U.S. ENVIRONMENTAL PROTECTION AGENCY
NATIONAL EUTROPHICATION SURVEY
WORKING PAPER SERIES
REPORT
ON
UPPER PAHRANAGAT U\KE
LINCOLN COUNTY
NEVADA
EPA REGION IX
WORKING PAPER No, 812
CORVALLIS ENVIRONMENTAL RESEARCH LABORATORY - CORVALLIS, OREGON
and
ENVIRONMENTAL MONITORING & SUPPORT LABORATORY - LAS VEGAS, NEVADA
-------
REPORT
ON
UPPER PAHRANAGAT LAKE
LINCOLN COUNTY
NEVADA
EPA REGION IX
WORKING PAPER No, 812
WITH THE COOPERATION OF THE
NEVADA ENVIRONMENTAL PROTECTION SERVICE
AND THE
NEVADA NATIONAL GUARD
SEPTEMBER, 1977
-------
REPORT ON UPPER PAHRANAGAT LAKE
LINCOLN COUNTY, NEVADA
EPA REGION IX
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. 812
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
September 1977
-------
CONTENTS
Foreword i i
List of Nevada Study Lakes 1v1'
Sections
I. Conclusions 1
II. Lake and Drainage Basin Characteristics 3
III. Lake Water Quality Summary 5
IV. Nutrient Loadings 9
V. Literature Reviewed 14
VI. Appendices 15
-------
11
FOREWORD
The National Eutrophication Survey was Initiated in 1972 in
response to an Administration commitment to investigate the nation-
wide threat of accelerated eutrophication to freshwater lakes and
reservoirs.
OBJECTIVES
The Survey was designed to develop, in conjunction with state
environmental agencies, information on nutrient sources, concen-
trations, and impact on selected freshwater lakes as a basis for
formulating comprehensive and coordinated national, regional, and
state management practices relating to point source discharge
reduction and nonpoint source pollution abatement in lake water-
sheds.
ANALYTIC APPROACH
The mathematical and statistical procedures selected for the
Survey's eutrophication analysis are based on related concepts
that:
a. A generalized representation or model relating
sources, concentrations, and impacts can be
constructed.
b. By applying measurements of relevant parameters
associated with lake degradation, the generalized
model can be transformed into an operational
representation of a lake, its drainage basin, and
related nutrients.
c. With such a transformation, an assessment of the
potential for eutrophication control can be made.
LAKE ANALYSIS
In this report, the first stage of evaluation of lake and
watershed data collected from the study lake and its drainage
basin is documented. The report is formatted to provide state
environmental agencies with specific information for basin
planning [§303(e)], water quality criteria/standards review
[§303(cj], clean lakes [§314(a,b)J, and water quality monitoring
[§106 and §305(b)] activities mandated by the Federal Water
Pollution Control Act Amendments of 1972.
-------
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 refinement of nutrient water quality criteria for
the Nation's freshwater lakes. Likewise, multivariate evaluations
for the relationships between land use, nutrient export, and
trophic condition, by lake class or use, are being developed
to assist in the formulation of planning guidelines and policies
by the U.S. Environmental Protection Agency and to augment
plans implementation by the States.
ACKNOWLEDGMENTS
The staff of the National Eutrophication Survey (Office
of Research and Development, U.S. Environmental Protection
Agency) expresses sincere appreciation to the Nevada State
Environmental Protection Service for professional involvement,
to the Nevada National Guard for conducting the tributary
sampling phase of the Survey, and to those Nevada wastewater
treatment plant operators who provided effluent samples and
flow data.
The staff of the Department of Conservation and Natural
Resources, Division of Environmental Protection, State Environmental
Protection Service provided invaluable lake documentation
and counsel during the Survey, reviewed the preliminary reports
and provided critiques most useful in the preparation of this
Working Paper Series.
Major General Floyd L. Edsall, the Adjutant General of
Nevada, and Project Officer Major Harold E. Roberts, who directed
the volunteer efforts of the Nevada National Guardsmen, are
also gratefully acknowledged for their assistance to the Survey.
