GEOLOGICAL SURVEY CIRCULAR 103 

March 1951 

UTILITY OF SELECTED WESTERN LAKES 

AND RES.ERVOIRS 

FOR WATER-LOSS STUDIES 

By 

G. Earl Harbeck, Jr., and others 

INTERIM REPORT 

ON 

LAKE HEFNER WATER-LOSS INVESTIGATIONS 
l-. i . ' 

UNITED STATES DEPARTMENT OF THE INTERIOR 

Oscar L. Chapman, Secretary 

GEOLOGICAL SURVEY 

W. E. Wrather, Director 

Washina"to.Jl, D. C. 

Free on application to the Geological Survey, Waahington 25, D. C. 
PREFACE 

This report on selected lakes and reserve~ 

was prepared iri the Water Resources Division 

of the u. S. Geological Survey, C. G. Paulsen, 

Chief Hydraulic Engineer, under the administrative supervision of R. w. Davenport, Chief, 

Technical Coordination Branch. 

Many of the data included in this report were furnished by the district engineers and. 

geologists of the Water Resources Division, 

u. s. Geological Survey, and by the regional 

directors of the u. s. Bureau of Reclamation. 

The wealth of personal knowledge of the particular areas contributed by field representatives of the Geological Survey and Bureau of 

Reclamation often more than compensated for the 

lack of published information qoncerning many 

lakes and reservoirs. 

The City water Department of Oklahoma City, 

M. B. Cunningham, superintendent and engineer, cooperated to the fullest extent in providing 

information concerning Lake Hefner. The field 

inspection was guided by Mr. Cunningham and 

s. K. Bean, civil engineer for the city water 

department. F. s. Taylor, in charge of the ' 

filter plant, provi~ed many data on operating 

details. Frank Herrmann, office engineer, 

furnished maps of the reservoir area and oper- ational data from his files. The part of this 

report describing the geology and ground-water 

conditions in t.he Lake Hefner area was written 

by E. W. Reed. Many climatological data were furnished by W.·E. Maughan, U.S. Weather Bureau, Oklahoma City, Okla. The part of this 

report describing meteorological conditions at 

Lake Hefner was prepared by members of the 

staff of R. D. Russell, u. s. Navy Electronics 

Laboratory, San Diego, Calif. 

The discussion of meteorological conditions 

at Pyramid Lake was prepared by E. R. Anderson, 

U. s. Navy Electronics Laboratory, San Diego, Calif. Much of the information on ground-water conditions at Pyramid and Walker Lakes was supplied by T. W. Robinson. Data.qn surface 

inflow wer·e furnished by L. R. Sawyer. 

General information on the hydrology of the 

Bynum Reservoir and Lake Frances area in north- ern Montana was furnished by H. w. Genger of 

the Bureau of Reclamation, Great Falls, Mont. 

J. A. Tidyman of The Valier Company, Valier, 

Mont., guided the inspecting party on its visit 

to Lake Frances and provided general climatelogical information and many operational data 

for the reservoir. The part of this report 

describiLg the geology and ground-water conditions at Bynum Reservoir and Lake Frances was prepared by A. F. Bateman, Jr. 

R. A. Work, Irrigation Division, Soil Conservation Service, Medford, Oreg., furnished 

many data on reservoirs and lakes in that area. Because of his many acquaintances among hyqraulic engineers and watermasters he was able to 

provide much essential information. 

The geology and ground-water condi_tions at 

Big Sage Reservoir in northern California were described by J. F. Poland. T. R. Simpson and 

I. M. Ingerson of the State of California Division of Water Resources, Sacramento, Calif., 

provided invaluable data on construction of 

the dam and operation of the reservoir. Victor 

Scammon of the State of California Division 

of Water Resources, Alturas, Calif., guided the inspect~ng pa~ty on its trip to the reservoir 

and furnished many operational da.ta. s. B. 

Kelley, president of the Hot Springs Valley 

Irrigation District, Alturas, Calif., contributed much historical information on conditions 

in the reservoir area before and after con- struction of the dam. 

That part of the report describing the 

geology and ground-water condi tiona at Lake 

Mathews and at Elsinore Lake in California was prepared by J. E. Upson. Many hydraulic data 

for Lake Mathews were fuTnished by R. B. Diemer 

and c. C. Elder of the Metropolitan Water 

District of Southern California. v. P. Pentegpff 

of the Corps of Engineers, Loa Angeles, was consulted on the geology and ground-water con- ditions at Lake Mathews. Current data on depths 

of Elsinore Lake were furnished by William 

Breyette of Elsinore. D. R. Crane, ci-vil 

engineer, Elsinore, was the source of information on ground-water levels and well logs in 

the Elsinore Lake area. 

B. A. Weiss and A. J. Boles of the Imperial 

Irrieation District, Imperial, Calif., supplied 

much information on Salton Sea (including data on inflow) taken from the files of the irri~­

tion district. The discussion of meteorological conditions at Salton Sea was prepared by 

members of the staff of R. D. Russell, U. s. 

Navy Electronics Laboratory, San Diego, Calif. 

III 

UTILITY OF SELECTED WESTERN LAKES AND RESERVOIRS 

FOR WATER-LOSS STUDIES 

By 

G. Earl Harbeck, Jr., and others 

INTERIM REPORT 

ON 

LAKE HEFNER WATER-LOSS INVESTIGATIONS 

CONTENTS 

Introduction ••••••••••••••••••••••••••••• The problem .•••••••••••••••••••.•••.•••.••• 

Page 

1 

2 

2 

3 

3 

4 

5 

6 

6 

7 

8 

Pyramid Lake, Nev ••••••••••••••••••••••• Walker Lake, Nev •••••••••••••••••••• • • • • Bynum Reservoir, Mont ••••••••••••••.•••• Lake Frances, Mont •••••••••••.••••••••.• Lake Abert, Oreg •••••••••.•••••••••••••• 

The search for a pilot lake •••••••••••••• Lake Hefner, Okla.· ••••••••••••••••••••••• General description •••••••••••••••••• ;. G~ology ••.••• ~ ••.•••••••• , •••••.•••••••• Big Sage Reservoir, Calif ••••••••••••••• 

Seepage •••••••••••••••••••.••••••••.••• Withdrawals •••.•••.•••.••.•••••••••.••• Inflow •••••••••••••••.••••.•••••••••••• Water budget •••..••••••••••••••••••••••• 

Elsinore Lake, Calif •••••••••••••••••••• Lake Mathews, Calif ••••••••••••••..••.•• Salton Sea, Calif ••••••••••.•••••••••••• Other reservoirs •••••••••••••••••••••••• 

Meteorolog1 cal c9ndi References cited.· •••••• · .••••.••••••••••• tiona ••••••••••••• • Conclusions ••••••••••••••••••••••••••• • 10 

Figure 

ILLUSTRATIONS 

1. Map of Lake Hefner, Okla ••••••••••••••••••••••••••••••• • • • • • • •.••• • • • • • • • • • • • • • • • 2. Graph showing area and capacity cu:rves for Lake Hefner, Okla ••••••••••••••••••••• 

3. Wind rose for Oklahoma City, Okla ••••••••••••••••• • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • 4. Map of Pyramid Lake, Nev •••••••••••••••••••••••••• • • • • • • • • • • • • ·• • • • • • • • • • • • • • • • • • • 5. Map of Walker Lake, Nev •••••••••••••••.• • •••••••• • • • • • • • • • • · • • • • • • • • • • • • • • • • · • • • • 6. Graph ~hawing area and capacity curves for Walker Lake, Nev~ ••••••••••••••••••••• 

7. Graph showing stages of Walker Lake, Nev ••••••••••••••••• •. • • ••••• • • • • • • • • • • • • • • • 8. Map of Bynum Reservoir, .Mont ••••••••••• • ••••••. • • • •· • • • • • • • • • • • • • • • • • • • • • • · • • • • • • • 9. Sketch showing seepage springs below Bynum Dam, Mont ••••••••••.•••••••••••••••••• 

10. Map of Lake Frances, Mont ••••••••••••••••••••••••• "". • •. • • • • •• • • • • • • • • • • • • • • • • • • • 11. Cross section through Chewaucan Marsh and Lake Aber•t, Oreg. • • ••••• • • • • ~ • • • • • • • • • • 1~. Map of Big Sage Reservoir, Calif ••••••••• • ••••• • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • 13. Graph showing stages of Salton Sea, Calif ••••••••••••••••••••••••••.••••••••••••• 

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18 

21 

22 

25 

26 

26 

28 

30 

Page 

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9 

11 

13 

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15 

16 

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19 

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INTRODUCTION 

Spurred by ever-increasing demands, a growing national awareness of the importance of 

water has arisen. Because the natural distribution of water supplies with respect to both 

time and place does not necessarily coincide 

with the demand, storage and transmission of 

water have long been relied upon to bridge the 

gap. In addition to the obvious and calculable 

construction and operation costs of a watersupply project, the cost or economic value of 

water lost in storage or transmission must be 

considered. Such losses are unavoidable but 

evaporation losses from bodies of surface water 

cannot as yet be prevented, and a knowledge of 

their magnitude is essential to reservoir design in order that a proper balance may be 

reached between costs of construction and 

can be minimized to a limited extent by proper 

design and operational procedure. 

Evaporation from the water surface and transpiration from vegetation in the reservoir area and along transmission. canals are non- recoverable losses. Practically speaking, 

costs of water loss by evaporation. It must 

be realized, of course, that evaporation costs are but one of many factors to be considered 

in reservoir design. 

Evaporation from reservoirs in the 17 West- ern States is roughly estimated to be 15,000,000 

acre-feet per year. This does not include 

evaporation from the water surfaces of natural 

streams--such evaporation is not properly 

attributable to reservoir construction. 

The amount of water consumed by phreatophytes 

is probably greater than is generally realized. 

In the 17 Western.States, the use of ·va.ter by 

phreatophytes, which is almost entirely 

1 
2 

nonbeneficial, may be 20 to 25 million acre- feet per year, according to unpublished preliminary figures compiled by T. w. Robinson 

of the Geological Survey. This is about twice 

the annual flow of the Colorado River. Most 

phreatophytes are found on stream bottoms and 

valley floors of the intermontane valleys. 

Although the amount of water consumed by 

phreatophytes in some reservoir areas is substantial, by far the larger part of the total 

must be ascribed to other factors. Removal of 

phreatophytes has been undertaken on an experimental scale in some reservoir areas. 

In cor.trasb to losses by evaporation and 

transpiration, seepage losses are not true 

losses in the sense that the water is permanently unavailable for use. Seepage losses 

may reduce the amount of water available for 

withdrawal from a reservoir, but the water 

apparently lost may reappear elsewhere to augment stream flow or may be available for withdrawal from wells. 

Records of evaporation from pans have long 

been relied upon and have proved quite useful as indicators of reservoir evaporation in the 

absence of more precise information; but their 

limitations are well known. In addition, many crude equations for the estimation of reservoir 

evaporation have been proposed, and some have 

been widely used. 

Reservoir losses may be computed as the difference between inflow and outflow (both 

surface and subsurface), allowing for changes 

in storage. Proved techniques have been developed for tne direct measur·ement of the last 

three items. Reservoir losses thus computed are a residual, and may be subject to large error if inflow, outflow, and changes in storage are large compared with evapotranspiration. 

A field-proved method of measuring reservoir 

evaporation directly is needed. This report 

describes the utility of several reservoirs 

and lakes for the comprehensive studies re- quired to test a number of proposed methods 

for the direct measurement of evaporation. 

THE PROBLEM 

The primary objective of this investi~tion 

was to select a reservoir or lake suitable for a comprehensive study of the exchange of energy 

between the atmosphere and a water surface. 

Because of their common interest in the basic 

theory, representatives of the Department of 

Interior and the Navy Department met in December 1948 to discuss the problem. An agreement was reached by the Bureau of Reclamation and 

the Geological Survey of the Department of 

Interior and the Navy Electronics Laboratory 

of the Navy Department to undertake a joint 

study of water losses from a pilot lake or reservoir. The ultimate objective was to determine the evaporation from Lake Mead and 

other western reservoirs and to predict evaporation losses at projected reservoirs from 

available climatological data. 

The contemplated study of water losses, and more particularly evaporation, is described 

fully by Anderson, Anderson,and Marciano (1950) 

in a separate report. Three methods are proposed to determine evaporation from the lake or reservoir: (1) water budget, (2) energy 

budget, and (3) mass transfer. In the waterbudget method evaporation is determined by 

measurements of inflow, outflow, and changes 

in storage. The energy- or heat-budget method 

involves the determination of the difference 

between incoming and outgoing energy. The mass- transfer method requires the measurement of 

certain parameters related to the factors 

affecting the transport of water vapor by turbulent diffusion. 

The second and third methods have not been 

tested adequately in the field. In this study 

the first, or water-budget, method will be 

used to determine the actual evaporation, thus 

providing a control for evaluating certain 

parameters and physical constants needed in 

the determination of evaporation by the second 

and third methods. 

The need for an accurate water budget is 

therefore a prime consideration. At first 

thought it might seem that many lakes and 

reservoirs exist for which accurate water bud~ 

ets can be obtained. In a sense this is true 

because inflow and outflow from many reservoirs can be measured by ordinary methods to within, 

say, 5 percent. For this study, however, it is 

necessary to determine accurately the differ- ence .between inflow and outflow. If the inflow 

and outflow are large compared with evaporation, small errors in their measurement may 

be large compared with evaporation. A comprehensive evaluation of many lakes and reservoirs was therefore necessary before a site for the 

water-loss studies could be chosen. 

THE SEARCH FOR A PILOT LAKE 

In December 1948, representatives of the 

Geological Survey, Bureau of Reclamation, and 

Navy Department discussed specifications for a lake or reservoir to be used for the wa tarloss studies. In January 1949 the regional 

directors of the Bureau of Reclamation were asked to submit names of suggested reservoirs or lakes and information concerning them. 

The suggestions of these regional directors were studied, and inquiries also were made of 

certain field offices of the Geological Survey. 

At that time it was contemplated that the 

studies would be made only during the summer months when evaporation rates are high. In 

California rainfall and runoff are generally 

low in summer, thus improving the prospects 

of determining the water budget accurately. 

The reservoirs first investigated were therefore in California. The results·of these investiga tiona were presented to representatives 

of the three agencies at a meeting in Boulder 

City, Nev., on July 21-22, 1949. It was con- cluded that none of the lakes and reservoirs 

previously investi~ted could be used for the 

study. The requirements were revised and listed 

in detail at that meeting. In order of importance they are as follows: 

1. Water budget. a. The error in the monthly difference between total inflow and outflow, including both surface. and subsurface, allowing for changes in storQge (including 

bank storage), must be less than 5 percent of the best present estimates of 

the mean monthly-evaporation loss. It 

is desirable that inflow and outflow 

be as small as possible during the 

period of high evaporation. 
b. Infrequent short periods of storm inflow, 

during which the water budget cannot be 

determined with the accuracy required under la, can be tolerated. c. Subsurface inflow and outflow must be 

negligible compared with evaporation, 

unless it is known that they can be 

measured accurately. 

d. Substantial bank storage is undesirable. e. Transpiration losses must be small. 

f. An accurate area-capacity curve is needed, 

but if not available a hydrographic 

survey can be made. 

2. Size. 

a. The minimum desirable size is 3 miles in 

width and 5 miles in length or an area of 10 square miles if the water body 

is nearly circular or if the longer 

dimension is in the direction of the 

prevailing summer winds. 

b. The maximum desirable size is 50 square 

miles if the lake is nearly circular, 

otherwise 30 square miles. Larger lakes 

(50 to 200 square miles) may be considered if other requirements are met, but more equipment will be required arid 

cost therefore increased. 

3. Shape. 

a. A circular shape is ideal. A very irregular shore line is unsatisfactory; an irregular shore line downwind is not as objectionable as one upwind. A long, narrow lake is not satisfactory. 

b. An unobstructed expanse of water (few or no islands) extending 5 miles in the 

direction of the prevailing summer winds 

is desirable. 

4. Depth. 

a. Not more than 20 percent of the lake sh~ 

be less than 5 feet deep (and prefera~ 

not less than 10 feet). A deep lake is 

desirable. 

b. Playa lakes should be considered if they 

meet all requirements except depth. 

5. Topographic setting. a. Low relief is preferable; lakes in cany~ 

are not satisfactory. 

b. The drainage area preferably should be 

smalL 

6. Location and climate. a. An arid region is preferable. 

b. There should be fairly long periods of no rainfall during the season of high 

evaporation, but infrequent storms are are not objectionable. c. It is preferable, but not essential, that 

the lake does not freeze in the winter. 

A list of lakes.was prepared for which more information was required. Many of these were selected because on the maps available they were seen to approach the desired shape and 

size. This list of lakes and a copy of the 

specifications was sent to the district offices 

of the Water Resources Division of the Geological Survey in the Western States. It wa·s requested that information be submitted for 

each of the lakes listed and for any others 

that appeared to meet the specifications in 

most respects. Lakes in the humid region were not considered because of the improbability 

that the water budget could be determined 

with the required accuracy. 

The replies were reviewed by the three 

agencies, and at a meeting in San Diego September 12-13, 1949, a number of lakes were selected as needing further inve.stigation. 

