U.S. ENVIRONMENTAL PROTECTION AGENCY
           NATIONAL EUTROPHICATION SURVEY
                    WORKING PAPER SERIES
                                        REPORT
                                          ON
                                       GREEN LAKE
                                       KING COUNTY
                                       WASHINGTON
                                      EPA REGION X
                                   WORKING PAPER No, 868
 CORVALLIS ENVIRONMENTAL RESEARCH LABORATORY - CORVALLIS, OREGON
                             and
ENVIRONMENTAL MONITORING & SUPPORT LABORATORY - LAS VEGAS, NEVADA

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                              REPORT
                                ON

                            KING COUNTY
                            WASHINGTON
                           EPA REGION X
                       WORKING PAPER No, 868
  WITH THE COOPERATION OF THE
WASHINGTON DEPARTMENT OF ECOLOGY
             AND THE
    WASHINGTON NATIONAL GUARD
           JULY, 1977

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            REPORT ON GREEN LAKE

           KING COUNTY, WASHINGTON

                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. 868
     OFFICE OF RESEARCH AND DEVELOPMENT
    U.S.  ENVIRONMENTAL PROTECTION AGENCY

                 July 1977

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                               CONTENTS

                                                       Page
Foreword                                                i i
List of Washington Study Lakes                          iv
Lake and Drainage Area Map                               v
Sections
  I.  Introduction                                       1
 II.  Conclusions                                        1
III.  Lake Characteristics                               3
 IV.  Lake Water Quality Summary                         4
  V.  Literature Reviewed                               10
 VI.  Appendices                                        11

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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 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 nonpolnt 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.
                                                                t
     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 eutrophlcatlon 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 1s formatted to provide  state
environmental agencies with specific Information for basin
planning [§303(e)], water quality criteria/standards review
[§303(cj], 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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     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 Washington Department of
Ecology for professional involvement, to the Washington National
Guard for conducting the tributary sampling phase of the Survey,
and to those Washington wastewater treatment plant operators who
provided effluent samples and flow data.

     Ms. Barbara Blau, Lake Restoration Program, and the staff
of the Washington Department of Ecology, Lake Restoration Program,
provided invaluable lake documentation and counsel during the
Survey, reviewed the preliminary reports and provided critiques
most useful in the preparation of this Working Paper Series.

     Major General Howard S. McGee, Adjutant General of Washington,
and Project Officer Colonel Clinton C. Johnson, who directed the
volunteer efforts of the Washington National Guardsmen, are also
gratefully acknowledged for their assistance to the Survey.

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                                 iv
LAKE NAME
                    NATIONAL EUTROPHICATION SURVEY
                              STUDY LAKES
                          STATE OF WASHINGTON
American Lake
Banks Lake
Chelan Lake
Diamond Lake
Green Lake
Keechelus Lake
Mayfield Lake
Medical Lake
Moses Lake
Ozette Lake
Sammamish Lake
Lake Whatcom
Lower Granite Reservoir
  COUNTY
Pierce
Grant, Douglas
Chelan
Pend Oreille
King
Kittitas
Lewis
Spokane
Grant
Clallam
Ki ng
Whatcom
Garfield, Whatcom

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                                                            GREEN LAKE
Woodland  Park
X  Lake Sampling Site
                                         Wash.

                                         .—•"•
                                      Map Location

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                   REPORT ON GREEN LAKE,  WASHINGTON
                            STORET NO.  5305

I.    INTRODUCTION
          Green Lake was included in the  National  Eutrophication  Survey
     (NES) as a water body of special  interest to  the Washington  State
     Department of Ecology.   Tributaries  and nutrient sources  were not
     sampled, and this report relates  only to lake sampling data.
II.   CONCLUSIONS
     A.   Trophic Condition:*
               Survey data indicate that  Green Lake  is eutrophic,  i.e.,.
          nutrient rich and highly productive.  Whether such nutrient
          enrichment is to be considered  beneficial  or deleterious is
          determined by its actual or potential  impact upon designated
          beneficial water uses of each lake.  Chlorophyll  a_ values in
          the lake ranged from 0.4 yg/1 in April to  5.5 yg/1 in July,
          with a mean of 3.0 vig/1.  Potential for  primary productivity
          as measured by algal assay control yields  was high.   Of the
          13 Washington lakes sampled in  1975, 3 had higher median total
          phosphorus values (0.027 mg/1), 10 had higher median inorganic
          nitrogen values (0.050 mg/1)  and 5 had higher median ortho-
          phosphorus levels (0.009 mg/1)  than Green  Lake.