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IV
NATIONAL EUTROPHICATION SURVEY
STUDY LAKES
STATE OF NEVADA
LAKE NAME
Lake Mead
Lahontan Reservoir
Rye Patch Reservoir
Lake Tahoe
Topaz Reservoir
Upper Pahranagat Lake
Washoe Lake
Wildhorse Reservoir
Wilson Reservoir
Walker Lake
COUNTY
Clark (Mohave in Arizona)
Lyon, Churchill
Pershing
Washoe, Carson City,
Douglas (Placer,
El Dorado in CA)
Douglas (Mono in CA)
Lincoln
Washoe
Elko
Elko
Mineral
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UPPER PAHRANAGAT LAKE
® Tributary Sampling Site
X Lake Sampling Site
° __] ?Km.
o 4 i Mi.
Scale /
-------
UPPER PAHRANAGAT LAKE
$) tributary Vt'iijil IMM Site
t
10 Mi.
SCdlf
/ s
/ <
Mtip Loc.itioi
• Alomo
UPPfH PAHRANAGAT
\tttrt
-------
REPORT ON UPPER PAHRANAGAT LAKE, NEVADA
STORE! NO. 3207
I. CONCLUSIONS
A. Trophic Condition:*
Survey data indicate that Upper Pahranagat Lake is eutrophic,
i.e., nutrient rich and highly productive. Whether such nutrient
enrichment is to be considered beneficial or deleterious is
determined by its actual or potential impact upon designated
beneficial water uses of the lake.
Potential for primary production as measured by the algal
assay control yield was low. Secchi disc visibility was quite
low. Of the 10 Nevada lakes sampled in 1975, 3 had higher
median total phosphorus values (0.173 mg/1), 5 had higher median
inorganic nitrogen levels (0.125 mg/1), and 6 had higher median
orthophosphorus values (0.026 mg/1) than Upper Pahranagat Lake.
Survey limnologists reported emergent vegetation accumu-
lation along half of the shoreline on their visits to the lake.
B. Rate-Limiting Nutrient:
Algal assay results indicate that Upper Pahranagat Lake
was limited by available phosphorus during the sample collection
time (05/06/75). Lake data suggest primary limitation by ni-
trogen on the three sampling occasions.
*See Appendix E.
-------
C. Nutrient Controllability:
1. Point sources -
There were no known point sources impacting Upper Pahranagat
Lake during the sampling year.
n
The present phosphorus loading of 1.30 g P/m /yr is over
three times that proposed by Vollenweider (1975) as "eutrophic"
for a lake of such volume and hydraulic retention time. The
Nevada Environmental Protection Services (1976) reports that
the primary problem of the lake, that of high phosphorus levels,
is mainly attributable to agricultural runoff and natural non-
point contributions.
2. Nonpoint sources -
The White River (B-l) contributed 53.8% of the total phos-
phorus load to Upper Pahranagat Lake during the sampling year;
ungaged tributaries and immediate drainage contributed an
estimated 15.0%.
Upper Pahranagat Lake is in the Pahranagat National Wild-
life Refuge. Considerable numbers of ducks and geese utilize
the reservoir. On the basis of numbers provided by the U.S.
Fish and Game Department and certain assumptions (see page 10),
it is estimated that wildfowl contributed 380 kg of phosphorus
(30.0% of the total load) to the lake during the sampling year.
-------
II. LAKE AND DRAINAGE BASIN CHARACTERISTICS
Lake and drainage basin characteristics are itemized below.
Lake morphometry data were provided by James B. Hilliams, Jr.
(personal communication). Tributary flow data were provided by the
Nevada District Office of the U.S. Geological Survey (USGS). Out-
let drainage area includes the lake surface area. The difference
between inflow and outflow to the lake can be attributed to high
evaporation in the area in irrigational water uses. Mean hydraulic
retention time was obtained by dividing the lake volume by the
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:
1. Surface area: 0.97 km2.
2. Mean depth: 0.6 meters.
3. Maximum depth: 1.5 meters.
4. Volume: 0.592 x 10& m3.
5. Mean hydraulic retention time: 57 days.
-------
B. Tributary and Outlet:
(See Appendix B for flow data)
1. Tributaries -
Drainage Mean Flow
Name area (km2) (m3/sec)
B-l White River 6,765.1 0.22
Minor tributaries and
immediate drainage - 78.3 0.04
Total 6,843.4 0.26
2. Outlet - A-l White River 6,845.4 0.12
C. Precipitation:
1. Year of sampling: 21.2 cm.
2. Mean annual: 22.1 cm.
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III. LAKE WATER QUALITY SUMMARY
Upper Pahranagat 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 col-
lected from three stations (Station 01 was sampled only once) on the
lake and from one or more depths at each station (see maps, pages
v,vi)- During each visit, depth-integrated samples were collected
from each station for phytoplankton identification and enumeration*
During the first visit, an 18.9-liter depth-integrated sample was
composited for algal assays. Maximum depths sampled were 1.5 meters
at Station 01, 2.1 meters at Station 02, and 2.7 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 a, determinations are included in III-B. Results of the limiting
nutrient study are presented in III-C.
