U.S. ENVIRONMENTAL PROTECTION AGENCY
NATIONAL EUTROPHICATION SURVEY
WORKING PAPER SERIES
REPORT
ON
FEDICAL LAKE
SPOKANE COUNTY
WASHINGTON
EPA REGION X
WORKING PAPER No, 871
CORVALLIS ENVIRONMENTAL RESEARCH LABORATORY - CORVALLIS, OREGON
and
ENVIRONMENTAL MONITORING & SUPPORT LABORATORY - LAS VEGAS, NEVADA
-------
REPORT
ON
MEDICAL LAKE
SPOKANE COIMY
WASHINGTON
EPA REGION X
WORKING PAPER No, 871
WITH THE COOPERATION OF THE
WASHINGTON DEPARTMENT OF ECOLOGY
AND THE
WASHINGTON NATIONAL GUARD
JULY, 1977
-------
REPORT ON MEDICAL LAKE
SPOKANE 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. 871
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
July 1977
-------
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 11
VI. Appendices 12
-------
ii
FOREWORD
The National EutropMcatlon 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, 1n 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 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 is formatted to provide state
environmental agencies with specific Information for basin
planning [§303(e)L water quality criteria/standards review
[§303(cj], clean lakes [§314(a,b)]t and water quality monitoring
[§106 and §305(b)] activities mandated by the Federal Water
Pollution Control Act Amendments of 1972.
-------
m
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.
-------
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
King
Whatcom
Garfield, Whatcqm
-------
47°35-
Wash.
L~^
Map Location
0
0
MEDICAL LAKE
X Lake Sampling Site
1 J Km>
Scale 1
47°34-
' 117°43'
117°42'
117 41'
117°40
117°39'
47°33'
-------
REPORT ON MEDICAL LAKE, WASHINGTON
STORET NO. 5308
I. INTRODUCTION
Medical 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.
Medical Lake lies adjacent to the west side of the Town of
Medical Lake in Spokane County. There is no surface-water outlet
from the lake (McConnell, et al., 1976); Wolcott (1973) reports
that the oxygen supply is inadequate to support a fish population,
presumably due to a high level of organic material in the water.
Rehabilitation treatments to the lake were applied by the Washington
Department of Game in 1957 (Blau, personal communication).
Present restoration efforts by the Town of Medical Lake include
precipitation of phosphorus to reduce nuisance blue green algae
blooms (Fiedler, personal communication).
II. CONCLUSIONS
A. Trophic Condition:*
Survey data indicate that Medical Lake is hypereutrophic.
Chlorophyll a^ values ranged from a low of 1.5 yg/1 in June
*See Appendix C.
-------
to a high of 36.5 yg/1 in July with a mean of 16.4 yg/1. Secchi
disc visibility in the lake was relatively low on all but the
June sampling date and the potential for primary productivity as
measured by algal assay control yields was extremely high through-
out the sampling year. Of the 13 Washington lakes sampled in 1975,
none had greater total phosphorus levels (0.275 mg/1) or median
dissolved orthophosphorus values (0.166 mg/1), and only one had
higher median inorganic nitrogen levels (0.225 mg/1) than Medical
Lake.
Survey limnologists reported an algal bloom on the July samp-
ling date and emergent macrophytes during June and July. Other
sources (Ketelle and Uttormark, 1971) note that Medical Lake is
highly eutrophic and undergoes large blooms of Anacystis and
Anabaena flos-aguae.
B. Rate-Limiting Nutrient:
Algal assay results indicate that Medical Lake was limited by
available nitrogen levels during the sample collection times
(06/03/75, 09/11/75, 10/22/75). The lake data generally substan-
tiate nitrogen limitation throughout the sampling year.
-------
III. LAKE CHARACTERISTICS
A. Lake Morphometry:*
2
1. Surface area: 0.64 km .
2. Mean depth: 9.7 meters.
3. Maximum depth: 18.3 meters.
4. Volume: 6.241 x 106 m3.
B. Precipitation:
1. Year of sampling: 54.0 cm.
2. Mean annual: 44.2 cm.
*Wolcott, E.E., 1965.
-------
IV. LAKE WATER QUALITY SUMMARY
Medical Lake was sampled four 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 col-
lected 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 chloro-
phyll a_ analysis and phytoplankton identification and enumeration.
During the first, third, and fourth visits, 18.9-liter depth-
integrated samples were composited for algal assays. Maximum
depths sampled were 8.5 meters at Station 01, and 15.5 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 maxi-
mum 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.
-------
MEDICAL
STO=ET C
E 53"°
:^£
IS. 7- 17.9
6.9- 1?.?