     *See Appendix C.

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          Survey limnologists reported some emergent and floating macro-
     phytes during the July sampling,  and submerged weeds were noted
     during October.   Ketelle and Uttormark (1971)  report that although
     Green Lake is naturally eutrophic, the addition of low nutrient
     city water to the lake has resulted in improved water quality and
     fewer nuisance blue-green algal  blooms.
B.   Rate-Limiting Nutrient:
          The algal assay results indicate that Green Lake was limited
     by available phosphorus during the spring (04/01/75) and autumn
     (10/29/75) samplings.   Lake data  suggest nitrogen limitation in
     the spring and summer and phosphorus limitation in the fall.

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III.  LAKE CHARACTERISTICS
     A.    Lake Morphometry:*
                                     2
          1.    Surface area:  1.04 km .
          2.    Mean depth:   3.8 meters.
          3.    Maximum depth:   8.8 meters.
          4.    Volume:  3.952  x 106 m3.
     B.    Precipitation:
          1.    Year of sampling:  109.6  cm.
          2.    Mean annual:   90.6 cm.
     *0tt, Charles R.,  I960.

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IV.   LAKE WATER QUALITY SUMMARY
          Green Lake was sampled three times  during  the  open-water  season
     of 1975 by means of a pontoon-equipped Huey  helicopter.   Each  time,
     samples for physical  and chemical parameters were collected  from
     two stations on the lake and from a  number of depths  at  each station
     (see map,  page v).  During  each  visit, depth-integrated  samples were
     collected  from each station for  chlorophyll  ^analysis and phyto-
     plankton identification and enumeration.   During the  first and last
     visits, 18.9-liter depth-integrated  samples  were composited  for algal
     assays. Maximum depths sampled  were 5.5 meters at  Station 01, and
     3.4 meters at Station 02.  For a more detailed  explanation of  NES
     methods, see NES Working Paper No. 175.
          The results obtained are presented  in full in  Appendix  B  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 a_ determinations are included in III-B.  Results of the
     limiting nutrient study are presented in III-C.

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                                     -/  1/7", )
•r-rsicAL AND CHEMICAL CHARACTERISTICS

                 (   7/13/75 )
(  10/29/75 )
PABA«ETFP
TEMOEU4TIJEE: u^.fi Cr,r,
n , — 1 . = v n E P T '-i 3
UAXDFPTH-*0 ?
DIS?">LVF.O oxYiirf. C'G/! >
n.-i.5 M DE&TH 3
WAX .JFPTWto ?
CONDUCTIVITY (ijMHOC)
O.-l .5 M OEPTH 3
"AX OEPTH"* 7
O.-l .S M OF.PTH 3
MA" DF.PTH»» ?
TOTAL ALKALINITY <"G/L>
O.-l .^ M Lifi-Tri 3
MAX DEPTH** 2
TOTAL P (MG/L)
O.-l .S M DEPTH 3
*A* OF.°TH»* ?.
DISSOLVED OwTHO P (wr,/D
O.-l.- M DEPTH 3
MAX DFPTH»» ?
N02+NO3 ("fi/l )
fl.-l.^ '" TE^TH 3
"A< OFPTH»« 7
AMMONIA (MG/L)
O.-l. 5 M DEPTH 3
MA* OF.PTH** ?
KJELCAHL f-i (MCi/Ll
0.- 1 .S M nE^TH 3
••'•AX OFPTrt«» 2
S'*'' = '

*.'-•- 9. A -<.6
'-).4- 9.6 9.S

11.6- 1?." 11. fc,
! 1 .?- 11 -11 1 1 .t

49.- 50. 50.
52.- «-4. 5S.
7.3- 7.6 7.4
7.3- 7.4 7.4

? 1 . - 2 4 . ? 4 ,
!«.- 24. ?1 .