-------
')-c
JANG-.
)
•*iX
= •> C>EJT->
3ANGF
"hOTAN (METE-S)
( 8/21/75 )
s»«* = ,? DEPTH
RANG?
*ANGt MEDIAN ("ETERS1
"J»
( 11/21/75 )
MAX
S*
12.5
8.?
8.1
t "7 c
I 1 5.
76n.
6.3
**»*»
0.0-
1 .5-
0.0-
2.1-
0 . 0 —
1.5-
0.0-
»50»-»
1 .5
2.7
1.5
2.7
1.5
2.7
0.0
*»»*
3
2
3
2
0
0
3
?
18.0- 20.0
18.0- eO.O
b.4- 7.4
6.4- 7.4
.....-.*..*
b.6- 8.7
8.7- 8.7
20.0
19.0
7.2
6.9
8.7
8.7
0.0-
0.0-
0.0-
0.0-
*o**-.
0.0-
0.0-
0.9
0.9
0.9
0.9
*oo*
0.9
0.9
2
?
2
2
2
2
2
?
9.0- 9.0
9.0- 9.0
10.8- 11.4
10.8- 11.4
922.- 979.
922.- 979.
8.3- 8.5
8.3- 8.5
9.0
9.0
11.1
11.1
950.
950.
8.4
8.4
0.0- 0.0
0.0- 0.0
0.0- 0.0
0.0- 0.0
On. An
• 0~ U • U
0.0- 0.0
0.0- 0.0
0.0- 0.0
TOTAL ALKALINITY (Mfi/L)
O.-l.S w DEPTH
WAX DEPTH**
TOTAL P (MG/L>
O.-l.S M DEPTH
MAX DEpTH*»
5
?-
5
?
605.- 680.
S80.- 660.
0.029-0.226
0.030-0.453
620.
620.
O.OH
0.241
0.0-
2.1-
n.o-
2.1-
1.5
2.7
1.5
2.7
3
?
3
2
550.- 605.
550.- 605.
0.162-0.309
0.275-0.309
595.
578.
0.275
0.292
0.0-
0.0-
0.0-
0.0-
0.9
0.9
0.9
0.9
2
2
2
2
390.- 400.
390.- 400.
0.184-0.268
0.184-0.268
395.
395.
O.?2b
0.226
0.0- 0.0
0.0- 0.0
o.o- o.o
0.0- 0.0
DISSOLVED ORTHO P (MG/L)
O.-l.S M DEPTH
MAX DEPTH**
N02»NO3 (MG/L)
O.-l.S M DEPTH
MA< DEPTH**
AMMONIA (MG/L)
O.-l.S M DEPTH
«AX DEPTH**
KJELDAHL N (MG/L)
O.-l.S M DEPTH
MAX DEPTH**
5
?
B
2
5
2
5
2
0. 012-0. 20«
0.008-0.417
0.060-0.100
0.070-0.090
0.050-0.070
0.060-0.140
0.700-0.900
0.700-0.700
0.0?1
0.212
0.070
0.080
0.070
0.100
0.700
0.700
0.0-
2.1-
0.0-
?.l-
0.0-
2.1-
0.0-
2.1-
1.5
2.7
1.5
2.7
1.5
2.7
1.5
2.7
3
2
1
?
3
2
3
?
0.030-0.044
0.036-0.044
0.020-0.020
0.020-0.020
O.OPO-0.050
0.020-0.050
1 .?00-2.200
1 .200-2.200
0.036
0.040
0.020
0.020
0.030
0.035
1.300
1.700
0.0-
0.0-
0.0-
0.0-
0.0-
0.0-
0.0-
0.0-
0.9
0.9
0.9
0.9
0.9
0.9
0.9
0.9
2
2
2
2
2
2
2
2
0.017-0.019
0.017-0.019
0.020-0.030
0.020-0.030
0.030-0.040
0.030-0.040
0.500-1.200
0.500-1.200
0.018
0.018
0.025
0.025
0.035
0.035
0.850
0.850
0.0- 0.0
0.0- 0.0
0.0- 0.0
0.0- 0.0
0.0- 0.0
0.0- 0.0
0.0- 0.0
0.0- 0.0
SECCHI DISC
0.9- 1.5
1.2
0.1- 0.1
0.1
* M = NO. (IF SAMD(_tc
** MAXIMUM DEPTH SAMPLED AT EACH «ITE
*»* «, = NO. OF SITES SAMPLED 0>M Tnl^ DATE
-------
B. Biological Characteristics:
1. Phytoplankton -
Sampling
Date
05/06/75
08/21/75
11/21/75
Dominant
Genera
1, Chroomonas?