Lake Hefner, near Oklahoma City, Okla., was· 

3 

recommended strongly by local Geologlcal Survey engineers and geologists for further investigation. For some of the suggested lakes, 

available data on which to base a decision were lacking; for some of the others the information indicated that these lakes were worthy of field investigation. 

September 14-15, 1949, a reconnaissance was made by Navy plane over western Nevada, south- ern Orego~, and northern California. The party 

included R. D. Russell, u. s. Navy Electronics 

Laboratory, San Diego, Calif.; w. 0. Smith and 

G. E. Harbeck, Jr., U. s. Geological Survey, 

Washington, D. C.; and W. U. Garstka, U. S. 

Bureau of Reclamation, Denver, Colo. Modern 

maps of much of the region do not exist, but on the basis of observations from the plane 

it was possible to eliminate most of the suggested lakes and reservoirs in this area be- cause of unsatisfactory shape, size, or sur- rounding terrain. 

September 16-17, 1949, representatives of 

the thr~e agencies visited the Salton Sea area. The remaining lakes considered worthy 

of field investigation were then visited during September 19-30, 1949, by a group that 

fncluded W. u. Garstka, w. o. Smith and G. E. 

Harbeck, Jr.,mentioned above, and E. R. Anderson, u. s. Navy Electronics Laboratory, San 

Diego, Calif. This group was accompanied by 

·representati vas of the various district offices 

of the Geological Survey. 

Preliminary reports were prepared to summa- rize. the results of the field investigations. 

These reports were studied at a meeting held 

at Boulder City, Nev., October 17-19, 1949. 

At that meeting Lake Hefner, at Oklahoma City, 

Okla., was selected as the site for the waterloss s;tudies. 

The following reports on lakes and reser- voirs in the Western States were prepared to 

make clear the reason for tne choice of Lake 

Hefner and to make the data collected available 

to those engaged in studies of evaparation or general limnology. 

LAKE HEFNER, OKLAHOMA 

General description 

Lake Hefner is a reservoir completed in 

1944 by Ok~ahoma City for its municipal v~ter 

supply~ It is in the southeastern part of 

T. 13 N., R. 4 w., about 8 mi~es northwest of 

the center of the city. According to area- capaciv,r tables furnished by the city water 

department, its capacity at full pool (elevation 1,199) is 75,681 acre-feet and its sur- face area 2,595 acres. The lake, fairly regular in shape, is formed by a long horseshoeshaped dam on Bluff Creek. (See fig. 1.) The 

dam, about 3l miles long with a maximum height 

of 105 feet (from thalweg to road on top of 

dam), is of rolled-earth fill with a clay core and a seepage collection system. 

The lake is supplied principally by· a canal 

from the North Canadian River, although it 

lies in the Cimarron River Basin. In. the 

Oklahoma City area the North Canadian River 

is at an elevation several hundred feet higher 

than the Cimarron River, and only a short 

diversion canal was needed to permit gravity 

flow of selected water from the North Canadian 
4 

21 24 

26 

LAKE 

HEFNER 

4 

5000 0 5000 

Figure 1. -- Map of Lake Hefner, Okla. 

River into Lake Hefner. The natural drainage area of Bluff Creek and other contributing 

streams above the dam is 3,156 acres, excluding the area of the lake surface. In addition, 

runoff from an area of about 200 acres discharges into the intake canal and thence into 

Lake Hefner. The drainage area above the lake 

is only about 30 percent greater than the area of the lake at full pool. 

Geology 

Except where covered by alluvium, the Hennessey shale of Permian age is the surface 

formation of the Lake Hefner area. It is primarily red shale containing a few thin, lenticular sandstone beds. The formation crops 

out ·in a north-south band covering the western 

third of Oklahoma County and dips westward at a rate of about 40 feet per mile. The thickness of the Hennessey shale in Oklahoma County 

ranges from a feather edge along the surface 

contact with the underlying Garber sandstone 

in the central part of the county to about 

650 feet at the western edge of the county. 

As Lake He£ner is near the middle of the·outcrop of the Hennessey shale, it is underlain 

by more than 250 feet of the shale. 

Bluff Creek and its tributaries have cut 

back into a high terrace of the North Canadian 

River about a mile south of Lake Hefner. This 

terrace consists of unconsolidated sand, 

gravel, and clay deposited by the North cana- dian River in some past period when the river was at a much higher elevation and probably 

had a much grea tar flow than a,t present. The 

terrace, now equivalent in area to a single township, was at one time a wide flood plain. 

The terrace is now being actively dissected 

by tributaries of both the North Canadian and 
the Cimarron Rivera, and the divide between 

the two systems is now on the terrace. The 

deposits underlying the terrace contain relatively large amounts of water, and many wells, 

including those supplying the city of Bethany, 

have been drilled into it. 

The Hennessey shale underlying the reservoir 

weathers to a dark soil that is readily eroded 

and shows relatively little relief. The thin 

soil layer is grass-covered. Trees, mostly 

cottonwoods and willows, are found only along 

the watercourses where the soil is thicker 

and capable of storing water. 

Seepage 

The Hennessey shale is practically imperme- able, and any recoverable water in the shale 

is believed to be contained in joints and 

fractures. Moat of the wells tapping the Hennessey shale are farm wells, and the few towns 

that use water from this formation have wells 

of low yield. No pumping tests to determine 

permeability have been mad~ on any well in the 

Hennessey shale, but from the yields of these 

wells it is evident that the permeability of 

the sandstones in the Hennessey shale is less 

than that of the underlying Garber sandstone. 

Tests on sandstone of the Garber show its permeability to be about 40 gallons per day 

through an aquifer 1 foot in thickness and 1 

mile in width under a hydraulic gradient of 

100 percent (Meinzer's units). No faults are known to be in the Hennessey shale, and the 

possibility of seepage of any important quantity of water into or out of the lake through 

the Hennessey shale seems remote. 

Because the regional dip of the strata in 

this area is westward, a cross section was se- lected along the western side of Lake Hefner 

for use in computing approximately the possible 

magnitude of deep seepage. The length of the cross section from the northern end of the 

lake to the southern end of the dike is approximately 10,000 feet. Its thickness was assumed 

to be 100 feet. The hydraulic gradient is 

assumed to conform to the regional dip of 40 

feet per mile. The field coefficient of permeability was assumed to be 40 gallons per day 

(Meinzer's units). This is an average figure for the Garber sandstone; the permeability of 

the Hennessey shale is believed to be much 

less. From these data, the maximum deep-seepag9 

loss is computed to be 300,000 gallons per 

day, or.0.9 acre-foot per day. As will be 

demonstrated later, this figure is of little 

practical significance when compared with 

other items included in the water budget. The 

so-called "wet-weather springs" in the Hennessey shale are caused by rainfall percolating 

down through the thin soil mantle and along 

the contact with the shale or sandstone until 

it reaches the outlet. Very little of the precipitation on the outcrop actually enters the 

Hennessey shale. 

Construction of a series of fish-rearing 

ponds in the area west of the sludge pond was under way during early 1950. Construction of a canal, a part of the seepage-collection 

system, necessitated excavation into the previously undisturbed shale to a depth of 3 or 4 feet. The newly exposed shale was dry when 

inspected in January 1950. 

5 

There are, however, small but measurable 

shallow seepage losses from the reservoir. Be- cause seepage from the reservoir is a functic·n 

of reservoir stage only, it is essential that 

measurements of seepage be made during dry 

periods when there is no surface runoff from 

the area below the dam. The possibility of defining the relation of seepage to reservoir 

stage does not appear probable, because the 

range in reservoir stage is relatively·small. 

However, a series of seepage measurements at 

weekly or biweekly intervals during dry periods 

should provide adequate data on collected 

seepage. 

Any seepage that occurs beneath or through 

the dike along the northern and western sides 

of the lake is collected by a series ot drain~ 

Along the northern side of the dam, between 

the west line of sec. 24 and the center of sec. 28, seepage collects and drains into the 

old Bluff Creek channel below the dam. 

Operation of the sludge pond west of the 

filter plant (see fig. 1) at times complicates 

the de~ermination of seepage in this area. When filters are washed, the wash water is 

discharged into the sludge pond, usually caus- ing it to overflow through the morning-glory 

spillway and temporarily to increase the flow 

of Bluff Creek below the dam. From time to 

time small quantities of water are recovered 

from the sludge pond by pumping. This water 

does not, however, pass through the raw-water 

venturi meter. Under normal conditions, filter 

wash water is not being discharged into the 

sludge pond and the recovery .Pump is not in 

operation, so that, neglecting evaporation 

from the pond, the amount of water leaving 

the sludge pond by spillway overflow and gate 

leakage is equal to seepage into the sludge 

pond. A recording gage below the sludge pond is essential to determine when seepage meaaur~ 

menta can be made without the complicating effect of sludge-pond operation. Seepage from 

the dam will be relied upon to furnish sufficient water to keep the fish-rearing ponds 

full. It may prove necessary to adjust the 

measured quantities of seepage for the loss 

by evaporation from the fish-rearing ponds 

and from the sludge pond. 

Most of the seepage from the west side of 

the reservoir is collected in a ditch paralleling the dam. It flows northeast along the dike 

to a point near the north quarter corner of sec. 27 and thence in a northerly direction. 

A small pond in the NWi sec. 27 also drains 

northeast, paralleling the mai,n drainage ditch. 

The two seepage channels join near the center 

of sec. 22 (see fig. 1) and reach the Bluff 

Creek channel at a point approximately 1,000 

feet south of the north line of sec. 22. 

Several small seepage areas were noted in the swi sec. 22. At one of these, a spring issues 

from a small depression in an open field and 

flows into the westernmost of the two seepage 

channels previously described. There are sev- eral uncontrolled farm pond~-perhapa.an acre in extent--in the si sec. 22. They are kept 

filled by seepage and overflow continuously. 

The flow of Bluff Creek where it crosses the 

highway along the north line of sec. 22 (location EE on fig. 1) includes 'the seepage from 

the area along the northern side of the reser- voir, west of the filter plant. The seepage 

flow measured at EE on April 7, 1950, was 0.89 

cubic foot per second, or 1.8 acre-feet per 

day. 
6 

Along the west aide or the reservoir a num- ber or small seepage areas' discharge into a tributary. that joins Bluff Creek about ::l miles 

below the dam. Seepage can be measured at locations AA, BB, and CO (see fig. l) at culvert~ 

under the highway. A fourth seep, DD, has its 

origin in marshy areas. on both sides of the 

highway, a11d can be measured just above its 

confluence with Silver Lake outflow. The total 

flow of the four seeps, AA-DD, inclusive, on April 7, 1950, was 0.07 cubic foot per second, or 0.1 acre-foot per.day. 

In the area east of the filter plant several 

seepage areas discharge into a small stream 

channel. During a period of dry weather it was noted that small tributaries from the west or reservoir side of the stream continued to flow, 

but tributaries from the east side were dry. 

It was therefore concluded that the observed 

flow was seepage from the reservoir. There are several small marshy areas below the spillway 

in the NW~ sec. 25. Discharge from these marshy areas flows under Hefner Road near the south 

quarter corner of sec. 24. The flow from a small seep in the Swf sec. :34 joins the seepage from the spillway area just below Hefner 

Road. Other minor seepage areas in sec. 24 

contribute minor amounts, and the total seepage can be measured at point FP on the north 

line of sec. 24. (See fig. 1.) The measured 

seepage flow at FF on January ~5, 1950, was 0.17 cubic foot per second, or 0.3 acre-foot 

per day. 

Withdrawals 

Water is released from Lake Hefner through a 48-inch raw-water main. Outflow rates are measured with a venturi meter. The recording 

device is actuated by a mercurial manometer, 

and the difference in head, converted to equi~ 

alent rate of flow in million gallons per day, is recorded on a circular chart in the filter 

plant. A cam-actuated totalizing device reg- isters total flow. Although the manufacturer's 

rating for the venturi meter is quite adequate 

for the needs of the city water department, it 

is essential that, for the purposes of this 

study, the venturi meter be calibrated in order 

that reservoir withdrawals may be measured as accurately as possible. It is estimated that, 

after calibration, the error in measuring wi~ 

drawals will not exceed 3 percent and may be 

substantially less. 

Reservoir withdrawals are the major item in 

total outflow from Lake Hefner. Combined ca- pacity of t~e three pumps is ~4 million gall~ 

per day (73.7 acre-feet per day), but filter capac~ty limits the maximum possible withdrawal 

to a peak rate of approximately 22 million 

gallons per day. During daytime hours in the summer months the ordinary peak rate of flow 

usually is 18-~0 million gallons per day, with a .total of 15 million gallons for the entire 

24-hour period. During nonsurnmer months pumpage is somewhat less, averaging perhaps 6 million 

gallons per day. 

Inflow 

Tha major source of inflow to Lake Hefner is 

the canal from North Canadian River. (See 

fig. 1.) During the 3-year period ending September 30, 1949, substantial volumes of 

inflow occurred during 11 periods totaling 64 

days, or an average of 21 daJB per year. Ave.rage inflow on those days was approximately 

1,000 .acre-teet. Because ot the ,relat'lvelr . large volumes or water c~ncerned, it 1s not 

certain that the water-bUdget accuracy requirement can be met on days when canal. 1ntlow ia · of this magnitude. A 5-percent error in meaa~ 

uring inflow would amount to 50 acre-teet, · which is approximately equal to the average 

daily evaporation. With frequent discharge 

measurements during the infrequent periods of 

high inflow it may be possible to compute 

weekly reservoir losses with sufficient accu- racy. 

A small amount of natural flow also reaches 

the reservoir through the intake canal. The 

canal cuts across the previously described 

Bethany terrace and intercepts part of the sur- face- and ground-water flow that formerly reached the stream that enters Bluff Creek as a tributary from the west several miles below 

the dam. Part of the canal is paved, and. drain 

tile has been installed beneath the paved sec- tion to.prevent "floating." The water thus 

drained is discharged into the arore-mentione4 

Bluff Creek tributary, which bypasses the lake. 

A sniall amount of ground water drains into the 

canal and is conveyed into Lake Hefner. Storm 

runoff from an area of approximately 200 acres also drains into the canal. A recording a-ge 

and an artificial control are required to meas- ure this flow. The best site appears to be at 

the point of emergence of the siphon, about 

one-half mile above the lake, where a wide 

broad-crested concrete weir has been provided~ 

As normal ground-water discharge is ab.out 0.5 

cubic foot per second, or 1 acre-foot per day, 

the existing concrete weir is too insensitive,. 

and a small rectQ.ngular weir is needed for · precise determination of low flows. · 

Excluding the intake canal, the natural 

drainage area above full pool elevation of 

1,199 feet is 3,156 acres, based on a transitstadia determination by s. K. Bean, civil 

engineer of the Oklaho~ City Water Department. 

Of the total area, 2,484 acres lies· above the 

road that encircles the southern end of the 

lake. The size of the area lying be_tween the 

road and tqe lake varies with reservoir stage but is 672 acres when the lake stage is 1,199 

feet. 

The major stream that flows into the reser- voir is Bluff Cre~k, which has a drainage area of 1, 037 ac.res a-bove the encl. rcling road •. The 

headwater tributaries of Bluff Creek drain 

part of the Bethany terrace, and the perennial 

flow of Bluff Creek is derived from ground 

water in that area. A recording gase and artificial control at the road bridge (location 0 on fig. 1) are required to measure Bluff Creek 

flow. 

The remainder of the storm runoff is carried 

under the encircling road by concrete culverts, 

thus limiting the number of points at which 

inflow must be measured. Records of flow are required at 8 points (locations, A, B, D, B, F, 

G, H, Jon fig. 1). These may be obtained with 

sufficient accuracy if a weir is installed at 

the entrance to each culvert. A crest-stage 

gage is required at each location to record 

the peak stage reached during storm runoff. 

One or more points on the recession hydrograph can be obtained by direct observation. Based on continuous recorda of Bluff Creek flow and 

rainfall in the reservoir area, the'discharge 
hydrograph at each inflow point may be estimated with sufficient accuracy. 

According to s. K. Bean, inverts of all culverts have been set at elevation 1,199, the 

maximum reservoir stage. This has resulted in 

the formation of small pond areas on the upstream side of several culverts. Flow through the culverts takes place only when the pond 

levels have risen to the culvert invert elevation. During many storms runoff is insufficient 

to raise the ponds to the overflow point, and 

inflow to the lake does not occur. 

The possible error in measuring storm inflow 

to Lake Hefner is small compared to the possi~ 

error in measuring rainfall on the lake sur- face. Discharge of Bluff Creek and the intake 

canal can be measured with sufficient accuracy 

except possibly for a few short periods of 

high flow each year. Estimates of flow through the culverts and from the ungaged area are subject to fairly large percentage errors, but 

the actual magnitude of those errors is small. 

During minor floods, runoff is seldom greater 

than one-third to one-half of the flood-produc- ing rainfall. On a.n ann11al basis the differ- ence between rainfall and runoff is even more striking. Rainfall at Oklahoma City, from U. S. 

Weather Bureau records, averages 31.76 inches 

annually. Average annual runoff in this area is between ~.5 and 5.0 inches, according to 

Langbein (1949, pl. 1). The total drainage area above full-pool elevation is 3,156 acres, com- pared ~ith a lake-surface area of ~,595 acres, as taken frcm the area-capac!~ table of the 

city water department. As the area of the lake 

surface is nearly as great as that of the 

tributary drainage basin, rainfall on the lake 

surface is a m~ch larger item in the water 

budget than is runoff from the area above the 

lake. Therefore, possible additional refinements in measuring inflow do not appear justi- fied. 

Rainfall on the lake is a large item in the 

water budget, and a dense network of rain 

gages will be required. It is proposed to place 

recording rain gages at each of the meteorological stations and 18 nonrecording gages spaced as uniformly as poseible around the 

lake. It is planned to install a recording 

rain gage on the barge in the middle of the 

lake on which meteorolog1cal equipment will be 

placed. A municipal golf course is under con- struction on the south side of Lake Hefner. It 

is proposed to irrigate the new greens and 

fairways with water pumped directly from the 

lake. The maximum pumpage contemplated is 

250,000 gallons, or 0,8 acre-foot, per day. 

The metered withdrawals from the lake present no problem, but the possibility of return flow 

from irrigation cannot be ignored. Records of 

water-level elevations at several test wells 

in the area between the golf course and the 

lake will be necessary to determine whether 

return flow is reaching the lake and, if so~ 

to estimat~ the quantity. It appears improbable 

that the quantity will be sufficiently large 

to warrant inclusion in the water-budget calculations. 

Water budget 

An approximate average monthly water budget 

has been estimated in order to illustrate the 

rela. ti ve magnitude of the q,.l8.nti ties involved, 

when there are no diversions from North 

7 

Canadian River. Estimates of the probable upper 

lim! t of measu1•ement errors have been shown. 

The reservoir is assumed to be full at the beginning of the month (contents 75,681 acre-feet, 

surface area 2,595 acres, from city water department area-capacity table.) (See fig. 2.) 

Annual reservoir evaporation at Oklahoma City 

is estimated to be about 66 tnches; January 

evaporation is estims.ted to be J..5 inches and 

July evaporation to be 10.2 inches, according 

to the American Society of Civll Engineers 0949, 

p. 127, table 15).At these rates monthly evaporation from Lake Hefner averages 324 acre-feet 

duririg January and 2, 210 acre-feet during July. 

Item 

Inflow: 

Natural runoff 

Rainfall on lake 

Irrigation return 

flow 

Total 

Outflow: 

Seepage 

To filter plant 

Golf-course 

irrigation 

Total 

Loss in storage 

Eva.po ration 

Quantity Measurement error 

~ere-feet (percent)(a.cre-fee.t 

per month) per month) 

43 ±5 ±2.2 

572 ±5 ±28.6 

__ 1_ ±100 tl.O 

616 

69 ±10 :1:6.9 

·737 ±3 ±22.1 

____!g_ ±5 :t0.6 

818 

1,392 :1:25.6 

1,190 

The loss in storage was computed by subtracting inflow from the sum of outflow plus evaporation. The error was computed by assuming that the .error in the measured change in stage 

will not exceed 0.01 foot. 

It is required that the error in the differ- ence between inflow and outflow shall not ex- ceed 5 percent of the mean monthly evaporation. 

The error in measuring change in contents 

must, of course, be included. For short periods 

of time, change in contents becomes the con- trolling factor. During pericds of high winds, 

it is doubtful that changes in stage can be 

measured closer than 0.01 foot. On this basis 

daily evaporation as CC":"'puted from the water 

budget is subject to a possible error of 65 

percent, and weekly evaporation an error of 9 

percent. A week, therefore, appears to be the 

shortest interval for which dependable evapora- tion figures can be obtained, exce )t during 

periods when nocturnal winds are light, so that 

midnight stages can be accurately determined. 

The errors shown in the table are believed 

to represent the maximum error to be expected. 

For average months the errors in 1:-1onthly values 

in any item may be expected to follow the nor- mal law of error. The variance of the sum of a. number of i terns is tbe sum of tne variances of 

the individual items. If the errors in the 

individual items be conservatively considered 

to represent two standard deviations (i.e., it 

is expected that they may be exeeedod once in 

20 times), it is also to be expected that the error in their sum will exceed 44.9 acre-feet 

only once in 20 times, on the average. The 

maximum allowable error 1.n the sum is 59.5 

acre-feet, which is 5 percent of the evaporation. The probability is 8 in 1,000 or a. little 

less than 1 in 100 that thls figure will be 

exceeded. The probability that the maximum error in all items Will occur simultaneouslyis 3 in 10,000, or about 1 in 3,300. 
8 

Surface area~ in thousands of acres 

(Data from City Water Department., Oklahoma ~i~y, Okla.) 1120~------+-------+-------~------~~----~--~--~~~--~------~ 

~ 

~ 

.a 

:1 

< 1100 ..... __ ------'------'-------L------'------~~------~~---'------' . 0 ' 10 20 30 40 50 60 70 80 

Capacity~ in thousands of acre-feet 

Figure 2.-- Graph showing area and capacity curves for Lake Hefner~ Okla. 

It is anticipated that during major s,torms 

it will be impracticable to obtain sufficiently 

accurate records of rainfall and runoff. Ayerage daily evaporation is approximately 40 acre- feet. An inch of rainfall on the lake surface 

amounts to 216 acre-feet at full pool. A 5-

percent error in the determinatio~ of average rainfall amounts to 10.8 acre-feet, or more than ~5 percent or the daily evaporation. The error in measuring total storm runoff from the 

gaged and unaaged areas is probably greater 

than 5 percent, but runoff is small in compari- son with rainfall. The accuracy of the water 

budget during major storms is limited pr1maril1 by the accuracy of the determinat1on of rainfall on the lake. A study of the areal variability in rainfall as measured by the network 

of rain gages will indicate the magnitude or the possible error in the determination or pre- cipitation on the reservoir surface. 

The frequency of storm rainfall has been investigated. For the 10-year period 1939-48, 

the frequency of daily precipitation is as follows: 

Daily precipitation 

in inches 

0.50 - 0.99 

1. 00 and greater 

Average number of occurrences per year 

13 

10 

The number of days which had rainfall of 1 

inch or greater ~~·significantly greater for 

the months of April, Hay, and June. A succes- sion of several days of heavy rainfall was not. uncommon. Therefore, although on the average it may be expected that daily precipitation will be 1 inch or more on 10_ day~ each year, 

the number of storm periods would be somewhat 

less. 

The area-capacity table for Lake Hefner used 

by the city water department was prepared on the basis of a topographic survey made prior 

to the construction of the dam. Although the 

existing table is entirely adequate for opera- tional purposes., a complete hydrographic survey of the lake will be required to determine the 

amount of deposition of sediment, if any, since the reservoir was filled, and the amount 

of overburden removed for constr.ucti_on of the 

embanlonent. The 1•esurvey should be particular~ 

precise in the area covered by the top few 

feet of water ip order that the changes in 

volume and area resulting from small changes in stage may be accurately determined. 

Meteorological conditions 

Meteorological conditions at Lake Hefner are favorable for water-loss studies. Because the 

surrounding topography is gently sloping, the. 

wind structure is not dis_torted by mechanicalJ1' 

induced turbulence except in the area near the 

dike. Northerly and southerly winds predominate, as shown in figure 3. The following table 

(Weather Bureau, .Oklahoma City' shows the 

J1 verage monthly wind speeds at the U. S. 

Weather Bureau station in the residential sec- tion of Oklahoma City. 
Based on hourly 

observations at 

municipal airport during the 

years 1936 - 45 

(af'ter U.s. Wea trer 

Bureau, Oklahoma 

City, Okla.) 

N 

(10,3) 

(21.4) 

s 

Legend 

miles 

A 

32 & over 25 - 31 

24 - 13 

12 - 1 

·calltl 0.4% 0 (in center) 

( ) Total % each 

wind direction 

Figure 3. -Wind rose for Oklahoma City, Okla. 

Month. Average Month Average wind wind 

speed speed (miles per (miles per hour) hour) 

Jan. 11.2 July 9.3 

Feb. 12.2 Aug. 9.0 

1'1ar. 13.3 Sept. 10.3 

Apr. 13.1 Oct. 11.1 

May 11.6 Nov. 11.1 

June 10.7 Dec. lb..! 

Yearly avg. 11.1 

The winds at Lake Hef'ner are expected to have a speed of approximately 5 miles per hour 

greater than tl:ose observed at the city station. 

The maxim1~ 5-minute average speed at Lake 

Herner may approach 60 mile~ per hour. 

The humidity at Oklahoma City is shown in 

the f'ollowing table (Weather Bureau, Oklahoma 

City). Prior to July 1g39 observations were made at the city off'ice, but since 1939 the 

data have been obtained at Will Rogers Field, 

9 

approximately 7 miles southwest of' the city off'ice. 

Month Relative humidity 

in percent at 

indicated time 3~00 8:30 12:30 6:30 

a.m. a.m. p.m. p.m. Jan, 77 80 62 65 

Feb, 74 79 57 60 

Mar. 71 76 50 53 

Apr. 73 77 51 52 May ·77 82 5"'7 59 June 79 82 55 57 

July 73 79 48 51 

Aug •. 71 79 47 51 

Sept. 69 81 51 55 

Oct.· 72 79 53 57 

Nov. 72 78 56 61 

Dec. 76 80 61 66 

Year 74 79 54 57 

======== Years of' record 9 58 31 58 

Two series of' humidity measurements were made at Lake Hef'ner on September 30, 1949, 

using a sling psychrometer. Between 10:00-

10:15 a.m. at the upwind shore the wind was f'rom south-southeast and its speed was estimated at 20 to 25 miles per hour. At the downwind shore the wind was also from south-southeast; its speed was 30 to 35 miles per hour 

and it was very gusty. Average wave heights on the lake were 1.5 feet, with a maximum of 4 

f'eet. The wave length was estimated to be 15 

feet. Wave data were estimated from the downwind shore. Measurements of humidity at this 

time showed a vapor-pressure diff'erence (downwind minus upwind) of' 2.9 millibars. Relative 

humidity at the upwind location was 42 percent; 

at the downwind location, 53 percent. 

The second set of' measurements was made in 

the af'ternoon, f'rom 2:15 to 2:30 p.m. The wind was south-southeast at 15 miles per hour. Wave 

heights were approximately 0.5 f'oot. The vaporpressure dif'ference was 2.0 millibars. Relative 

humidity at the upwind location was 32 percent; 

at the downwind location, 43 percent. 0 The 

water temperature at thi a time was 69 F., indicating a vapor-pressure dif'f'erence of' 19.7 

millibars between the vapor pressure of' saturated air at the temperature of the water and 

the actual vapor pressure of the air at psychrometer level. The grass on the south side 

of the lake averages about 12 inches in height, 

indicating a roughness parameter of approximately 6-7 centimeters f'or light winds, and 

3-4 centimeters f'or strong winds that f'latten 

the grass and thus create a smoother surf'ace. 

A third series of humidity measurements were made on October 3, 1949. The wind was southsouthwest, 5 to 10 miles per hour at the upwind (south) shore, 0 to 3 miles per hour at 

the downwind shore. The average of 8 readings 

at the upwind location indicated the relative 

humidity was 77 percent; the average of 13 

readings at the downwind location indicated 

the relative humidity was 82 pe~cent. The 

vapor-pressure difference (dovmwind minus upwind) was 1.4 millibars. 

The humidity measurements, and particularly 

the last set, which were made under conditions 

of light winds and high humidities, indicate 

that the vapor-pressure difference is easily 

measurable. The humidity equipment to be used 

will measure a difference of 0.2 m~llibar. 
10 

Conclusions 

Lake Hefner is believed to meet more of the 

requirements for the water-loss studios than 

any othor of the reservoirs investigated. A 

somewhat larger lake would be desirable, but 

Lake Hefner is reasonably regular in shape, and preliminary meteorological observations 

'indicate that humidity differences across the 

lake are measurable. The general wind structure 

is uncomplicated by orographic effects. More 

detailed investieations are required of certain 

factors affecting the water budget, such as a more precise determination of possible deepseepage losses and a test of the venturi meter 

rating. A careful study of the relative magnitudes of the quantities involved in the water 

budget and of the errors of measurement leads 

to the cQnclusion that the evaporation from 

Lake Hefner can be determined by the waterbudget method with acceptable accuracy for a large parto~ the time. It wae on the basis of 

these facts, therefore, that the repr~sentati vee of the Geologi e~al Survey, B.urea u of 

Reclamation, and Navy Department agreed that 

the water-loss studies should be conducted'at 

Lake Hefner. · 

PYRAMID LAKE, NEVADA 

Pyramid Lake lies in a closed basin in 

Washoe County, Nev., approximately 40 miles 

northeast of Reno. It is supplied by inflow 

from Truckee River, but since shortly after 

the turn of the century, much of the natural 

flow of Truckee River has .been diverted for 

irrigation, thus accelerating the decline in 

lake levels that has continued since about 

1870. The lake is now approximately 8 miles 

wide and 22 miles long. 

Pyramid La~e is sheltered by mountain ranges-- the Virginia Range rising on the west to more than 4,000 feet and the Lake Range on the east 

side to more than 2,000 feet. (See fig. 4.) 

Russell (1885, pl. 3) noted, on.each side of 

the long axis of the lake, the existence of a major fault marked by the edges of upheaved 

blocks of basalt. The lake occupies part of 

the bed of the Pleistocene Lake Lahontan, 

which was first described in detail by Russell 

(1885) who visited the region in 1881-83. 

According to Jones (1925, p. 3), ''only the 

valleys in the western portion of Nevada were occupied by Lake Lahontan. The great peninsulas and islands formed by the mountain ranges impressed an exceedingly irregular shore line 

upon the lake. At. the time of the greatest expansion of the water surface it covered an area of about 8,500 square miles, and as the surfa~e of the lake fell and uncovered the 

different divides, it separated into a number 

of independent smaller bodies of water. At 

present these subsidiary basins are all in a state of dessication. Some retain permanent 

bodies of water, such as Pyramid, Winnemucca, 

and Walker Lakes; others may go entirely dry 

in exceptionally dry years, as Carson,_ Honey, 

and Humboldt Lakes; still more are playas, 

covered with water for only brief periods of 

the year, as the Black Rock and Smoke Creek 

Deserts." Winnemucca Lake, however, has been 

dry since 1939. 

The lacustrine sediments deposited during the life of Lake Lahontan were classified by 

Russell (1885, p. 125) into three divisions: 

upper lacustral clays, medial gravels, and · 

lower lacu1tral clays. The lacustral marly clays are fine and evenly laminated. Nea~ the 

mou:t;h of Truckee River only t.he upper clays are exposed. On the basis of a field examination, these beds are considered relatively 

impermeable. Probably the present lake bed is 

composed of essentially similar deposits. 

The surface-water supply of Pyramid Lake 1s 

derived from Truckee River. The average daily di&~harge of Truckee River into the lake is 

estimated to be approximately 50 cubic feet 

per second, or 36,000 acre-feet per year. During the flood of December 1937, peak di.scharge 

of Truckee River at Reno was approximately 

13,000 cubic feet per second, indicating that 

much larger volumes. of inflow may occur, m1t 

flows of this magnitude are infrequent and of 

short duration. 

Also.flowing into Pyramid Lake are a number 

of small, ephemeral streams that drain an area of approximately 315 square miles. Average 

annual runoff in this region is 0.25 inch or less, according to Langbein ( 1949, pl. 1). 

Using the figure of 0.25 inch, average annual 

inflow from this source is 4,000 acre-feet. 

There is little information available on the 

voluwe of ground-water flow into Pyramid Lake. 

'!Wo .small springs were observed near the water's 

edge on the southwest side of the lake. A 

distinct odor of hydrogen sulfide was noted. 

Total discharge from the two springs was estimated to be about 0.5 cubic foot per secon4, or 400 acre-feet per year. The proprietor of an inn at Sutcliffe, on the west shore of the 

lake, reported that domestic water supplies are obtained from springs in the mountains 

and from wells in the alluvial fans. The 

Southern Pacific Lines have a well near Sutcliffe for feed-wa.ter supply and another at 

Big Canyon. 

The eastern side of the lake is inaccessible 

by road and ~s not inspected. The aerial 

reconnaissance on September 14, 1949, revealed no perennial streams flowing into the lake, 

but ground-water conditions could not be determined. 

There are evidences of ancient hot springs near the south and north ends o.f the lake. It 

is reported that there are hot springs in the 

lake on the north side n.f Pyramid Island; 

steam is reported to rise .from this area on cold days •. Russell (1885, p. 60) noted several 

hot springs rising from the bottom of the lake 

and along the base of the tufa crags on the 

north side cr the peninsula at The Needles near the north end of Pyramid Lake. No such springs were observed on September 19, 1949. 

There is believed to be no movement o.f 

underground water from Warm Springs and Hinne- mucca Valleys to Pyramid Lake, according to 

D. A. Phoenix, who has studied the area and 

states that the pass from vlarm Springs Valley 

to Pyramid Lake contains fine-grained lake 

sediments. 

Areas o.f phreatophytes along the southern, 

western, and northern shores of Pyramid Lake are relatively minor. On the west shore opposite Anaho Island a patch of salt. cedar covers approximately 1 acre. Approximately 2 miles 

north of Sutcliffe, on the west shore, a ver- dant area o.f not more than 5 acres is evidence 

o.f a small ground-water supply. An irrigated 
111!'16' 

~---------;--;1$' fd' 

Sub-Lacus.tral contoursLahontan beach --~-'-

---------1---1. oo• 

u..-.• nl880' 

1 0 5 Mi:les '-' ---L' ---L' ---L' ~--l---1' 

Figure 4. -- Map of Pyramid Lake, Nev. (after Russell, I. C. 1885. ). 

11 
12 

ranch near the town of Pyramid produces a small 

amount of hay. Along the northwest shore of 

the lake 1 s a narrow band of vegetation a veraging perhaps 100 feet wide and about 1 m1.le 

long. At the north end of the lake, east of 

The Needles, a larger area of about 2 square 

miles is rather sparsely covered with phreatophytes. At an estimated consumptive-use rate 

of 1.0 acre-foot of water per acre, the total 

water consumed probably does not exceed 1,300 

acre-feet per year. As previously mentioned, 

the east shore could not be inspected, but the 

aerial reconnaissance revealed that there is 

very little marginal vegetation along the east 

shore or in the draws leading up into the 

mountains. 

The volume of ground-water inflow cannot be 

precisely evaluated, but it is believed small. 

Movement of ground water through the finegrained Lake Lahontan beds is undoubtedly 

small, but the possibility of substantial 

ground-water flow in the Truckee River channel 

should be investigated. Pumping tests to determine the permeability of these deposits 

would be required. Based on this information 

and on observations of hydraulic gradient in 

test wells, the volume of ground-water flow 

in the Truckee River channel could be computed 

with acceptable accuracy. The field coefficient 

of permeability, as defined by Meinzer (1949, 

p. 454), is conservatively estimated to be 

5,000 gallons per day. The hydraulic gradient 

is assumed to parallel the stream bed, which 

has a gradient of about 8 feet per mile. From a topographic map the average width of the 

channel is estimated to be 1 mile. The thick- ness is assumed to be 100 feet on the basis of a rather common thi clrness of' this magnitude 

in many western areas. Based on these data, 

flow through the aquifer is computed as 4,400 

acre-feet per year. 

An approximate water budget for Pyramid Lake can be calculated. Evaporation is estimated 

by Harding (1935, p. 508) to be about 4 feet 

per year. ~e surface area of the lake is 

approximately 120,000 acres, so that annual 

evaporation is 480,000 acre-feet. There is no surface outflow from the lake and no evidence 

of deep-seepage losses. Annual surface inflow 

from Truckee River averages 36,000 acre-feet 

per year and from the remainder of the Pyramid 

Lake Basin about 4,000 acre-feet. Rainfall on the lake averages about 7 inches per year, or 70,000 acre-feet. Total surface inflow is 

approximately 110,000 acre-feet per y~ar. If 

it is assumed that infrequent short periods 

of storm runoff may be excluded from the com- putations, it is estimated that surface inflow can be measured within 10 percent, or 11,000 

acre-feet, which is 2.3 percent of the annual 

evaporation. If the allowable error in measur- ing the difference between inflow and outflow 

(outflow from Pyramid Lake is zero) is to be 

not more than 5 percent of the evaporation, 

the maximum permissible error in measuring 

inflow to Pyramid Lake must not exceed 24,000 

acre-feet. To meet this requirement, it is 

necessary that the error in measuring groundwater inflow not exceed 13,000 acre-feet. 

Meeting this requirement appears practicable 

in view of the magnitudes of the quantities involved. 

The meteorological conditions at Pyramid 

Lake are complicated by its large size and by 

the surrounding terrain. It is evident that 

surface winds are affected by the topography. 

When the lake w~s visited on September 19, 

1949, several residents of Nixon at the south 

end of the lake agreed that westerly winds 

prevailed throughout the year; and the wind was observed to be westerly on this day. A 

resident of Sutcliffe, on the west side of the 

lake, stated that the wind blew in the direction of the long axis of the lake (northwestsoutheast) during the entire year, which is 

in agreemeRt with the wind direction observed 

at this point on the day of the inspection 

trip. At the north end of Pyramid Lake near The Needles, gusts up to 20 miles per hour were observed several times, indicating the 

possibility of local thermal winds. 

It appears reasonable to assume that local 

land and sea breezes develop during the night 

and day around a lake as large as Pyramid Lake. 

This would occur even if the surrounding terrain were flat. Drainage tongues from the 

adjacent mountains reinforce the land breeze. 

Local vall.ey winds during the day reinforce 

the lak~ breeze, moving inshore and up the 

valleys. The wind structure over the lake, 

both day and night, therefore, consists of a series of tongues around the shore superimposed 

upon and confusing the general flow. 

For the contemplated studies, it is required 

that the stream-line pattern of wind flow over the lake surface be known, and for Pyramid 

Lake this information is lacking. A study of 

the local wind structure is needed; this would 

require the operation of a network of at least 

8 or 10 anemometer stations for at least a year. Without such a study, the proper choice 

of sites for the meteorological installations 

could not be made. Moreover, the size of the 

lake and the probable complexity of its wind 

structure make it likely that a larger number 

of meteorological installations will be needed 

than is now planned for the pilot lake. 

Direct evidence is lacking as to the maxi- mum height of waves to be expected. According 

to Sverdrup (1945, p. 1055), the maximlm 

probable wave height, in feet, in the ocean for very strong w1 nds is 1. 5 ,.JF, when F 1 s 

the fetch in nautical miles. For a fetch of 

18 nautical miles, the maximum height of waves to be expected is 6! feet. Based on his observations in 1882, Russell (1885, p. 62) 

wrote ''Even in summer the gales rise suddenly, without warning, and sweep down upon the lake 

with the fury of a tempest. Sometimes within a few moments the lake is changed from a placid mirror to a sea of frothing billows 

that break on the shore in long lines of foam. 

The suddenness with which the wind changes, and the bleak, inhospitable character of the 

shores, make the navigation of this lake some- what dangerous, even to experienced boatmen." 

A detailed hydrographic survey of Pyramid 

Lake would be required. The only hydrographic 

map available is that prepared by Russell 

(1885, pl. 9) on the basis of soundings made 

in 1882. The maximum depth of water found at 

that time was 361 feet at a point approximately 

8 miles northwest of Anaho Island. Based on area-capacity curves prepared from Russell's 

data, Pyramid Lake now contains approximately 

20,000,000 acre-feet of water; its surface area is approximately 120,000 acres (187 square 