0.027-0.050 O.mj
^.033-0.05^. n.f<4^

n. 004-n. 009 0 . n n b
o.nos-p.o05 o.oob

(>.0?0-0. 03(i y.n?n
0.0?0-0.0?0 !'.r; °U

0. 0^0-0. 05fl 0 . O^U
0.030-0.03'! 0 . 1 3 0
0.500-1.50!) 0.5mj
2.300-0.510 0.40 (i
( -EU-^)

'1.0- I . 5
'.1- J.4

o.O- l.S
?.l- 3.4

n.O- 1.5
?.l- 3.4
0.0- 1.5
2.1- 3.4

" .0- 1.5
2.1- 3.4

0.0- 1.5
? . ! - 3.4

0.0- 1 .S
? . 1 - 3.4

n.O- 1.5
2.1- 3.4

1.0- 1.5
2.1- 3.4
o.n- i .^
'.1- 3.4
^AN

3 1 * . 2 -
c 1H.3-

3 4.4-
2 rt .H-

3 21 .-
2 20.-
3 7.8-
2 7.7-

3 ??.-
? 22.-

3 O.Ol^-O
2 0.019-0

? 0.013-0
2 0.014-0

3 0.020-0
2 n. 020-0

3 0.030-0
2 0.020-0
3 0. 3 00-0
2 O.?00-0
s*»»

19.2
IB. 4

9.0
9.0

35.
25.
8.1
7.8

26.
23.

.026
.020

.016
.016

.020
.020

.030
.040
.900
.500
= ?
MEDIAN

19.2
1*.3

3.8
3.9

33.
23.
8.0
7.8

23.
23.

0.020
0.019

0.016
0.015

0.020
0.020

0.030
0.030
0.600
0.350
MAX
OEPTH
WANGF;
(METE

0.0-
2.1-

0.0-
2.1-

0.0-
2.1-
0.0-
2.1-

0.0-
2.1-

0.0-
2.1-

0.0-
2.1-

o.o-
2.1-

o.o-
2.1-
0.0-
2.1-
HS)

1.5
5.5

1.5
5.5

1.5
5.5
1.5
5.5

1.5
S.5

1.5
5.5

1.5
5.5

1.5
5.5

1.5
5.5
1.5
5.5
N*

3
2

3
2

3
2
3
2

3
2

3
?

3
2

3
2

3
2
3
2
RANGE

12.2- 12.3
12.2- 12.3

9.8- 10.4
9.8- 9.8

31.- 34.
31.- 32.
7.1- 7.2
7.1- 7.1

19.- 21.
20.- 22.

0.023-0.036
0.028-0.070

0.005-0.010
0.002-0.009

0.060-0.060
0.060-0.060

0.0«0-0.080
0.070-0.090
0.200-0.200
0.200-0.300
= 2
MEDIAN

12.2
12.2

10.0
9.8

32.
32.
7.1
7.1

20.
21.

0.026
0.049

0.006
0.005

0.060
0.060

0.080
0.080
0.200
0.250
MAX
DEPTH
PANGE
(METEPS)

0.0-
2.1-

0.0-
2.1-

0.0-
2.1-
0.0-
2.1-

0.0-
2.1-

0.0-
2.1-

0.0-
2.1-

0.0-
2.1-

0.0-
2.1-
0.0-
2.1-

1.5
3.4

1.5
3.4

1.5
3.4
1.5
3.4

1.5
3.4

1.5
3.4

1.5
3.4

1.5
3.4

1.5
3.4
1.5
3.4
SeCCHI DI=C
                            1.?-
                                                                 2.7-  2.7    2.7
                                                2.4-  2.4    2.4
                             MAXIMUM  Ot-T~: .lA-'^LKO AT EACH
                              s  =  ,MO.  OF StTtS CAMPLED ON THI1^  HATE

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B.   Biological  Characteristics:

     1.    Phytoplankton -
          Sampling
          Date

          04/01/75
          07/18/75
          10/29/75
Dominant
Genera

1.  Asterionella
2.  Aphanizomenon
3.  Fragilaria
4.  Flagellate
5.  Centric Diatom

    Other genera

         Total
1.
2.
3.
4.
5.
Microcystis
Oscillatoria
Cyclotella
Chroomonas
Closterium
1.
2.
3.
4.
5.
Other genera