7.?- 7.S
0.6- S.?
1406. -1486.
1153. -1269.
9.2- 9.?
9.2- 9.2
900. -1510.
13?0.-1460.
0.351-0.364
0.392-0.570
0.300-0.315
0.347-0.437
0.340-0.350
0. 1?0-0.300
0.280-0.350
0.430-0.730
2.500-R.700
2.700-3.400
= •>
-/>£ TTfir-j
16.9
9.5
7.2
2.9
1450.
1211.
9.?
9.2
1410.
1390.
0.3S6
0.481
0.308
0.392
0.345
O.?10
0.335
0.5*0
2.6SO
3.0SO
"AX
n£PT*
^AfuG1--
(v,tT6:
o.O-
6.1-
0.0-
6.1-
0.0-
6.1-
0.0-
6.1-
0.0-
6.1-
0.0-
6.1-
0.0-
6.1-
0.0-
6.1-
0.0-
6.1-
0.0-
6.1-
-S)
1.5
9.1
1.5
9.1
1.5
9.1
1.5
9.1
1.5
9.1
1.5
9.1
1.5
9.1
1.5
9.1
1.5
9.1
1.5
9.1
N*
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
S***
RANGE
20.5- 20.9
2.8- 12.8
8.4- 9.8
0.0- 2.0
1901. -1903.
1342. -1567.
9.3- 9.6
9.0- 9.2
1240. -1690.
1330. -1920.
0.157-0.168
0.431-1.740
0.053-0.095
0.298-0.990
0.020-0.030
0.050-0.070
0.070-0.130
0.460-8.620
2. 700-3. OOQ
3.200-*****
= 2
MEDIAN
20.7
7.8
9.1
1.0
1902.
1455.
9.4
9.1
1465.
1625.
0.162
1.085
0.074
0.644
0.025
0.060
0.100
4.540
2.850
7.550
MAX
DEPTH
MANGE
(METERS)
0.0-
6.1-
0.0-
6.1-
0.0-
6.1-
0.0-
6.1-
0.0-
6.1-
0.0-
6.1-
0.0-
6.1-
0.0-
6.1-
0.0-
6.1-
0.0-
6.1-
0.0
15.5
0.0
15.5
0.0
15.5
0.0
15.5
0.0
15.5
0.0
15.5
0.0
15.5
0.0
15.5
0.0
15.5
0.0
15.5
S«»*
N« RANGE
4
2
4
2
4
2
4
2
4
2
4
2
4
2
4
2
4
2
4
2
14.8- 15. «
1.8- 12.9
11.4- 12.4
0.1- 5.2
1750. -1796.
1342. -1662.
9.0- 9.4
9.4- 9.4
920. -1370.
1380. -1390.
0.169-0.201
0.194-0.470
0.068-0.091
0.091-0.142
0.020-0.020
0.020-0.020
0.020-0.060
0.020-0.830
2.100-2.600
2.200-3.500
= 2
MEDIAN
15.6
7.3
11.9
2.6
1788.
1502.
9.3
9.4
1335.
1385.
0.197
0.332
0.089
0.116
0.020
0.020
0.020
0.425
2.450
2.850
MAX
DEPTH
RANGE
(METERS)
0.0-
6.1-
0.0-
6.1-
0.0-
6.1-
0.0-
6.1-
0.0-
6.1-
0.0-
6.1-
0.0-
6.1-
0.0-
6.1-
0.0-
6.1-
0.0-
6.1-
1.5
12.8
1.5
12.8
1.5
12.8
1.5
12.8
1.5
12.8
1.5
12.8 m
1.5
12.8
1.5
12.8
1.5
12.8
1.5
12.8
4.9- 5.0
4.9
2.1- 2.1
2.1
0.9- 0.9
0.9
N = NO. OF SAMPLES
MAXIMUM DEPTH SAMPLED AT EACH SITE
S = NO. OF SITES SAMPLED ON THIS DATE
-------
MEDICAL L«*E
STORET fOOE 5?0«
PHYSICAL AND CHEMICAL CHARACTERISTICS
( 10/24/75 )
PARAMETER
TEMPERATURE (DEC i
0.-1.5 M DEPTH
«AX OFPTH»»
DISSOLVED OXYGEN
0.-1.5 M DEPTH
MAX DEPTH**
N*
CFNT)
4
2
(MG/L)
4
?