miles); and its average depth 167 feet. 
·llff3o• 

~~~~~~~~~~~·~·~··sub-Lacustral contours--

Lahontan beach --~-'-

3go 

.oo·• 

38° --~---------;45' 

~ 0 5 Miles I I 1 I I I I 

Figure 5. -Map Walker Lake» Nev. (after Russell; I. C., 1885). 

1:3 
14 

As a pilot lake for the water-loss studies, 

Pyramid Lake has both its advantages and disadvantages. Its greatest advantage is that the 

water budget can presumably be determined with 

the. required degree of accuracy. The complex1 ty of the wind structure would require further 

investigation; but probably the most serious 

disadvantage is the large size of the lake. 

Size, by itself, if above the required minimum, 

cannot be considered a disadvantage on theoretical grounds. From a practical viewpoint, however, the large size of Pyramid Lake poses 

many problems, of which one of the more important is the increased instrumentation re- quired. The hydrographic survey would not be a simple task; the inaccessibility of the 

eastern shore complicates the transportation problem. These apparent objections are not 

insurmountable, however, and Pyramid Lake has 

much to recommend it for a study of this 

nature. 

WALKER LAKE, NEVADA 

Walker Lake is located in Miner~l County in 

western Nevada. It lies in one of the several 

closed basins that are remnant~ of Lake Lahontan, a Pleistocene lake of the Great Basin. Walker 

Lake was approximately 23 miles long and varied 

from li to 7 miles in width when surveyed in 

1909. The lake is now about 75 feet lower than 

in 1909, and the area has decreased considerably, particularly at the north end where the slope is flat. (See fig. 5, p. 13.) 

Area-capaci~y curves for Walker Lake have 

been prepared (see fig. 6) based on Russell's 

hydrographic survey ('1885, pl. 15) of the 

+"' 4050 Q) 

Q) 

...... 

. s 

o) 

C) 4000 ~ ~ 

;:I 

til 

~ 

Q) 

i 

...... 

0 

Q) 

'0 

E .-I 

<t:: 3900 

lake in 1882. The surface area in September 1949 was approximately 44,000 acres and the 

contents 4,000,000 acre-feet. Maximum depth 

at this time was approximately 140 feet. 

The accompanying graph (fig. 7) shows how 

lake levels have declined in recent years. The data prior to 1927 are from a compilation by Antevs ( 1938, p. 40). Following a sharp · rise in the 1860s, the lake level declined 

only 14 f&et between 1868 and 1919. Increasing use of water for irrigation during the last 

30 years has greatly diminished the inflow 

from Walker River, and the decline in lake 

level has been greatly accelerated. Only in 

1938 did a substantial rise occur. The elevation of the water surface on September 30,· 

1949, was 4,002.8 teet. 

Walker Lake lies between the Wassuk Range which rises more than 11,000 feet on the west 

and southwest and the Gillis Range which rises 

7,500 feet on the east. Slopes on the west 

side of the lake are much steeper than those on the east. 

The surface supply of Walker Lake is derived 

principally from Walker River. A number of 

ephemeral streams drain directly into Walker 

Lake, mostly on the east slope of the Wassuk 

Range. 

An aerial reconnaissance of the lake on September 14, 1949, revealed with great clarit,y the areas in which ground water is available 

for plant growth. Only a few green patches were seen along the eastern shore and very little green vegetation in the many small 

draws extending into the Gillis Range to the 

Capacity, in millions of acre-feet 

Figure 6, -- Graph showing area and capacity curves for Walker Lake, Nev. 
15 

sooor-------~------~-------r------~------~--------~------~------~------~ 

------ ----- ~,~~ ------- ~~----

-------

--- Arter Antevs 

-- Geologioal Survey reoordl 

Figure 7. -- Graph showing stages of Walker Lake, Nev. 

east. Fairly extensive areas of plant growth 

border the south end of the lake. The draws on the west side of the lake extenditJ.g up into 

the VJassuk Range have green vegetation in 

their upper reaches. At the north end of the 

lake the Walker River delta is marked by ex- tensive areas of phreatophytes, presumably 

supplied from underflow of Walker River and 

from subsurface return flow from irri~tion. 

An approximate annual water budget for 

Walker Lake has been prepared. Based on the 

hydrograph of lake levels (see fig. 7) and the 

area-capacity curves (see fig. 6) based on Russell's survey, the average annual change in 

contents for October l, 19~3, to September 30, 

1949, was 13~,000 acre-feet. This may be in 

error, for the area-capacity curves based on Russell's survey are questionable. When the 

Hawthorne quadrangle was mapped by the Geological Survey, the water surface elevation 

of Walker Lake was found to be 4,078 feet 

(adjustment of 1912). The surface·area of the 

lake as planimetered from this map is 66,000 

acres. Based on Russell's hydrographic survey, 

the surface area at an elevation of 4,078 feet 

is 72,000 acres. Harding (1935, p. 508) used a figure of about 90. square miles, or 57,600, 

acres, at a stage of 4,030 feet. The area from 

Russell's curve corresponding to an elevation 

of 4,030 feet is 5~,000 acres. If ~alker Lake 

is to be used for water-los~ studies, a hydro-_ 

graphic survey will be required, but for the 

purposes of this report, the area-capacity curves based on Russell's survey are assumed 

to be correct. 

Average annual runoff of Walker River at 

Schurz for the water years 19£!4-33 (after 

storage in Topaz and Bridgeport Reservoirs 

began) v1as ~4 ,300 acre-feet. This is believed 

to be of the approxinate general order of 

magnitude for present-day conditions, although possibly less than during the period 1934-49. 

Flow of West ~Jalker River near Coleville, 

Calif., which is believed to be reasonably 

representative of natural runoff in this 

region, during the water years 19£!4-33 averaged a bout 70 percent of flovv during the years 

1934-49. It is difficult to E.::~timate discharge 

of Walker River into Walker Lake after 1933, 

because records of flow at Schurz are lacking. 

The capacity of Topaz Reservoir was increased 

in 1937 and the area of irrigated land has 

been increased since the 19£!4-33 period, thus 

further complicating the situat~on. In the ' 

absence of accurate discharge data for Walker 

River for the entire 19£!4-49 period, however, 

average inflow is assumed to be 24,300 acrefeet, on the basis of records at Schurz for 

the water years 1924-33. 

Other inflow i terns in the water budget include the flow of ephemeral streams, precipitation on the lake surface, and gro1md-water 

inflow. A number of ephemer~1 streams discharge directly into Halker Lake, mostly on the east slope of the Wassuk Range; their 

total contribution to Walker Lake is small, 

probably averaging less than 8,000 acre-feet 

per year, based on estimated runoff of 0.£!5 

inch or less from an area of approximately 

600 squnre miles. Average annual rainfall on the lakes taken as the mean of the Weather 

Bureau records at Schurz and Thorne, is 4.4 

inches. The average surface area of the lake 

during the period 1924-49 was 55,000 acres; 

therefore, average rainfall on the lake sur- face was 20,000 acre-feet. The ground-water 

inflow to the lake can be approximated within 

reasonable limits. Moat ground-water inflow 

is supplied by Walker River. The Walker River 

flood plain below Schurz is 1 to 4 miles wide. 

Assuming a width of 4 miles, a hydraulic 

gradient of 8 feet per mile, a thickness of 

100 feet, and a permea bill ty of 1, 000 gallons 

per day (Meinzer's units), ground-water inflow 

is 3,600 acre-feet per year. The assumed pe~­

ability of 1,000 ~llons per day is pelieved 

to be a conservative upper limit for the Lake 

Lahontan and Walker River fine sediments. 

To summarize, an approximate annual v1ater 

budget is as follows: 

Walker River inflow 

Runoff of ephemeral streams 

Precipitation on lake surface 

Ground-water inflow 

Decrease in contents of Walker Lake 

Total 

Quantity 

(acre-feet) 

24,300 

R,OOO 

£!0,000 

3,600 

133,000 

188,900 

On this basis average annual evaporation is 

computed to be 3.4 feet, which appears to be 

somewhat low. The estimates are admittedly 

only approximate, and have been prepared only 

to illustrate the relative magnitudes of the 

quantities involved. The annual decrease in 

contents is by far the largest item, and can be measured with sufficient precision. Of the 

other items, ground-water inflow is probably 

the most difficult to determine accurately; 

but an error of a hundred percent in measur- ing this item would be almost insignificant 
16 

compared with evaporation. It therefore appears 

that the water ~ldget for Walker Lake can be 

determined· with the required accuracy. 

Meteorological conditions at Walker Lake were no~ investigated. The mountain ranges on each 

side of the lake undoubtedly complicate ~he 

wind-flow pattern. Data on prevailing surface 

winds at Walker Lake are not available,. but 

because of the mountain ranges on each side 

the general flow is probably parallel to the 

long axis of the lake except where locally 

modified by valley breezes on summer days and 

air drainage at night. The effect on the general wind flow of turbulence induced by the 

mountain ranges on each side of the lake is 

not known. 

It appears that a satisfactory water budget can be .obtained at Walker Lake. The decision 

to reject it as a site for the water-loss 

studies was based primarily on its undesirable 

shape and its complicated wind structure re- sulting from the nearby mountain ranges. No 

field investigation was made to provide an estimate of the cost of either the streamgaging stations required or the necessary 

ground-water studies. Although unsuitable for 

the present study, Walker Lake may prove satisfactory for studies to which its elongated 

shape and complicated wind structure are of no consequence. 

BYNUM RESERVOIR, MONTANA 

Bynum Reservoir in north-central Montana is an irri@ation reservoir supplied from Teton 

River and formed by a dam on Alkali Creek in 

T. 26 N., R. 6 w., 4 miles west of the town 

of Bynum, in Teton County. (See fig. e.) It is 

owned by the Teton Cooperative Reservoir Co. 

The reservoirais roughly circular in shape. 

Its surface a~ea as measured on the best 

available map is 4,120 acres (Congress, 1932, 

map 12) and its average depth at full pool is 

approximately 20 feet. It holds 85,000 acre- feet of water at fUll pool elevation of 4,1?5 

feet and 500 acre-feet at 4,130 feet. The 

r&servoir stage on September 24, 1949, was estimated to be 10 feet lower than normal high 

water as shown by well-defined marks on the 

intake tower. Annual diversions to Bynum Re$ervoir average 25,000 acre-feet. 

Built in 1910 and enlarged in 1926, the 

earth-fill dam, including the dike, is approximately 1 mile long, apd its maximum height 

is 60 feet. The westernmost quarter mile of 

the dike is faced with concrete on the upstream 

side. The concrete outlet tunnel discharges into the distribution canal which is lined 

with concrete for a distance of 150 feet below the dam. A gated wasteway from the canal 

discharges into a small natural channel below 

the dam. 

Both the dam and the reservoir are underlain 

by the lower part of the Two Medicine formation, which consists of coarse-bedded gray, 

greenish-gray, red, and yellowish-brown jointed 

shale interbedded with many irregular and 

extremely lenticular sandstqne beds. A few 

siltstone beds and one 6-inch bed of sandy, orange-brown bentonite were observed. In this 

locality the shales break down into tough, highly plastic clays upon remoulding. The 

sandstones are brownish-gray in color and have 

calcareous cement. Most of them are thinly 

Figure 8. -- Map of Bynum Reservoir, Mont. 

and irregularly bedded, but a few are massive. 

Cross bedding is common. Thickness and composition vary greatly. Some beds are made up of coarse uniform grains, others of grains wellgraded from coarse to fine, and still others 

of grains so fine as to be barely discernible 

with the naked eye. The variations in texture 

indicate that permeability probably varies 

greatly with the individual bed. 

The regional dip of the Two Medicine formation is about 120 feet per mile southwestward 

with a strike of about N. 390 W. (Dobbin and 

Erdmann, 1946). In the field, a local dip of 

4° sw. was measured about 100 feet below the 

downstream toe of the dam, 0.23 mile from its 

north end. Strike of these beds was N. 6?0 w. 

On the south shore of the lake about 0.25 

mile from the dam, exposed sandstones dip 

5° SW. and strike N. 40° W. 

Three joint systems are present in the sandstone beds. One ·set is parallel to the bedding. 

A second system, very regularly developed at 

intervals of 0.5 to 3.0 feet, .dips 85° N. with 

strikes ranging from N. ?8° E. to N. 85° E~ A 

third set, roughly perpendicular to the second, 

is poorly developed and many joints deviate 

from the average a few degrees to 30 degrees. 

All the joints are open on the surface from 

1/16 inch to a maximum of 1/2 inch. The dip is 

vertical. 

No faults have been recognized in the immediate vicinity of the reservoir. 

Swamp grass and efflorescent salts along the 

downstream toe indicate that water seeps under 

the dam almost its entire length. There are a number of small flowing seeps, and most of the 

ground in the area below the dam is soggy. The 

discharge of one seep was es tirrla ted to be 0. 04 

second-foot on September ~4, 1949, and the 

leakage through the dam around the outlet 

tunnel was estimated to be 0.5 second-foot. 
Nearly all of the seepage is collected in the 

wasteway, and a• a point ~00 feet below the 

dam, the flow was estimated to be from l to ~ 

second-feet. 

Figure 9 is a sketch showing seepage areas below the dam and a cross section through the 

dam. Although water seeping from the reservoir 

along the bedding planes in the sandstone must 

travel up dip, the statio head is sufficiently high to produce substantial out-flow below the 

dam. 

Seepage when the reservoir is full is un- doubtedly greater than that observed on Sep- tember ~4, 1949, when the reservoir was only partly full due to irri~tion withdrawals. 

At full pool the water seeping below the dam 

is under greater head, and the cross-sectional area is also increased. It does not appear unreasonable to suppose that seepage may then 

amount to 5 second-feet. 

The possibility of deep seepage, or leakage 

through the bottom of the reservoir that might 

not reach the ground surface for a considerable 

distance below the dam, is considered remote 

because of the regional southwesterly dip of 

the Two Medicine formation and the relatively impervious character of the sediments at the 

bottom of the reservoir. Samples of the sediments that were deposita~ when the reservoir was at a higher stage and that are exposed along the shores were found to be composed pre-

~nd 

- ~7 

PLAN OF DAM 

17 

dominantlr of clar and silt. 

Brnum Reservoir is supplied partlr trom 

Teton River. Water is oonvered by canal trom 

Teton River to a point in the Alkali Creek 

basin, trom whence it tlows down a natural 

stream channel to the reservoir. A gravel delta 

approximatelr 600 feet wide and 2,000 feet 

long has been formed where the stream debouches 

from the hills and flows into the reservoir. · There was no evidence of surface flow at the 

delta at the time of the reconnaissance. A few 

small pools of standing water v1ere observed near the edges of the delta. The bottoms of some of the pools were silted. 

At a point approximately ~,000 feet upstream from the shore of the lake the stream channel narrows to 200 feet in width. Here a small 

stream with a flow of from 1 to 2 second-feet 

disappeared into the gravel of the main channel and was not observed to reappear on the 

surface anywhere in the delta. 

The s~eam was followed for a mile upstream 

from this point. Many side gullies were observed, and the sparsely covered hillsides 

show evidence of heavy overland flow and ero- sion. The nearest point to t;he lake at which 

it would be practicable to obtain a record of 

flow in the channel is approximately a mile 

above the mouth, where the stream has been 

cut down to the underlying sandstone. Although heavy rains are infrequent, unmeasured inflow 

N 

500 0 500 Feet 

Water surface 

~·~·_.'-L' ~·~·---------~' 

CROS~ SECTION OF DAM 

1~~0 Feet 

A' 

Figure 9.-- Sketch showing seepage springs below Bynum Dam, Mont. 
18 

between this point and the reservoir might be 

of considerable magnitude. 

Harvey Lake is a small irrigation reservoir loc~ted southeast of Bynum Reservoir (see fig. 

8) and is supplied from the Teton River. Its 

capacity is about 3,000 acre-feet (Congress, 

193D, p. 90). At its nearest point Harvey Lake 

is approximately 1,000 feet from Bynum Reservoir. Its water-surface elevation was estimated 

to be DO to 30 feet higher than that of Bynum 

Reservoir. A dike has been constructed at the 

west end of Harvey Lake to prevent outflow to 

Bynum Reservoir. Alkali and swamp· grass were observed in the 300-foot-wide connecting vall~ 

indicating that there is subsurface flow from 

Harvey Lake to Bynum Reservoir. 

On the northwest side of Bynum Reservoir 

well-defined drainage channels are lacking. 

There is evidence that, in this area, during heavy rains there may be substantial overland 

flow which would be difficult, if not impossible, 

to measure accurately. No attempt has been 

made to evaluate the volume or frequency of 

such flows. 

Annual evaporation from Bynum Reservoir is 

approximately 33 inches, on the basis of an analysis of available records of evaporation 

from pans. Of this amount about 9 inches 

evaporates during the months from April to June, 

the period of maximum inflow, and about 12 

inches during the months of July and August, 

the period of maximum outflow. 

The annual water budget cannot be accurately 

determined because of incomplete information on surface-water inflow and outflow and be- cause of the total lack of data on magnitude of ground-water flow. Neglecting ground-vater 

flow, the annual water budget may be approximated as follows: 

Inflow: 

Diversions into Bynum Reservoir 

Surface inflow from Alkali 

Creek basin 

Rainfall on reservoir surface 

Outflow: 

Evaporation 

Reservoir releases (by difference) " 

Quantity 

(acre-feet) 

25,000 

2,000 

5,600 

32,600 

11,000 

21,600 

It must again be emphasized that ground-water 

inflow, which may be an item of considerable 

magnitude, has not been included. Ground-water 

outflow of necessity has been included in the 

amount shown for reservoir releases. This 

figure was obtained by subtracting the evaporation, which is the only loss that could be 

estimated, from the total of the estimated inflow items. If the inflow items and the reser- voir releases could be measured within 5 percent, which could be attained only at considerable expense for stream-gaging installations 

and operations, the error in the difference, on an annual basis, would be 18 percent of the 

evaporation. This figure would be substantially 

increased if errors in measuring ground-water_ 

flow shoUld be included, which is necessary for a complete determination of the difference 

between inflow and outflow. It is probable 

that, with an extensive collecting system 

below the dam, most of the seepage through 

the dam could be collected and measured. The 

volumes of ground-water inflow entering.the reservoir in the areas adjacent to the supply 

canals and in the Harvey Lake area are unknown. 

B'ynum Reservoir was considered unsuitable 

for the water-loss studies primarily because 

of the uncertainties involved in measuring 

surface- and ground-water inflow and outflow.· 

The rather. short season of high evaporation ~s 

an undesirable but not disqualifying feature. 

In many other respects, however, such as size, 

shape, and freedom from undesirable orographic 

effects, Bynum Reservoir meets the desired 

standards. 

LAKE FRANCES, MONTANA 

Lake Frances is an irrigation reservoir on a small tributary of Dry Fork Marias River in 

north-central Montana, in T. 29 N., R. 5 w., 

in Pondera County. The town o·f Valier is on its north shore. The oval-shaped lake is approx--

imately 4 miles long and 2i miles wide. At 

full pool the water-surface elevation is 

3,816 feet (mean sea level), the surface area is 5,536 acres, and contents are 112,000 acre- feet, according to J. A. Tidyman of The Valier 

Company, Valier, Mont., which owns the reser- voir. 

The reservoir is supplied by a canal known as the C-3 Canal (see fig. 10) which conveys 

water diverted from Birch and Dupuyer Creeks. 

Inflow is greatest during the months of May and June. Tidyman estimates that 50,000 acre- feet passes through the reservoir annually. 

Stor.m runoff from the natural drainage basin 

of approximately 25 square miles occurs infrequently. 

The main dam at the southeast end of the 

lake is constructed of earth, has a concrete core wall (Congress, 1932, p. 8~), and is 700 

feet long and 50 feet high. Dike No. 1, on the northwest side of the lake, is 6,260 feet 

long and 20 feet high. Dike No. ~ on the 

northeast side of the lake is 725 feet long 

anci 4 feet high. 

The extreme southeast end of the reservoir 

and the dam site are underlain by the Virgelle 

sandstone member of the Eagle sandstone, which 

consists of buff to grayish-buff, highly cross- bedded sandstone. It is thinly laminated, finegrained, soft, and friable, with some calcare- ous cement. The remainder of the reservoir is 

underlain by the Two Medicine formation. Contact between the two formations is hidden by 

surficial deposits. The TV1o Medicine formation 

consists of poorly bedded, gray, greenish-gra~ 

red, and yellow clay shales interbedded with 

irregular amounts of lenticular gray-to-buff sandstones and an occasional siltstone. It is 

not exposed in the immediate vicinity of the 

lake but can be seen in the valley of Dupuyer 

Creek. 

In the vicinity of Lake Frances these beds 

dip gently northwestward at 75 to 80 feet per 

mile (Dobbin and Erdmann, 1946). The strike 

of the beds varies from N. 41° E. to N. 33° E. 

along the northern and eastern shores of the 

lake but changes gradually to nearly north on the south side of the lake. No faults have 

been recognized in this immediate vicinity. 
19 

R. 4 W.ll2°10' 

481.,. 

20 1 

30 29 28 27 26 25 30 

z z 0 

M 0 

M 

E-t ~ 31 34 31 

6 

§ :;p 

~c~.s z 

13 18 Cl) 

C"' 

~ 

LAKE 

23 2 .. 1-9 211 22 23 

480 

15 ~~~~--~~----~--------~--------~--------~--------~------~---------L--~L-~ ll2°15'R. 5 W. 

1 1 

a 0 1 Mile 

Figure 10. -- Map of Lake Frances, Mont. 

Except for the previously mentioned small area at the lake outlet, bedrock ie covered 

by an unknown thickness of glacia.l debris and 

alluvium throughout the lake basin and adjacent areas. Little is known of the character 

of these surficial deposits because the landis farmed and no good exposures were found. 

Most of the inflow to Lake Frances is con- veyed by the C-3 Canal which v~s inspected 

at the road crossing approximately half a mile above the l~ke. Its design capacity is 

900 cubic feet per second, but on September 

24, 1949, the flow was estimated to be 70 

cubic feet per second. The canal banks at this 

point are of soil underlain by a comparatively 

impermeable gravel-clay mixture. Along a 300-

foot reach the canal had cut through this 

material, exposing from 0.5 to 3.0 feet of 

clean coarse highly permeable sandy gravels 

of fluvial origin. Water entering these 

gravels may be discharged into the lake. A 

precise determination of the amount of w~ter 

reaching the lake as canal underflow would be 

difficult. 

Annual inflow from the natural drainage 

basin of approximately 25 square miles is between 0.5 and 1.0 inch, according to Langbein 

{1949, pl. 1). Using the higher figure, annua1 

inflow is approximately 1,300 acre-feet. Some 

storm runoff would be included in the meas~red 

flow of C-3 Canal, but the determination of 

inflow from the area immediately adjacent to 

the lake might prove difficult. 

It is probable that some return flow from 

irrigation may enter the reservoir along the 

southwest shore. According to Tidyman, an area of about 300 acres is irrigated.from the 

C-1 Canal, usually only once each year. A 

total of 200 acre-feet of water is applied. 

"'i'b.e return flow.probably does not exceed 100 

acre-feet. 

Annual precipitation at Valier, according 

to u. s. Weather Bureau records (Commerce, 

1948, p. 254), averages 12.65 inches, which 

amounts to 5,800 acre-feet at full-reservoir 

level. Precipitation during May and June, the 

two wettest months, averages 1.83 and 3.00 

inches, respectively. 

Surface outflow from the lake is discharged 

through the dam into a canal. Because of a diversion structure bal£ a. mile below the 

dam, precise measurements of outflow might 

prove difficult. It is also possible to re- lease water from Lake Frances into the C 

Canal at a point near the northeast end of 

dike No. 1. The floor of the outlet structure 

is at 3,800 feet elevation, or 16 feet below 

full-pool elevation. 
20 

Subsurface outflow from the reservoir is 

apparently restricted to the area near the 

main dam and to the area near dike No. 1. A 

collecting gallery intercepts part or the 

seepage through the dam. This flow, about 0.5 

cubic foot per second, is pumped to the Conrad 

municipal water-supply system. Near the dam, 

Virgelle sandstone is exposed along the shore on both sides of the lake for a distance of 

about 2,000 feet above the dam. It is also ex- posed along the Dry Fork Marias River tributary below the dam in sec. 24, T. 29 N., 

R. 5 W. The beds dip in a northwest~rly direction at low angles. The following determinations were made: 

No. Location Strike ~ 

1 Lake shore, swtswi sec. 14, T. 25 N., R. 5 w. N. 440 w. so sw. 

2 Dry Fork Marias River 

trLbutary, SE!NW! sec. 24, T. 29 N., R. 5 w. N. 58° E. 50 NW. 

3 Dry Fork Marias River 

tributary, SEfNWt sec. 24, T. 29 N. , R • 5 W. N. 75° E. 30 NW. 

4 Road cut, Et corner sec. 23, T. 29 N., R. 5 w. N. 30° w. 70 sw. 

Determinations l and 4 are probably on cross laminations, but determinations 2 and 3 agree· 

roughly with the regional dip and are believed 

to represent true bedding of the sandstone. 

Permeability normal to the bedding of the 

sandstone is probably compa:rati. vely low, but 

permeability along the bedding and orcas- bedding surfaces is fairly high. This is demonstrated by a series of seeps that discharge 

along the north wall of the valley (called the 

P Canal) and that are supplied from the L 

Canal. The seepage water is under a head of 

about 14 feet and travels along paths varying from 25 to 200 feet in length. Discharge is 

entirely along the bedding and cross-bedding 

surfaces. The seepage in this area on September 24, 1949, was estimated to be about 3 

gallons per minute. Without doubt seepage is 

also taking place through these sandstones 

around both abutments of the dam. A well into 

rock at the farmhouse near the northwest corner of sec. 24, T. 29 N., R. 5 w., intercepts part of this flow. The water level in 

this well is reported to fluctuate with the 

stage of the reservoir. The quantity of seepage water may not be large, but it wo.uld be 

difficult to measure accura.tely. 

There is considerable seepage along dike 

No. 1. This seepage water, together with seepage from the C Canal,collects in a pond at 

the s-f corner sec. 31, T. 30 N., R. 5 w. Seepage appears to be confined to the contact between the dike and its foundation and to the 

lower part of the dike. It might be possible 

to separate the amount of seepage through the 

dam from amount of the seepage through the 

canal banks by measurements of the seepage 

when the canal flow is zero. 

The remainder of the lake basin appears to 

be comparatively watertight despite the fact 

that it is floored by strata of the Two Medicine formation that contai~many permeable 

sandstone members. _Seepage is prevented by a blanket of surficial deposita, no doubt 

assisted to some extent by silting of the 

reservoir. The impermeability of the soil artd 

underlying surficial deposits is demonstrated 

by the tact that on September 24, 1949, water was standing in a pond about a ctuarter or a 

mile. east or the lake, in the SWt sec. 1:3, T .• 29 N., R. 5 w., at an elevation approximately 

35 teet higher than maximum lake level. This 

pond was formed in June 1948 by surface t'unott 

following unusually heavy rains. Subsequent loss of water has been at a sufficiently low 

rate to be a·ccounted for by evaporation,. indicating that seepage losses have been. negligible. 

Annual evaporation from Lake Frances as based on an analysis of available records of evapo- ration from pans is about 33 inches. At· full 

pool, annual evaporation is 1~,200 acre-feet. 

An approximate annual water budget, assUming 

Tidyman's estimate of 50,000 acre-feet passing through the reservoir to be outflow, is as follows: 

Outflow; Rese~voir releases 

Evaporation 

Seepage 

Total outflow 

Inflow: 

Rainfall on lake 

Return flow from irrigation 

C-3 Canal (by difference) 

Total inflow 

Quantity 

(a ere-feet) 

50,000 

15,200 

1,000 

66,200 

5,800 

100 

~~:~gg 

The figure for seepage loss is admittedly only a rough estimate and has been included 

only to indicate its approximate relative 

magnitude. The water budget indicates that inflow and outflow are approximately four. times as great as evaporation. If the measurement errors are considered to be normally distributed, and both inflow and outflow can be . measured within 5 percent, the error in the 

difference between the two quanti ties .1,s about 

4,000 acre,;.,feet,-or more than 25 percent-of the annual evaporation. · · 

The water budget is further complicated by 

the configuration of the lake, which. mak;es 

accurate determinations of mean stage some- what difficult. The lower end of Lake Frances 

terminates in a rather narrow neck. The ampli- tudes of seiches caused by the preva~ling 

westerly winds are probably magnified very 

much in the area near the dam. The assumption 

of a plane-water surface cannot be made~ and a network of precise stage gages would be re- quired. 

Meteorological condi tiona at Lake Frances 

appear to be favorable. The terrain is fairly 

flat except along the south Shore where hills 

rise to a height of 100 to 200 feet above the 

lake at a distance of a mile or so away. The 

wind structure apparently is not complicated 

by orographic effects. The prevailing winds are westerly. Summer humidity is low. 

According to Tidyman, the lake is frozen 

from appr·oxima tely December 5 to April 15 

each year. Average January temperature _is 

16.6° F..,.and average July temperature is 65.4° F., 

according to Weather Bureau records (Agriculture, 1941, p. 917). Year-round observations of evaporation appear impractical. 
Lake Frances was rejected as a possible site 

for the water-loss studies because of the 

difficulty in obtatning a water budget of the 

required degree of accuracy. In many other re~pects, such as shape, size, depth, and 

freedom from orographic effects, the lake 

meets the requirements. The long period of 

ice cover in the winter is an undesirable but 

not disqualifying feature. 

LAKE ABERT, OREGON 

Lake Abert, oval-shaped and approximately 

10 miles long and 3 miles wide, is in a closed 

basin about 30 miles north of the town of 

Lakeview in south-central Oregon. Waring (1908, 

p. 38) made a geologic and hydrologic recon- naissance of the area in 1906 and determined 

the surface area of Lake Abert to be 60 square 

miles at that time. It has less than half that area at present and is much shallower than 

it used to be. No soundings were made on the 

day the reconnaissance was made, September 20, 

1949, but the depth at the present time is 

reported by R. A. Work(in a personal communication relaying information from Philip Smith) 

to be about 3 feet. ~e lake is shallower now than it has been for several years, although 

it was lower in 1931 and 1934. Antevs (1938, 

p. 18) reported that it was dry in August 19~4 except for a few small pools fed by 

springs and a small area on the east side 

supplied by Poison Creek. According to Waring 

( 1908, p. 38), ''The northern end of the Abert 

Lake basin is so nearly level that it is said 

that a strong south wind often forces the 

water back nearly 2 miles over the alkaline 

flat***·" 

Lake Abert lies upon a huge block of Miocene 

basalt that dips to the east. It is confined on its eastern side by the Abert Rim, a fault 

scarp that towers more than 2,000 feet above 

the lake and is said to be one of the highest 

in the United States. Russell (1884, p. 447) 

described the Lake Abert fault as follows: 

''The grand cliffs that present an impassable 

barrier along the eastern shore of Abert Lake 

expose the broken edges of the strata on the 

heaved side of a fault; while the thrown side 

underlies the lake basin and forms the gently sloping western shore." A geologic section in an approximately east-west direction through 

Lake Abert is shown in figure 11. 

Accorning to Waring (1908), ~The basalt is a dark gray, fine-grained, rather vesicular 

rock,approximately parallel partings, usually 

at intervals of only a few feet, mark the 

division between successive flows, but in some places much thicker beds are exposed. Fissures 

nearly-perpendicular to the parting planes 

break the basalt into blocks, which by trans- verse fracturing are reduced to smaller and 

21 

smaller fragments, forming the characteristic 

talus slopes of the cliffs." 

Chewaucan ~iver enters the south end of 

Lake Abert, after flowing through the Chewaucan 

Marsh, and constitutes almost the entire sur- face-water inflow into the lake. The average 

annual flnw of Chewaucan River above Conn 

ditch, near Paisley, Oreg., is approximately 

95,000 acre-feet. However, not all the flow 

reaches Lake Abert as water is diverted from 

the Chewaucan River for irrigation in the 

Paisley area; and although the return flow 

from irrigation eventually finds its way 

through the Narrows to Lake Abert, the con- sumptive use may amount to more than half of 

the flow in some years. On the average, sur- face inflow to Lake Abert is roughly estimated 

to be 60,000 acre-feet, which is less than 

the evaporetion from the lake. Flow of Chewaucan 

River into Lake Abert is not now measured and 

it is by no means certain that it can be 

measured within 5 percent, for the slope in 

the water surface in the reach below the dam 

and fal~s is small, and may be affected by 

strong winds or changes in lake levels. Runoff 

from spring rains in the ares directly tributary to the lake would be dif"ficult to measure accurately. No studies have been made of the 

frequency of these storms, but the total 

volume of runoff is small compared with the 

flow of Ohewaucan River. 

Many small fresh-water springs were seen on the east side of Lake Abert between the highway and the lake. The flow of some springs was so small as to produce only a marshy area having small pools of standing water. Many 

springs were discharging water directly to 

the lake. The volume of flow was small;. discharge of most springs was estimated to be 

less than 0.05 cubic foot per second. The 

temperature of the water in the seeps along the eastern shore was from 790 to 79° F. on September 20, 1949. The temperature of both 

the air and the water in the lake was 65° F. 

at that time. The temperature of the water in a seep near the northeastern corner of -the 

lake was also 65° F. 

At the north end of the lake are fairly ex- tensive areas of marshland on which hay is 

grown. Irrigation water is supplied from numerous seeps. There is no simple way to meaaure the return flow from the irrigated areas. Waring (1908, p. 51) mentions a strong 

spring at the ranch house, but this spring v..a.s not looked for on the reconnaissance 

September 20, 1949. 

Along the western shore the seepage area was estimated to be at least three times as great in extent as that along the eastern 

shore. The flow of several springs was estimated to be 0.5 cubic foot per second or more. 

Figure 11. -- Cross section through Chewaucan Marsh and Lake Abert, Oreg. 

(after Waring, 1908, plate 10 ) . 
22 

The seeps and springs along the western shore 

according to Waring (1909, p. 51), are evidently fed by waters that accumulate on the 

slopes between Lake Abert and Chewaucan Marsh, 

seep down the dip of the basalt, and reach the 

surface at the lake shor~ (See fig. 11.) He 

did not mention the springs or seeps along the eastern shore. but it seems likely that 

they are supplied from the same source. As 

the water travels down dip under the lake it 

may be prevented from discharging into the 

lake bottom by the relatively impervious sediments that have been deposited over the lake 

bed and can find its way to the Burface only 

after it reaches the fault zone on the eastern 

aide of the lake. 

Annual evaporation from Lake Abert is estimated to be approximately 4 feet, based on an analysis of available records of evaporation 

from pans. Of the 4-foot total, approximately £.3 feet occurs during the 4-month per~od 

June to September. 

An annual water budget for Lake Abert is 

difficult to estimate because of the lack of 

data but may be approximated as follows: 

Evaporation 

Inflow: 

Surface water 

Ground water (by difference) 

Quantity 

(acre-f'eet) 

77,000 

60,000 

17,000 

Outflow is considered to be zero. Ground-water 

inflow was assumed to be that amount which, 

when added to the surface inflow, is required 

to maintain the lake at its present level. 

Both surface- and ground-water inflow are known to vary widely from year to year. The 

lake is now much smaller than in times past, 

indicating that inflow has generally been leas 

than evaporation during recent years. On an annual basis, 5 percent of the estimated 

evaporation is 3,850 acre-feet--possible error in measuring ground-water inflow alone exceeds 

this amount. The possible error•in measuring surface-water inflow may also exceed 5 percent of the evaporation. The elope of the water 

surface of Chewaucan River in the'reach upstream from the lake is flat and may be 

affected by the level of Lake Abert. 

The volume of ground-water inflow during summer months, when flow of Chewaucan River 

is depleted by irrigation, may amount to a substantial porti.on of the total inflow. Obtaining continuous records of the flow of the 

many springe would be an expensive undertaking. 

The possibility of springe in the lake bed, 

although remote, cannot be ignored. The meas- urement of total inflow to Lake Abert within 

the allowable limite of accuracy was deemed 

impracticable. 

Annual precipitation at Valley Falla, at the 

southern end of Lake Abert, averages 11.10 

inches. Rainfall during July, August, and 

September is light, but the remainder is welldistributed throughout the year. Humidity is 

normally low in central Oregon during the 

summer, and westerly winds predominate. Average 

temperature at Valley Falls is 30.4° F. in 

January and 66.70 F. in July (Agriculture, 1941, p. 1075). 

The effect or topography upon meteorological conditions at Lake Abert was not studied in 

detail. The great fault scarp on the eastern 

side or the lake unquestionably artects the 

wind structure over the lake. Westerly winds 

predominate in the large scale circulation, 

but southerly surface winds prevail at the 

southern end of the lake at Valley Falls, as might be expected. 

Because or the impracticability of determining the water·budget with the required degree of accuracy, Lake Abert was considered 

unsuitable as a pilot lake for the water-lose 

study. Meteorological conditions are not favorable, and the lake is shallower than is 

desirable, but the decision to reject Lake 

Abert was based upon the lack of an accurate 

water budget. 

BIG SAGE RESERVOIR, CALIFORNIA 

Big Sage Reservoir l$ an irrigation reser- voir in northeastern California, 10 miles· 

northwest of Alturas in Modoc County. (See 

fig. 12.) The reservoir is irregularly shaped, and when full covers an area of 5,570 acres and stores 77,000 acre-feet of water. It was constructed in 1921 by damming Rattlesnake 

Creek, a Pit River tributary that drains a broad, nearly flat, upland plateau about 5,000 

feet above sea level. The drainage area is · 107 square miles, according to Ingerson (1932) •. 

The plateau on which Big Sage Reservoir lies 

is known as the Gardena (Russell, 1928, p. 400) or the Devils Gardens (Z&nder, 1933, pp. 24-

27). According to Russell, the Gardens plateau is about 2,000 square miles in area, and has a cap of smooth lava which he named the Warner 

basalt. The basalt.is a vesicular volcanic 

flow of surprising extent and uniformity. It 

is approximately 30 feet thick at the south 

rim of the Gardens as exposed in the bluff 

north of the Alturas-Canby road (U. s. Highway 299). Near the south end of Goose Lake, at the 

east edge of the Gardens, it is at least 225 

feet thick. 

Russell's Warner basalt is underlain by his 

Cedarville series, a group of andesitic rocks 

about 7,500 feet thick. They are composed of 

·tuff beds, agglomerate, and lava, all andesitic 

in character, with about 5 percent of interbedded sedimentary rocks of nonvolcanic origin. Where obse~ved tn the bluffs north of Highway 299 near the dirt road leading to Big Sage Reservoir, the Warner basalt ~s underlain by a dense, white tuff bed which had the appear- ance of a ''chalk rock". This tuff bed is very 

extensive, according to Russell. 

Big Sage Dam was built in Rattlesnake Creek 

canyon, which has been eroded 40 to 50 feet 

below the surface of the Warner basalt. It is 

not known whether the stream had cut through the basalt into the tuffaceous beds beneath. 

Photographs made during the excavation for 

the dam suggest that the white tuff beds are exposed in the cut. T. R. Simpson of the 

California State Division of Water Resources, 

Sacramento, Calif., who was present when the 

excavation was made, states that the white 

tuff bed was exposed. The cut-off trench, 

which was excavated to a depth of 10 feet below the base of the dam, is therefore believed 

to penetrate the fine-grained white tuff. 
23 

R. 11 E. R. 12 E. 

21 22 19 

28 27 

BIG SAGE 

33 35 I 36 

z i ~ RESERVOIR ~ ~ ~ 

~ ~ 

i z C'l) C'l) 

~ ~ 

~ 4 .~ 

10 11 12 

R. 11 E. R. 12 E. 

2 0 10 Miles L' ----''-L...--'---l...._.L.~! 

Figure 12. -- Map of Big Sage Reservoir, <;alif. 

Russell's Warner basalt has a coarse columnar 

jointing and is vesicular. The vesicles are commonly net interconnected and do not cause the rock to be permeable, but the columnar 

jointing may. Ingerson (1932, P• 4) states 

that the basin is relatively impervious because 

of a surface accumulation of ~ementing ash 

and adobe soils. No ash was observed in the area visited on June 12, 1949, but it is believed that the underlying tuffaceous beds are relatively impermeable and provide an essentially watertight foundation. According 

to Ingerson, Supervising Hydraulic Engineer, California State Division of Water Resources, 

Sacramento, Calif., colloidal material remains 

in suspension in the reservoir indefinitely, regardless of.whether the water is disturbed or quiescent, and the reservoir bed has been 

virtually sealed. 

If the basalt were sufficiently permeable 

to absorb and yield large quantities of water, 

springs should appear Where the base of the 

basalt is exposed. No springs were seen along the bluffs north of the Alturas-Canby highway. According to Silas B. Kelley, President, Hot 

Springs Valley Irri~tion District, Alturas, 

Calif., prior .to the .construction of the dam 

in 1921 Rattlesnake Creek ceased to flow in 

July or August, and no springs were known for 

several miles downstream from the dam site. 

However, the·Alturas reconnaissance sheet 

(1892), which was based in part on information 

obtained by.the Wheeler Survey, snows several 

springs about 3 miles downstream from the dam 

site. They are apparently at a somewhat higher elevation than the reservoir, although elevations shown on the Alturas reconnaissance sheet are admittedly not precise. Simpson reports 
24 

that a spring in the reservoir site supplied 

the Woods ranch with sufficient water to irrigate 40 to 50 acres of meadow during the sum- mer. It is presumed that this spring discharged 

water stored in the fractured basalt. Reports 

suggest _that its flow was not greater than 

approximately 1 cubic foot per second. Inger- son estimates that the flow of small spripgs 

in the reservoir area totaled possibly 4 or 5 cubic feet per second. 

There appears to be little seepage through 

and around the dam. A small seepage a~ea ~rked 

by green grass and ~tanding water was noted on the left bank 200 feet below the dam and 

20 to 25 feet above the stream. There was no visible discharge. An inspection trip was made on foot for a distance of about 3,500 

feet downstream from the dam. A small amount 

of side seepage is evident. A strip of green 

grass about 2,000 feet long and 40 feet in 

average width borders each bank of Rattlesnake 

Creek. Up to a height of 3 to 5 feet above 

the stream bed, cattle hoofprints stand full 

of water, but no running water was observed. 

If the grassy s~rips, whose total area is 

approximately 4 acres, are supplied by seepage through or around the dam, as is likely, the 

volume of water thus consumed is probably about 10 acre-feet per year. However, seepage losses are apparently very small for, according · to Ingerson, when the outle.t valve in the dam 

is closed, the creek is dry below the dam. 

About 2,000 feet downstream from the dam a grove of poplars lines the ,right bank of the 

creek for a quarter of a mtle. These trees 

antedate the construction of the dam, and pre- sumably are supplied from water stored in the 

basalt and resting on the tighter tuffs beneath. 

The reservoir was inspected by boat. The 

surrounding terrain is quite flat, and the 

point at which Rattlesnake Creek enters the 

reservoir could not be located readily, so that ground-water conditions along the creek were not i~vestigated. Seepage along the shoreline was noted at only one point, where three 

springs seeping from an amphitheatre-like area wer~ discharging into the reservoir at a rate 

estimated to be 0.05 cubic foot per second. 

Total ground-water discharge from the reser- voir is believed .negligible. Ground-water inflow cannot be measured precisely, but"is 

certainly small. The surrounding terrain is 

quite flat, and storage of water in the reser- voir has substantially decreased the hydraulic 

gradient causing the flow of the spring or springs known to have existed in the reservoir area. Although the quantities involved are quite small in comparison w1 th evapo :n1 ti on during the summer, further investigation to 

determine the approximate spring discharge is 

warranted. 

Flow of Rattlesnake Creek, according to 

Ingerson, averages not more than 2 cubic feet 

per second during May and June, and is prac- tically zero during July, August, and Septemben Records of contents in and outflow from the 

redervoir have been made available by v. R. 

Scammon, Watermaster, California State Division of Water Resources, Alturas, Calif. 

Based on records for the years 1940-48, an approximate water budget for April-September 

has been calculated. 

Inflow~: 

Rattlesnake Creek 

Rainfall on reservoir surface 

Estimated ground-water inflow 

Total 

Outflow: 

Reservoir releases 

Quantity 

(acre-feet) 

240 

1,200 

300 

1,'740 

8,350 

The average decrease in reservoir contents 

during April-September for the years 1940-48 was 16,100 acre-feet. Average evaporation was (1,?40- 8,350 +16,100), or 9,490 acre-feet. 

The reservoir surface area averaged 4,100 

acre-feet. Estimated average evaporation for 

this 5-month period was therefore 28 inches over the reservoir surface. 

The three major items in the water budget are the rainfall on the reservoir surface, 

change in reservoir contents, and reservoir 

releases. Rainfall on the reservoir surface 

doubtlessly can be measured with sufficient 

precision. Although existing area-capacity tables are quite adequate for the needs of 

the irrigation district, a hydrographic re- survey of the reservoir would be required, so that changes in reservoir contents could be 

measured with the degree of accuracy necessary for the water-loss studies. Reservoir releases are at present measured by means of an outletvalve rating. A continuous record of outflow can be obtained below the dam, but the con- struction of an artificial control, possibly a Parshall flume, would be required. It is 

believed that the requirement that the error in the volumetric de.termination of evaporation shall not exceed 5 percent can be met. 

The wind structure over Big Sage Reservoir 

is not complicated by orographic effects. The 

reservoir is on a high plateau, and the slopes are gentle. Average January temperature at 

Alturas is 2?.3° F. and average July temperature is 6?.3° F. Rainfall averages 12.60 

inches annually (Agriculture, 1941, p. ~85). 

Water temperature in the reservoir, measured on June 12, 1949, near the intake towe.r at a depth of approximately 6 inches, was ?9° F. 

The temperature of the water measured at the 

discharge end of the outflow pipe was 61° F. 

A water samp~e was taken, and the results of 

the analysis made by the Geological Survey are as follows: 

Ion 

Iron (Fe) 

Calcium (Ca) 

Magnesium (Mg) Sodium (Na), potasstum (K) 

Carbonate (C03) 

Bicarbonate (HC03) 

Sulfate ( S04) Chloride {CI) 

Nitrate ( N03) 

Borate (B03J Dissolved solids 

pH 

Parts per 

million 

0.03 

1'7 

9.5 

13 

16 

88 

8 

2 

.1 

.1 

109 

8.5 

There are no recent maps of the reservoir area. Older maps show the reservoir to be 

quite regular in shape. Aerial photographs made September 20, 1948, when the reservoir 

stage was approximately 10 feet below full 
pool, show the reservoir outline to be quite irregular at that stage, as 1.llustrated il'l 

figure 1::::, which was prepared from an aerial 

photograph. 

When the reservoir was inspected by boat on June 1~, 1949, the stage was approx1matel7 l 

root higher than on September ~0, 1948, when 

the aerial photographs were made. Rooky shoals were noted bJ the inspecting part7. Many long reaches of shore slope so gently that extensive areas may be quite shallow. At 4,100 acres, 

the average surface area during the period 

1940-48, a change in stage of l foot results 

in a change in surface area of ·nearlJ 5 percent. Because the reservoir area was not 

cleared of trees when the dam was built, many trunks are still standing. 

Big Sage Reservoir was rejected as a possible site for the water-loss studies chiefly be- cause or its irregular shape. A tairly regular shape is essential tor a test ot certain 

theoretically derived equations relating evap- oration to observed meteorological elements. 

It appears, however, that a water budget ot 

the required accuracy can be obtained. 

ELSINORE LAKB, CALIFORNIA 

Elsinore Lake, a natural lake in southern 

California, lies about ~0 miles south of Riverside, Calif., in Riverside County. It is 

supplied infrequently by San Jacinto River, 

and only during or after years of exceptional~ 

heavy rainfall has it overflowed into Temescal 

Creek, its natural outlet. Schanck (1919, p. 71) has prepared an excellent acc~unt of tile 

early history or Elsinore Lake. There has been no outflow since 1917 (Water-Supply Paper 1091). 

The lake is quite re~r in shape and is 

abOut 5 miles long and lt miles wide. According 

to Harding (.19t:2), the elevation of the Temesoal 

Creek outlet is 1,260 feet, and at this stase 

the surface are~ is about 6,000 acres and the 

contents 1~,000 acre-teet. The stage is now much lower. On June 7, 1949, the elevation or the 1ake surface was 1,232.7 feet. It was re- ported by William areyette, a local resident, 

that the maximum depth or water in the lake 

is approximately 9 feet. Much or the lake is 

less than 5 feet deep. According to Harding (19:::?7, p. 328) the lake hs.s gone dry in periods or deficient rainfall. -

-The geology and ground-water condi tiona in 

this area have been described by Waring (1919, 

pp. 69-79). The basin in the vicinity of 

Elsinore Lake is underlain by Recent and 

Pleistocene alluvial deposits and Tertiary sedi~entary rocks. The alluvial deposits con- tain ground water, and probably at least some of the Tertiary rocks are sufficiently per- meable to contain ground water. The thickness 

of these deposits is not known accurately, but Waring (1919, p. 76) gives the log of an artesian well near the northwest end of Lake 

Elsinore that penetrated at least 254 feet of 

material that was probably unconsolidated. 

A well of the South Elsinore Mutual water Co. near the southwest end or the lake penetrates 

497 feet of apparently unconsolidated deposits. Wells in the alluvial deposits flowed in 

earlier years, and Waring mentions the exist- ence of hot sulfureted springs in the town of 

Elsinore on the northeast lake shore. D. R. 

Crane, civil engineer in Elsinore, reports 

that in January 194'7 the water level in several 

1rrif§lt1on wella neaz• the northweat end or the 

lake was 20 to 50 teet below the lake level 

at that time. It is not known whether the hot 

springs now flow or whether the flow 11 de• 

creasing. Apparentl7 no wella in the vicinit7 

flow at the present time, the head preaumabl7 having been reduced b)' pumpina tor irzotsation. 

Although the water level in relativelr deep wells may be below lake level, it seema posaibll that shallow water may stand above and c:SN.i~ 

toward the lake even at preaent. Discharse ot 

hot springs may alao enter the lake. 

A sample ot water was taken just below the 

lake surface on June 7, 1949, near the pier 

at the Aloha Beach Club at Elsinore. The water 

temperature close to the surtace was 900 p. 

in the afternoon ot this day. The sample was analyzed by the Geological Survet and tbe re- sults are as follows: 

Ion 

Iron (Fe) 

Calcium (Ca) Magnesium ( Mg) Sodium (Na), potassium (K) 

Carbonate (C03) 

Bicarbonate (HCOs) 

Sulfate ( S04 ) 

Chloride (CI) 

Sora te ( BO:i). 

Dissolved solids 

pH 

Parta per million 

0.01 

'7.3 

52 

3,370 

'782 

1,400 

496 

3,250 

24 

8,880 

9.4 

The anemist making the analysis also reported the. presence ot hJdrosen sulfide in the sample. 

The ground-water conditions around Lake 

llsinore are complicated and would have to be 

studied carefully before an7 accurate determination could be made as to Whether or not . there is substantial seepage ot ground water 

into or away trom the .lake, and before an esti•ate could be made ot the quantities involved. It would be difficult to determine· 

accurately the amounts o.f seepage loss or aain to or from ground water in the basin. 

There might also be a discharge of warm ground 

water from suballuvial springs whose presence might not be detected at all. 

Elsinore Lake has been used for many studies or evaporation.· It has generally been assumed 

that there.is no ground-water inflow or outw 

flow. Barding (1927, p. 328) states, "The 

lake bed appea~s to be impervious. It is 

stated that no inflow from adjacent ground 

water was apparent when the lake was dry. There is no indication of seepage from the 

lake, adjacent wells with water below lake 

level showing no indication of mixture with 

the salty water or the lake.~ Orie wonders, 

however, if at those times when the lake was reported dry there may not have been marshy areas where ground-wa~er inflow evaporated as it reached the surface. Schanck (1919, p. 71) 

mentions that the original Mexican name tor 

the lake was "Laguna Grande", and that a traveler in 1810 noted that it was but little more than a swamp about a mile long. It is 

entirely possible that ground-.Nater inflow is 

negligible compared with evaporation since 

magnitude or the evaporation indica ted by records at Elsinore Lake appears to be consistent with that at other places. 
26 

The determination of the amounts of groundwater inflow and outflow, if any, would re- quire an exhaustive study of the entire groundwater situation. Such a study might prove to 

be a monumental task because conditions are aamittedly quite complex, and there is no positive assurance that results of the required 

degree of accuracy could be obtained at a reasonable coat. Because of the uncertainty in measuring ground-water flow, and because 

the lake is very shallow, Elsinore Lake was given no further consideration. 

LAKE MATHEWS, CALIFORNIA 

Lake Mathews, formed by Cajalco Dam, is located about 10 miles southwest of Riverside, 

in Riverside County, Calif. The dam was com- pleted in 1938 by the Metropolitan Water 

District of Southern California as a unit in 

the distribution of water from -the Colorado 

River. The capacity of Lake Mathews is 

107,000 acre-feet, and its surface'area at 

spillway level is 2,020 acres. 

It is supplied principally from the Los 

Angeles aqueduct through the Val Verde tunnel. 

Present operating practice is to maintain 

contents at approxima~ely 85,000 to 100,000 

acre-feet. According to c. c. Elder, hydrographic engineer, Metropolitan Water District 

of Southern California, Los Angeles, Calif., 

annual inflow and outflow may total 100,000 

acre-feet. In the dry months, monthly inflow 

and outflow may amount to 20,000 acre-feet 

and 15,000 acre-feet, respectively. Evapora- tion is estimated from pan records at about 

8,000 acre-feet per year, with a maximum of 

1,100 to 1,200 acre-feet per month. Thus errors of 1 percent in measuring monthly inflow and 

outflow may amount to about one-third of the 

evaporation during summer months. Although inflow and outflow are now measured with a pre- cision quite adequate for operational purposes, 

it appears impracticable to measure the difference between inflow and outflow with the 

accuracy required for the water-loss study. 

In order to meet the requirement that the error in the difference between monthly inflow and 

outflow shall not exceed 5 percent. of the 

monthly evaporation during the summer months 

it would be necessary that the error in meas- uring inflow and outflow not exceed about 0.2 

percent, which appears impracticable. 

The reservoir area is underlain by igneous rocks ranging from granite through granodiorite 

and gabbro, and a ·small body of tonalite. 

Seepage losses from the reservoir are not large 

and can be accurately measured. A detailed 

study of ground-water conditions would be re- quired to demonstrate conclusively the possible 

magnitude of ground-water inflow from the 

Gavilan hills to the south. 

Meteorological conditions at Lake Mathews are generally favorable. The surrounding 

terrain slopes gently, and the wind structure 

is believed to be uncomplicated by mechanically 

induced turbulence. Annual rainfall averages about 10 inches. 

Lake Mathews was rejected as a site for the 

water-loss studies because of the impracticability of measuring inflow and outflow volumes 

with the required accuracy. In many other 

respects Lake Mathews is quite suitable, but 

the volumes of inflow and outflow are so large 

that the possible error in the difference between these two quantities is greatly magnified. 

SALTON SEA, CALIFORNIA 

Salton Sea lies in a closed basin in southeastern California. In middle Tertiary time 

the Gulf of California extended much farther 

north than at present and included what is , now the Salton Sea, according to Blake (1914, 

pp. 2-3). Later, as the continental land sur- face rose, the increased silt load of the · Colorado River formed an i:nnnense delta. The 

head of the Gulf became an inland salt sea, 

fed at intervals by flood waters of the Colorado. 

Eventually, however, desiccation took place. 

Prior to 1905, large quantities of water 

reached Salton Sea only infrequently, according to Cory (1913, p. 1228). Its recent history 

has been described in detail by Mendenhall 

(1909, pp. 21-24), Brown (1923, pp. 3-12), and 

many others, with special reference to the 

Colorado River floods of 1905-06. During this 

period the floodwaters of Colorado River 

poured into the Salton Sea, transforming it 

from an old dry lake, or playa, to the present 

large inland sea. 

The elevation of the water surface of Salton sea in 1949 was approximately 240 feet below sea level. (See fig. 13.) The stage has varied 

little since 1944. At elevation -240, the 

surface area of Salton Sea is 210,000 acre$ 

and its contents 4,033,000 acre-feet. 

The major source of surface-water supply of 

Salton Sea is drainage from irrigated areas in the Imperial Valley in the United States 

and Mexico. The drainage enters Salton Seain 

the channels of New and Alamo Rivers. Records 

of the Imperial· Irrisation District show that 

for the 5-year period 1944-48 the average 

annual discharge into Salton Sea was 1,0?9,000 

acre-feet. Whitewater River and San Felipe 

Creek flow directly into Salton Sea, but con- tribute substantial volumes of runoff only 

after infrequent storms. Peak discharge of 

Whitewater River at Point Happy, near Indio, 

during the January 1916 flood was 10,160 c~bic 

feet per second, according to Tai t ( 1917, p. 9 ). · 

The volume of ground--water inflow in the 

Coachella Valley area is difficult, if not 

impossible, to estimate. According to Mendenhall {1909, p. 37), "there is a continuous . slow movement of these subterranean waters 

beneath the Indio region toward the southeast, 

but the water does not escape to the gulf. 

Much the greater part of the subsurface percolation probably reaches the surface eventually 

in the vicinity of the Salton Sea, and before 

the inflow of the Colorado it escaped into 

the air by evaporation." The saturated sands 

average more than 1,000 feet in thickness in an area of at least 400 square miles, Mendenhall estimated. Since the time of Mendenhall's 

report (1909), the ground-water·resources of 

the Coachella Valley have been extensively 

developed, and much of the water formerly 

reaching the Salton Sea area is now used for 

irrigation. 

Ground-water inflow is not limited to the 

Coachella Valley area. According to Brown (1923, 

p. 66), "Nearly every permanent or intermittent 
.... -190 

~ 

; 

1-210 

~ 

j 

a; 

~ -230 

.s 

~ 

-

f--

J 

f 

J ll) 

~' 

~ 

~ 

I I I I I I I I I i I 

s ~ 

~- ..... -- ._!.-

"-- ....... ~ r/' ~ ~ 

I I I I I I I I I I i I I I I I I I I I I I I 0 ll) 0 ll) 0 ll) 

N N M M ..,. ..,. 

Figure 13. -- Graph showing stages of Salton Sea, Calif. 

stream becomes interrupted in its lower portion as it nears the desert, because of 

gradual changes in the character of its bed 

and the increasing amount of porous gravel 

along its course. Without exception; all the 

streams either sink completely into the desert 

soil or flow only in certain stretches before 

reaching their ultimate destination in the 

Salton Basin or other desert basins." 

Estimates of evaporation from Salton Sea 

vary within rather wide limits. Annual evaporation from three screened pans in the vicinity of Salton Sea averaged 93.7 to 114.9 inches over a 2-year period, according to A. C. Bowen 

of the u. s. Soil Conservation Service, who 

states that a coefficient of 0.98 is applicable 

to this type of pan. Other evaporation-pan 

records obtained in this area indicate annual 

evaporation to be approximately 90 inches. 

LaRue (1916, p. 142) estimated annual evaporation from Salton Sea to be 5.8 feet, but his 

estimate appears low, for he did not take 

ground-water inflow into account. Normal evaporation from a Class-A pan, as taken from the 

map prepared by Horton (1943, p. 750, fig. 2), 

is about 115 inches per year. Using a coefficient of 0.7, equivalent reservoir evaporation is 80 inches. Mean annual evaporation in the 

Salton Sea area, as taken from the map prepared by Meyer (1942, map 4), 1s approximately 

85 inches per year. 

For the purpose of estiEating the possible 

magnitude of unmeasured surface- and groundwater inflow into Salton Sea, annual evaporation is taken as 80 inches. During 1944-48, 

the surface area of Salton Sea remained fairly 

constant at about 200,000 acres .. Average 

annual evaporation is therefore estimated to 

be 1,330,000 acre-feet. Measured inflow during 

this period averaged 1,079,000 acre-feet per 

year. Since the contents of the sea did not 

change substantially during this period, un- measured inflow apparently averaged 250,000 

acre-feet per year. However, a computation of 

this nature is subject to gross errors, for 

an error of 6 inches in the estimated evaporation would result in an error of 100,000 

acre-feet in the estimate of unmeasured inflow. 

The fact remains, however, that since the 

stage of Salton Sea has remained relatively 

constant during the last few years, evaporation must approximately equal inflow. For the 

purposes of this study it is required that 

the maximum allowable error in measuring evaporation by volumetric means must not ex- ceed 5 percent of the actual evaporation. It 

appears that a measurement of thlsaccuracy 

for Salton Sea is impracticable. Most of the 

surface inflow is now measured by the Imperial 

Irrigation District. Even if the infrequent 

periods of storm runoff are excluded from the 

accounting, an extensive network of stream 

gaging stations would be required merely to 

demonstrate conclusively the occurrence or nonoccurrence of storm runoff. Although each 

gaging station could be of extremely simple 

construction, many would be required, and the 

total cost would be high. 

The problem of measuring ground-water inflow 

is immensely more difficult. Considerable 

field study would be required to select proper 

si tea for a network of ob·serva tion wells. 

Pumping tests would be necessary for permeability determinations. Continuous records 

of water-level elevations would be required. 

Admittedly a costly undertaking, it has the more serious drawback that there is no posi- tive assurance that results would be of the 

necessary high degree of accuracy. 

The large size of Salton Sea poses some problems in connection with the meteorological 

observations to be made as a part of the 

water-losE study. The number of meteorological 

observation stations deemed adequate for a lake of say 10 square miles surface area is 

inadequate for a water surface as large as Sal ton Sea. Preliminary field studies of the 

areal variations in meteorological elements 
might be needed before a decision could be 

reached as to the number and location or observation stations. A hydrographic survey of 

Salton Sea would be required. With modern 

equipment the task would be.essentially routine 

in nature, despite its magnitude. Another 

problem complicated by the size of Salton Sea 

is the precise determination of stage. Seiche 

amplitudes may be fairly high. In addition to a number of gages along the shores, it would 

appear essential that some method be devised 

for the precise measurement of stages at 

points on the lake in order to obtain a true 

picture of the surface, whether flat or tilted, or warped by wind action. 

The decision to eliminate Salton Sea from 

further consideration as a site for the waterloss investigations was, therefore, based 

primarily on the belief that it would be 

impracticable to determine the water budget 

with the required degree of accuracy. The 

problems arising from the great size of Salton 

Sea are not considered unsurmountable. 

OTHER RESERVOIRS 

Many other reservoirs and lakes were suggested for consideration as possible sites 

for the water-loss study. They were rejected 

because of failure to meet the spec.ifica tiona 

in one or more respects. Brief comments on many of the suggested lakes have been prepared 

to indicate the principal reason for eliminating them from further consideration. Many of 

i;he:•J) reservqirs and lakes may also fail to 

meet the specifLcations in respects other than 

those mentioned, but detailed studies were not made if preliminary investigations indicated that the lake was unsuitable because of 

size, shape, or the impracticability of determining an accurate water budget. 

Arizona 

Green Reservoir.~-Abandoned. 

Mormo~Lake.--Dry in 1947; little water in 

1949. Very shallow, saucer-shaped basin; small 

changes in stage result in large changes in 

surface area. Roosevelt ~eservoir.--Long, narrow; prevailing winds at right angles to long axis; large 

fluctuation in stage. 

California 

~-Vista Lake.--Dry in 1949 and will not 

contain water again until a fairly large flood occurs in Kern River. 

Butte Lake.--For.merly a shallow reservoir 

but now abandoned. 

Calaveras Reservoir.--Small; surface area slightly more than 2 square miles; inflow and 

outflow are large compared with evaporation. 

Clear Lake (Cache Creek).--Ground-water move- ment into or out of Quaternary deposits may 

be substantial and would be difficult to meas- ure accurately; irregular shape; mountains on three sides. 

Clear Lake (Lost River).--Irregular shape; 

islands and shoals divide lake into two basins; 

adjacent swamp is larger than lake. 

Copper Basin Reservoir.--Small; surface area less than 1 square mile. 

Crystal Spring Reservoir.--Small; surface area slightly more than 2 square miles; i.nflow and 

outflow large compared with evaporation. 

Eagle Lake.--very irregular shape; large 

ground-water outflow. 

Bast !ark Rettervoir. --Small; surface area less 

than square miles at full pool; large irrigation withdrawals. 

Hatfield Reservoir.--Contains no water ~ther 

than infrequent waste from Colorado River 

Aqueduct. . Honey Lake.--Irregular shape; dry in September 

194§. 

Horse Lake.--Dry in 1949; very irregular shape. 

Kern Lake.--Generally dry or nearly so. Lake Almanor.--Mountain reservoir; extremely 

irregular shape. Lake Arrowhead.--Small; surface area slightly more than 1 square mile. 

Lake Henshaw.--Subsurface inflow during late summer months may amount to 25 percent of the 

evaporation. 

Lake Levitt.-•Small; large irrigation withdrawals. 

Lake Pillsbury.--Irregular shape; inflow and 

outflow large in comparison with evaporation. 

Lake Tahoe.--Large; surface area 193 square miles. -Inflow and outflow large compared with 

evaporation; inflow difficult to measure. Mesquite Lake.--Dry in 1949. 

Mono Lake.--Many springs in lake bottom. 

Morris Rese~yoir.--Canyon reservoi~. 

Mountain Meadows Reservoir.--Shallow; average depth about 4 feet when reservoir is full. 

OWens Lake.-~Shallow; average depth less than 

10 feet; mountain ranges rise 6,000-7,000 feet 

above lake on east and west. 

Prado Reservoir.--Flood-control reservoir; 

normally empty. 

Salinas Reservoir.--canyon reservoir. 

Shasta Reservoir.--Very irregular shape; canyon res.ervoir; probable errors in measuring inflow and outflow large compared with evaporation. 

Stony Gorge Reservoir.--Canyon reservoir. 

Tinnemaha Reservoir.--small; inflow and outflow large in comparison with evaporation. · 

Colorado 

Green Mountain Lake.-~Inflow and outflow very 

large compared with evaporation. · John Martin ReserVoir.--Irrigation withdrawals 

occasionally reduce contents to zero. 

Idaho 

Bear Lake.--Impracticable to determine surfaceand gr~und-wate~ inflow and outflow with ~equired accuracy; large shallow areas with 

water-using vegetation. Blackfoot Marsh Reseryoir.~-Irregular shape; 

subsurface losses difficult to determine. 

Coeur d'Alene Lake.--Extremely irregular shape. 

Crane Creek Reservoir.--Long, narrow; inflow 

and outflow large compared with evaporation. 

Deer Flat Reservoir.--Large and variable subsurface losses. 

Grays Lake.--Large shallow areas; considerable 

portion of lake area covered with tules. 

Hayden Lake.--Reparted to have large subsurface 

losses, particularly at high stages; surrounding terrain mountainous. 

Henrys Lake.--Ground-water inflow and outflow 

difficult to determine _accurately. 

Island Park Reservoir.--Large changes in bank 

storage. 

Magic Reservoir. --About 8 miles long and up to 

2 miles wide with long axis approximately at 

right angles to prevailing winds; shore line 

irregular. 

Mud Lake.--Substantial ground-water inflow, difficuit to measure. 
Missouri 

Wappapello Reservoir.--Long, narrow; very 

irregular shore line; humid climate; inflowoutflow difference cannot be measured with 

sufficient accuracy. 

Montana 

Deadmans Basin.--Small; surface area less than 

3 square miles. 

Hebgen Res.ervoi~.--Irregular shape; mountain 

reservoir. · Pishkun Reservoir.--Small; surface area less 

than 3 square miles. 

Ruby Reseryoir.--Small; surface a·rea less 

than 1 square mile. 

Swan Lake.--Long, narrow; mountain lake. 

Tongue River Reservoir.--Long, narrow; irregu- lar shore line. 

Willow Creek Reservoir (Sun River).--Small; 

less than 3 square miles. 

Nebraska 

Johnson Reservoi~.--Inflow and outflow very large in comparison with evaporation. McConaughy Lake.--Considerable bank storage; long, narrow; irre.gular shore line; prevailing summer winds across long axis. 

Sutherland Reservoir.--Substantial subsurface 

losses. 

Nevada 

Carson Lake.--Large subsurface return flow 

from irrisation; large area of water-using vegetation. 

Lahontan Reservoir.--Long, narrow; irregular shape. 

Lake Tahoe.--See list of California lakes and 

reservoirs. 

Rye Patch Reservoir.--Long, narrow; irre~lar 

shore line. 

Sn9w Water Lake.--Supplied mainly by subsurface flow; dry much of the time. 

Washoe L&ke.--Large subsurface inflow; very shallow; large areas of wa tar-using vegetation~ 

New Mexico 

Alamogordo Reservoir.--Long, narrow; irregular 

shore line; prevailing summer winds normal to 

long axis of lake. 

Blue Water Lake.--Irregular shore line; broken 

terrain; subsurface losses reported to be of 

considerable magnitude. Caballo Reservoir.--Long,. narrow; rugged 

terrain; irregular shore line; subsurface inflow from Black Range on west. 

Conchas Reservoir.--Two arms nearly at right angle~; shore line very irregular. El Vado Reservoir. --Long, narrow; irregular shore line. 

Elephant Butte Reservoir.--Long, narrow; 

mountains on east side; subsurface inflow from 

Black Range on west; transpiration losses large. Hondo Reservoir.--Seldom contains water. 

Lake McMillan.--Used for temporary detention 

only. 

North Dakota 

Devils Lake.--Magnitude of surface- and groundwater inflow and outflow uncertain and difficult to measure; irregular shore lipe with 

large bays and arms., which may be separated from main body of water during dry years. 

29 

Oklahoma 

Great Salt Plains Reservoir.--Inflow and outflow very large compared with evapo~tion and 

cannot be measured accurately. 

Oregon 

Agency Lake.--Large swampy areas bordering lake. 

Agency vai!ey Re~ervoir.--Small; surface area at full ~ool less·than 3 square miles; large withdrawals for irrigation during summer months. 

Antelope Reservoir.--Large irrigation withdrawals during summer months; reported dry in late summer of 1949. 

Cottage Grove Reservoir.--small; surface area less than 2 square miles. · Crater Lake.--Substantial portion of inflow 

believed lost by seepage; surrounded by escarp.-

ment from 500 to 2,000 feet high. 

Drew Reservoir.--Long, narrow; very shallow on west side; apparently considerable groundwater inflow. 

Fern Ri~ge Reservoir.--very shallow; considerable marginal vegetation; large drawdown in 

winter; may be considerable bank storage in 

terrace gravels along east shore. 

Gerber Reservoir.--very irregular shape; too 

small in September 1949 because of large irrigation withdrawals. 

Malheur Lake.--very shallow, if not dry; occasional outflow to Harney Lake difficult 

to measure accurately. Owyhee Reservoir.--Long, narrow; canyon reser- voir. 

Summer Lake.--Practically dry in September 194~ 

Upper Klamath Lake.-~Considerable marginal vegetation; shallow; irregular shape. Warmsprings Reservoir.--Large irrigation withdrawals in late summer; contents only about 

7,000 acre-feet in August 1949. 

Wickiup Reservoir.--Substantial subsurface 

inflow and outflow. 

Texas 

Barker Reservoir.--Detention reservoir with no provision for permanent storage. Bridgeport Reservoir.--Very irregular shape. Brownwood Reservoir.--Irregular shape; inflow 

and outflow large compared with evaporation. 

Buchanan Reservoir.--Irregular shape; inflow 

and outflow large compared with evaporation. 

Buffalo Lake.--Small; surface area .about 3 

square miles when reservoir contents are 18,150 acre-feet, but contents usually much 

less than this. 

Eagle Moun~ain Reservoir.--Long, narrow; 

irregular'shore line. 

Fort Phantom Hill Reservoir.--Irregular shape; small; surface area less than 4 square miles on September 30, 1949. 

Lake Abilene.--Small; surface area less than 

1 square mile.· 

Lake Dallas.--Inflow and outflow large com- pared with evaporation. Lake Kemp.--Extremely irregular shape. Lake Kickapoo.--Long, narrow; inflow occasionally very large in comparison ~ith evaporation. 

Lake Kirby.--Small; surface area less than 1 

square mile~ 

Lake Travis.--very irregular shape. Possum Kingdom Reservoir.--Very irregular shape. 

Red Bluff Eeservoir.--Monthly changes in 

contents very large in comparison with evaporation. 

San Angelo Reser~£ir.--Not yet completed in 

spring 1950. 
30 

Utah 

Bear Lake.--see Idaho list of lakes and reser- voirs. 

Deer Creek Reservoir.--Canyon reservoir. 

Hyrum R~servoir.--Small; surface area less 

than 1 square mile. 

Midview Reservoir.--Small; surface area less 

than i" ·square mile. 

Salt Lake.--Usually dry. Sevie~-~ridge Reservoir.--Long, narrow; has 

been dry at times. 

Sevier ~ke.--Usually contains little, if any, 

water. 

Strawberry Re~ervoir.--Inflow and outflow 

large compared with evaporation, which is re- ported to be low; elevation ?,500 feet. 

Utah Lake.--Shallow; average depth less than 

10 feet. Subsurface inflow difficult to determine. 

Washington 

'BlueJ Lenore, and Soap Lakes.--A chain of 

elongate lakes in the lower and south half of 

the Grand Coulee; shape and topographic setting 

unsatisfactory. 

Moses Lake.--Irregular shape. 

Wyoming 

Jackson Lake.--Irregular shape; many tributary 

streams. 

Lake Hattie.--Seldom contains any large quantity of water. 

Wyoming Devel£P.ment No. 2.--Long, narrow reservoir; inflow and outflow large compared 

with evaporation. 

Wyoming D~velopment No. 3.--Irregular shape; 

inflow and outflow large compared with evaporation. 

REPERBNCES CITED 

American Society of Civil Engineers, 1949, 

Hydrology Handbook, ASCE Manual of Engineering Practice No. 28. 

Anderson, E. R., Anderson, L. J., and Marciano, 

J, J., 1950, A review of evaporation theory and development of instrumentation: u. s. 

Navy Electronics Lab. Rept. No. 159 (free on application to U. s. Geol. Survey, Washington ~5, D. C.). 

Antevs, E. v., 1938, Rainfall and tree growth 

in the Great Basin: Carnegie Inst. Washington Pub. No. 469. 

Blake, w. P., 1914, The Cahuilla Basin and 

Desert of the Colorado, in MacDougal, D. T., 

The Salton Sea: Carnegie Inst. Washington 

Pub. No. 193. 

Brown, J. s., 1923, The Salton Sea region, 

Calif.: u. s. Geol. Survey Water-Supply 

Paper 497. 

Congressional documents: ?2d Congress, 1st 

sess., H. Doc. 191, 1932. 

Cory, H. T., 1913, Irrigati~n and river con- trol in the Colorado River delta: Am. Soc. 

Civ. Eng. Trans., val. ?6. 

Dobbin, c. E., and Erdmann, c. E., 1946, 

Structure contour map of the Montana plains, 

u. S. Geol. Rurvey geophysical investigations map •. 

Erdnlann, c. E., Davis, N. A., Beer, Wm., and 

Nordquist, J, W., 1946, Preliminary structure contour map of the Cut Bank.-- West 

Kevin border districts, u. s. Geol. Survey 

geophysical investigations map. 

Harding, s. T., 1922, Report on San Jacinto 

River Hydrographic Investigation: California 

Div. of Water Rights. 

Harding, s. T., 192?, Evaporation on Reclamation projects (discussion): Am. Soc. Civ. 

Eng. Trans., val. 90. 

Harding, s. T., 1935, Evaporation from large 

water surfaces based on records in California 

and Nevada: Am. Geophys. Union Trans. , pt. 2. 

Horton, R. E., 1943, Evaporation maps of the 

United States: Am. Geophys. Union Trans., 

pt. 2. 

Ingerson, I. M., 1932, Report on supervision 

of diversions from Pit River and Rattlesnake 

Creek in Hot Springs Valley, Modoc County, 

Calif., 1931 season: State of California 

Div. of Water Resources Rept. (mimeographed~ 

Jones, J. c., 1925, Quaternary climates: Geologic history of Lake Lahontan, Carnegie 

Inst. washington Pub. No. 352. 

Langbein, w. B., 1949, Annual runoff in the 

United States: u. s. Geol. Survey Circ. 52. 

LaRue, E. c., 1916, Colorado River and its 

utilization:. U. S. Geol. Survey Water-Supply 

Paper 395. 

Meinzer, o. E., Ground w~ter, in Physics of 

the Earth, Nat. Research Council,_ McGrawHill, 1942, reprinted by Dover Publications, 

Inc., 1949. 

Mendenhall, w. C., 1909, Ground waters of the 

Indio region, Calif.: u. S. Geol. Survey 

Water-Supply Paper 225. 

Meyer, A· F., 1942, Evaporation from lakes 

and reservoirs: Minnesota Resources Comm. 

Russell, I. c., 1884, A geological reconnais- sance in southern Oregon: U. s. Geol. Surv8,1 

4th Ann. Rept. 

Russell, I. c., 18J5, Geological history of 

Lake Lahontan: u. s. Geol. B~rvey Mon. 11. 

Russt:·ll, R. J., 1928, Basin range structure 

and stratigraphy of the Warner Range, northeastern California: California Univ., Dept. 

Geol. Sci~ Bull. val. 17. 

Schanck, F. R., 1919, in Waring, G. A., Ground 

water in the San Jacinto and Temecula Ba- . sins, Calif.: U. S. Geol. Survey Hater-Supply 

Paper 429. 

Sverdrup, H. U., 1945, Oceanography, in Handbook for Meteorologists, 1st ed., McGrawHill. 

Tait, c. E., 191?, Preliminary report on con- servation and ~ontrol of flood water in 

Coachella Valley, Ca~if.: 5th Bienn. Rept., 

California Dept. Eng ••. Appendix D. 
U. S. Dept. Agr., 1941, Climate and Man: 1941 

Yearbook of Agriculture. 

u. s. Dept. Commerce, Weather Bur., 1948, Climatological data, vol. 35, No. 13. 

u. s. Geol. Survey, 1949, Surface-water supply of the United States, '1947, Water-Supply Paper 1091. 

31 

Waring, G. A., 190A, Geology and water resources of a portion of south-central Oregon: u. s. 

Geol. Survey Water-Supply Paper 220. 

Waring, G. A. , 1919, Ground water in the San 

Jacinto and T~meoula Basins, Calif.: U. s. Geol~ Survey Water-Supply Paper 429. 

Zander, Gordon, 1933, Pit River investigation: State of California Div. of Hater Resources, 

Bull. 4:J.. 

Interior--0upl1oat1n& Seotion, 11a1Jhin&ton, D. C.J 3711