     Total

Asterionella
Chrysophytan
Anabaena
Fragilaria
Aphanizomenon

Other genera

     Total
Algal
Units
per ml

 3,960
 2,487
 1,301
   287
    57

   192

 8,284

   341
   341
   189
   114
    38

	37_

 1,060

   676
   204
   157
   157
    94

   158

 1,446

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

     04/01/75                   01                     0.6
                                02                     0.4

     07/18/75                   01                     2.0
                                02                     5.5

     10/29/75                   01                     4.5
                                02                     4.9

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C.   Limiting Nutrient Study:

     1.   Autoclaved,  filtered,  and nutrient spiked

          a.   04/01/75
          Spike (mg/1)

          Control
          0.05 P
          0.05 P + 1.0 N
          1.00 N

          b.    10/29/75
Ortho P
Cone, (mg/1)

  0.009
  0.059
  0.059
  0.009
          Spike (mg/1)

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

  0.010
  0.060
  0.060
  0.010
Inorganic N
Cone, (mg/1)

  0.044
  0.044
  1.044
  1.044
Inorganic N
Cone, (mg/1)

  0.140
  0.140
  1.140
  1.140
Maximum yield
(mg/1-dry wt.)

     0.8
     3.6
    20.6
     0.8
Maximum yield
(mg/1-dry wt.)

     2.9
     6.1
    30.5
     3.5

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2.    Discussion -
          The control  yields of the assay alga,  Selenastrum capri-
     cornutum. indicate that the potential  for primary  productivity
     in Green Lake was moderate during spring  sampling  (04/01/75)
     and high at the time of autumn sample collection  (10/29/75).
     In both assays, a significant increase in yield over that of
     the control occurred when phosphorus was  added alone and  in
     combination with nitrogen, indicating phosphorus  limitation.
     The addition of nitrogen alone did not produce a  significant
     growth increase beyond that of the control.
          The mean inorganic nitrogen to orthophosphorus  (N/P)
     ratios in the lake data were approximately 11/1,  3/1, and 24/1
     in the spring, summer, and fall, respectively, suggesting
     primary limitation by nitrogen in the spring and  summer,  and
     phosphorus limitation in the fall (a mean N/P ratio  of 14/1
     or greater generally reflects phosphorus  limitation).

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                                  10
V.   LITERATURE REVIEWED

     Ketelle, Martha J.  and Paul  D.  Uttormark.   1971.   Problem Lakes in
       the United States.   U.S.  Environmental  Protection Agency Project
       #16010EHR.  University of Wisconsin, Madison, Wisconsin.

     Ott, Charles R.  1960.  A Study of the Environmental Factors
       Affecting the Eutrophication  of Green Lake.   MS Thesis, Civil
       Engineering Department, University of Washington, Seattle,
       Washington.

     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,  Con/all is,
       Oregon.

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                                11




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 35.315 = cubic feet/sec
Centimeters x 0.3937 = inches
Kilograms x 2.205 = pounds
Kilograms/square kilometer x 5.711 = Ibs/square mile

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        APPENDIX B



PHYSICAL AND CHEMICAL DATA

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  STORE! RETRIEVAL OATF 76/11/16
  NATL FUTROPHIC4TIO^ SURVEY
  EPA-LAS VEGAS
                                                                     530501
                                                                    47  45 5?.0 122 20 15.0  3
                                                                    GREEN LAKE
                                                                    53033   WASHINGTON
                                                                       0015 FEET  DEPTH  CL«SS 00
75/04/01 10 45
         10 45
         10 45  0011
75/07/18 08 35  0000
         08 35  0005
         na 35  001«
75/10/29 12 35  0000
         12 35  0007
                       00010
  DATE   TI»*E OEPT^1
  FPOM    OF
   TO    DAY  FFET     CFNT
9.6
9.5
9.4
19.2
19.2
18.4
12.3
12.3
1 1 .6
11.6
1 1.8
9.0
4.4
9.0
9.8
9.8
                                   00300      00077     00094
                                    oo       TRANSP   CNDUC
                                             cECCHI   FIELD
                                             INCHES   MICRO!
                                                 108
                                                  96
14
VY

IHO
49
50
64
35
33
25
32
32
00400
PM

su
7.60
7.40
7.35
8.10
R.OO
7.70
7.20
7.15
00410
T ALK
CAC03
M&/L
24
24
24
23
22
22
19
20
00610
NH3-N
TOTAL
MG/L
0.030
0.050
0.030
0.030
0.030
0.040
0.080
0.090
00^25
TOT KJEL
N
MG/L
0.500
0.500
0.500
0.600
0.300
0.200
0.200
0.200
006TO
N02&N03
N-TOTAL
MG/l
0.020K
0.030
0.020K
0.020K
0.020K
0.020K
0.060
0.060
00671
PHOS-OIS
O«TMO
MG/L P
0.005
0.009
0.005
0.016J
0.016J
0.014J
0.005
0.002
    DATE   TIME DEPTi-'
    FRO"    OF
     TO    DAY  FF.ET

  75/04/01 10 45  0000
           10 45  0005
           10 45  0011
  75/07/18 08 35  0000
           08 35  000^
           PR 35  001P
  75/10/29 12 35  0000
           12 35  0007
0665
S-TOT

/L P
0.027
0.050
0.056
0.019
0.0?0
0.019
0.023
0.028
32217
CHLRPHYL
A
DG/L
0.6


2.0


4.5

00031
INCDT LT
REMNING
PERCENT








 K VALUE KNOWN TO BE LESS
     THAN INDICATED
J VALUE KNOWN TO BE ESTIMATED

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STORET ^RETRIEVAL  D«TE
NATL FUTROPrtlCATION  S'IRVEY
E.PA-LAS VEGAS

DATE
FPOK
TO
75/04/01

75/07/18

75/10/29



TIME DEPTH
OF
OAY FEET
11 15 0000
11 15 0007
08 20 0000
06 20 0007
12 15 0000
12 15 0005
12 15 0011
00010
WATEP
TFMP
CENT
9.6
9.6
18.?
18.3
12.2
12.?
1?.2
 530502
47 40 25.0  122 20 29.0 3
GREEN LAKE
53033   WASHINGTON
                                                                                              131191
11EPALES

00300
DO

"G/L
12.0
11.2
8.8
«.8
10.0
10.4
9.8

00077
THANSP
SECCHI
INCHED
54

108

96



00094
CNOUCTVY
FIELD
MICPOMHO
50
52
21
20
34
31
31
noil
00400
PH

su
7.35
7.40
7.80
7.85
7.15
7.10
7.10
211
i FEET OE»TH CLASS
00410
T ALK
CAC03
MG/L
21
18
26
23
20
21
22
00610
NH3-N
TOTAL
MG/L
0.030
0.030
0.030
0.020
0.080
0.080
0.070
1202
On
00625
TOT KJEL
N
MG/L
0.500
0.300
0.900
0.500
0.200
0.200
0.300
                                                                                                          006^0      f>0671
                                                                                                        N02&NO3   PHOS-niS
                                                                                                        N-TOTAL     ORTHO
                                                                                                          MG/L      MG/L P
                                                                                                           0.020K
                                                                                                           0.020K
                                                                                                           0.020
                                                                                                           0.020K
                                                                                                           0.060
                                                                                                           0.060
                                                                                                           0.060
                                                  0.004
                                                  0.005
                                                  0.013J
                                                  0.016J
                                                  0.010
                                                  0.006
                                                  0.009
  DATE
   TO
          OF
         DAY
75/04/01 11 15 0000
         11
75/07/18 08 20 0000
         08 20 0007
75/10/29 12 15 0000
         12 15
         12 l^

EPTH

EET
0000
0007
ooon
0007
ooon
0005
0011
00665
«>HOS~TOT

MG/L P
0.033
0.033
0.026
0.020
0.036
0.026
0.070
32217
CHLftPHYL
A
UG/L
0.4

5.5

4.9


00031
INCDT LT
RFMNING
PERCENT







     K VALUE KNOWN TO BE LESS
         THAN  INDICATED
     J VALUE KNOWN TO BE ESTIMATED

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                            APPENDIX C

                   PARAMETRIC RANKINGS OF LAKES
                      SAMPLED BY NES IN 1975

                        STATE OF WASHINGTON
     Mean or median values for six of the key parameters  evaluated
in establishing the trophic conditions of Washington 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
5301  AMERICAN LAKE
5302  BANKS LAKE
5303  CHELAN LAKE
5304  DIAMOND LAKE
5305  GREEN LAKE
5306  KEECHELUS LAKE
5307  MAYFIELO LAKE
5308  MEDICAL LAKE
5309  MOSES LAKE
5310  07ETTE LAKE
5311  SAMMAMISH LAKE
5312  WHATCOM LAKE
5313  LOWER GRANITE RESERVOIR
MEDIAN
TOTAL P
0.027
0.021
0.005
0.014
0.027
0.007
0.014
0.275
0.115
0.010
0.015
0.009
0.033 .
MEDIAN
INORG N
0.105
0.040
0.070
0.060
0.050
0.040
0.100
0.225
0.150
0.110
0.210
0.320
0.150
500-
MEAN SEC
343.000
364.533
111.900
303.667
415.000
280.250
402.000
401.714
463.600
403.333
374.000
288.000
435.500
MEAN
CHLORA
4.822
7.373 ,
0.905
14.537
2.983
1.400
4.250
16.425
29.060
1.225
7.290
3.422
•4.875
15-
MIN DO
15.000
10.800
6.400
14.200
10.600
9.200
10.600
15.000
14.600
7.200
14.600
10.800
7.200
MEDIA
DISS ORTH
0.007
0.007
0.003
0.010
0.009
0.00?
0.007
0.166
0.038
0.009
0.006
0.009
0.022

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PERCENT OF LAKES WITH HIGHER VALUES (NUMBER OF LAKES WITH HIGHER VALUES)
LAKE
CODE  LAKE NAME

5301  AMERICAN LAKE  .

5302  BANKS LAKE

5303  CHELAN LAKE

5304  DIAMOND LAKE

5305 ,GREFN LAKE

5306  KEECHELUS LAKE

5307  MAYFIELD LAKE

5308  MEDICAL LAKE

5309  MOSES LAKE

5310  07ETTE LAKE

5311  SAMMAMISH LAKE

5312  WHATCOM LAKE

5313  LOWER GRANITE RESERVOIR
MEDIAN
TOTAL P
29 (
42 <
100 <
6? (
29 1
92 1
62 1
0 1
8 1
75 I
50 i
83
17
: 3)
5)
; 12)
: 7)
! 3)
[ 11)
! 7)
: 0)
[ 1)
I 9)
( 6)
( 10)
( 2)
MEDIAN
INORG N
50 <
100 <
67 1
75 1
83 1
92 1
58 I
8 1
29 I
42 i
17
0
29
: 6)
: 12)
: 8)
I 9)
I 10)
: ID
1 7)
! 1)
! 3)
( 5)
( 2)
( 0)
( 3)
500-
MEAN SEC
67 (
58 I
100 (
75 1
17 1
92 1
33 I
42 1
0 1
25 I
50 i
83
8
I 8)
; 7>
: 12)
: 9)
! 2)
[ 11)
1 4)
! 5)
I 0)
[ 3)
( 6)
( 10)
( 1)
MEAN
CHLORA
50 (
25 (
100 <
17 <
75 (
83 1
58 1
8 1
0 1
92 I
33 i
67
42
I 6)
: 3)
: 12)
: 2)
[ 9)
: 10)
[ 7)
[ 1)
I 0)
[ 11)
t 4)
( 8)
( 5)
15-
MIN DO
4 1
46 (
100 (
33 (
62 1
75 1
62 1
4 (
21 1
87 1
21 i
46 <
87
1 ,0)
; 5)
! 12)
! 4)
! 7)
1 9)
t 7)
[ 0)
E 2)
[ 10)
t 2)
( 5)
( 10)
MEDIAN
DISS OPTHO
58 1
71 1
92 1
25 1
46 1
100 I
71 1
0 I
8 I
33 i
S3
46
17
: 7)
i ft)
! 11)
I 3)
t 5)
t 12)
[ -P)
! 0)
I 1)
t 4)
( 10)
( 5)
( 2)

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