Prepared in cooperation with the Oregon Water Resources Department

Ground-Water Hydrology of the Upper Klamath Basin,

Oregon and California

U.S. Department of the Interior

U.S. Geological Survey

Scientific Investigations Report 2007–5050

Version 1.1, April 2010
Cover: Left, Klamath Marsh at Military Crossing, looking west, (photograph by Marshall Gannett); upper right, 

Sprague River Valley from Knot Tableland, looking southeast (photograph by Kenneth Lite); lower right, Sheepy 

Ridge (on the left) and the Tule Lake subbasin from Lava Beds National Monument, looking north (photograph 

by Marshall Gannett).
Ground-Water Hydrology of the Upper 

Klamath Basin, Oregon and California

By Marshall W. Gannett, Kenneth E. Lite Jr., Jonathan L. La Marche, 

Bruce J. Fisher, and Danial J. Polette

Prepared in cooperation with the Oregon Water Resources Department

Scientific Investigations Report 2007–5050

U.S. Department of the Interior

U.S. Geological Survey

Version 1.1, April 2010
U.S. Department of the Interior

DIRK KEMPTHORNE, Secretary

U.S. Geological Survey

Mark D. Myers, Director

U.S. Geological Survey, Reston, Virginia: 2007

Revised: 2010

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Although this report is in the public domain, permission must be secured from the individual copyright owners to 

reproduce any copyrighted materials contained within this report.

Suggested citation:

Gannett, M.W., Lite, K.E. Jr., La Marche, J.L., Fisher, B.J., and Polette, D.J., 2007, Ground-water hydrology of the 

upper Klamath Basin, Oregon and California: U.S. Geological Survey Scientific Investigations Report 2007-5050, 84 p.
iii

Contents

Abstract...........................................................................................................................................................1

Introduction.....................................................................................................................................................2

Study Area..............................................................................................................................................2

Purpose and Scope ..............................................................................................................................8

Geologic Framework .....................................................................................................................................8

Geologic Controls on Ground-Water Flow........................................................................................8

General Geology....................................................................................................................................8

Hydrogeologic Units...........................................................................................................................10

Effects of Geologic Structure ...........................................................................................................12

Hydraulic Characteristics of Regional Hydrogeologic Units.......................................................12

Aquifer Tests...............................................................................................................................13

Well-Yield Tests..........................................................................................................................16

Ground-Water Hydrology ...........................................................................................................................17

Hydrologic Budget..............................................................................................................................18

Ground-Water Recharge ...................................................................................................................20

Ground-Water Discharge to Streams..............................................................................................22

Geographic Distribution of Ground-Water Discharge to Streams ....................................23

Temporal Fluctuations in Ground-Water Discharge to Streams........................................23

Ground-Water Discharge to Streams by Subbasin..............................................................23

Sprague River Subbasin—Geographic Distribution of Ground-Water 

Discharge .............................................................................................................23

Sprague River Subbasin—Temporal Variations in Ground-Water 

Discharge .............................................................................................................26

Williamson River Subbasin—Geographic Distribution of Ground-Water

Discharge .............................................................................................................27

Williamson River Subbasin—Temporal Variations in Ground-Water 

Discharge .............................................................................................................28

Upper Klamath Lake Subbasin—Geographic Distribution of Ground-Water

Discharge .............................................................................................................29

Upper Klamath Lake Subbasin—Temporal Variations in Ground-Water

Discharge .............................................................................................................31

Lost River Subbasin—Geographic Distribution of Ground-Water Discharge.......32

Lost River Subbasin—Temporal Variations in Ground-Water Discharge..............33

Klamath River Subbasin—Geographic Distribution of Ground-Water 

Discharge .............................................................................................................34

Klamath River Subbasin—Temporal Variations in Ground-Water Discharge........35

Summary of Geographic and Temporal Variations of Ground-Water Discharge 

to Streams .....................................................................................................................37
iv

Ground-Water Hydrology—Continued

Ground-Water Discharge to Wells...................................................................................................38

Methods.......................................................................................................................................38

Ground-Water Pumpage for Public-Supply Use...................................................................38

Ground-Water Pumping for Irrigation ....................................................................................38

Recent Increases in the Rate of Ground-Water Pumping ..................................................41

Hydraulic Head Distribution and Ground-Water Flow Directions ..............................................42

Sprague River Subbasin ...........................................................................................................46

Williamson River Subbasin ......................................................................................................46

Upper Klamath Lake Subbasin ................................................................................................46

Upper Lost River Subbasin.......................................................................................................47

Klamath Valley............................................................................................................................47

Butte Valley/Red Rock Valley Area.........................................................................................47

Lower Klamath Lake Subbasin ................................................................................................48

Tule Lake Subbasin....................................................................................................................48

Klamath Canyon Area ...............................................................................................................48

Fluctuations in Hydraulic Head ........................................................................................................48

Climate-Induced Fluctuations..................................................................................................50

Pumping-Induced Fluctuations ...............................................................................................51

Response to Canal Leakage.....................................................................................................51

Response to Lake Stage ...........................................................................................................53

Long-Term Water-Table Fluctuations .....................................................................................53

Fluctuations in Hydraulic Head in Response to Recent Increases in 

Ground-Water Pumping ..............................................................................................59

Summary and Discussion...........................................................................................................................64

Acknowledgments.......................................................................................................................................65

References Cited..........................................................................................................................................66

Appendix A. Landsat Analysis Methods .................................................................................................71

Contents—Continued
v

Figures

Figure 1. Map showing the upper Klamath Basin, Oregon and California, and major

geographic features ........................................................................ 3

Figure 2. Map showing distribution of precipitation in the upper Klamath Basin, Oregon

and California, and mean monthly precipitation at selected precipitation

measurement stations ..................................................................... 5

Figure 3. Map showing irrigated areas in the Bureau of Reclamation Klamath Project,

Oregon and California ..................................................................... 7

Figure 4. Map showing hydrogeologic units of the upper Klamath Basin, Oregon and

California .................................................................................... 11

Figure 5. Graph showing cumulative distribution of transmissivity values estimated from

specific-capacity tests for wells producing from Quaternary sediment, Tertiary

sedimentary rock, and Tertiary volcanic rock in the upper Klamath Basin,

Oregon and California ..................................................................... 17

Figure 6. Schematic representation of sources of ground-water recharge, flow paths,

and mechanisms of ground-water discharge in the upper Klamath Basin,

Oregon and California ..................................................................... 20

Figure 7. Map showing principal areas of ground-water discharge to streams and major

springs in the upper Klamath Basin, Oregon and California, and selected

stream-gaging stations ..................................................................... 24

Figure 8. Graph showing annual precipitation at Crater Lake National Park, Oregon, and

the cumulative departure from average precipitation from 1932 to 2005 ............ 25

Figure 9. Graph showing september mean discharge of the Sprague River near

Chiloquin, Oregon (USGS gaging station number 11501000), and the cumulative

departure from average precipitation at Crater Lake, Oregon ........................ 27

Figure 10. Graph showing monthly mean discharge and September mean discharge of

the Williamson River below Sheep Creek near Lenz, Oregon (USGS gaging

station number 11491400), and the cumulative departure from average

precipitation at Crater Lake, Oregon ...................................................... 28

Figure 11. Graph showing relation between the September mean discharge of the

Williamson River below Sheep Creek near Lenz, Oregon (USGS gaging station

number 11491400), and the cumulative departure from average precipitation at

Crater Lake, Oregon ........................................................................ 29

Figure 12. Graph showing discharge measurements of Spring Creek, estimated

ground-water discharge to the lower Williamson River between Kirk and

Chiloquin, and cumulative departure from average precipitation at Crater Lake,

Oregon ....................................................................................... 30

Figure 13. Graph showing monthly mean discharge and January to March mean

discharge of Annie Spring near Crater Lake, Oregon (USGS gaging station

number 11503000), and the cumulative departure from average precipitation at

Crater Lake ................................................................................. 31
vi

Figures—Continued

Figure 14. Graph showing discharge of the Wood River as measured or estimated at

various sites, and the cumulative departure from average precipitation at

Crater Lake, Oregon ........................................................................ 32

Figure 15. Graph showing discharge of Bonanza Springs and cumulative departure from

average precipitation at Crater Lake, Oregon .......................................... 34

Figure 16. Graph showing August mean gains in flow (a proxy for ground-water

discharge) between Keno (USGS gaging station number 11509500) and the

John C. Boyle power plant (11510700), estimates of inflow by PacifiCorp, and

the cumulative departure from average precipitation at Crater Lake, Oregon ...... 36

Figure 17. Graph showing September to November mean gains in flow (a proxy for

ground-water discharge) between the John C. Boyle power plant (USGS

station number 11510700) and Iron Gate Dam (11516530), and the cumulative

departure from average precipitation at Crater Lake, Oregon ........................ 37

Figure 18. Map showing areas irrigated with ground water in the upper Klamath Basin,

Oregon and California, during the 2000 water year, and areas with primary

ground-water irrigation rights in Oregon ................................................ 40

Figure 19. Graph showing growth in total acreage with ground-water irrigation rights

(primary and supplemental) in the upper Klamath Basin in Oregon through

2005 .......................................................................................... 41

Figure 20. Maps showing distribution of ground-water pumping for the Bureau of

Reclamation pilot water bank during water years 2003 and 2004, upper

Klamath Basin, Oregon and California ................................................... 43

Figure 21. Map showing generalized water-level contours and approximate directions

of regional ground-water flow in the upper Klamath Basin, Oregon and

California .................................................................................... 45

Figure 22. Map showing selected observation wells in the upper Klamath Basin, Oregon

and California .............................................................................. 49

Figure 23. Graph showing water-level fluctuations in well 30S/07E-06AAA near Bear

Creek northeast of Crater Lake, Oregon ................................................ 50

Figure 24. Graph showing water-level fluctuations in well 36S/14E-25BCB near Bly and

the cumulative departure from average precipitation at Crater Lake, Oregon ...... 51

Figure 25. Graph showing water-level fluctuations in well 35S/12E-26DCD north of

Beatty, Oregon .............................................................................. 52

Figure 26. Graph showing water-level fluctuations in well 40S/12E-32CDB northwest of

Malin, Oregon .............................................................................. 52

Figure 27. Graph showing water-level fluctuations in well 40S/09E-28ADB on the

southwest side of the Klamath Hills, Oregon, and monthly discharge in the

nearby North Canal ........................................................................ 53

Figure 28. Graph showing water-level fluctuations in shallow and deep water-bearing

zones in double-completion well 39S/12E-35ABB near Lorella, Oregon ............ 54

Figure 29. Graph showing water-level fluctuations in shallow and deep water-bearing

zones in double-completion well 39S/12E-35ABB near Lorella, Oregon, with

time scale expanded to show effects of nearby ground-water pumping ............ 54
vii

Tables

Table 1. Generalized hydrogeologic units in the upper Klamath Basin, Oregon and

California .................................................................................... 12

Table 2. Summary of selected aquifer tests, upper Klamath Basin, Oregon and 

California .................................................................................... 14

Table 3. Estimates of major hydrologic budget elements of the upper Klamath Basin,

Oregon and California ..................................................................... 19

Table 4. Estimated ground-water pumping for irrigation in the upper Klamath Basin,

Oregon and California, during water year 2000 .......................................... 39

Table 5. Ground-water pumping for the Bureau of Reclamation pilot water bank 

and ground-water acquisition program, upper Klamath Basin, Oregon and 

California .................................................................................... 42

Table 6. Estimated ground-water discharge to principal stream reaches in the upper

Klamath Basin, Oregon and California ................................................... 72

Figure 30. Graph showing water-level fluctuations in well 35S/06E-10ACC near Pelican

Butte and stage in Upper Klamath Lake, Oregon ....................................... 55

Figure 31. Graph showing water-level fluctuations in well 38S/09E-17CBC in the north

part of Klamath Falls and stage in Upper Klamath Lake, Oregon ..................... 55

Figure 32. Graphs showing water-level fluctuations in wells 36S/14E-25BCB near Bly,

39S/11E-20AAD near Bonanza, and 41S/14E-08CCA in the southern Langell

Valley, Oregon .............................................................................. 56

Figure 33. Graphs showing water-level fluctuations in wells 36S/10E-14ACC and

36S/11E-20DCA in the Sprague River Valley, Oregon.................................... 57

Figure 34. Graph showing water-level fluctuations in well 46N/01E-06N01 in Butte

Valley, California ........................................................................... 58

Figure 35. Graphs showing water-level fluctuations in wells 40S/11E-11BAD in the

southern Poe Valley and well 40S/12E-30DCB north of Malin, Oregon ............... 58

Figure 36. Graphs showing water-level fluctuations in wells 39S/11E-26ABD and

39S/12E-35ADD in the western Langell Valley, Oregon ................................. 59

Figure 37. Graph showing water-level fluctuations in well 41S/09E-12AAB at the

southern end of the Klamath Hills, Oregon ............................................. 60

Figure 38. Map showing water-level decline between spring and fall 2004 in the Klamath

Valley and Tule Lake areas, upper Klamath Basin, Oregon and California ......... 61

Figure 39. Graph showing water-level fluctuations in well 48N/04E-35L02 near the town

of Tulelake, California ..................................................................... 62

Figure 40. Map showing water-level decline between spring 2001 and spring 2004 in the

Klamath Valley and Tule Lake areas, Oregon and California ........................... 63

Figures—Continued
viii

Conversion Factors and Datums

Conversion Factors

Multiply By To obtain

acre 0.004047 square kilometer (km2

)

acre-foot (acre-ft) 1,233 cubic meter (m3

)

acre-foot per year (acre-ft/yr) 1,233 cubic meter per year (m3

/yr)

cubic foot (ft3

) 0.02832 cubic meter (m3) 

cubic foot per second (ft3

/s) 0.02832 cubic meter per second (m3/s)

cubic foot per second per mile 

[(ft3

/s)/mi]

0.0176 cubic meter per second per kilometer 

[(m3/s)/km]

foot (ft) 0.3048 meter (m)

foot per day (ft/d) 0.3048 meter per day (m/d)

foot per mile (ft/mi) 0.1894 meter per kilometer (m/km)

foot squared per day (ft2

/d) 0.09290 meter squared per day (m2/d) 

gallon (gal) 3.785 liter (L) 

gallon per day per foot [(gal/d)/ft] 0.01242 cubic meter per day per meter 

[(m3

/d)/m]

gallon per minute (gal/min) 0.06309 liter per second (L/s)

inch (in.) 2.54 centimeter (cm)

inch per year (in/yr) 25.4 millimeter per year (mm/yr)

mile (mi) 1.609 kilometer (km)

million gallons (Mgal) 3,785 cubic meter (m3

)

million gallons per day (Mgal/d) 0.04381 cubic meter per second (m3

/s)

square foot (ft2

) 0.09290 square meter (m2)

square mile (mi2

) 2.590 square kilometer (km2) 

Temperature in degrees Fahrenheit (°F) may be converted to degrees Celsius (°C) as follows:

 °C = (°F-32)/1.8.

Datums

Horizontal coordinate information is referenced to the North American Datum of 1927 (NAD 27).

Vertical coordinate information is referenced to the National Geodetic Vertical Datum of 1929 

(NGVD 29). In this report, “altitude” refers to the distance above the vertical datum.

*Transmissivity: The standard unit for transmissivity is cubic foot per day per square foot times 

foot of aquifer thickness [(ft3

/d)/ft2]ft. In this report, the mathematically reduced form, foot 

squared per day (ft2/d), is used for convenience.
ix

Location System

The system used for locating wells and springs in this report is based on the rectangular system 

for subdivision of public land. The States of Oregon and California are divided into 36 squaremile townships numbered according to their location relative to an east-west baseline and a 

north-south meridian. In Oregon, the Willamette base line and meridian are used, and in California, the Mount Diablo baseline and meridian are used. The position of a township is given by 

its north-south “Township” position relative to the baseline and its east-west “Range” position 

relative to the meridian. Each township is divided into 36 sections approximately 1 square mile 

(640-acre) in area and numbered from 1 to 36. For example, a well designated as 36S/11E20DCA is located in Township 36 south, Range 11 east, section 20. The three letters following the section number (A,B,C, or D) correspond to the location within the section; the first 

letter identifies the quarter section (160 acres), the second letter identifies the quarter-quarter 

section (40 acres), and the third letter identifies the quarter-quarter-quarter section (10 acres). 

Thus, well 20DCA is located in the NE quarter of the SW quarter of the SE quarter of section 

20. When more than one designated well occurs in the quarter-quarter-quarter section, a serial 

number is appended. For some wells that were field located during previous studies or by the 

California Department of Water Resources, a different system of letters following the section 

number was used for the location within the section. This system assigns a letter to one of 16 

quarter-quarter sections (40 acres) that divide the section. The location 20DCA corresponds to 

the location 20Q. When more than one designated well occurs in the quarter-quarter section, a 

serial number is appended.