2. Schroederia
3. Cryptomonas
4. Ankistrodesmus
5. QuadriguTa"
Other genera
Total
1. Merismopedia
2. Euglena
3. Cyclotella
4. Pennate diatom
5. Phacus
Other genera
Total
1. Pennate diatom
2. Navicula
3. Chroomonas?
4. Cylindrotheca
5. Nitzschia
Other genera
Total
Algal
Units
Per ml
425
196
163
65
65
34
948
37,834
946
883
568
252
436
2,674
-------
8
2. Chlorophyll a^ - Not available for this lake.
C. Limiting Nutrient Study:
1. Autoclaved, filtered, and nutrient spiked - 05/06/75
Ortho P Inorganic N Maximum Yield
Spike (mg/1) Cone, (mg/1) Cone, (mg/1) (mg/l-dry wt.)
Control
0.05 P
0.05 P + 1.0 N
1.00 N
0.007
0.057
0.057
0.007
0.215
0.215
1.215
1.215
0.2
8.8
18.3
0.1
2. Discussion -
The control yield of the assay alga, Selenastrum capri-
cornutum*, indicates that the potential for primary productivity
in Upper Pahranagat Lake was low during the sample collection
time (05/06/75). The increased growth of the test alga over
the control yield in response to the addition of phosphorus as
well as the lack of response to the addition of nitrogen alone
indicates phosphorus limitation. Maximum yield was achieved
with the simultaneous addition of both phosphorus and nitrogen.
The mean inorganic nitrogen to orthophosphorus ratios
(N/P) in the lake data were 3/1 or less on the three sampling
dates suggesting primary limitation by nitrogen (a mean N/P
ratio of 14/1 or greater generally reflects phosphorus limi-
tation).
*For further information regarding the algal assay test procedure
and selection of test organisms, see U.S. EPA (1971).
-------
IV. NUTRIENT LOADINGS
(See Appendix D for data)
For the determination of nutrient loadings, the Nevada National
Guard collected monthly near-surface grab samples from each of the
tributary sites indicated on the maps (pages v,vi), except for the
high runoff month of July when two samples were collected. Sampling
was begun in November 1974, and was completed in October 1975.
Through an interagency agreement, stream flow estimates for the
year of sampling and a "normalized" or average year were provided by
the Nevada District Office of the USGS for the tributary sites nearest
the lake.
In this report, nutrient loads for sampled tributaries were
determined by using a modification of a USGS computer program for
calculating stream loadings. Nutrient loads indicated for tributaries
are those measured minus known point source loads, if any.
Nutrient loadings for unsampled "minor tributaries and immediate
drainage" ("ZZ" of USGS) were estimated by using the mean annual con-
centrations in the White River at Station B-l and mean annual ZZ flow.
Estimates of nutrient contributions by wild ducks and geese were
based upon information on the number of waterfowl in the Pahranagat
National Wildlife Refuge provided by the U.S. Fish and Wildlife
Service (Himmel, 1976). The following number of wild ducks and geese
assumed to be using Upper Pahranagat Lake are based on one-half of
-------
10
the refugee total:
Residence Time
Number (months)
Summer resident ducks 700 5
Summer resident geese 22 8
Migratory ducks 2,700 7
Migratory geese 85 4
In calculating the nutrient loads the following assumptions
were made:
1. Each wild duck contributes 0.45 kg total nitrogen and
0.20 kg phosphorus per year (Paloumpis and Starrett 1960).
2. Each wild goose contributes the same amount as one
duck since geese typically feed in fields away from the
lake several hours each day.
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11
A. Waste Sources:
1. Known municipal - None
2. Known industrial - None
B. Annual Total Phosphorus Loading - Average Year:
1. Inputs -
% of
Source kg P/yr total
a. Tributaries (nonpoint load) -
B-l White River 680 53.8
b. Minor tributaries and immediate
drainage (nonpoint load) - 190 15.0
c. Known municipal STP's - None
d. Septic tanks - None known
e. Known industrial - None
f. Wild ducks and geese - 380 30.0
g. Direct precipitation* - 15 1.2
Total 1,265 100.0%
2. Outputs - A-l White River 359
3. Net annual P accumulation - 905
*Estimated (See NES Working Paper No. 175).
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12
C. Annual Total Nitrogen Loading - Average Year:
1. Inputs -
% of
Source kg N/yr total
a. Tributaries (nonpoint load) -
B-l White River 7,620 67.5
i
b. Minor tributaries and immediate
drainage (nonpoint load) - 1,770 15.7
c. Known municipal STP's - None
d. Septic tanks - None known
e. Known industrial - None
f. Wild ducks and geese - 860 7.6
g. Direct precipitation* - 1,045 9.2
Total 11,295 100.0%
2. Outputs - A-l White River 5,525
3. Net annual N accumulation - 5,770
*Estimated (See NES Working Paper No. 175).
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13
D. Mean Annual Nonpoint Nutrient Export by Subdrainage Area:
Tributary kg P/km2/yr kg N/km /yr
White River <1 1
E. Yearly Loadings:
In the following table, the existing phosphorus annual
loading is compared to the relationship proposed by Vollenweider
(1975). Essentially, his "eutrophic" loading is that at which
the receiving waters would become eutrophic or remain eutrophic;
his "oligotrophic" loading is that which would result in the
receiving water remaining oligotrophic or becoming oligotrophic
if morphometry permitted. A "mesotrophic" loading would be
considered one between "eutrophic" and "oligotrophic".
Note that Vollenweider's model may not apply to lakes with
short hydraulic retention times or in which light penetration is
severely restricted by high concentrations of suspended solids
in the surface waters.
Total Yearly
Phosphorus Loading
(g/m?/yr)
Estimated loading for Upper Pahranagat Lake 1.30
Vollenweider's "eutrophic" loading 0.38
Vollenweider's "oligotrophic" loading 0.19
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14
V. LITERATURE REVIEWED
Himmel, Cliff. 1976. Personal communication (ducks). U.S. Fish
and Wildlife Service, Las Vegas, Nevada.
Nevada Environmental Protection Services. 1976. Water Quality
Management Plan, Colorado River Basin and Colorado River Main Stem
Basin. Department of Human Resources, Carson City, Nevada.
Paloumpis, A. A. and W. E. Starett. 1960. An Ecological Study of
Benthic Organisms in Three Illinois River Flood Plain Lakes.
Amer. Midi. Natl. 64(2):406-435.
U.S. Environmental Protection Agency. 1971. Algal Assay
Procedure Bottle Test. National Eutrophication Research
Program, Corvallis, Oregon.
U.S. Environmental Protection Agency. 1975. National Eutrophica-
tion Survey Methods 1973-1976. Working Paper No. 175. National
Environmental Research Center, Las Vegas, Nevada, and Pacific
Northwest Environmental Research Laboratory, Corvallis, Oregon.
Vollenweider, R.A. 1975. Input-Output Models With Special
Reference to the Phosphorus Loading Concept in Limnology.
Schweiz. Z. Hydrol. 37:53-84.
Williams, James B., Jr. 1974. Personal communication (lake mor-
phometry). Department of Human Resources, Carson City, Nevada.
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15
VI. APPENDICES
APPENDIX A
CONVERSION FACTORS
-------
CONVERSION FACTORS
Hectares x 2.471 = acres
Kilometers x 0.6214 = miles
Meters x 3.201 = feet
Cubic meters x 8.107 x 10" = acre/feet
Square kilometers x 0.3861 - square miles
Cubic rneters/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
TRIBUTARY FLOW DATA
-------
TRIBUTARY FLOW INFORMATION FOP NEVADA
LAKE CODE 3?07 UPPER PAHRANAGAT LAKE
TOTAL OPAINAGE AREA OF LAKF(SQ KM) 6845.4
1/21/77
SU8-DSAINAGE
TRIBUTARY AREA(SQ KM)
JAN
FE&
3207A1
3207R1
3207ZZ
6845.4
6765.1
79.3
0.028 0.017
0.340 0.396
0.085 0.085
0.017
0.538
0.079
APR
0.227
0.481
0.241
MAY
0.283
0.09*
O.OOH
NORMALIZED FLOwS(CMS)
JUN JUL AUG
0.340
0.068
0.0
0.227
0.076
0.0
0.113
0.184
0.0
SEP
o.oes
0.062
0.0
OCT
0.085
0.062
0.0
NOV
0.028
0.108
0.0
DEC
MEAN
0.028 0.124
0.232 0.219
0.040 0.044
SUMMARY
TOTAL DRAINAGE AREA OF LAKE =
SUM OF SUB-DRAINAGE AREAS =
6845.4
6844.3
TOTAL FLOW IN
TOTAL FLOW OUT
3.18
1.4ft
MEAN MONTHLY FLO*S AND DAILY
TRIBUTARY MONTH YEAR MEAN FLO*
3207A1
DAV
FLO* DAY
FLO* DAY
FLOW
3207H1
11
12
1
2
3
4
5
6
7
8
9
10
11
12
1
2
3
4
5
6
7
8
9
10
74
74
75
75
75
75
75
75
75
75
75
75
74
74
75
75
75
75
75
75
75
75
75
75
0.071
0.008
0.008
0.008
0.113
0.142
0.156
0.113
0.057
0.042
0.071
0.003
0.368
0.453
0.510
0.481
0.396
0.113
0.037
0.042
0.008
0.003
0.014
0.008
?n
23
2?
7
1?
21
is
7
n
17
21
2ft
21
2?
7
1?
21
is
7
11
17
21
0.079
0.008
0.011
0.006
0.113
0.113
0.170
0.057
0.057
0.071
0.0
0.396
0.481
0.566
0.481
0.453
0.085
0.028
0.008
0.003
0.014
0.008
Ifl
0.042
0.008
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APPENDIX C
PHYSICAL AND CHEMICAL DATA
-------
STORET RETRIEVAL DATE 77/01/26
MAIL EUTRQPHICATIO\ SURVEY
FPA-LAS VEGAS
/TYPA/AMBNT/LAKE
DATE TIME DEPTH *ATER
FROM OF
TO DAY FEET
75/05/06 15 10 0000
15 10 0005
320701
37 18 33.0 115 07 48.0 3
UPPER PAHRANAGAT LAKE
32017 NEVADA
110191
11EPALES 04001002
0005 FEET DEPTH CLASS 00
)010
-ER
;MP
:NT
13.8
13.5
00300
DO
MG/L
8.2
00077
THANSP
SECCMl
INCHES
60
00094
CNDUCTVY
FIELD
MICROMHO
840
800
00400
PH
Sll
6.30
00410
T ALK
CAC03
MG/L
615
00610
NH3-N
TOTAL
MG/L
0.050
00625
TOT KJEL
N
MG/L
0.700
00630
N02S.N03
N-TOTAL
MG/L
0.100
00671
Pnns-DIS
OWTHO
MG/L P
0.012
_ 00665
DATE TIME DEPTH PHOS-TOT
FROM OF
TO DAY FEET MG/L P
75/05/06 15 10 0000
0.029
32217
CHLRPHYL
A
UG/L
00031
INCDT LT
RFMNING
PFKCENT
-------
ST03ET RETRIEVAL DATE 77/01/26
NATL EUTROPHICATIO.N SURVEY
EPA-LAS VEGAS
/TYPA/AM8NT/LAKE
DATE
FSOM
TO
75/05/06
75/08/21
75/11/21
DATE
FROM
TO
75/05/06
75/08/21
75/11/21
TIME DEPTH
OF
DAY FEET
15 40 0000
15 40 0003
15 40 0007
16 30 0000
12 00 0000
TIME DEPTH
OF
DAY FEET
15 40 0000
15 40 0003
15 40 0007
16 30 0000
12 00 0000
00010
WATER
TEMP
CENT
13.5
12.5
11.5
20.0
9.0
00665
PHOS-TOT
MG/L P
0.226
0.031
0.030
0.309
0.268
00300
DO
MG/L
7.8
7.8
7.6
7.4
11.4
32217
CHLHPHYL
A
UG/L
00077
TRANSP
SECCHI
INCHES
47
2
00031
INCDT LT
RFMNING
PEHCENT
00094
CNDUCTVY
FIELD
MICROMHO
770
760
750
979
320702
37 18 02.0 115 07 35.0 3
UPPER PAHRANAGAT LAKE
32017 NEVADA
110191
11EPALES 04001002
0006 FEET DEPTH CLASS 00
00400
PH
SU
8.70
8.50
00410
T ALK
CAC03
MG/L
680
645
660
550
400
00610
NH3-N
TOTAL
MG/L
0.070
0.060
0.060
0.050
0.030
00625
TOT KJEL
M
MG/L
0.900
0.700
0.700
2.300
0.500
00630
N02&N03
N-TOTAL
Mfi/L
0.060
0.060
0.070
0.020K
0.030
00671
PHOS-OIS
OtfTnO
Mfi/L P
0.208
0.013
0.008
0.044
0.017
K VALUE KNOWN TO BE LESS
THAN INDICATED
-------
ST03ET RETRIEVAL DATE 77/01/26
NATL EUTHOPHICATION SUPVEY
EPA-LAS VEGAS
/TYPA/AM8NT/LAKE
DATE TIME DEPTH
FROM OF
TO DAY FEET
75/05/06
16 25
16 25
0000
0005
16 35 0009
0000
0003
75/11/21 10 30 0000
75/08/21
16 53
16 53
DATE TIME OEPT*
FROM OF
TO DAY FEET
75/05/06 16 25 0000
16 25 0005
16 25 0009
75/08/21 16 53 0000
16 53 0003
75/11/21 10 30 0000
320703
37 17 33.0 115 07 20.0 3
UPPER PAHRANAGAT LAKE
32017 NEVADA
110191
11EPALES
04001002
0010 FEET DEPTH CLASS
0010
TER
EMP
ENT
13.8
12.7
12.5
20.0
18.0
9.0
0665
S-TOT
/L P
0.030
0.037
0.453
0.162
0.275
0.184
00300
DO
HG/L
8.2
8.4
a. 6
7.2
6.4
10.8
32217
CHLHPHYL
A
UG/L
00077 00094
TPAMSP CNOUCTVY
CECCHI FIELD
INCHES MICROMHO
36 780
760
760
<-,
922
00031
INCDT LT
PF.MNING
PFRCENT
00400 00410
PH T ALK
CAC03
SU MG/L
605
620
580
8.65 595
8.70 605
8.30 390
00610
NH3-N
TOTAL
MG/L
0.070
0.070
0.140
0.030
0.020
0.040
00
00625
TOT KJEL
N
MG/L
0.700
0.700
0.700
1.300
1.200
1.200
00630 00671
N028.N03 PHOS-DIS
N-TOTAL OeT-iO
MG/L *r,/L P
0.070
0.080
0.090
0.020K
0.020K
0.020
0.021
0.030
0.417
0.030
0.036
0.019
K VALUE KNOWN TO BE LESS
THAN INDICATED
-------
APPENDIX D
TRIBUTARY AND WASTEWATER
TREATMENT PLANT DATA
-------
' • •' /st
/ I v .-• ft / i ' -'
32C7A1
37 37 ->0.0 113 07 IS.n 4
White River
3? 7.S flLAfU) SF
-"AnKAfJAGAT LA«t~ ll'Tl
OnT H*0 6.^ "
7^/0 1/\'f> 10 00
7 H X 0 4 X 2 1 09 0 r>
\ •
N-T-
h 3 o n ;
MJI Tor
TiL
KJtL
•n>/L Mj/L
ij
i\
(j
ii
u
fi
U
(J
()
(I
')
1,
.041
.041
,G?i»
.010
.on-.
.010
.041.1
.030
,07S
.OOS
. 160
.00^
0
1
1
1
0
1
0
0
I
?
1
I
,-*oo
. 300
. -JOG
.400
,e>00
.200
.H5 J
.•-HOs-TOT
rO
L
.
.
.
.
.
.
.
.
.
.
.
.
"
010
ul 0
ft to
U20
Cl-7
010
02 =
U?'!^
01S
030
l>-b
020
-------
/T t f
75/0 //07
75/10/21
15
14
) 1
11
11
4'!
10 0 'I
10 30
75/03/1? 10 IS
09 15
O'l
01!
M-TcTAL
•-ILVL
11.005
0 . 0 6'.)
0,
J 1 .
0000
115 0-1 15.0 »
A|_Ar*il ST
H <> 1 *
SE. OK AI
04001004
CLASS 00
3.5
'J
•1
I
1
0
1
I
1
0
1
3
1
. 7 ;, o
.MOO
. 0 0 f i
.250
.100
. 350
.350
.300
.8^5
.400
.400
. 5 C">
0
0
0
0
0
0
0
0
0
0
u
0
•
•
•
•
•
•
•
•
•
•
•
•
030
1)15
t)4o
045
030
060
100
050
045
0*5
140
040
0
0
0
0
0
0
0
0
0
0
0
0
.040
. 01 5
.015
.(If*
.Olb
.065
.095
.110
.100
. It 5
.055
.090
0
0
0
0
0
0
0
0
0
0
0
1)
.080
.050
.070
.120
.110
.120
.230
.170
.130
.34(J
.230
.15C
K VALUE KNOWN TO BE LESS
THAN INDICATED
-------
APPENDIX E
PARAMETRIC RANKINGS OF LAKES
SAMPLED BY NES IN 1975
STATE OF NEVADA
Mean or median values for six of the key parameters evaluated
in establishing the trophic conditions of Nevada lakes sampled are
presented to allow direct comparison of the ranking, by parameter,
of each lake relative to the others. Median total phosphorus, median
inorganic nitrogen and median dissolved orthophosphorus levels are
expressed in mg/1. Chlorophyll ^values are expressed in yg/1. To
maintain consistent rank order with the preceding parameters, the
mean Secchi disc depth, in inches, is subtracted from 500, Similarly,
minimum dissolved oxygen values are subtracted from 15 to create
table entries.
-------
LAKE DATA TO BE USED IN RANKINGS
LAKE
CODE LAKE NAME
3201 LAKE MEAD
3202 LAHONTAN RESERVOIR -
3204 RYE PATCH RESERVOIR
3205 LAKE TAHOE
3206 TOPAZ RESERVOIR
3207 UPPER PAHRANGAT LAKE
3203 WASHOE LAKE
3209 WILD HORSE RESERVOIR
3210 WILSON RESERVOIR
3211 VJALKER LAKE
MEDIAN
TOTAL P
0.016
0.193
0.094
0.005
0.057
0.173
0.403
0.114
0.049
0.602
MEDIAN
INORG N
0.340
0.350
0.050
0.040
0.165
0.125
0.130
0.320
0.120
0.080
500-
MEAN SEC
266.565
472.033
467.750
-3.269
376.000
470.000
494.555
439.400
197.333
405.333
MEAN
CHLORA
3.111
4.603
4.933
0.571
7.517
—
11.633
75.530
10.033
3.422
15-
HIN DO
11.400
10.400
10.000
10.200
14.600
3.600
7.200
14.600
11.400
15.000
MEDIAN
DISS ORTHO P
0.005
0.148
0.039
0.003
0.041
0.026
0.263
0.065
0.016
0.574
-------
PERCENT OF LAKES WITH HIGHER VALUES (MUMBER OF LAKES WITH HIGHER VALUES)
LAKE
CODE LAKE. NAME.
3201 LAKE MEAD
3202 LAHONTAN RESERVOIR
3204 RYE PATCH RESERVOIR
3205 LAKE TAHOE
3206 TOPAZ RESERVOIR
3207 UPPER PAHRANAGAT LAKE
3208 WASHOE LAKE
3209 WILD KORSE RESERVOIR
3210 WILSON RESERVOIR
3211 WALKER LAKE
MEDIAN
TOTAL P
89 (
22 (
56 (
100 (
67 (
33 (
11 (
44 (
78 (
0 (
8)
2)
5)
9)
6)
3)
1)
4)
7)
0)
MEDIAN
I.NQRG H
11 (
0 (
89 (
100 (
33 (
56 (
44 (
22 C
67 (
78 (
1)
0)
8)
9)
3)
5)
4)
2)
6)
7)
500-
MEAM SEC
78 (
22 t
44 (
100 (
67 (
33 (
0 (
11 (
89 (
56 (
7)
2)
4)
9)
6)
3)
0)
1)
8)
5)
,'IEAN
CHLORA
88 (
63 (
50 (
100 (
38 (
13 (
0 (
25 (
75 (
7)
5)
4)
8)
3)
1)
0)
2)
6)
15-
MIN DO
39 (
55 (
78 (
67 (
17 (
89 (
100 (
17 (
39 (
0 (
3}
5)
7)
6)
1)
8)
9)
1)
3)
0)
MEDIAN
DISS ORTHO P
89 (
22 (
56 (
100 (
44 (
67 (
11 (
33 (
78 (
0 (
8)
2)
.5)
9)
4)
6)
1)
3)
7)
0)
------- |