CONDUCTIVITY (UMHOS)
0.-1.5 M DEPTH 4
MAX DEPTH** 2
PH (STANDARD UNITS)
0.-1.5 M OEPTH 4
MAX DEPTH** 2
TOTAL ALKALINITY
0.-1.5 M OEPTH
MAX DEPTH**
TOTAL P (MG/L)
0.-1.5 M DEPTH
MAX DEPTH**
DISSOLVED ORTHO P
0.-1.5 M DEPTH
MAX DEPTH**
N02+N03 (MG/L)
0.-1.5 M OEPTH
MAX DEPTH'*
AMMONIA (MG/L)
0.-1.5 M OEPTH
MAX DEPTH**
KJELDAHL N (MG/L)
0.-1.5 M OEPTH
MAX DEPTH'*
(MG/L)
4
1
4
2
(MG/L)
4
1
4
1
4
2
4
2
$tn>a
^ £• NGE
1?.A- 12.5
12.4- 12.5
5.4- 5.8
5.6- 5.9
1217. -1223.
1219. -1815.
*.2- 9.3
9.3- 9.3
1190. -1440.
1640. -1640.
0.263-0.305
0.273-0. ?74
0.161-0.168
0.159-0.159
0.020-0.020
0.020-0.020
0.020-0.210
0.1BO-0.220
2.600-2.900
2.400-2.600
= ?
••'ED I AN
12.4
12.4
5.5
5.7
1221.
1517.
9.3
9.3
13?5.
1640.
O.?70
0.273
0.1*4
0.159
0.0?0
O.P'O
0.105
0.200
2.600
2.500
MAX
DEPTH
li A AI /" C
H fltVibt
(«ETF
0.0-
7.9-
0.0-
7.9-
0.0-
7.9-
0.0-
7.9-
0.0-
7.9-
0.0-
7.9-
0.0-
7.9-
0.0-
7.9-
0.0-
7.9-
0.0-
7.9-
35)
1.5
8.5
1.5
8.5
1.5
8.5
1.5
8.5
1.5
7.9
1.5
8.5
1.5
7.9
1.5
7.9
1.5
8.5
1.5
8.5
SECCHI DISC
1.8- 1.8
1.6
« ^ = NO. OF SAMPLES
»» MAXIMUM DEPTH SAMPLED AT EACH SlTt
««« S = NO. OF SITES SAMPLED ON THIS DATE
-------
B. Biological Characteristics:
1. Phytoplankton -
Sampling
Date
06/03/75
07/23/75
09/11/75
10/24/75
Dominant
Genera
1. Chroomonas
2. Schroederia
3. Phormidium
4. Cryptomonas
Other genera
Total
1.
2.
3.
4.
5.
1.
2.
3.
Other genera
Total
Microcystis
Phormidium
Fragilaria
Cryptomonas
Pennate Diatom
Other genera
Total
Fragilaria
Anabaena
Microcystis
Other genera
Total
Algal
Units
per ml
769
678
271
226
1,944
1.
2.
3.
4.
5.
Nitzschia
Microcystis
Cryptomonas
Chroomonas
Aphanocapsa
2,267
599
385
342
257
384
4,234
1,560
1,147
551
229
229
277
3,993
2,032
290
145
2,467
-------
8
2. Chlorophyll a_ -
Sampling Station Chlorophyll a_
Date Number (yg/1)
06/03/75 01 1.5
02 1.9
07/23/75 01 14.3
02 36.5
09/11/75 01 29.0
02 16.0
10/24/75 01 17.1
02 15.1
-------
C. Limiting Nutrient Study:
1. Autoclaved, filtered, and nutrient spiked
a. 06/03/75
Spike (mg/1)
Control
0.05 P
0.05 P + 1.0 N
1.00 N
b. 09/11/75
Ortho P
Cone, (mq/1)
0.315
0.365
0.365
0.315
Spike (mg/1)
Ortho P
Cone, (mg/1)
Control
0.05 P
0.05 P + 1.0 N
1.00 N
c. 10/22/75
Spike (mg/1)
Control
0.05 P
0.05 P + 1.0 N
1.00 N
0.075
0.125
0.125
0.075
Ortho P
Cone, (mg/1)
0.105
0.155
0.155
0.105
Inorganic N
Cone, (mg/1)
0.380
0.380
1.380
1.380
Inorganic N
Cone, (mg/1)
0.135
0.135
1.135
1.135
Inorganic N
Cone, (mg/1)
0.275
0.275
1.275
1.275
Maximum Yield
(mg/1-dry wt.)
30.5
41.7
70.9
69.1
Maximum Yield
(mg/1-dry wt.)
9.0
8.6
31.4
22.0
Maximum Yield
(mg/1-dry wt.)
13.4
13.4
47.4
44.8
-------
10
2. Discussion -
The control yields of the assay alga, Selenastrum capri-
cornutum, indicate that the potential for primary production at
the times of sampling (06/03/75, 09/11/75, 10/22/75) in Medical
Lake was extremely high. In each sample, a significant increase
in growth over that of the control was produced by the addition
of nitrogen alone, indicating nitrogen limitation. The addition
of phosphorus alone stimulated growth beyond the control yield
only in the June assay. Spikes with nitrogen and phosphorus
simultaneously resulted in maximum growth yields in all three
samples.
The mean inorganic nitrogen to orthophosphorus ratios (N/P)
in sampled waters of 2/1 in June, 5/1 in July, 2/1 in September,
and 1/1 in October further suggest nitrogen limitation (a mean N/P
ratio of 14/1 or greater generally reflects phosphorus limitation).
-------
11
V. LITERATURE REVIEWED
Blau, Barbara. 1977. Personal communication (restoration of
Medical Lake). Washington Department of Ecology, Olympia,
Washington.
Fiedler, Glen H. 1977. Personal communication (restoration of
Medical Lake). Washington Department of Ecology. Olympia,
Washington.
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.
McConnell, J.B., Bortleson, G.C., and Innes, J.K. 1976. Data
on Selected Lakes in Washington, Part IV. Washington State
Department of Ecology/U.S. Geological Survey, Water Supply
Bulletin 42.
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.
Wolcott, E. E. 1965. Lakes of Washington, Volume II. Washington
Division of Water Resources, Water Supply Bulletin, Volume 14.
-------
12
VI. APPENDICES
APPENDIX A
CONVERSION FACTORS
-------
CONVERSION FACTORS
Hectares x 2.471 = acres
Kilometers x 0.6214 = miles
Meters x 3.281 = feet
-4
Cubic meters x 8.107 x 10 = acre/feet
Square kilometers x 0.3861 - square miles
Cubic motors/sec x 35.315 = cubic feet/sec
Centimeters x 0.3937 = inches
Kilograms x 2.205 - pounds
Kilograms/square kilometer x 5.711 •-- Ibs/squarc mile
-------
APPENDIX B
PHYSICAL AND CHEMICAL DATA
-------
5TO°ET °ETf?IEV4L
KiATL trUTOO°HlCATIO'M
VEGAS
00010
DATE
TO
75/06/03
75/07/23
75/09/11
75/10/24
TIME OEPTi- ,
DAY FEET
14
14
14
09
09
09
09
15
15
15
15
10
10
10
10
55
55
55
40
40
40
40
40
40
40
40
15
15
15
15
0000
000=;
oo?o
0000
0010
0015
00^0
0000
0005
0015
0020
0000
0005
0015
00?R
-------
ogTPIE\/Al. OfiTF 76/11/16
NATL ffUTPO
EPA-t.AS VEGAS
53080?
47 33 58.0 117 41 22.0 3
"EDICAL LAKE
53063 WASHINGTON
11EPALES ?11120?
0034 FFET DEPTH CLASS 00
00010
00300
OATF
FOO-*
TO
75/06/03
75/07/23
75/09/11
75/10/?4
TI>*F OEPT'J 4
OF
HAY FFPT
15
15
15
15
09
09
09
09
09
16
16
16
16
10
10
10
10
15
15
15
15
20
20
20
20
20
05
05
05
05
40
40
40
40
0000
0005
001°
0030
0000
0011
001^
0040
0051
000"
0005
OOl1^
0042
0000
000^
0015
0026
JATEO
TEMP
CENT
16.3
15.7
11.9
6.9
20.5
20.4
12.9
2.9
2.8
15.8
15.8
14.5
1.8
12.5
12.5
12.5
12.5
on
MG/L
7.?
7.2
6.4
0.6
9.8
o.n
0.0
0.0
0.0
12.4
12.2
6.0
0.1
5.8
5.6
5.6
5.8
00077
TPANS0
cECChl
INCHES
19?
84
36
72
00094
CNOIJCTVY
FIELD
MICROMHO
14?7
1406
1261
1153
1903
1828
1597
1323
1342
1796
1795
1656
1342
1223
1223
1223
1219
00400
PH
su
00410
T ALK
CAC03
MG/L
00610 00*25
NH3-N TOT KJEL
TOTAL N
MG/L
00630 00671
NO?f,N03 PHrtS-DIS
N-TOTftL OtfTHO
MG/L Mfi/L P
14?7
1406
1261
1153
1903
1828
1597
1323
1342
1796
1795
1656
1342
1223
1223
1223
1219
9.?0
9.20
9.20
9.20
9.60
9.50
9.25
9.?0
9.05
9.40
9.40
9.00
9.40
9.35
9.35
9.30
9.35
1510
1400
1430
1320
1240
1340
1410
1260
1920
1370
1300
1250
1380
1410
1440
1350
1640
0.350
0.340
0.600
0.730
0.070
0.060
0.140
3.470
8.620
0.020K
0.020
0.830
0.210
0.190
0.210
0.2?0
P.700
2.700
3.300
3.400
2.700
?.700
3.600
6.700
11.900
2.400
2.500
3.700
3.500
?.600
2.900
2.800
2.600
0.350
0.340
O.?30
0.120
0.030
0.030
0.050
0.060
0.070
0.020K
0.020K
0.020K
0.020K
0.020K
0.020K
0.020K
0.020K
0.315
0.315
0.380
0.437
0.053
0.068
0.213
0.720
0.990
0.089
0.091
0.359
0.14?
0.161
0.163
0.163
0.159
DiTF TIME DE^TH PHOS-TOT
FRO" OF
TO DAY FEET MG/L P
75/06/03
75/07/23
75/09/11
75/10/24
15
15
15
15
09
09
09
09
09
16
16
16
.16
10
10
10
10
15
15
15
15
20
20
20
20
20
05
05
05
05
40
40
40
40
0000
0005
0018
0030
0000
0010
OOIS
0040
0051
0000
0005
001 =
004?
0000
0005
0015
0026
0
0
0
0
0
0
0
1
1
0
0
0
n
0
0
0
n
.359
.364
.4RQ
.570
.157
.199
.479
.220
.740
.201
.197
.640
.470
.?63
.305
.276
.274
32217
CHLRPHYL
A
UG/L
1 .9
36.5
16.0
15.1
00031
TMCOT !_T
K VALUE KNOWN TO BE LESS
THAN INDICATED
-------
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.
-------
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 LAKF
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
2R8.000
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
0.002
0.007
0.166
0.038
0.009
0.006
0.009
0.022
-------
PERCENT OF LAKES WITH HIGHER VALUES (NUMBER OF LAKES WITH HIGHER VALUES)
LAKE
CODE LAKE
5301 AMERICAN LAKE
5302 BANKS LAKE
5303 CHELAN LAKE
5304 DIAMOND LAKE
5305 GREF.N LAKE
5306 KEECHELUS LAKE
5307 MAYFIELD LAKE
5309 MEDICAL LAKE
5309 MOSES LAKE
5310 OZETTE LAKE
5311 SAMMAMISH LAKE
5312 WHATCOM LAKE
5313 LOWER GRANITE RESERVOIR
MEDIAN
TOTAL P
29 (
42 1
100 1
6? 1
29 1
92 1
62 1
0 1
8 I
75 i
50 i
83
17
3)
: 5)
: 12)
: 7)
! 3)
: ii)
! 7)
! 0)
1 1)
: 9)
( 6)
( 10)
( 2)
MEDIAN
INORG N
50 (
100 <
67 (
75 1
83 1
92 1
58 1
8 1
29 1
42 1
17 i
0 <
29
6)
I 12)
! 8)
: 9)
: 10)
: ID
[ 7)
: i)
: 3)
! 5)
( 2)
( 0)
( 3)
500-
MEAN SEC
67 1
58 1
100 1
75 1
17 1
92 1
33 1
42 1
0 I
25 i
50 <
83
8
: 8>
[ 7)
[ 12)
I 9)
[ 2)
I 11)
[ 4)
! 5)
I 0)
( 3)
( 6)
( 10)
( 1)
MEAN
CHLORA
50 (
25 (
100 (
17 1
75 (
83 1
58 1
8 1
0 I
92 (
33 i
67 i
42 i
: 6)
: 3>
: 12)
: 2)
I 9)
: 10)
:• 7)
! 1)
[ 0)
! 11)
t 4)
( 8)
( 5)
15-
MIN DO
4 1
46 I
100 i
33 i
62
75 i
62 i
* '
21
87
21
46
87
[ f 0)
( 5)
( 12)
[ 4)
( 7)
t 9)
( 7)
( 0)
( 2)
( 10)
( 2)
( 5)
( 10)
MEDIAN
DISS ORTMO
58 (
71 (
92 (
25 <
46 I
100 1
71 (
0 1
8 (
33 1
83 I
46 1
17 i
7)
; ft)
: in
: 3)
[ 5)
: i?)
1 *A %
1 f* /
: o)
! 1)
: 4)
[ i")
t 5)
t 2)
------- |