T. 36 S. 

T. 34 S. 

R. 8 E. R. 10 E. R. 12 E. R. 14 E.

24

123456

7 8 9 10 11 12

131415161718

19 20 21 22 23

252627282930

31 32 33 34 35 36

36S/11E-20DCA 36S/11E-20Q

B A

C AB

C D

D

AB

C D

20

JK

Q R

AB

G H

CD

E F

LM

N P

20
x

Mapping Sources

Base modified from U.S. Geological Survey 1:100,000 and 1:24,000 scale quadrangle maps. 

Relief from U.S. Geological Survey National Elevation Data Set 30 meter digital elevation 

model. Klamath Reclamation Project boundaries are from Bureau of Reclamation, Klamath 

Basin Area Office GIS data.

Vertical datum: National Geodetic Vertical Datum of 1929 (NGVD29)

Projection: Universal Transverse Mercator, Zone 10, 1927 North American Datum

Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California
Abstract

The upper Klamath Basin spans the California-Oregon 

border from the flank of the Cascade Range eastward to the 

Basin and Range Province, and encompasses the Klamath 

River drainage basin above Iron Gate Dam. Most of the basin 

is semiarid, but the Cascade Range and uplands in the interior 

and eastern parts of the basin receive on average more than 

30 inches of precipitation per year. The basin has several 

perennial streams with mean annual discharges of hundreds 

of cubic feet per second, and the Klamath River at Iron Gate 

Dam, which represents drainage from the entire upper basin, 

has a mean annual discharge of about 2,100 cubic feet per 

second. The basin once contained three large lakes: Upper and 

Lower Klamath Lakes and Tule Lake, each of which covered 

areas of 100 to 150 square miles, including extensive marginal 

wetlands. Lower Klamath Lake and Tule Lake have been 

mostly drained, and the former lake beds are now cultivated. 

Upper Klamath Lake remains, and is an important source 

of irrigation water. Much of the wetland surrounding Upper 

Klamath Lake has been diked and drained, although efforts 

are underway to restore large areas. Upper Klamath Lake and 

the remaining parts of Lower Klamath and Tule Lakes provide 

important wildlife habitat, and parts of each are included in the 

Klamath Basin National Wildlife Refuges Complex.

The upper Klamath Basin has a substantial regional 

ground-water flow system. The late Tertiary to Quaternary 

volcanic rocks that underlie the region are generally 

permeable, with transmissivity estimates ranging from 1,000 

to 100,000 feet squared per day, and compose a system of 

variously interconnected aquifers. Interbedded with the 

volcanic rocks are late Tertiary sedimentary rocks composed 

primarily of fine-grained lake sediments and basin-filling 

deposits. These sedimentary deposits have generally low 

permeability, are not good aquifers, and probably restrict 

ground-water movement in some areas. The regional groundwater system is underlain and bounded on the east and west 

by older Tertiary volcanic and sedimentary rocks that have 

generally low permeability. Eight regional-scale hydrogeologic 

units are defined in the upper Klamath Basin on the basis of 

surficial geology and subsurface data.

Ground water flows from recharge areas in the Cascade 

Range and upland areas in the basin interior and eastern 

margins toward stream valleys and interior subbasins. Ground 

water discharges to streams throughout the basin, and most 

streams have some component of ground water (baseflow). 

Some streams, however, are predominantly ground-water 

fed and have relatively constant flows throughout the year. 

Large amounts of ground water discharge in the Wood River 

subbasin, the lower Williamson River area, and along the 

margin of the Cascade Range. Much of the inflow to Upper 

Klamath Lake can be attributed to ground-water discharge 

to streams and major spring complexes within a dozen or so 

miles from the lake. This large component of ground water 

buffers the lake somewhat from climate cycles. There are 

also ground-water discharge areas in the eastern parts of the 

basin, for example in the upper Williamson and Sprague River 

subbasins and in the Lost River subbasin at Bonanza Springs.

Irrigated agriculture is an integral part of the economy of 

the upper Klamath Basin. Although estimates vary somewhat, 

roughly 500,000 acres are irrigated in the upper Klamath 

Basin, about 190,000 acres of which are part of the Bureau of 

Reclamation Klamath Project. Most of this land is irrigated 

with surface water. Ground water has been used for many 

decades to irrigate areas where surface water is not available, 

for example outside of irrigation districts and stream valleys. 

Ground water has also been used as a supplemental source 

of water in areas where surface water supplies are limited 

and during droughts. Ground water use for irrigation has 

increased in recent years due to drought and shifts in surfacewater allocation from irrigation to instream uses. The shifts in 

surface-water allocation have resulted from efforts to improve 

habitat for fish listed under the Federal Endangered Species 

Act.

The ground-water system in the upper Klamath Basin 

responds to external stresses such as climate cycles, pumping, 

lake stage variations, and canal operation. This response is 

manifest as fluctuations in hydraulic head (as represented 

by fluctuations in the water-table surface) and variations in 

ground-water discharge to springs. Basinwide, decadal-scale 

climate cycles are the largest factor controlling head and 

discharge fluctuations. Climate-driven water-table fluctuations 

of more than 12 feet have been observed near the Cascade 

Ground-Water Hydrology of the Upper Klamath Basin, 

Oregon and California

By Marshall W. Gannett, Kenneth E. Lite Jr., Jonathan L. La Marche, Bruce J. Fisher, and Danial J. Polette
Range, and decadal-scale fluctuations of 5 feet are common 

throughout the basin. Ground-water discharge to springs and 

streams varies basinwide in response to decadal-scale climate 

cycles.

The response of the ground-water system to pumping 

is generally largest in areas where pumping occurs. Annual 

drawdown and recovery cycles of 1 to 10 feet are common 

in pumping areas. Long-term drawdown effects, where the 

water table has reached or is attempting to reach a new level 

in equilibrium with the pumping, are apparent in parts of the 

basin.

Since 2001, ground-water use in the upper Klamath Basin 

has increased by about 50 percent. Much of this increase has 

occurred in the area in and around the Bureau of Reclamation 

Klamath Project, roughly tripling ground-water pumping in 

that area. This focused increase in pumping has resulted in 

ground-water level declines in the pumped aquifer in excess 

of 10 to 15 feet over a large part of the Project between 2001 

and 2004. If pumping rates of recent years are continued, 

the aquifer could achieve a new equilibrium; however, the 

final configuration of the water table (depth to water) and the 

spatial and temporal distribution of the resulting effects to 

streams are unknown. Historical water-level data suggest that 

the water table should recover from recent declines if pumping 

is reduced to pre-2001 rates.

Introduction

The upper Klamath Basin spans the Oregon-California 

border from the flank of the Cascade Range eastward to the 

high desert. Although much of the basin is high desert, the 

region receives considerable runoff from the Cascade Range 

and uplands to the east. As a result, the area has numerous 

perennial streams, large shallow lakes, and extensive wetlands, 

and the Klamath River has historically supported anadromous 

fish runs. Water in the basin is used for agricultural 

irrigation, for extensive waterfowl refuges, and to support 

aquatic wildlife in lakes and streams in the upper basin and 

downstream.

The agricultural economy of the upper Klamath Basin 

relies on irrigation water. Just over 500,000 acres are irrigated 

in the upper Klamath Basin, about 190,000 acres of which 

are within the Klamath Project developed and operated by the 

Bureau of Reclamation (Reclamation) (Burt and Freeman, 

2003; Natural Resources Conservation Service, 2004). The 

principal source of water for the Bureau of Reclamation 

Klamath Project is Upper Klamath Lake. In recent years, 

Endangered Species Act biological opinions have required 

Reclamation to maintain certain lake levels in Upper Klamath 

Lake to protect habitat for endangered fish (specifically 

the Lost River and shortnose suckers) and at the same time 

maintain specified flows in the Klamath River below the lake 

and project diversions to provide habitat for listed salmon. 

This shift in water management has resulted in increased 

demands for water. Owing to the limitations of other options, 

the increased demand has resulted in increased use of ground 

water in the basin. The problems associated with increased 

demands are exacerbated by drought.

The upper Klamath Basin has a substantial regional 

ground-water system, and ground water traditionally has 

been used for irrigation for many decades in certain areas. 

The changes in water management described above coupled 

with a series of dryer than average years have resulted in an 

approximately 50 percent increase in ground-water pumping 

in the basin since 2001. Most of this increase is focused in the 

area of the Klamath Project. Increased pumping has caused 

local water-level declines that have been problematic for some 

ground-water users and generated concern among resource 

management agencies and the community. In addition to the 

measured effects, the basic principles of hydrology require that 

the volume of ground-water pumped and used consumptively 

must be offset by changes in flow to or from other boundaries 

including streams.

The effects of large-scale ground-water pumping can 

spread beyond the pumping centers to other parts of the 

regional ground-water system. Prior to this study, the groundwater hydrology had been studied only in separate parts of the 

basin, with many areas left undescribed. Therefore, there was 

no basic framework with which to understand the potential 

regional effects of ground-water development in the basin 

and the broad ramifications of water-management decisions. 

In 1999, the U.S. Geological Survey (USGS) and the Oregon 

Water Resources Department (OWRD) began a cooperative 

study to (1) quantitatively characterize the regional groundwater flow system in the upper Klamath Basin and (2) develop 

a computer model to simulate regional ground-water flow 

that can be used to help understand the resource and test 

management scenarios. This report summarizes efforts to 

quantitatively characterize the ground-water hydrology.

Study Area

The upper Klamath Basin (fig. 1) comprises the 

entire drainage basin above Iron Gate Dam, including the 

internally drained Lost River and Butte Creek subbasins, 

and encompasses about 8,000 mi2 (square miles). Studyarea boundaries were defined to correspond to hydrologic 

boundaries across which ground-water flow can be estimated 

or assumed negligible. The southwestern boundary near 

Iron Gate Dam was selected because it corresponds with the 

transition from a geologic terrane dominated by permeable 

volcanic rock to a terrane dominated by older rock with much 

lower permeability. It is not likely that significant regional 

ground-water flow crosses this geologic boundary. The 

boundary between the regional flow systems in the upper 

Klamath Basin and the Deschutes and Fort Rock Basins to 

the north (not shown on fig. 1) is defined by a surface-water 

divide that roughly corresponds to the ground-water divide. 

2 Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California
OR19-0048_fig01

42°00'

41°30'

43°15'

43°00'

122°00' 121°00'

120°

45'

45'

45'

15'

45'

30'

30'

15' 122°30' 15'

5 0 5 10 15 20 MILES

Scale 1:1,000,000

5 0 5 10 15 20 KILOMETERS

OREGON

CALIFORNIA

Upper

Klamath

Basin

K L A M AT H

D O U G L A S

L A K E

M O D O C

S I S K I Y O U

J A C K S O N

Brownsworth

Creek

Butte

Creek

Cr

Whitney

Creek

Shasta River

Shovel

Bogus

Cr

Jenny

Cr

Fall

Cr

Edge Cr

Little Shasta River

River

Lost

Camp Cr

Scotch Cr

Dry Cr

Spencer

Whisky

Creek

Trout Cr

Larkin

Creek

Sycan

River

Spring

Creek

Wood

River

River

Long

Creek Williamson

Annie

Scott

Creek Sand

Creek

Springs

Big

Creek

Sheep

Creek

Sun

Creek

Creek

Brown

Creek

 Creek

 Buck

Cr

Mill Cr

Willow

Pit River

Miller Cr

Boles

Cr

Creek

Lost

River

River

River

River

Fork

Sprague

S Fork

N

Creek

Creek

Meryl

Fivemile

Cr

Creek

Jack

Sevenmile

Fourmile

Creek

Sprague

Sprague

Deming

Creek

Klamath

Strait

Keno

Dam Lost River 

Diversion

Channel

Creek

Rock

Annie

Spring

Klamath

River

Crater

Lake

Upper

Klamath

Lake

Summer Lake

Agency

Lake

Aspen

Lake

Lake

of the

Woods

Lake Ewauna

John C. Boyle Reservoir

Copco

Lake

Iron

Gate

Res Tule

Lake

Sump

Lower

Klamath

Lake Clear

Lake

Res

Gerber

Reservoir

John C. Boyle

Power Plant

Winter Ridge

Coleman Rim

Barns Rim

Mt

McLoughlin

Mount

Thielsen

Modoc Plateau

Sheepy Ridge

Bryant Mountain

Bly Ridge

Sycan

Marsh

Taylor

Butte Solomon

Butte

Pelican

Butte

Yainax

Butte

Gearhart

Mountain

Spodue

Mountain

Bly

Mt

Butte

Valley

Red Rock Valley

Chiloquin

Narrows

Rocky

Ford

Wildhorse

Ridge

Torrent

Spring

Kamkaun

Spring

Whitehorse Spring

McReady

Spring

Medicine

Lake

Volcano

Klamath Hills

North Canal

Klamath Valley

Yonna Valley

Swan Lake Valley

Yamsay

Mountain Klamath

Marsh

Knot Tableland

Beatty

Gap

OREGON

CALIFORNIA

Chemult Diamond 

Lake

Silver

Lake

Summer

Lake Lenz

Kirk

Chiloquin

Klamath

Agency

Fort

Klamath

Crater

Lake

Prospect

Butte

Falls Rocky

Point Modoc

Point

Klamath Falls

Pinehurst Keno

Dorris

Macdoel

Tulelake

Langell

Valley Malin

Merrill

Olene

Dairy

Bonanza

Lorella

Sprague

River

Beatty

Bly

31

138

138

230

140

140

139

299

62

62

70

66

66

97

97

5

Silver

Lake

C A S C A D E

R A N G E

Road

Study area

boundary

Area shown in figures 3, 20, 38, and 40

Brown

Spring

Mares Egg Spring

Wickiup

Spring

Miller

Creek

Sink

Creek

Cherry

Creek

Crane

Creek

Fourmile

Cr

The

Gap

Poe Valley

Stukel

Mountain

Fritz

Creek

Jackson

Creek

See table of contents for mapping sources

Figure 1. The upper Klamath Basin, Oregon and California, and major geographic features.

Introduction 3
This boundary is likely permeable. The boundary between the 

ground-water system of the upper Klamath Basin and that of 

the Pit River Basin to the south also is defined by a surfacewater divide in most places. The southern surface-water divide 

does not correspond to a ground-water divide in all places, as 

hydraulic head data indicate that there is southward flow of 

ground water from the upper Klamath Basin south of the Tule 

Lake subbasin toward the Pit River Basin. The eastern studyarea boundary corresponds to a surface-water divide and is 

characterized in many places by a transition to older geologic 

strata.

The upper Klamath Basin occupies a broad, faulted, 

volcanic plateau that spans the boundary between the Cascade 

Range and Basin and Range geologic provinces. The basin 

is bounded by the volcanic arc of the Cascade Range on the 

west, the Deschutes Basin to the north, the internally drained 

Silver Lake, Summer Lake, and Goose Lake Basins to the 

east, and the Pit River Basin to the south. The altitude of the 

Cascade Range along the western margin ranges from 5,000 

to 7,000 ft (feet) with major peaks such as Mount McLoughlin 

and Mount Thielsen exceeding 9,000 ft. The interior parts of 

the basin are dominated by northwest-trending fault-bounded 

basins, typically several miles wide, with intervening uplands. 

Basin floors range in altitude from roughly 4,000 to 4,500 ft, 

and adjoining fault-block upland altitudes range from 4,500 to 

more than 5,000 ft. The northern and eastern parts of the upper 

Klamath Basin consist of a volcanic upland with numerous 

eruptive centers, including Yamsay and Gearhart Mountains, 

both of which exceed 8,000 ft. The southeastern margin of 

the upper Klamath Basin consists of a broad, rugged, volcanic 

upland known as the Modoc Plateau, where most of the land 

surface ranges from 4,500 to 5,000 ft. The southern margin 

of the basin is marked by the broad shield of Medicine Lake 

Volcano, which reaches an altitude of 7,913 ft.

The upper Klamath Basin is semiarid because the 

Cascade Range intercepts much of the moisture from the 

predominantly eastward moving Pacific weather systems. 

Mean annual precipitation (1961–90) ranges from 65.4 inches 

at Crater Lake National Park in the Cascade Range to 13.5 

inches at Klamath Falls (fig. 2). Most precipitation occurs in 

the fall and winter. November through March precipitation 

accounts for 71 percent of the total at Crater Lake and 64 

percent of the total at Klamath Falls. Most precipitation falls 

as snow at higher elevations. The interior parts of the basin 

are very dry during the spring and summer; mean monthly 

precipitation at Klamath Falls is less than 1 inch from April 

through October. Winters are generally cold, with January 

mean minimum and maximum temperatures of 20.3°F and 

38.8°F, respectively, at Klamath Falls and 17.5°F and 34.5°F, 

respectively, at Crater Lake. Summers, in contrast, are warm, 

with July mean minimum and maximum temperatures of 

50.8°F and 84.6°F, respectively, at Klamath Falls and 39.8°F 

and 68.0°F, respectively, at Crater Lake.

Principal streams in the upper Klamath Basin include the 

Williamson River, which drains the northern and eastern parts 

of the basin; the Sprague River (a tributary to the Williamson) 

which drains part of the eastern side of the basin; the Lost 

River, which drains the southeastern part of the basin; and the 

Klamath River (fig. 1). The Lost River subbasin is actually a 

closed stream basin. Prior to development, the river flowed to 

internally drained Tule Lake, although it occasionally received 

flow from the Klamath River during floods. The Lost River 

is now diverted just below Olene into a channel across a low 

divide to the Klamath River. Generally, little water from the 

Lost River drainage above the diversion channel now flows to 

the Tule Lake subbasin. The largest lake in the basin is Upper 

Klamath Lake, which has a surface area between 100 and 140 

mi2

 (including non-drained fringe wetlands) depending on 

stage (Hubbard, 1970; Snyder and Morace, 1997). Principal 

tributaries to Upper Klamath Lake include the Williamson 

River, the Wood River (which originates at a series of large 

springs north of the lake), and several streams emanating from 

the Cascade Range.

The 250-mi (mile)-long Klamath River begins at the 

outlet of Upper Klamath Lake, which is controlled by a dam. 

For the first mile downstream of the lake, the river is known 

as the Link River. About 1 mi below the dam, the river flows 

into a 20-mi-long narrow reservoir behind Keno Dam known 

as Lake Ewauna. The dam for another impoundment, John 

C. Boyle Reservoir, is about 10 mi below Keno Dam. Below 

John C. Boyle Dam, the river enters a narrow canyon and 

flows freely about 20 mi to Copco Lake (a reservoir) and 

immediately below that, Iron Gate Reservoir. Iron Gate Dam, 

at about river mile 190, marks the downstream boundary of 

the upper Klamath Basin. There are no impoundments on the 

Klamath River below Iron Gate Dam.

The surface hydrology of the upper Klamath Basin 

has been extensively modified by drainage of lakes and 

wetlands for agriculture and routing of irrigation water. 

Prior to development, the Tule Lake and Lower Klamath 

Lake subbasins contained large lakes fringed by extensive 

wetlands. Under natural conditions, the Lost River flowed 

from the upper Lost River subbasin through the gap near 

Olene and then south to Tule Lake. The Lost River system 

received flow from the Klamath River system during periods 

of flood. Prior to development of the Bureau of Reclamation 

Klamath Project, the high stage of Tule Lake was about 4,060 

ft (La Rue, 1922). At this stage, the lake would cover an area 

exceeding 96,000 acres. Historical accounts indicate that at 

high stage Tule Lake drained into the lava flows along the 

southern margin. In the early 1900s, the U.S. Reclamation 

Service (predecessor to the Bureau of Reclamation) 

experimented with augmenting this subsurface drainage in 

early attempts to drain the lake. La Rue (1922) argued that 

the fact that the water of Tule Lake was fresh, and not saline, 

was proof that the lake “in the past had an outlet.” Subsurface 

drainage is also suggested by the hydraulic head gradient that 

slopes southward away from the Tule Lake subbasin toward 

the Pit River Basin. In 1912, a canal and dam were completed 

that allowed the diversion of water from the Lost River to 

the Klamath River, cutting off the supply of water to Tule 

Lake. Most of the Tule Lake Basin was drained and is now 

4 Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California
OR19-0048_fig02

Klamath

Falls

Malin

Dorris

Bonanza

Chiloquin

Crater

Lake

Clear

Lake

Upper

 Klamath

 Lake

Lower

Klamath

Lake Tule

Lake

North Fork

South Fork Sprague

Lost River

Williamson

River

River

River

River

Sycan

Klamath

138

140

140

139

62

66

97

97

!.

!.

!.

!.

!.

!.

!. !.

!.

!.

40

30

20

20

20

20

20

20

20

50

20

20

20

20

30

40

40

40

50

60

30

30

50

40

60

50

50 60

70

60

20

30

30

30

30

40

40

30

30

30

30

30

122°30'

121°30'

121°00'

122°00'

41°30'

43°00'

0 10 20 30 40 50 MILES

0 10 20 30 40 50 KILOMETERS

42°30'

42°00'

20

EXPLANATION

Line of equal precipitation—

 Interval 10 inches

Precipitation station

CALIFORNIA

OREGON

MEAN MONTHLY PRECIPITATION,

IN INCHES

SPRAGUE RIVER

0

2

4

6

8

10

12

O N D J F M A M J J A S

MEAN MONTHLY PRECIPITATION,

IN INCHES

KLAMATH FALLS

0

2

4

6

8

10

12

O N D J F M A M J J A S

MEAN MONTHLY PRECIPITATION,

IN INCHES

TULE LAKE

0

2

4

6

8

10

12

O N D J F M A M J J A S

MEAN MONTHLY PRECIPITATION,

IN INCHES

ROUND GROVE

0

2

4

6

8

10

12

O N D J F M A M J J A S

MEAN MONTHLY PRECIPITATION,

IN INCHES

CRATER LAKE

0

2

4

6

8

10

12

O N D J F M A M J J A S

MEAN MONTHLY PRECIPITATION,

IN INCHES

HOWARD PRAIRIE DAM

0

2

4

6

8

10

12

O N D J F M A M J J A S

MEAN MONTHLY PRECIPITATION,

IN INCHES

MOUNT HEBRON

0

2

4

6

8

10

12

O N D J F M A M J J A S MEAN MONTHLY PRECIPITATION, IN INCHES

CHEMULT

0

2

4

6

8

10

12

O N D J F M A M J J A S

1961–90 mean 

annual total, 

24.9 inches 1961–90 mean 

annual total, 

13.5 inches

1961–90 mean 

annual total, 

16.2 inches

1961–90 mean 

annual total, 

17.8 inches

1961–90 mean 

annual total, 

65.4 inches

1961–90 mean 

annual total, 

32.8 inches

1961–90 mean 

annual total, 

12.6 inches

1961–90 mean 

annual total, 

11.1 inches

Figure 2. Distribution of precipitation in the upper Klamath Basin, Oregon and California, and mean monthly precipitation at 

selected precipitation measurement stations. (Data from Oregon State University PRISM Group, 2006; and Western Regional 

Climate Center, 2006.)

Introduction 5
under cultivation. The only remnant of the lake is the Tule 

Lake Sump in the southern and western parts of the basin 

that collect irrigation return flow. Since 1942, water from the 

sump has been pumped via tunnel through Sheepy Ridge into 

the Lower Klamath Lake subbasin. The Lower Klamath Lake 

subbasin once held a large lake-marsh complex that covered 

approximately 88,000 acres, about 58,000 acres of which were 

marginal wetlands with the remaining 30,000 acres open water 

(La Rue, 1922). Lower Klamath Lake was connected to the 

Klamath River through a channel known as the Klamath Strait, 

and probably through the expansive wetland that separated the 

lake from the river elsewhere. In the early 1900s, a railroad 

dike was constructed across the northwestern margin of the 

Lower Klamath Lake subbasin, cutting off flow between 

the lake and river except at the Klamath Strait. In 1917, the 

control structure at the Klamath Strait was closed, cutting 

off flow to the lake. As a result, Lower Klamath Lake is now 

largely drained, with much of the former lake bed and fringe 

wetlands under cultivation. Areas of open water remain in the 

Lower Klamath Lake Wildlife Refuge in the southern part of 

the subbasin.

Currently (2007), about 500,000 acres of agricultural land 

are irrigated in the upper Klamath Basin, roughly 190,000 of 

which are included in the Bureau of Reclamation Klamath 

Project (fig. 3) (Carlson and Todd, 2003; Natural Resources 

Conservation Service, 2004). This total does not include 

wildlife refuge areas within the Project.

The upper Klamath Basin is mostly forested (Loy and 

others, 2001). Forest trees in upland areas east of the Cascade 

Range are predominantly ponderosa pine, with areas of true fir 

and Douglas fir on Yamsay and Gearhart Mountains. Forests 

in the Cascade Range are composed primarily of mountain 

hemlock and red fir. Lower elevation uplands are dominated 

by lodgepole pine. Lowland forests consist largely of juniper 

and sagebrush with some juniper grasslands. Stream valleys 

and the broad, sediment-filled structural basins generally 

have extensive marshes, such as Sycan Marsh and Klamath 

Marsh, except at lower elevations, where the basins have been 

mostly converted to agricultural land (for example, the Wood 

River Valley, and the Lower Klamath Lake and Tule Lake 

subbasins).

The population of the upper Klamath Basin is 

approximately 70,000. Klamath County, most of which is in 

the upper Klamath Basin, had a population of 64,600 in 2003, 

most of which live in the Klamath Falls area (Oregon Blue 

Book, 2006). Few people live outside Klamath County in the 

Oregon part of the basin. The population in the California part 

of the upper Klamath Basin is difficult to estimate. Population 

in the block groups from the 2000 census that include the 

populated parts of Modoc and Siskiyou Counties in the basin 

is slightly more than 3,000. Some small settlements and 

ranches may not be included in these block groups.

Principal sectors of the economy in the upper Klamath 

Basin, in terms of output and employment, include forest 

products, agriculture, construction, retail, health care, and 

services (Weber and Sorte, 2003). In the agricultural sector, 

principal crops include (in approximate order, with largest 

acreages first) alfalfa hay, irrigated pasture, grains, and 

potatoes (Carlson and Todd, 2003; Siskiyou County, 2003). 

The proportions vary slightly between land inside and outside 

the Bureau of Reclamation Klamath Project, and between land 

in Oregon and California. Project lands in California tend to 

include more grains than alfalfa. Most agricultural land in the 

upper Klamath Basin (not including rangeland) is irrigated. 

A substantial part of the local economy, therefore, relies on 

irrigation water.

Irrigation water comes from a variety of sources in the 

upper Klamath Basin. Upstream of Upper Klamath Lake, in 

the Williamson, Sprague, and Wood River drainages, private 

(non-Project) irrigation water comes primarily from diversion 

of surface water from the main-stem streams or tributaries. 

A smaller amount of irrigation water is pumped from ground 

water, particularly in the Sprague River Valley and Klamath 

Marsh areas. In the Langell and Yonna Valleys of the upper 

Lost River subbasin, irrigation water comes from Clear Lake 

and Gerber Reservoirs. Irrigators use ground water and some 

surface water in Swan Lake Valley. Ground water is used 

for irrigation in areas not served by irrigation districts and to 

supplement surface-water supplies throughout the area.

South of Upper Klamath Lake, most irrigation water 

comes from the lake, which is the largest single source of 

irrigation water in the upper Klamath Basin. This area is the 

main part of the Bureau of Reclamation Klamath Project. 

Water is stored in and diverted from the lake to irrigate land 

south of Klamath Falls, including the Klamath Valley, Poe 

Valley (in the Lost River subbasin upstream of Olene Gap), 

and the Tule Lake subbasin. Irrigation return flow (water that 

originates in Upper Klamath Lake) that ends up in the Tule 

Lake Sump is pumped through Sheepy Ridge and used for 

irrigation and refuge use in the southern part of the Lower 

Klamath Lake subbasin. Water diverted from the Klamath 

River several miles downstream of the lake also is used for 

irrigation and refuges in the Lower Klamath Lake subbasin. 

Irrigation and refuge return flow in the Lower Klamath Lake 

subbasin is routed back up the Klamath Strait drain through a 

series of pumping stations to the Klamath River.

A certain amount of ground water is used for irrigation 

on land surrounding the Klamath Project upslope of the major 

canals. Principal areas of ground-water use surrounding the 

Project area include the southern end of the Klamath Hills, 

parts of the Klamath Valley, and the northern and eastern 

margins of the Tule Lake subbasin (fig. 1). Some ground 

water traditionally has been used for supplemental irrigation 

in the Project area. Increased water demand due to drought 

and requirements for a 100,000 acre-ft pilot water bank placed 

on Reclamation by the National Oceanic and Atmospheric 

Administration (NOAA) Fisheries 2002 biological opinion 

(National Marine Fisheries Service, 2002) have resulted in a 

marked increase in ground-water pumping in and around the 

Klamath Project since 2001.

6 Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California
OR19-0048_fig03

Lower 

Klamath

Lake

Upper 

Klamath

Lake

KLAMATH

RIVER

122°00' 45' 30' 121°15'

42°00'

42°15'

41°45'

0 5 10 15 MILES

0 5 10 KILOMETERS

See table of contents for mapping sources

OREGON

CALIFORNIA

EXPLANATION

Irrigated area within the 

Klamath Project

River

Lost

Miller Cr

Lost

River

Sprague River

Lake

Ewauna

Tule

Lake

Sump Clear

Lake

Res

Modoc

Point

Klamath Falls

Keno Midland

Worden

Dorris Tulelake

Langell

Valley

Merrill Malin

Henley

Altamont

Olene

Dairy

Bonanza

Lorella

Sprague

River Beatty

Klamath

Strait

Keno

Dam

Lost River 

Diversion

Channel

Sheepy Ridge

Bryant Mountain

Bly Ridge

Yainax

Butte

Bly

Mt

Butte

Valley

Klamath Hills

Klamath Valley

Swan Lake Valley

Figure 3. Irrigated areas in the Bureau of Reclamation Klamath Project, Oregon and California.

Introduction 7
Purpose and Scope

This report summarizes the present understanding of 

regional ground-water flow in the upper Klamath Basin 

resulting from the USGS–OWRD cooperative study. The 

report provides a description of the ground-water hydrology 

for resource managers, water users, and those with a general 

interest. It is also intended to provide sufficient quantitative 

information useful to hydrologists working in the basin, and to 

provide background for subsequent reports and investigations.

The report is regional in scope. Thus, data and analysis 

presented herein are intended to provide an understanding of 

the ground-water hydrology at a regional scale. Although the 

information and interpretations are useful for understanding 

the hydrologic setting of smaller areas, the ground-water 

hydrology of local areas is generally not discussed in detail.

The report covers many key aspects of the regional 

ground-water system. A summary of the geologic framework 

of the regional ground-water system is presented that is 

based on existing geologic mapping, field reconnaissance, 

radiometric age dates, and interpretation of lithologic data 

from more than 1,000 wells. A regional ground-water 

budget (including recharge and discharge), calculated 

from precipitation data, streamflow data, measured and 

estimated ground-water discharge to streams, and estimated 

evapotranspiration, also is provided. The distribution of 

hydraulic head, which controls ground-water flow directions, 

was estimated from water-level measurements in more than 

1,000 wells, altitudes of gaining stream reaches, and altitudes 

of hundreds of springs mapped on USGS quadrangle maps. 

The response of the flow system to climate variations and 

pumping stresses was determined by using time-series waterlevel measurements from wells throughout the basin, with 

frequencies ranging from hours to months and periods ranging 

from years to decades, and from streamflow data.

Geologic Framework

Geologic Controls on Ground-Water Flow

The principal geologic factors that influence ground 

water are the porosity and permeability of the rock or 

sediment through which it flows. Porosity, in general terms, 

is the proportion of a rock or deposit that consists of open 

space. In a gravel deposit, this would be the proportion of the 

volume of the deposit represented by the space between the 

individual pebbles and cobbles. Permeability is a term used 

to describe the ease with which a fluid can move through 

a material such as rock or sedimentary deposits. Deposits 

with large interconnected open spaces, such as gravel, offer 

little resistance to ground-water flow and are, therefore, 

usually highly permeable. Rocks with few, very small, or 

poorly connected open spaces offer considerable resistance to 

ground-water flow and, therefore, have low permeability. The 

hydraulic characteristics of geologic materials vary between 

and within rock types. For example, in sedimentary deposits 

the permeability is a function of grain size and the range of 

grain sizes (the degree of sorting). Coarse, well-sorted gravel 

has much higher permeability than well-sorted sand. A wellsorted sand or gravel has a higher permeability than a deposit 

that is poorly sorted and has the open spaces between pebbles 

or sand grains filled with silt or clay. Clay-rich deposits 

generally have very low permeability. The permeability of 

lava flows also can vary markedly depending on the degree of 

fracturing. The highly fractured, rubbly zones at the tops and 

bottoms of lava flows and in interflow zones are often highly 

permeable, whereas the dense interior parts of lava flows 

can have very low permeability. Weathering and secondary 

mineralization, which often are a function of the age of 

the rock, can strongly influence permeability. Sedimentary 

deposits or lava flows in which the original open spaces 

have been filled with secondary minerals can have very low 

permeability.

Geologic properties that influence the movement of 

ground water within a flow system also can define the 

boundaries of the system. Geologic terranes consisting of 

predominantly low-permeability materials can form the 

boundaries of a regional flow system.

General Geology

The upper Klamath Basin has been a region of volcanic 

activity for at least 35 million yr (years) (Sherrod and Smith, 

2000), resulting in complex assemblages of volcanic vents 

and lava flows, pyroclastic deposits, and volcanically derived 

sedimentary deposits. Volcanic and tectonic processes have 

created many of the present-day landforms in the basin. 

Glaciation and stream processes have subsequently modified 

the landscape in many places.

The upper Klamath Basin lies within two major geologic 

provinces, the Cascade Range and the Basin and Range 

Province (Orr and others, 1992). The processes that have 

operated in these provinces have overlapped and interacted 

in much of the upper Klamath Basin. The Cascade Range 

is a north-south trending zone of compositionally diverse 

volcanic eruptive centers and their deposits extending from 

northern California to southern British Columbia. The 

Cascade Range is subdivided between an older, highly eroded 

Western Cascades, and a younger, mostly constructional 

High Cascades. Prominent among the eruptive centers in the 

High Cascades of the Klamath Basin are large composite 

and shield volcanoes such as Mount Mazama (Crater Lake), 

Mount McLoughlin, and Medicine Lake Volcano. The 

Cascade Range has been impinged on its eastern side by the 

adjacent structurally dominated Basin and Range Province. 

The Basin and Range Province is a region of crustal extension 

characterized by subparallel, fault-bounded, down-dropped 

8 Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California
basins separated by fault-block ranges. Individual basins and 

intervening ranges are typically 10–20 mi across. The Basin 

and Range Province encompasses much of the interior of 

the Western United States, extending from central Oregon 

southward through Nevada and western Utah, into the southern 

parts of California, Arizona, and New Mexico. Although the 

Basin and Range Province is primarily structural, faulting has 

been accompanied by widespread volcanism.

The oldest rocks in the upper Klamath Basin study area 

are part of the Western Cascades subprovince and consist 

primarily of lava flows, andesitic mudflows, tuffaceous 

sedimentary rocks, and vent deposits. The Western Cascade 

rocks range in age from 20 to 33 million years (my) and are 

as much as 20,000 ft thick (Hammond, 1983; Vance, 1984). 

Rocks of the Western Cascades overlie pre-Tertiary rocks of 

the Klamath Mountains Province, just west of the study area. 

Western Cascades rocks have very low permeability because 

the tuffaceous materials are mostly devitrified (changed to 

clays and other minerals), and lava flows are weathered and 

contain abundant secondary minerals. Because of the low 

permeability, ground water does not easily move through 

the Western Cascades rocks, and the unit acts as a barrier to 

regional ground-water flow. The Western Cascades constitute 

part of the western boundary of the regional ground-water 

flow system. Western Cascade rocks dip toward the east and 

underlie the High Cascade deposits, and define the lower 

boundary of the regional flow system throughout that part of 

the study area.

The High Cascade subprovince ranges in age from late 

Miocene (7 my) to Recent; however, most rocks are Pliocene 

(5 my) to Recent in age (Mertzman, 2000). Deposits within 

the High Cascade subprovince in the study area mostly form 

constructional features and consist of volcanic vents and lava 

flows with relatively minor interbedded volcaniclastic and 

sedimentary deposits. An area of numerous late Miocene 

to Pliocene cinder cones extends from southwest of Butte 

Valley to northwest of Mt. Mazama (Crater Lake). Quaternary 

volcanic deposits are associated with a few volcanic centers 

concentrated in two general areas in the upper Klamath 

Basin: from Lake of the Woods north to Crater Lake and 

from Mt. Shasta (south of the study area) east to Medicine 

Lake Volcano. The High Cascades rocks are relatively thin in 

southern Oregon and northern California, typically measured 

in hundreds of feet thick, rather than thousands (Stan 

Mertzman, Franklin and Marshall College, written commun., 

2003). High Cascade rocks unconformably overlie Western 

Cascade rocks and are very permeable, relative to the older 

rocks.

Basin and Range Province deposits in the study area 

range in age from middle Miocene (13 my) to Recent. The 

oldest rocks are middle to late Miocene in age, ranging from 

13 to 8 my. These rocks are exposed just south of the study 

area in the Pit River Basin and are equivalent to the upper 

Cedarville Series of Russell (1928). In the study area, those 

rocks probably underlie the Pliocene age lavas south of Clear 

Lake Reservoir. The older rocks in the Pit River Basin and 

bounding the eastern part of the study area are mostly silicic 

domes, flows, and pyroclastic deposits, which generally have 

low permeability (California Department of Water Resources, 

1963) and typically are faulted and tilted.

Late Miocene to Pliocene volcanic rocks of the Basin and 

Range Province are the major water bearing rocks in the upper 

Klamath Basin study area. These units consist of volcanic 

vent deposits and flow rocks throughout the area east of 

Upper Klamath Lake and Lower Klamath Lake, and probably 

underlie most of the valley- and basin-fill deposits in the study 

area. Late Miocene to Pliocene rocks also form uplands along 

the eastern boundary of the study area, and form the plateau 

that extends from the Langell Valley south to the Pit River. 

The rocks are predominately basalt and basaltic andesite in 

composition, but silicic vents and lava flows occur locally, 

notably in the vicinity of Beatty, Oregon.

Tuff cones and tuff rings are the predominant volcanic 

vent form in the Sprague River subbasin between Chiloquin 

and Sprague River, Oregon. Tuff cones and rings form when 

rising magma comes in contact with water, resulting in 

explosive fragmentation of the volcanic material. The late 

Miocene to Pliocene rocks typically exhibit high to very 

high permeability. However, the permeability locally may 

be markedly reduced by secondary mineralization from 

hydrothermal alteration.

The volcanic rocks of the Basin and Range Province are 

interbedded with, and locally overlain by, late Miocene to 

Pliocene sedimentary rocks. The sedimentary rocks consist of 

tuffaceous sandstone, ashy diatomite, mudstone, siltstone, and 

some conglomerates. These units are exposed both in downdropped basins and in up-thrown mountain blocks, indicating 

that the deposits in part represent an earlier generation of 

sediment-filled basins have been subsequently faulted and 

uplifted. These sedimentary deposits are typically poor water 

producers, and often serve as confining layers for underlying 

volcanic aquifers.

The youngest stratigraphic unit in the upper Klamath 

Basin consists of late Pliocene to Recent sedimentary deposits. 

Those deposits include alluvium along modern flood plains, 

basin-fill deposits within active grabens, landslide deposits, 

and glacial drift and outwash. Very thick accumulations 

of silt, sand, clay, and diatomite underlie the westernmost 

basins, such as the Upper Klamath Lake, Lower Klamath 

Lake, Butte Valley, and Tule Lake subbasins. For example, 

up to 1,740 ft of basin-fill sediment underlies the town of 

Tulelake, California. Sediment near the base of the deposit at 

Tulelake has been assigned an age of 3.3 my on the basis of 

radiometric ages of interbedded tephra, paleomagnetic data, 

and estimates of sedimentation rates (Adam and others, 1990). 

Gravity data suggest that the sediment-fill thickness may 

exceed 6,000 ft in the Lower Klamath Lake subbasin and may 

be in the range of 1,300 to 4,000 ft in the Upper Klamath Lake 

subbasin (Sammel and Peterson, 1976; Veen, 1981; Northwest 

Geophysical Associates Inc., 2002).

Geologic Framework 9
Hydrogeologic Units

Hundreds of distinct and mappable geologic units have 

been identified by geologists in the upper Klamath Basin. 

Many of these geologic units have very similar hydrologic 

characteristics. For purposes of the description and analysis 

of regional ground-water flow, geologic units are typically 

combined into a smaller number of hydrogeologic units. 

Hydrogeologic units consist of groupings of geologic units 

that contain rock types of similar hydrologic characteristics 

and are distinct from other units. The geology of the upper 

Klamath Basin is herein generalized into eight hydrogeologic 

units (fig. 4 and table 1). Pre-Tertiary rocks are not exposed in 

outcrops or penetrated by wells in the study area and are not 

discussed.

Early to mid-Tertiary volcanics and sediments (Tovs), 

the oldest hydrogeologic unit in the study area, comprises 

Miocene and older lava and volcaniclastic rocks of the 

Western Cascade subprovince along the western margin of 

the study area, as well as older volcanic deposits beneath late 

Tertiary lavas along the eastern margin. The unit also includes 

older rocks exposed in the Pit River Basin southeast of the 

study area. The permeability of this unit is generally low 

due to weathering, hydrothermal alteration, and secondary 

mineralization. This unit is herein considered a boundary to 

the regional ground-water system of the upper Klamath Basin.

Late Tertiary volcaniclastic deposits (Tvpt) include 

palagonitized basaltic ash and lapilli deposits associated with 

eruptive centers. The hydrologic characteristics of this unit 

are not well known, but springs emerge from basal contact 

with unit Ts. This unit is most prominent in the Sprague River 

Valley.

Late Tertiary sedimentary rocks (Ts) consist 

predominately of fine-grained continental sedimentary 

deposits that include bedded diatomite, mudstone, siltstone, 

and sandstone. This unit has generally low permeability. 

These deposits occur throughout the central part of the upper 

Klamath Basin. They are exposed in uplands in interior parts 

of the basin and penetrated by wells in the river valleys. 

Lithologic logs of wells in the Sprague River Valley indicate 

that the thickness of these sedimentary deposits there locally 

exceeds 1,500 ft.

Late Tertiary volcanic rocks (Tv) consist predominately 

of basaltic and andesitic lava flows and vent deposits, but 

the unit includes local silicic domes and flows. This unit is 

locally affected by hydrothermal alteration and secondary 

mineralization. This is the most geographically extensive 

hydrogeologic unit, occurring throughout most of the upper 

Klamath Basin. The unit has moderate to high permeability 

and is by far the most widely developed aquifer unit in the 

study area.

Quaternary to late Tertiary sedimentary rocks (QTs) 

consist of medium- to coarse-grained unconsolidated to 

moderately indurated sedimentary deposits. The hydraulic 

characteristics of this unit are not well known, but lithologic 

EXPLANATION FOR FIGURE 4

Hydrogeologic unit present at land surface

 Quaternary sedimentary deposits

 Quaternary volcaniclastic deposits

 Quaternary volcanic rocks

 Quaternary to late Tertiary sedimentary rocks

 Late Tertiary sedimentary rocks

 Late Tertiary volcaniclastic rocks

 Late Tertiary volcanic rocks

 Older Tertiary volcanic and sedimentary rocks 

 Pre-Tertiary rocks

 Geologic fault, dashed where inferred, 

 dotted where concealed

NOTE: Geology generalized from: 

 Gay and Aune, 1958;

 Walker, 1963;

 Smith and others, 1982; 

 Wagner and Saucedo, 1987;

 Sherrod, 1991; 

 MacLeod and Sherrod, 1992; 

 Sherrod and Pickthorn, 1992, and

 Sherrod and Smith, 2000. 

Qs

Qvp

Qv

QTs

Ts

Tv

Tvpt

pT

Tovs

descriptions on maps suggest that it is moderately permeable 

at some locations. This unit occurs locally in the western 

Wood River Valley, south of Klamath Falls, and in the 

uppermost Williamson River subbasin.

Quaternary volcanics (Qv) consist primarily of basaltic 

and andesitic lavas and vent deposits occurring in the Cascade 

Range and around Medicine Lake Volcano. These materials 

are generally highly permeable.

Quaternary volcaniclastic deposits (Qvp) consist 

primarily of pyroclastic flows and air-fall material (pumice 

ash and lapilli) deposited during the climactic eruption of Mt. 

Mazama that formed the caldera encompassing Crater Lake. 

This unit is most extensive in the Cascade Range around 

Crater Lake and in the upper Williamson River subbasin. 

As mapped (fig. 4), the unit also includes debris avalanche 

deposits in the Shasta River Valley outside of the study area. 

Minor Quaternary pyroclastic deposits occur on Medicine 

Lake Volcano and in Butte Valley. Air-fall deposits are highly 

permeable.

Quaternary sediments (Qs) include the alluvial deposits 

in principal stream valleys, glacial deposits in the Cascade 

Range, and basin-filling sediments in the major lake basins. 

The basin-filling deposits are generally fine grained and have 

low permeability. Coarse facies occur at some locations within 

the basin-filling deposits.

10 Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California
OR19-0048_fig04a

42°00'

41°30'

43°15'

43°00'

122°00' 121°00'

120°

45'

45'

45'

15'

45'

30'

30'

15' 122°30' 15'

OREGON

CALIFORNIA

Upper

Klamath

Basin

Butte

Creek

Cr

Whitney

Creek

Shasta River

Shovel

Bogus

Cr

Jenny

Cr

Fall

Cr

Edge Cr

Little Shasta River

River

Lost

Camp Cr

Scotch Cr

Dry Cr

Spencer

Whisky

Creek

Trout Cr

Larkin

Creek

Sycan

River

Spring

Creek

Wood

River

River

Long

Creek Williamson

Annie

Scott

Creek Sand

Creek

Big

Springs

Creek

Sheep

Creek

Sun

Creek

Creek

Brown

Creek

 Creek

Mill Cr

Willow

Miller Cr

Boles

Cr

Creek

Lost

River

River

River

Sprague

River

S Fork

N

Creek

Creek

Meryl

Fivemile

Creek

Creek

Jack

Sevenmile

Sprague

Sprague

Klamath

Strait

Lost River 

Diversion

Channel

Klamath

River

Klamath

Marsh

Crater

Lake

Upper

Klamath

Lake

Summer Lake

Agency

Lake

Lake

of the

Woods

Lake Ewauna

John C. Boyle Reservoir

Copco

Lake

Iron

Gate

Res

Tule

Lake

Sump

Lower

Klamath

Lake Clear

Lake

Res

Gerber

Reservoir

Winter Ridge

Coleman Rim

Mt

McLoughlin

Gearhart Mountain

Sycan

Marsh

Taylor

Butte

Chiloquin

Narrows

Rocky

Ford

Torrent

Spring

Poe Valley

Butte

Valley

Medicine

Lake

Volcano

KLAMATH

DOUGLAS

LAKE

MODOC

S ISK IYOU

JACKSON

31

138

138

230

140

140

139

299

62

62

70

66

66

97

97

5

Silver

Lake

Road

Chemult Diamond 

Lake

Silver

Lake

Summer

Lake Lenz

Kirk

Chiloquin

Klamath

Agency

Fort

Klamath

Crater Lake

Prospect

Butte

Falls

Rocky

Point Modoc

Point

Klamath Falls

Pinehurst Keno

Dorris Tulelake Langell

Valley

Malin

Merrill

Olene

Dairy

Bonanza

Lorella

Sprague

River

Beatty

Bly

5 0 5 10 15 20 MILES

Scale 1:1,000,000

5 0 5 10 15 20 KILOMETERS

See table of contents for mapping sources

Figure 4. Hydrogeologic units of the upper Klamath Basin, Oregon and California.

Geologic Framework 11
Hydrogeologic unit Map symbol Lithologic and hydrologic characteristics

Quaternary 

sedimentary 

deposits

Qs Fine- to coarse-grained sediments deposited in stream valleys and major lake basins. Permeable coarsegrained deposits occur in stream valleys and locally in the lake basins. The lake basin deposits are, 

however, predominantly fine grained and have low permeability.

Quaternary 

volcaniclastic 

deposits

Qvp Pyroclastic flows and air fall material (pumice, ash, and lapilli) deposited during the climactic eruption 

of Mt. Mazama that formed Crater Lake, and debris avalanche deposits of the Shasta River Valley. Air 

fall deposits are highly permeable. Pyroclastic flows and debris deposits may have low permeability.

Quaternary volcanic 

rocks

Qv Basaltic and andesitic lavas and vent deposits occurring in the Cascade Range and around Medicine Lake 

Volcano. These materials are generally highly permeable, but may not be saturated at high elevations.

Quaternary to 

late Tertiary 

sedimentary rocks

QTs Fine- to coarse-grained unconsolidated to moderately indurated sedimentary deposits. The hydraulic 

characteristics of this unit are not well known but lithologic descriptions on maps suggest it may be 

moderately permeable at some locations. This unit has very limited distribution.

Late Tertiary 

sedimentary rocks

Ts Predominately fine-grained continental sedimentary deposits including bedded diatomite, mudstone, 

siltstone, and sandstone. This unit has generally low permeability but contains permeable strata at 

some locations.

Late Tertiary 

volcaniclastic 

rocks

Tvpt Palagonitized basaltic ash and lapilli deposits associated with eruptive centers. The hydrologic 

characteristics of this unit are not well known, but springs are known to emerge from basal contact 

with unit Ts. This unit is most prominent in the Sprague River valley.

Late Tertiary 

volcanic rocks

Tv Predominantly basaltic and andesitic lava flows and vent deposits with lesser amounts of silicic domes 

and flows. This unit has moderate to high permeability and is by far the most widely developed aquifer 

unit in the study area. Permeability is locally diminished by hydrothermal alteration and secondary 

mineralization.

Older Tertiary 

volcanic and 

sedimentary rocks

Tovs Miocene and older volcanic and volcaniclastic deposits. The permeability of this unit is generally low 

due to weathering, hydrothermal alteration, and secondary mineralization. This unit is generally 

considered a boundary to the regional ground-water system of the upper Klamath Basin.

Table 1. Generalized hydrogeologic units in the upper Klamath Basin, Oregon and California.

Effects of Geologic Structure

Geologic structures, principally faults and fault zones, 

can influence ground-water flow. Fault zones can act as either 

barriers to or conduits for ground-water flow, depending on 

the material in and between the individual fault planes. Faults 

most commonly affect ground-water flow by juxtaposing rocks 

of contrasting permeability or by affecting the patterns of 

deposition. Structural basins caused by normal faulting, called 

grabens, can act as depositional centers for large thicknesses 

of sediment or lava that may influence regional ground-water 

flow. Faults do not always influence ground-water flow; there 

are regions in the upper Klamath Basin where ground-water 

flow appears unaffected by the presence of faults.

The area of the upper Klamath Basin lying east of 

the Cascade Range is a composite graben that forms the 

westernmost structural trough of the Basin and Range 

physiographic province (Sherrod and Pickthorn, 1992). The 

predominant fault direction is north-northwest, as shown in 

figure 4. According to Sherrod and Pickthorn (1992), offset 

across the faults range from less than 300 ft in the central 

and eastern parts of the graben to about 6,000 ft on faults 

southwest of Klamath Falls.

Hydraulic Characteristics of Regional 

Hydrogeologic Units

Geologic materials possess certain hydraulic 

characteristics that control the movement and storage of 

ground water. This section describes the basic parameters 

used to characterize aquifer hydraulic properties and presents 

estimates or ranges of values of those terms for some of 

the major geologic units in the upper Klamath Basin. A 

more thorough discussion of the terms used to describe the 

hydraulic characteristics of aquifers and aquifer materials can 

be found in any basic ground-water hydrology text such as 

Freeze and Cherry (1979), Fetter (1980), or Heath (1983).

The term “permeability” was introduced previously as 

a measure of the ease with which fluid can move through a 

particular rock type or deposit. Permeability is an intrinsic 

property of the rock type, and is independent of the fluid 

properties. In ground-water studies, the term “hydraulic 

conductivity” is used more commonly than “permeability” in 

quantitative discussions. The hydraulic conductivity includes 

both the properties of the rock (the intrinsic permeability) 

and the properties of the water, such as viscosity and density. 

12 Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California
Hydraulic conductivity is generally defined as the volume of 

water per unit time that will pass through a unit area of an 

aquifer material in response to a unit hydraulic head gradient. 

Hydraulic conductivity has the units of volume per unit time 

(such as cubic feet per day) per unit area (such as square feet), 

which simplifies by division to length per unit time (such 

as feet per day). Hydraulic conductivity values for aquifer 

materials commonly span several orders of magnitude from 

less than 0.1 ft/d for fine sand and silt to over 1,000 ft/d for 

well-sorted sand and gravel.

When discussing aquifers instead of rock types, 

the hydraulic conductivity is multiplied by the aquifer 

thickness resulting in a parameter known as “transmissivity.” 

Transmissivity is defined as the volume of water per unit time 

that will flow through a unit width of an aquifer perpendicular 

to the flow direction in response to a unit hydraulic head 

gradient. Transmissivity has units of volume per unit time 

(such as cubic feet per day) per unit aquifer width (such as 

feet), which simplifies to length squared per unit time (such as 

feet squared per day [ft2/d]).

Storage characteristics of an aquifer are described by 

a parameter known as the “storage coefficient.” The storage 

coefficient is defined as the volume of water an aquifer 

releases from, or takes into, storage per unit area of aquifer per 

unit change in head. The volume of water has units of length 

cubed (such as cubic feet), the area has units of length squared 

(such as square feet), and the head change has units of length 

(such as feet). Thus, the storage coefficient is dimensionless. 

Storage coefficients typically span several orders of magnitude 

from 10-4 for aquifers with overlying confining units, to 0.1 

for unconfined aquifers. Storage coefficients commonly fall 

between these two end members because aquifers often have 

varying degrees of confinement. Note that characterizing 

an aquifer as “confined” does not imply that it is not 

hydraulically connected to other aquifers or to surface water. 

The terms “confined” and “unconfined” describe the physics 

of the aquifer response to pumping at a particular location.

The hydraulic characteristics of subsurface materials 

are typically determined by conducting aquifer tests. An 

aquifer test consists of pumping a well at a constant rate and 

measuring the change in water level (the drawdown) with time 

in the pumping well and nearby non-pumping wells. The data 

collected allow generation of a curve showing the drawdown 

as a function of time. Similar data are collected after the 

pumping is stopped, allowing generation of a curve showing 

the water-level recovery as a function of time. Analysis of 

the drawdown and recovery curves in the pumped well and 

observation wells provides estimates of the transmissivity 

and storage coefficient of the aquifer. Aquifer characteristics 

also can be estimated from certain well-yield tests called 

“specific-capacity tests,” sometimes conducted by drillers. 

Data from specific capacity tests that include a pumping rate, 

test duration, drawdown at the end of the test, and the well 

diameter can be used to estimate aquifer transmissivity.

Aquifer Tests

The results of 32 aquifer tests conducted in the upper 

Klamath Basin are summarized in table 2. The tests were 

conducted by the OWRD, the California Department of Water 

Resources (CDWR), private consultants, and the USGS. 

Pumping periods for the tests ranged from 12 hr (hours) 

to 169 days, with most lasting 24 to 72 hr. All tests were 

conducted on wells with large yields ranging from about 

1,000 to 10,000 gal/min. Most tests are of wells that produce 

from Tertiary volcanic deposits (unit Tv on fig. 4) because it 

is the most productive and widespread water bearing unit. A 

smaller number of tests were of wells producing from Tertiary 

sedimentary deposits (unit Ts on fig. 4) or a mixture of Ts and 

Tv. It should be noted that the Tertiary sediments are very fine 

grained over most of the basin, and that wells producing large 

yields from that unit occur only in specific locations.

Data and details of the analyses for most of the tests 

are available from sources listed in table 2. Reanalysis of the 

aquifer tests listed in table 2 was beyond the scope of this 

study. For the most part, the results presented are directly from 

the source documents, except that values have been rounded 

to two significant figures. In some cases, as noted in table 2, 

results from certain observation wells or certain analyses that 

were considered problematic were not included. For example, 

anomalous results from observation wells that were open to 

different water-bearing zones or constructed differently from 

the pumped well were excluded. Results from pumped wells 

were excluded where well loss (excessive drawdown due to 

well inefficiency) appeared to affect the results.

Most aquifer tests show evidence of boundaries, 

complicated aquifer geometry, or possible double-porosity 

conditions where flow occurs in fractures and in the blocks 

between fractures. Many tests in Butte Valley and the Tule 

Lake, Lower Klamath Lake, Sprague River, and upper Lost 

River subbasins showed inflections in drawdown curves, 

suggesting the presence of no-flow boundaries. These no-flow 

boundaries were in some cases associated with faults. Such 

boundaries indicate that the Tertiary volcanic aquifer system 

is, at least locally, somewhat compartmentalized, with some 

resistance to flow between individual subregions. Some tests 

showed evidence of recharge boundaries. Recharge boundaries 

usually indicate that the cone of depression has expanded 

to an extent where it has intersected a source of recharge, 

for example a stream or canal. Given the stratigraphy of the 

areas tested, the pumping more likely was inducing flow 

from the overlying low-permeability sediments. Tests that 

showed evidence of recharge boundaries or leaking confining 

layers occurred in the Lower Klamath Lake and Lost River 

subbasins. Inflections in drawdown curves can also be caused 

by double porosity conditions (Moench, 1984; Weeks, 2005).

Geologic Framework 13
Table 2. Summary of selected aquifer tests, upper Klamath Basin, Oregon and California.

[SWL, datum and date not always available. Static level listed to provide information on saturated thickness open to well. Open interval, may be a composite of multiple open intervals. Aquifer unit, Aquifer unit descriptions in figure 4. Observation wells, includes only number of observation wells used in analysis. Transmissivity, Reported values rounded to two significant figures. Abbreviations: SWL, static water level; gal/min, gallons per minute; gpd/ft, gallons per day per foot; ft2/d, feet squared per day; (?), aquifer unit unclear; >, greater than; NA, not available]

Well or test name Well ID Location Area Depth SWL (feet) Open interval Aquifer unit Discharge (gal/min) Test length (hours) Drawdown (feet)

Hill KLAM 2021 36S/11E-35DCC Sprague River subbasin 384 37.16 120–384 Ts 2,378 24 65.06Vieira KLAM 1962 36S/11E-14DBC Sprague River subbasin 361 -1.22 100.5–361 Tv/Ts 1,455 79 21.95OIT KLAM 10390 38S/9E-20BAD Klamath Falls 1,675 238.6 946–1,675 Ts/Tv(?) 900 48 3.5City of Klamath Falls KLAM 12050 38S/9E-28DCB Klamath Falls 900 64 190–900 Ts 720 499 10Angel KLAM 12380 38S/11.5E-2DCB Yonna Valley 583 69.63 31–583 Tv 1,700 24 5Bonanza KLAM 13427 39S/11E-20AAD Bonanza 567 66.19 20–567 Tv 938 12 55.13Wright KLAM 13578 39S/12E-31ADD Bonanza 292 15 20–292 Tv 1,430 40 NAListon KLAM 13583 39S/12E-32CDB Bonanza 245 43.72 39–245 Tv 940 41 NABabson KLAM 51920 39S/12E-10ACA Bonanza >2,056 21 500–>2,056 Tv 6,800 722 274

S. Langell Valley KLAM 10495 40S/13E-35DAA Langell Valley 287 8.47 269–287 Tv 2,034 24 8.32Lorella KLAM 10175 39S/12E-35AAB Lorella 465 98 171–465 Tv 1,404 24 NA

Poe Valley KLAM 10292 39S/11.5E-26DBA South Poe Valley 292 44.28 39–292 Tv 3,338 24 38.45Malin KLAM 14821 40S/12E-28DCB Malin 647 202.85 19–647 Tv/Ts 975 12 13.3Silbernagel/Dark KLAM 10454 40S/12E-32BCB North of Malin 629 140 41–629 Tv 1,416 70.5 >16McVay KLAM 51062 40S/12E-32DCB North of Malin 455 142 19–455 Tv 1,290 4,056 17CDFG 7A CDWR 421225 47N/2W-27BAA Butte Valley 601 21.41 160–610 Tv 2,800 244.5 16USFWS 12-A Prod. NA 47N/3E17DDD Lower Klamath Lake 1,254 28.1 400–1,254 Ts 3,000 48 190.7USFWS 9-A NA 47N/3E-16BDC Lower Klamath Lake 600 23.1 410–600 Tv 6,200 48 23.4USFWS 9-C NA 47N/3E-16ABA Lower Klamath Lake 802 28.7 516–802 Tv/Ts 7,300 26 27.4USFWS Otey Island NA 48N/1E-23B Lower Klamath Lake 334 26.3 142–334 Tb 6,000 36 17.6USFWS Otey Island NA 48N/1E-23B Lower Klamath Lake 625 5.3 142–625 Tv 4,000 72 23USFWS Stearns NA 48N/3E-20BAD Lower Klamath Lake 1,478 72.4 300–1,478 Tv 2,500 72 127TID-1 CDWR 751108 48N/4E-30F02 Tule Lake subbasin 740 19.91 260–700 Tv 9,000 50 11.37TID-2 CDWR 751109 48N/4E-18J01 Tule Lake subbasin 1,550 34.22 1,260–1,540 Tv 10,500 21 67.65

TID-3 CDWR 751110 48N/4E-16M01 Tule Lake subbasin 1,710 42.17 1,153–1,681 Tv 8,000 33 98.52

TID-4 CDWR 751111 48N/4E-15K01 Tule Lake subbasin 1,440 27.77 1,212–1,433 Tv 9,500 48 82.52

TID-5 CDWR 751112 48N/4E-13K01 Tule Lake subbasin 1,570 29.64 935.2–1,557 Tv 10,500 74 96.94

TID-6 CDWR 751113 48N/5E-16P01 Tule Lake subbasin 2,600 33.85 823–2,358 Tv 4,000 59 92.74

TID-7 CDWR 751114 48N/5E-14R01 Tule Lake subbasin 2,030 50.92 814.3–2,020 Tv 5,000 52 264.59

TID-8 CDWR 751115 48N/5E-26D01 Tule Lake subbasin 1,810 32.32 1,250–1,802 Tv 3,935 27 264.59

TID-9 CDWR 751116 48N/5E-36D01 Tule Lake subbasin 2,060 34.66 1,061–2,023 Tv 6,600 16 173.57

TID-14 CDWR 751117 46N/5E-22D01 Tule Lake subbasin 571 21.4 114–554 Tv 9,500 48 24.43

14 Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California
Remarks:

1. Results of one observation well not included because of possible effects of upper Klamath Lake.2. 15 observation wells explicitly discussed in report, additional wells used in anaysis, 52 wells were monitored. Transmissivity value assumes 1,000-foot aquifer thickness. Geothermal aquifer.3. Results from one observation well (9A) not included here because of differences in well construction and depth.4. Results from one observation well (9C) not included here because of differences in well construction and depth.

5. Only results from one observation well (9C) included here.6. Only results of drawdown analysis included here.7. Only results from production well included here.8. Only results from observation wells presented here.9. Large range may result from inefficiency of production well.

Well or test name Well ID Observation wells Transmissivity (gpd/ft) Transmissivity (ft2/d) Storativity Remarks Source

Hill KLAM 2021 1 190,000–530,000 25,000–71,000 0.002–0.0057 Almy, 1977

Vieira KLAM 1962 5 180,000–560,000 24,000–75,000 0.00026–0.0033 Forcella, 1982

OIT KLAM 10390 5 100,000–280,000 13,000–37,000 0.015–0.00034 1 William E. Nork, Inc, 1992City of Klamath Falls KLAM 12050 15 28,000 3,800 0.002 2 Benson and others, 1984a, 1984bAngel KLAM 12380 0 2,000,000 270,000 NA Leonard and Harris, 1974

Bonanza KLAM 13427 1 140,000–180,000 19,000–24,000 0.00045 CH2M Hill, 1992Wright KLAM 13578 3 130,000 17,000 NA CH2M Hill, 1994

Liston KLAM 13583 1 20,000–91,000 2,700–12,000 NA CH2M Hill, 1994

Babson KLAM 51920 0 480,000–620,000 64,000–83,000 NA CH2M Hill, 2002

S. Langell Valley KLAM 10495 2 4,500,000 600,000 0.00025 Grondin, 2004Lorella KLAM 10175 1 370,000 50,000 0.0003 Grondin, 2004Poe Valley KLAM 10292 1 1,100,000 150,000 0.0004 Grondin, 2004Malin KLAM 14821 0 190,000 25,000 NA CH2M Hill, 1992

Silbernagel/Dark KLAM 10454 2 120,000–200,000 16,000–27,000 0.0003–0.01 Gates, 2001

McVay KLAM 51062 4 200,000 27,000 0.001 Zwart and Gates, 2002CDFG 7A CDWR 421225 7 2,200,000–4,600,000 300,000–610,000 0.001–0.002 California Department of Water 

Resources, 1998

USFWS 12-A Prod. NA 1 2,200,000–2,600,000 300,000–350,000 0.00005–0.0001 3 Golder Associates, Inc., 2002

USFWS 9-A NA 1 180,000–440,000 24,000–59,000 0.04 4 Golder Associates, Inc., 2002USFWS 9-C NA 1 820,000 110,000 0.0002 5 Golder Associates, Inc., 2002USFWS Otey Island NA 0 3,100,000 420,000 NA 6 Golder Associates, Inc., 2002

USFWS Otey Island NA 1 3,700,000 500,000 NA WESCORP, 2003

USFWS Stearns NA 0 58,000 7,700 NA 7 WESCORP, 2003

TID-1 CDWR 751108 1 650,000–1,200,000 87,000–160,000 0.15 Eaves and others, 2002TID-2 CDWR 751109 1 1,300,000–3,100,000 170,000–410,000 0.001 Eaves and others, 2002TID-3 CDWR 751110 0 2,300,000 310,000 NA Eaves and others, 2002

TID-4 CDWR 751111 0 1,100,000 150,000 NA Eaves and others, 2002

TID-5 CDWR 751112 1 2,000,000 270,000 0.002 Eaves and others, 2002TID-6 CDWR 751113 2 120,000–190,000 16,000–25,000 0.00006–0.00012 Eaves and others, 2002

TID-7 CDWR 751114 0 51,000 6,800 NA Eaves and others, 2002

TID-8 CDWR 751115 2 1,700,000–1,900,000 230,000–250,000 0.00001–0.00052 8 Eaves and others, 2002

TID-9 CDWR 751116 1 700,000–2,900,000 94,000–390,000 0.00017 9 Eaves and others, 2002

TID-14 CDWR 751117 0 2,600,000 350,000 NA Eaves and others, 2002

Table 2. Summary of selected aquifer tests, upper Klamath Basin, Oregon and California—Continued.[SWL, datum and date not always available. Static level listed to provide information on saturated thickness open to well. Open interval, may be a composite of multiple open intervals. Aquifer unit, Aquifer unit descriptions in figure 4. Observation wells, includes only number of observation wells used in analysis. Transmissivity, Reported values rounded to two significant figures. Abbreviations: SWL, static water level; gal/min, gallons per minute; gpd/ft, gallons per day per foot; ft2/d, feet squared per day; (?), aquifer unit unclear; >, greater than; NA, not available]

Geologic Framework15
Aquifer tests show that the transmissivity of the Tertiary 

volcanics (predominantly basaltic lavas) varies widely, 

from 2,700 to 610,000 ft2/d, with most (the middle 50 

percent) ranging from 24,000 to 270,000 ft2/d. The average 

transmissivity is about 170,000 ft2/d and the median is about 

90,000 ft2/d. Reported storage coefficients from aquifer tests 

in the Tertiary volcanics range from 0.00001 to 0.15. The 0.15 

figure is anomalous and likely due to a partially penetrating 

observation well and leakage from the confining layer. The 

middle 50 percent of the calculated storage coefficients in the 

Tertiary volcanics range from 0.00025 to 0.001. The average 

value is 0.0012 and the median is about 0.0005.

Although the number of aquifer tests in Tertiary 

sediments (or mixtures of the sediments and Tertiary lavas) 

is small (n=6, not including the geothermal aquifer test), they 

provided information on the hydraulic characteristics of the 

coarse-grained facies of unit Ts. Transmissivity values range 

from 13,000 to 350,000 ft2

/d, with most in the 25,000 to 

75,000 ft2/d range. The average value is about 100,000 ft2/d 

and the median is 54,000 ft2/d. Storage coefficients range 

from 0.0005 to 0.015 with most ranging from about 0.0002 to 

0.003. Note that most Tertiary sedimentary rock in the basin 

consists of fine-grained lake deposits and has much lower 

transmissivity than determined from the tests discussed here.

In the early 1980s, the USGS conducted an aquifer test of 

the geothermal aquifer in Klamath Falls in collaboration with 

the Lawrence Berkeley Laboratory and the City of Klamath 

Falls (Benson and others, 1984a, b). The test consisted of four 

phases: a 1-week pre-test phase during which background 

water levels were monitored; a 21-day pumping phase during 

which a geothermal well (38S/09E-28DCB, KLAM 12050; 

table 2) was pumped at about 720 gal/min and the water 

discharged to an irrigation canal; a 30 day injection phase 

during which pumping continued (at about 660–695 gal/min) 

and the water injected into a second well (38S/09E-28DDD, 

KLAM 11940); and a 1-week recovery phase. Benson and 

others (1984a) analyzed the data from the test and calculated 

a permeability-thickness value (analagous to a transmissivity) 

of about 1.4 X 106

 millidarcy-feet. This converts to a 

transmissivity of about 3,800 ft2

/d. Analysis of the test 

indicated a storage coefficient of about 0.002.

Results of the geothermal aquifer test are generally 

consistent with the other aquifer tests in table 2. The 

transmissivity value is at the lower end of the range of other 

tests, but this is not unexpected as the aquifer system pumped 

consists of interlayered lava and fine-grained sedimentary rock 

(unit Ts). A notable finding of this test is the apparent lack of 

boundaries encountered in an area crossed by several major 

basin-bounding faults. This is not, however, inconsistent with 

other hydrologic data that suggest ground water moves freely 

across similar faults at many locations.

Well-Yield Tests

Another source of information on subsurface hydraulic 

characteristics are the well-yield tests conducted by drillers 

and reported on the well logs submitted on completion 

of all new wells. Well-yield tests typically consist of a 

single drawdown measurement taken after a well has been 

pumped at a specified rate for a specified length of time, 

typically 1 hr. Well-yield tests allow determination of a 

well’s specific capacity, which can be used to estimate 

transmissivity as described previously. Specific capacity 

is only a semiquantitative measure of well performance in 

that it can vary with pumping rate. Specific-capacity values 

can be used to calculate only rough estimates of the aquifer 

transmissivity and cannot be used to quantitatively derive 

aquifer storage characteristics. Although transmissivity values 

calculated from specific capacity tests are only approximate, 

they can be used to evaluate the relative differences in 

hydraulic characteristics between different geographic areas 

and different hydrogeologic units if data are available from a 

sufficient number of wells.

Specific-capacity data were analyzed from wells that 

were field inventoried for this study. Of the over 1,000 wells 

inventoried, only about 288 had sufficient information for 

analysis on their State water well reports. Transmissivity 

values were estimated from specific-capacity data using the 

Theis nonequilibrium equation (Theis, 1935). The wells 

analyzed were sorted by hydrogeologic units for comparison. 

Most wells analyzed produced from one of three units: 

Quaternary sedimentary deposits (Qs) (n = 41), Tertiary 

sedimentary rocks (Ts) (n = 48), and late Tertiary volcanic 

deposits (Tv) (n = 173). Other units had too few tests for 

statistically meaningful comparisons. The cumulative 

frequencies of transmissivity estimates for the three major 

units are shown in figure 5. Wells producing from Quaternary 

sedimentary deposits and Tertiary sedimentary deposits 

have similar transmissivity distributions, with the former 

having slightly larger values. The median transmissivity 

for both units is about 200 ft2

/d. The frequency distribution 

of transmissivities for the late Tertiary volcanic deposits is 

distinct from the other units, with values generally larger 

by more than an order of magnitude (fig. 5). The median 

transmissivity of Tertiary volcanic deposits is about 

5,800 ft2

/d.

The median transmissivity for late Tertiary volcanic 

deposits determined from specific-capacity tests (6,300 ft2/d) 

is lower than that calculated from aquifer tests (about 

90,000 ft2/d). This is not unexpected for the following reasons: 

First, transmissivity values determined from single-well tests 

can be biased downward by excess drawdown in the pumped 

well due to well inefficiency (see Driscoll, 1986, p. 244). 

16 Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California
Aquifer tests with observation wells are not affected by this 

phenomenon. Second, the large number of specific-capacity 

tests (173) represent a more or less random sampling of 

wells (and varying characteristics) in the unit. Aquifer tests, 

in contrast, are not random but tend to be conducted most 

commonly on high yielding wells for specific purposes. 

Regardless, transmissivity values calculated from both aquifer 

tests and specific-capacity tests are useful for understanding 

the hydraulic characteristics of hydrogeologic units and the 

differences between units.

Ground-Water Hydrology

Ground water moves from areas where it enters the 

ground, known as “recharge areas,” to areas where it leaves 

the ground, known as “discharge areas.” On a regional scale, 

recharge areas are typically high-elevation regions with large 

amounts of precipitation compared to surrounding areas. 

Ground water moves from recharge areas toward low-elevation 

areas in response to gravity. In low-elevation areas, ground 

water typically discharges to streams, lakes, or wetlands and 

then is returned to the atmosphere through evapotranspiration 

or leaves the basin as streamflow. Ground water can be 

removed anywhere along its flow path by wells.

Ground water moves in response to differences in 

hydraulic head, from areas of high head to areas of low 

head. In unconfined aquifers—those without overlying lowpermeability strata—hydraulic head can be thought of as the 

elevation of the water table. In confined aquifers, hydraulic 

head can be thought of as the elevation of the aquifer plus the 

pressure of the confined ground water. Maps of hydraulic head 

are useful for identifying recharge and discharge areas, and 

for indicating the direction of ground-water flow. Although 

the regional scale movement of ground water largely follows 

topography, the actual flow paths that the ground water 

follows and the rate of ground-water movement is controlled 

by the permeability of the geologic materials through which 

it flows. The rate of ground-water movement is proportional 

to the hydraulic head gradient and the permeability of the 

geologic materials.

Ground-water systems are dynamic, with rates of 

recharge and discharge and hydraulic head varying in 

response to external stresses. The largest external influence on 

ground-water systems is climate. Drought cycles cause large 

fluctuations in recharge, ground-water levels, and discharge to 

springs and streams. Human-caused stresses, such as pumping 

and artifical recharge from canal leakage and deep percolation 

of irrigation water, also affect the ground-water system.

OR19-0048_fig05

0

10

20

30

40

50

60

70

80

90

100

PERCENTILE

0.1 1 10 100 1,000 10,000 100,000 1,000,000

TRANSMISSIVITY, IN FEET SQUARED PER DAY

Qs, n = 41

Ts, n = 48

Tv, n = 173

Figure 5. Cumulative distribution of transmissivity values estimated from specific-capacity tests for wells producing 

from Quaternary sediment, Tertiary sedimentary rock, and Tertiary volcanic rock in the upper Klamath Basin, Oregon 

and California.

Ground-Water Hydrology 17
Hydrologic Budget

The hydrologic budget is the accounting of water moving 

into and out of a hydrologic system such as the upper Klamath 

Basin. A general hydrologic-budget equation is:

PRECIP + SWin + GWin = ET + SWout + GWout + ∆S, (1)

Where

PRECIP is precipitation,

SWin is the inflow of surface water,

GWin is the subsurface inflow of ground water,

ET is total evapotranspiration,

SWout is the out flow of surface water,

GWout is the subsurface outflow of ground water, and

∆S is the change in water stored in the surface- and 

ground-water systems.

These individual terms may have multiple components. 

For example, ET includes the evapotranspiration from forests, 

wetlands, and agricultural crops. In the upper Klamath Basin, 

the largest terms are PRECIP, ET, and SWout. There is no 

evidence of subsurface ground-water flow into the basin 

(GWin). Ground-water flow out (GWout) toward the south is 

probable, but the amount is likely to be miniscule compared 

to other terms in the equation. The storage term (∆S) includes 

both surface storage in reservoirs and subsurface storage 

of ground water in aquifers. When dealing with long-term, 

multiyear averages, changes in surface water storage are 

commonly negligible.

Long-term changes in ground-water storage are manifest 

as year-to-year changes in the water-table elevation. Longterm observation well data indicate that a slight, climaterelated decline has taken place in water levels in wells in the 

Klamath Basin since the 1950s. The magnitude of the decline 

varies spatially, but ranges from zero to about 10 ft over 50 

years. Larger declines have been measured near pumping 

centers, but are generally geographically restricted. The 

amount of water represented by the annual change in groundwater storage is small compared to the overall hydrologic 

budget. For example, assuming the change in storage occurred 

in the shallow, unconfined parts of the system and using 

a storage coefficient of 0.05 (a reasonable number for an 

unconfined volcanic aquifer), a decline of 5 ft in 50 years 

averaged over the entire 8,000 mi2

 upper Klamath Basin 

equates to an annual change in storage of about 26,000 acre-ft.

Some components of a hydrologic budget, such as 

streamflow, can be measured directly. Other components, 

such as evapotranspiration, are impractical or impossible to 

measure directly at useful scales and must be estimated or 

inferred from other measurements. This section presents a very 

general discussion of the hydrologic budget of the entire upper 

Klamath Basin (summarized in table 3) to provide a context 

for a more detailed discussion of the hydrologic budget of the 

ground-water system. All figures presented in this section have 

associated uncertainty.

Data from the Oregon Climate Center PRISM Group 

(http://www.ocs.oregonstate.edu/prism/index.phtml, accessed 

September 20, 2006) indicates that precipitation in the upper 

Klamath Basin averages about 10 million acre-ft/yr (1971–

2000 average). Of that amount, only about 1.5 million acreft/yr flows out of the basin past Iron Gate Dam (1961–2000 

average; 1971–2000 average is 1.6 million acre-ft/yr). Most of 

the remaining 8.5 million acre-ft/yr returns to the atmosphere 

through evapotranspiration at the location where the 

precipitation falls. Some of the 8.5 million acre-ft/yr, however, 

returns to the atmosphere elsewhere in the basin after it has 

moved through the hydrologic system. An example of the 

latter case would be water diverted from streams or pumped 

from ground water that returns to the atmosphere through 

evapotranspiration from irrigated fields (this type of loss is 

often termed “consumptive use”). A small amount of water is 

exported from the basin. La Marche (2001) estimated water 

exports to the Rogue River Basin to average 0.027 million 

acre-ft/yr between 1960 and 1996

Burt and Freeman (2003) estimated that 

evapotranspiration from agricultural fields in the Klamath 

Project in 1999 and 2000 averaged 0.48 million acre-ft/yr 

(the 2001 estimates are not included here because of the 

cut off of irrigation water that year). Estimates by Cooper 

(2004) suggest that average annual agricultural consumptive 

use in the principal agricultural areas outside of the Klamath 

Project in Oregon (including the Williamson, Sprague, and 

Wood River subbasins) totals about 0.2 million acre-ft/yr. 

Consumptive use by ground-water irrigated agriculture outside 

of the Klamath Project in California (including areas in the 

Tule Lake and Butte Valley subbasins) is estimated to be about 

0.072 million acre-ft/yr on the basis of data from the CDWR 

2000 land use survey. Areas irrigated with surface water in 

California outside of the Project are small in comparison to 

ground-water irrigated areas and are not included in this total. 

There is also significant evapotranspiration from wetlands 

and open water in the upper Klamath Basin. Hubbard (1970) 

estimated that evapotranspiration from open water and the 

fringe wetlands of Upper Klamath Lake averaged 0.29 million 

acre-ft/yr from 1965 to 1967. Risley and Gannett (2006) 

estimated that evapotranspiration from the Tule Lake and 

Lower Klamath Lake refuges totaled about 0.22 million acreft/yr from 2003 to 2005. Average evapotranspiration in the 

Klamath Marsh area was estimated to be about 0.17 million 

acre-ft/yr using the method of Priestly and Taylor (1972) (Tim 

Mayer, U.S. Fish and Wildlife Service, written commun., 

2005). Burt and Freeman (2003) estimated evapotranspiration 

from other surfaces in the Project area, including open water 

outside of refuges, urban areas, and undeveloped land to 

average about 0.082 million acre-ft/yr in 1999 and 2000. 

18 Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California
The source documents listed above all discuss uncertainty of 

the evapotranspiration estimates in general terms. Bert and 

Freeman (2003), however, provide a quantitative uncertainty 

assessment, and assign confidence intervals of plus or minus 

14 to 20 percent for the estimates discussed here. Although 

the above list of evapotranspiration losses, which totals 1.5 

million acre-ft/yr, is not exhaustive, it includes the bulk of 

consumptive uses in the nonupland parts of the basin. When 

this number is added to the streamflow out of the basin, about 

7 million acre-ft/yr of precipitation (about 70 percent of the 

total precipitation) still leaves the basin through other avenues, 

principally as evapotranspiration to the atmosphere in upland 

areas.

A substantial proportion of the roughly 3 million 

acre-ft/yr that leaves the basin through streamflow or 

evapotranspiration in nonupland areas moves through the 

regional ground-water system. Equation 1 describes flow into 

and out of the entire upper Klamath Basin. Most flow into and 

out of the regional ground-water system occurs entirely within 

the basin. The hydrologic budget of the regional ground-water 

system can be described by the equation:

RECH + GWin = GWdis + GWout + ∆S, (2)

where

RECH is ground-water recharge, and

GWdis is ground-water discharge.

The largest terms in equation 2 are RECH and GWdis. 

Recharge (RECH) includes infiltration of precipitation, 

leakage from streams and canals, and deep percolation of 

irrigation water. Ground-water discharge (GWdis) includes 

natural discharge of ground water to springs and streams, 

water consumed by plants with their roots extending to the 

water table, and by pumping of wells. A schematic depiction 

of a ground-water flow system is shown in figure 6.

Table 3. Estimates of major hydrologic budget elements of the upper Klamath Basin, Oregon and California.

[ET, evapotranspiration; values in million acre feet per year; PRISM, Parameter-elevation Regressions on Independent Slopes Model (Oregon State University, 

PRISM Group, 2006); CDWR, California Department of Water Resources; USFWS, U.S. Fish and Wildlife Service; USGS, U.S. Geological Survey]

Budget element Value Source and remarks

Inflow

Precipitation 10 1971–2000 average from PRISM

Subsurface inflow unknown Assumed to be negligible

Total inflow 10

Outflow

Subsurface outflow unknown Assumed to be negligible

Surface outflow at Iron Gate Dam 1.5 1961–2004 annual average (USGS gage data)

Net diversions to other basins .03 1960–1996 annual average from LaMarche (2001). Does not 

include diversion to City of Yreka from Fall Creek

ET from agricultural lands

Bureau of Reclamation Klamath .48 1999 and 2000 average (Burt and Freeman, 2003)

Non-Project land in Oregon .20 Cooper (2004)

Non-Project land in California .07 Estimated from CDWR 2000 land-use survey

ET from major wetlands

Tule Lake and Klamath Refuge (not including open water) .22 2003–05 average (Risley and Gannett, 2006)

Upper Klamath Lake fringe wetlands .29 1965–67 average (Hubbard, 1970)

Klamath Marsh .17 Estimated using the method of Priestly and Taylor (1972) (Tim 

Mayer, U.S. Fish and Wildlife Service, written commun., 

2005)

ET from nonagricultural areas within the Klamath Project .08 1999 and 2000 average (Burt and Freeman, 2003)

Subtotal outflow 3.0

Estimated ET from nonagricultural and upland areas outside 

the Project

7.0 Total inflow minus outflow subtotal

Total outflow 10

Ground-Water Hydrology 19
Ground-Water Recharge

Ground water originates as precipitation. Recharge is 

generally greatest in upland areas where the largest amount of 

precipitation occurs. The principal recharge areas in the upper 

Klamath Basin are the Cascade Range and uplands within and 

on the eastern margin of the basin. Only a fraction of the water 

that falls as precipitation, however, makes it to the groundwater system. Most either is returned to the atmosphere 

through evaporation from vegetative surfaces and transpiration 

by plants, or runs off. In areas where soils and underlying 

bedrock have low permeability, infiltrating precipitation tends 

to flow to streams. Such areas typically have well developed 

stream networks. In areas where soils and underlying bedrock 

are highly permeable, for example the young volcanic 

landscapes of the Cascade Range, water infiltrates more easily 

to the ground-water system. Young volcanic areas often have 

poorly developed stream networks as a result. Water that 

percolates through the soil to a depth beneath the root zone 

potentially can become ground water.

Although direct infiltration of precipitation is the 

principal source of recharge in the upper Klamath Basin, there 

are other sources. Stream leakage can be a source of groundwater recharge in areas where the elevation of the stream is 

higher than the water table and the streambed is permeable. 

For example, streams that enter the Klamath Marsh area 

from the Cascade Range in the northern part of the study 

area generally lose much or all of their flow into the highly 

permeable soil as they flow onto the pumice plain. No major 

streams in the upper Klamath Basin, however, are known to 

lose regionally significant water in this manner, and stream 

leakage probably is not a substantial source of recharge on a 

regional scale in the basin.

Irrigation activities also can result in artificial groundwater recharge. Irrigation canals typically lose some 

water to the shallow parts of the ground-water system. 

No measurements of canal leakage rates in the upper 

Klamath Basin were available or made during this study, 

but measurements exist for other areas. Canal leakage rates OR19-0048_fig06.ai

Water table

Water table

Recharge fromprecipitation

Recharge from precipitation

Recharge from precipitation

Discharge to stream(local flow system)

Discharge to stream(regional flow system)

Regional flow system

Local 

flow system

Intermediate 

flow system

Shallow local 

flow system

Subsurface flow 

to adjacent basins

 (Discharge)

Subsurface flow 

from adjacent basins (Recharge)

Discharge to subirrigation in areas of shallow ground waterDischarge to wellsRecharge from precipitationand deep percolation of irrigation waterDischarge to drainsRecharge from canal leakage

Discharge to spring

Spring

Lava with moderate to high permeability

Basin filling sedments

(Low permeability with 

some moderate permeability layers)

NOT TO SCALE

RECHARGE = DISCHARGE ± CHANGE IN AQUIFER STORAGE Fault

Fault

Fault

Figure 6. Schematic representation of sources of ground-water recharge, flow paths, and mechanisms of ground-water discharge in 

the upper Klamath Basin, Oregon and California.

20 Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California
determined from ponding studies range from less than 1 

to greater than 20 (ft3/s)/mi in the upper Deschutes Basin, 

directly to the north of the Klamath Basin (Gannett and others, 

2001). The large rates are from unlined canals in fractured 

lava. Rates in areas underlain by sedimentary deposits 

commonly range from less than 1 to 3 (ft3/s)/mi. Canal leakage 

rates in the Methow Valley of Washington range from 1.0 

to 10.7 (ft3/s)/mi, and average 1.8 (ft3/s)/mi (Konrad, 2003). 

Canal bed materials there include glaciofluvial deposits, 

colluvium, clay, and bedrock. In addition to canal leakage, 

water applied to fields can percolate beneath the root zone 

and into the shallow parts of the ground-water system. The 

amount of deep percolation of irrigation water depends on 

the irrigation method. Gannett and others (2001) estimated 

ground-water recharge from deep percolation of irrigation 

water in the upper Deschutes Basin to be about 49,000 acreft/yr, or about 11 percent of the estimated water deliveries. 

Studies in the Amargosa Desert in Nevada resulted in 

estimates of deep percolation ranging from 8 to 16 percent 

of applied water (Stonestrom and others, 2003). No data are 

available to determine the amount of ground-water recharge 

from canal leakage and deep percolation of irrigation water 

in the upper Klamath Basin. However, ground-water recharge 

from irrigation activities is indicated because the water table 

in the shallow aquifers in the Project area rises during the 

irrigation season, and 2001 measurements showed the shallow 

water table declined when irrigation was severely curtailed in 

the Project area. Moreover, some deep irrigation wells also 

respond when canals of the Klamath Project start flowing 

in the spring (Bill Ehorn, California Department of Water 

Resources, written commun., 2002), indicating some recharge 

takes place, at least locally, to the deeper parts of the groundwater system from irrigation-related activities. Most irrigation 

in the upper Klamath Basin occurs in alluvial stream valleys 

and lake basins, and these areas are commonly crisscrossed 

by drains. Much of the water recharged to the shallow parts of 

ground-water system by irrigation activities likely discharges 

to the drain system (or streams) after traveling underground 

only a short distance (probably less than thousands of feet). 

Data are insufficient to estimate net regional ground-water 

recharge from irrigation activities in the upper Klamath 

Basin; however, the low permeability of the lake sediments 

that underlie most of the Klamath Project area suggests that 

ground-water movement from the water table in the Project 

area to the deeper, regional ground-water system is somewhat 

restricted and that canal leakage and deep percolation of 

irrigation water probably are not a significant source of 

recharge to the regional ground-water system.

Ground-water recharge cannot be directly measured 

at a regional scale. Regional ground-water recharge can be 

estimated, however, by measuring ground-water discharge, 

which can be measured or estimated with reasonable accuracy. 

Equation 2 shows that ground-water recharge to a system is 

equal to the discharge plus or minus any changes in storage. 

The long-term change in ground-water storage in the upper 

Klamath Basin (as indicated by long-term water level data) 

is negligible compared to the annual ground-water budget, 

allowing recharge to be estimated by measuring or estimating 

components of discharge.

The principal avenues of ground-water discharge 

in the upper Klamath Basin are discharge to streams, 

evapotranspiration by plants with roots that penetrate to the 

water table (in a process known as “subirrigation”), and 

pumping. Ground-water discharge to streams is estimated to 

average about 1.8 million acre-ft/yr, or about 2,400 ft3

/s.

Ground-water pumping in 2000, prior to the rapid 

increase starting in 2001, is estimated to have been about 0.15 

acre-ft/yr. Ground-water discharge through subirrigation in 

areas where the water table is close to land surface is difficult 

to estimate because it often occurs in wetlands where water 

comes from both ground- and surface-water sources. Total 

evapotranspiration from Upper Klamath Lake and surrounding 

wetlands, the Tule Lake and Lower Klamath Lake Refuge 

wetlands, and Klamath Marsh is estimated to be roughly 0.7 

million acre-ft/yr (table 3), a large amount of this, however, is 

supplied by surface water. Therefore, ground-water discharge 

through subirrigation is likely small compared to discharge to 

streams.

Given that regional-scale long-term changes in groundwater storage are small, average recharge to the regional 

ground-water system is assumed to be approximately equal 

to the estimated ground-water discharge to streams and wells 

of about 2 million acre-ft/yr (rounded up to reflect some 

evapotranspiration directly from the water table). This figure 

does not include recharge from irrigation activities in the 

Project or subsurface discharge to or recharge from adjacent 

basins.

Ground-water recharge from precipitation, therefore, 

is about 20 percent of the total precipitation basinwide. The 

exact percentage, however, varies spatially and temporally. 

Gannett and others (2001), working with a water-balance 

model developed by Boyd (1996), noted that ground-water 

recharge in the upper Deschutes Basin ranges from 5 to 70 

percent depending on location. In the Cascade Range, where 

there is a large amount of precipitation, which far exceeds 

potential evapotranspiration, a large percentage enters the 

ground-water system. In contrast, only a small fraction of the 

precipitation recharges ground water in the very dry interior 

parts of the basin, where precipitation is a fraction of the 

potential evapotranspiration. Temporally, recharge varies 

seasonally and from year to year. Recharge from precipitation 

in mountainous areas, like the Cascade Range, occurs during 

spring snowmelt. Recharge from irrigation occurs during the 

irrigation season. The timing of recharge pulses from these 

sources can be seen in water level data from wells (discussed 

later). Recharge will vary from year to year depending on 

the annual precipitation. Estimated basinwide recharge in the 

upper Deschutes Basin ranged from less than 3 in/yr during 

the drought years of 1977 and 1994 to more than 20 in/yr in 

1982 (Gannett and others, 2001).

Ground-Water Hydrology 21
Ground-Water Discharge to Streams

Water flows to streams through a variety of mechanisms. 

For convenience, streamflow is often broken into three 

components: surface runoff, interflow, and baseflow. The 

surface runoff component reaches the stream through 

overland flow or flow in the top of the soil profile. Such 

flow is typically rapid, and is responsible for the rapid rise in 

streamflow during and immediately after storms or snowmelt. 

Interflow, also termed subsurface runoff, reaches the stream 

through flow in unsaturated or temporarily saturated zones 

in the upper soil layers. Baseflow generally is considered to 

be fed by ground-water discharge. Baseflow can originate 

from a variety of scales of ground-water flow, ranging from 

short, local flow paths to long and deep regional flow paths. 

Baseflow generally is the source of water in streams in the late 

summer and fall, when little or no precipitation or remaining 

snow are available to provide surface runoff or interflow.

The flow in some streams in the upper Klamath Basin 

consists entirely of ground-water discharge. Such streams 

are characterized by consistent year-round flow with little 

seasonal variability. An example of a typical ground-water-fed 

stream is the Wood River at Fort Klamath (USGS streamgaging station number 11504000), which during the period of 

record from 1913 to 1936 had a mean annual flow of 215 ft3

/s 

and a standard deviation of daily mean flows of only 58 ft3/s. 

The mean September flow of the Wood River was 199 ft3/s, or 

about 93 percent of the mean annual flow. Other streams, in 

contrast, have a relatively small component of ground-water 

discharge and consist predominantly of surface runoff. Such 

streams have large seasonal variability, with high flows during 

and immediately after rainfall or snowmelt followed by low 

or no flow during the dry periods of the year. Stream gaging 

data from the Sycan River below Snake Creek near Beatty 

(station 11499100) provide an example of a stream with a 

large component of surface runoff. During the period of record 

from 1973 to 2003 the Sycan River at this location had a mean 

annual flow of 152 ft3

/s and a standard deviation of daily mean 

flows of 282 ft3

/s. The mean September flow of the Sycan 

River here is only 23 ft3/s, or about 15 percent of the mean 

annual flow. Most streams in the Klamath Basin exhibit all 

three components of discharge throughout the year. Identifying 

the amount of streamflow supplied by ground-water discharge 

is problematic during times of the year when there is 

substantial contribution from overland flow and interflow. 

However, in the late summer and fall, when there is scant 

precipitation and snow has melted, streamflow is composed 

largely of ground-water discharge. Exceptions to this 

generalization include streams receiving substantial irrigation 

return flow or water from reservoir releases. Where these 

exceptions do not occur, or can be accounted for, streamflow 

during the fall months (September–November) when 

precipitation, runoff, and interflow are nearly absent provides 

a good estimate of baseflow or ground-water discharge.

The location and quantity of ground-water discharge 

entering the stream network was estimated at numerous 

locations throughout the upper Klamath Basin (table 6, at 

back of report). Estimates are, for the most part, based on 

measurements of actual spring discharge or streamflow during 

late summer and fall. For some spring-dominated streams 

(Spring Creek, for example), streamflow over the entire year 

could have been used to determine ground-water discharge. 

However, to maintain consistency in the analysis, data from 

the fall months were used exclusively where possible. Some 

of the ground-water discharge estimates were based on the 

OWRD natural streamflow analysis for the Klamath Basin 

(Cooper, 2004). These estimates represent the median or 

typical flow for a particular month over a 30-year base period, 

from 1958 to 1997. For this study, the work was supplemented 

by additional analysis, streamflow measurements, and 

fieldwork performed from 1997 to 2005. When possible, the 

estimate represents the typical ground-water discharge for the 

fall over a base period from 1958 to 1987. Selection of this 

base period is detailed in Cooper (2002). However, sometimes 

the available data at a location was insufficient to generate an 

estimate that represented the base period. In those cases, the 

estimate may not reflect the long-term average conditions. The 

data sources and techniques used to estimate ground-water 

discharge are listed for each reach in table 6.

Estimates of ground-water discharge have inherent 

uncertainty. One source of uncertainty is the streamflow 

measurements on which they are based. For example, records 

from stream gages are rated “excellent” when 95 percent of 

the daily discharge values are within 5 percent of the true 

value, “good” when 95 percent of the daily discharge values 

are within 10 percent of the true value, and “fair” when 95 

percent of the daily discharge values are within 15 percent of 

the true value. Some of the estimates in table 6 are based on 

regression models where estimates are derived by comparing 

streamgage data that span periods that are short or outside of 

the base period, or miscellaneous measurements with longterm flow data from streams determined to be hydrologically 

representative of the stream in question. Regression models 

are another source of uncertainty. A detailed description of 

the regression analyses is available in Cooper (2004). Some 

ground-water discharge estimates in table 6 are based on 

single measurements or averages of multiple measurements 

and are not shifted to the base period. Consequently, there is 

uncertainty as to the degree to which they represent long-term 

average conditions. An assessment of the level of certainty 

of each estimate is included in table 6, and most figures are 

rounded to two significant figures. Rates of discharge at the 

large spring complexes responsible for most of the groundwater discharge in the basin are generally well known and 

have the least associated uncertainty. Although there may be 

uncertainty in the estimates of long-term average ground water 

discharging at certain locations, the presence of discharge 

at the listed locations is well established, and the general 

distribution and magnitude of ground-water discharge in the 

upper Klamath Basin is well understood.

22 Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California
Geographic Distribution of Ground-Water 

Discharge to Streams

Ground-water discharge to major streams was estimated 

in five subregions. The subregions were based on the USGS 

4th field Hydrologic Unit Code (HUC) with further analysis 

by smaller stream groupings in each subregion, based largely 

on 5th field HUCs. The five subregions are (1) Sprague River, 

(2) Williamson River, (3) Upper Klamath Lake, (4) Lost River, 

and (5) Klamath River.

The values in table 6 represent the estimated long-term 

average ground-water discharge (gains) to all major streams 

in the stream system, and therefore reflect most of the 

ground-water discharge to the streams. Average ground-water 

discharge into the stream network of the upper Klamath Basin 

(above Iron Gate Dam) totals about 2,400 ft3/s (1.8 million 

acre-ft/yr). This estimate includes gains to the Lost River, 

which are at least 195 ft3

/s, but may be higher due to unknown 

gains to the river below Lost River Diversion Channel. 

Ground-water discharge directly to Lower Klamath Lake and 

the Tule Lake Sump was not estimated due to insufficient data.

Ground-water discharge varies from subbasin to subbasin, 

reflecting precipitation patterns as well as geologic controls 

on ground-water movement (fig. 7). The largest groundwater discharge areas are in the Lower Williamson, Wood 

River, Upper Klamath Lake, and Klamath River subbasins. 

Besides Upper Klamath Lake and parts of the Klamath River 

subbasins, the specific locations of ground-water discharge are 

largely known and the quality of the estimates is considered 

good. Estimates of ground-water discharge to marshes have 

larger uncertainty due to difficulties with mass balances.

Temporal Fluctuations in Ground-Water 

Discharge to Streams

Ground-water discharge to streams is not constant, but 

fluctuates with time in response to variations in recharge and, 

in some circumstances, ground-water pumping. In the upper 

Klamath Basin, varying recharge is the predominant cause 

of ground-water discharge fluctuations. Recharge varies in 

response to seasonal weather patterns (wet winters versus dry 

summers), as well as in response to decadal-scale drought 

cycles and longer-term climate trends. A graph of total annual 

precipitation at Crater Lake National Park (fig. 8) shows 

the year-to-year variations in precipitation and longer-term 

variations. A useful way to look at long-term climate cycles 

is a graph of the cumulative departure from average (fig. 8). 

Water-table fluctuations and variations in discharge often 

mimic this pattern. The precipitation at Crater Lake over the 

past several decades exhibits the pattern observed at other 

precipitation stations throughout the region and in streamflow 

and ground-water levels as well. Most notable is the dry 

period in the 1930s and early 1940s followed by a wet period 

in the late 1940s and 1950s. The pattern from the 1960s to 

the present is characterized by decadal scale drought cycles 

superimposed on an apparent drying trend. Generally dry 

periods include 1966 to 1968, 1976 to 1981, 1987 to 1994, and 

2000 to 2005.

The timing and magnitude of ground-water discharge 

fluctuations can vary depending on the scale of the flow 

system involved. Small-scale systems with flow paths of less 

than a few miles and catchments of 1 to 10 mi2

, for example 

the flow system feeding the springs at the head of Annie 

Creek near Crater Lake, fluctuate in response to present-year 

precipitation. Such features will have large discharge during 

wet years and small discharge during dry years. In contrast, 

large-scale flow systems with flow paths of tens of miles and 

catchments of hundreds of square miles, such as the lowelevation regional spring complexes feeding the Wood River 

or Spring Creek, respond more to longer-term climate signals. 

Instead of reflecting the year-to-year precipitation like small 

springs, large-scale systems tend to integrate precipitation over 

several years and follow a pattern similar to the cumulative 

departure from average precipitation (fig. 8).

Several techniques were used in this study to determine or 

evaluate variations in ground-water discharge. Ground-water 

discharge fluctuations were in some cases measured directly 

by gaging stations on streams that are solely spring fed. Such 

data are rare in the upper Klamath Basin. Ground-water 

discharge fluctuations were calculated in some areas where 

two or more gaging stations with overlapping records bracket 

a stream reach to which ground-water discharges. These types 

of data are available for several stream reaches in the upper 

Klamath Basin. The analyses in such situations, however, 

were complicated by ungaged diversions or tributary inflow. 

Information on ground-water discharge fluctuations also was 

provided by sets of miscellaneous streamflow measurements 

along reaches where ground water discharges. Many streams 

include surface runoff as well as a large component of groundwater discharge. Comparing late summer or fall flows (when 

streamflow is commonly composed largely of ground-water 

discharge) from year to year can provide useful information on 

temporal variations in ground-water discharge.

Ground-Water Discharge to Streams by 

Subbasin

Sprague River Subbasin—Geographic Distribution of 

Ground-Water Discharge

The Sprague River subbasin encompasses the entire 

drainage above its confluence with the Williamson River, 

including the Sycan River drainage basin (fig. 7). The 

subbasin includes many runoff-dominated streams in the 

volcanic upper watersheds as wells as isolated springs and 

ground-water-dominated streams in the sediment filled valleys 

in the lower reaches of tributaries and along the main stem. 

Ground-Water Hydrology 23
OR19-0048_fig07

42°00'

41°30'

43°15'

43°00'

122°00' 121°00'

120°

45'

45'

45'

15'

45'

30'

30'

15' 122°30' 15'

5 0 5 10 15 20 MILES

Scale 1:1,000,000

5 0 5 10 15 20 KILOMETERS

OREGON

CALIFORNIA

Upper

Klamath

Basin

Butte

Creek

Whitney

Creek

Shasta River

Jenny

Cr

Fall

Cr

Edge Cr

Little Shasta River

Camp Cr

Scotch Cr

Dry Cr

Spencer

Whisky

Creek

Trout Cr

River

Williamson

Sun

Creek

Brown

Creek

 Creek

Mill Cr

Willow

Cr

Lost

River

Klamath

Strait

Klamath

River

Crater

Lake

Upper

Klamath

Lake

Summer Lake

Agency

Lake

Lake

of the

Woods

Lake Ewauna

John C. Boyle Reservoir

Copco

Lake

Iron

Gate

Res Tule

Lake

Lower Sump

Klamath

Lake

Clear

Lake

Res

Gerber

Reservoir

31

138

138

230

140

140

139

299

62

62

70

66

66

97

97

5

Silver

Lake

Road

Chemult Diamond 

Lake

Silver

Lake

Summer

Lake Lenz

Kirk

Chiloquin

Klamath

Agency

Fort

Klamath

Crater Lake

Prospect

Butte

Falls Rocky

Point Modoc

Point

Klamath Falls

Pinehurst Keno

Dorris Tulelake Langell

Valley

Malin

Merrill

Olene

Dairy

Bonanza

Lorella

Sprague

River

Beatty

Bly

Study area

boundary

K L A M AT H

D O U G L A S

L A K E

M O D O C

S I S K I Y O U

J A C K S O N

Shovel Cr

Jenny

Cr

Fall

Cr

River

Lost

Spencer

Larkin

Creek

Sycan

River

Spring

Creek

Wood

River

River

Long

Creek Williamson

Annie

Scott

Creek Sand

Creek

Springs

Big

Creek

Sheep

Creek

Creek

Brown

Creek

 Creek

Willow

Pit River

Miller Cr

Cr

River

River

River

Fork

Sprague

S Fork

N

Creek

Creek

Meryl

Fivemile

Cr

Creek

Jack

Sevenmile

Fourmile

Creek

Sprague

Sprague

Deming

Creek

Keno

Dam Lost River 

Diversion

Channel

Winter Ridge

Coleman Rim

Barns Rim

Mt

McLoughlin

Mount

Thielsen

Modoc Plateau

Sheepy Ridge

Bryant Mountain

Bly Ridge

Sycan

Marsh

Taylor

Butte Solomon

Butte

Pelican

Butte

Yainax

Butte

Gearhart

Mountain

Spodue

Mountain

Bly

Mt

Chiloquin

Narrows

Rocky

Ford

Wildhorse

Ridge

Torrent

Spring

Kamkaun

Spring

Whitehorse Spring

McReady

Spring

Medicine

Lake

Volcano

Klamath Hills

Klamath Valley

Yonna Valley

Swan Lake Valley

Yamsay

Mountain Klamath

Marsh

Brownsworth

Creek

Knot TablelandBrown

Spring

Mares Egg Spring

Wickiup

Spring

Miller

Creek

Sink

Creek

Cherry

Creek

Crane

Creek

Fourmile

Cr

The

Gap

Poe Valley

Stukel

Mountain

Fritz

Creek

Jackson

Creek

Willow

Creek

Cottonwood Creek

Sheepy

Creek Hot Creek

OREGON

CALIFORNIA

 EXPLANATION

Average annual rate of ground-water discharge to 

shaded stream reaches— In cubic feet per second 

per mile. See table 6 for reach number name.

 0.05-2.5

 2.5-5.0

 5.0-10.0

 10.0-25.0

 25.0-75.0

 75.0-200.0

End point between adjacent reaches 

with the same shade color

USGS streamflow gaging station with number

11510700

85

See table of contents for mapping sources

79

80 78

77

84

83

85

81

82

64

63

67

69

76

71 75

74

72

1

2

3

5 6

25

8 7

10

11

14

31

15

16

28

32-35

24

37 39

38

42

43

45 44

54 53

59

62

52

55 56

58

51 47

21

20

41

50

40

(50 ft/s 

net inflow)

65

(345 ft3/s 

net inflow)

68

(10 ft3/s 

net inflow)

66

(40 ft3/s 

net inflow)

73

70

11495500

11496500

11497000

11499100

11497500

11516530 11512000

11509500

11510000

11510700

11505600

11491400

11503000

11493500

11494000

11501000

11502500

11504000

11504100

Figure 7. Principal areas of ground-water discharge to streams and major springs in the upper Klamath Basin, Oregon and California, 

and selected stream-gaging stations. Shading along main stem reaches represents ground-water discharge (in cubic feet per second per 

mile) averaged along the entire shaded reach. The actual location of ground-water discharge may be localized. Shading along headwater 

streams represents the ground-water discharge averaged over the shaded reach and includes ground-water discharge to tributaries. See 

table 6 for detailed descriptions of measurement locations.

24 Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California
OR19-0048_fig08

Values estimatedfrom other sites

0

20

40

60

80

100

120

1932 1940 1950 1960 1970 1980 1990 2000 2005

WATER YEAR

TOTAL WATER-YEAR PRECIPITATION, IN INCHES

-40

-20

0

20

40

60

80

100

120

CUMULATIVE DEPARTURE FROM AVERAGE, IN INCHES

Total water-year precipitation at Crater Lake

Cumulative departure from average precipitation (1932-2005)

Average annual

precipitation

66.7 inches

Figure 8. Annual precipitation at Crater Lake National Park, Oregon, and the cumulative departure from average 

precipitation from 1932 to 2005. (Data from Western Regional Climate Center, 2006.)

The Sprague River responds relatively quickly to precipitation 

and snowmelt events, with peaks commonly exceeding 

2,500 ft3/s in April or May at the gaging station near Chiloquin 

(station 11501000). Mean monthly discharge at this location 

averages 1,300 ft3/s during April and 300 ft3/s during October. 

Major hydrologic features of the subbasin include the North 

and South Forks of the Sprague River, the Sycan River and 

Marsh, and Kamkaun Springs.

The Sprague River originates along the flanks of 

Gearheart Mountain and Coleman Rim in the highlands along 

the central-eastern edge of the upper Klamath Basin. From 

these highlands, the North and South Forks gain water from 

numerous tributaries as they flow down mountain canyons 

to the upper Sprague River Valley, above Beatty Gap. The 

hydrologic regimes of the North and South Forks have a 

pronounced runoff component and similar hydrographs near 

the uplands, with peaks occurring during snowmelt in the 

spring. However, above the Sprague River Valley, the North 

Fork gains significant ground water, whereas the South Fork 

does not.

From the confluence of the North and South Forks, the 

Sprague River meanders downstream through the narrowing 

upper Sprague River Valley, until it passes through Beatty 

Gap into the lower valley. Gains due to ground-water inflow 

occur in the upper valley, which contains both drained and 

un-drained wetlands. More ground-water discharge occurs to 

a spring complex (locally known as Medicine Springs) just 

downstream of Beatty Gap. From here, the Sprague River 

meanders through the lower Sprague River Valley for 75 mi, to 

its confluence with the Williamson River.

Aside from the runoff-driven Sycan River, tributaries 

north of the river and downstream of Beatty Gap are limited to 

a few unnamed ephemeral creeks draining the Knot Tableland 

and a few small springs near the mouth of the Sycan River. 

South of the river are four perennial and several ephemeral 

creeks. Three of the perennial creeks (Spring, Brown, and 

Whisky Creeks) are largely ground-water fed and lack a 

significant runoff component (fig. 7). (Note: The Spring Creek 

that is tributary to the Sprague River is too small to show at the 

scale of figures in this report. It enters the Sprague River just 

east of Brown Creek. The other Spring Creek mentioned in 

this report is tributary to the Williamson River.) An additional, 

but smaller amount of ground water discharges to Trout Creek 

as well as a few small springs near the mouth of Whisky 

Creek. Two large, isolated spring complexes, KamkaunMcReady and Whitehorse, farther downstream, are the only 

other ground-water discharge areas in the lower valley.

Ground-water discharge to the North and South Forks 

of the Sprague River (above the valley) was estimated using 

data from gaging stations with short periods of record and 

miscellaneous measurements made from 1992 to 2002. 

The spatial distribution of gains is relatively well known 

in the reaches and main tributaries of the North and South 

Forks (fig 7). However, the locations of specific springs 

have not been identified in either subbasin. Continuous and 

miscellaneous streamflow measurements were analyzed using 

index regression techniques on the North and South Forks to 

improve understanding of the temporal variability of groundwater discharge. Gains to the South Fork above the valley are 

Ground-Water Hydrology 25
about 24 ft3

/s, with most ground-water discharge occurring 

above the confluence with Brownsworth Creek (table 6). On 

the basis of regional regression, Deming and Fritz Creeks are 

estimated to contribute an additional 5 ft3/s of ground-water 

discharge to the system. Ground-water discharge to the North 

Fork is about 92 ft3/s, with one-third of the flow originating 

from Fivemile and Meryl Creeks. There are no direct inputs to 

the lower 10 mi of the North Fork.

The spatial distribution of ground-water discharge in 

the Upper Sprague River Valley (from the confluence of the 

North and South Forks to Beatty Gap) is more uncertain. 

Although there are no identified springs in the area, synoptic 

measurements show about 52 ft3/s of ground-water discharge 

along the 20-mi reach, including the main stem between 

Beatty Gap and the confluence of the North and South Forks, 

and the lower 11 mi of the South Fork (table 6).

The Lower Sprague Valley is defined as the area between 

the mouth of the river and Beatty Gap. The locations of gains 

in this valley are well known from numerous sets of synoptic 

measurements. Gains total about 150 ft3

/s. Ground water 

discharges directly to the river from the springs below Beatty 

Gap, Kamkaun, McReady, and White Horse Springs, as well 

as through tributaries at Whisky, Spring, and Brown Creeks. 

Even though ground-water discharge occurs at discrete 

locations, the locations can be lumped into two areas in the 

lower valley: (1) the valley between Whisky Creek and Beatty 

Gap (75 ft3/s), and (2) the valley near Kamkaun, Whitehorse, 

and McReady Springs (73 ft3/s) (fig. 7 and table 6). The 

temporal and spatial distribution of ground-water discharge in 

this subbasin is well understood given the multiple synoptic 

measurements made when the streamflow recorded at 

Chiloquin (11501000) was near the long-term average flow.

The Sycan River is the other main tributary to the 

Sprague River, but it contributes relatively little baseflow 

(historically about 30 ft3/s) given its drainage area of 563 mi2. 

The Sycan River is a snowmelt-runoff dominated stream, with 

peak flows occurring during the spring freshet (March–June). 

Monthly mean flows at the gaging station near Beatty indicate 

spring runoff flows are significant (400 ft3/s), whereas fall 

baseflows are minimal. Most tributaries to the Sycan River 

are ephemeral, contributing flow only during snowmelt 

or precipitation events, with ground water being a minor 

contributor to streamflow.

The Sycan River originates in the forested uplands east 

of Sycan Marsh on the western side of Winter Ridge, and is 

the only perennial tributary to Sycan Marsh from the east. 

At this location, the river has the characteristics of a runoffdominated stream, with peak flows occurring during spring to 

early summer and comparatively small baseflows in the fall. 

Long Creek is the main tributary west of Sycan Marsh and 

has lower peak flows, but a larger component of ground-water 

discharge than the Sycan River above the marsh, even though 

the watershed has about one-half the area. Ground-water 

discharge to the Sycan River and Long Creek above Sycan 

Marsh totals about 24 ft3

/s.

Preliminary hydrologic analysis of Sycan Marsh indicates 

that it is predominantly a surface-water dominated wetland. 

However, some ground water discharges to the marsh from 

numerous springs associated with a fen at the northern part of 

the marsh. Other than the Sycan River and Long Creek, most 

tributaries to the marsh are ephemeral, contributing flow only 

during snowmelt or precipitation events. Nested piezometers 

show a downward head gradient in most of the marsh, 

indicating that water moves from the surface downward (Leslie 

Bach, The Nature Conservancy, oral commun., 2005), which 

suggests that the marsh is an area of ground-water recharge.

The relation between the ground-water system and Sycan 

Marsh was evaluated by means of a water balance. Surface 

inflows and outflows from gaging station data were adjusted 

to the base period and then combined with precipitation and 

marsh evapotranspiration estimates to derive the ground-water 

gains or losses. The water balance resulted in a slight loss (-10 

to -20 ft3

/s), suggesting that the marsh may be a ground-water 

recharge area. This is consistent with the downward head 

gradient seen in piezometer nests. This water balance has a 

large uncertainty because of the evapotranspiration and soil 

moisture terms.

The lower Sycan subbasin (area between the mouth and 

Sycan Marsh) has relatively little ground-water discharge 

(21 ft3/s), which occurs at two locations. The first is an isolated 

spring, