOS-TOT

MG/L P
0.025
0.025
0.050
0.060
0.100
0.070

0.070
0.050
0.050

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

74/10/19 16 40
74/11/03 10 00
75/05/31 12 45
75/06/13 13 40
75/07/12 14 00
75/08/10 11 35
75/09/14 10 30
 1607D1
44 25 05.0 111 34 57.0 4
ICEHOUSE CREEK
16      7.5 ICEHOUSE CRK
T/ISLAND PARK RESERVOIR  130*91
SEC RD 8ROG 1.1 Ml E OF COUNTY LINE
11EPALES             2111204
 oooo FEET  DEPTH  CLASS oo
0630
&.N03
OTAL
G/L
0.024
0.048
0.230
0.165
0.095
0.045
0.050
00625
TOT KJEL
N
MG/L
0.700
0.200
0.600
0.850
0.550
0.600
0.400
00610
NH3-N
TOTAL
MG/L
0.015
0.020
0.025
0.020
0.025
0.025
0.010
00671
PHOS-DIS
ORTHO
MG/L P
0.005
0.020
0.025
0.020
0.020
0.015
0.035
00665
PHOS-TOT

MG/L P
0.015
0.035
0.050
0.070
0.035
0.015
0.040

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STORET RETRIEVAL DATE  76/08/25
NATL EUTROPHICATION  SURVEY
EPA- LAS VEGAS
  DATE   TIME DEPTH  NO?S.N03
  FROM    OF
   TO    DAY  FEET

74/10/1*) 16 55
74/11/03 10 05
75/05/31 12 50
75/06/13 13 55
75/07/12 14 20
75/08/10 12 00
75/09/14 10 45
 1607E1
44 34 42.0 111 35 48.0 4
SHERIDAN CREEK
16      7.5 ICEHOUSE CRK
T/ISLAMD PARK RESERVOIR  130691
GRN CYN RO BRDG 1 MI F OF COUNTY LINE
11EPALES             2111204
 0000 FEET  DEPTH  CLASS 00
0630
S.N03
OTAL
G/L
0.016
0.008
0.045
0.005
0.015
0.005
0.030
00625
TOT KJEL
N
MG/L
0.600
0.200
0.400
1.150
0.600
0.600
1.000
00610
NH3-N
TOTAL
MG/L
0.020
0.015
0.020
0.020
0.025
0.025
0.015
00671
PHOS-DIS
ORTHO
MG/L P
0.005K
0.005
0.045
0.045
0.065
0.015
0.030
00665
PHOS-TOT

MG/L P
0.010
0.010
0.120
0.130
0.100
0.020
0.040
                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  OWOHSHAK RESERVOIR

1605  HAUSER

1606  HAYDEN LAKE

1607  ISLAND PARK RESERVOIR

1603  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
INORG 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
8.031
10.391
2.420
11.112
2.787
9.322
25.389
7.322
2.067
4.600
2.318
4.986
15-
MIN 00
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
MEDL
DISS ORTI
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    OISS 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 ( 11)     17 (  1>    25 (  3)    83 ( 10)    100 ( 12)     50 (  5)

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

1606  hAYOEN LAKE                       96 ( 11)     96 ( 11)    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)    SO (  6)     21 (  2)      6 (  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  LOWER TWIN LAKES                  75 (9)     71 (  8) .   58 (  7)    92 ( 11)     42 (5)     50 (  5)

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

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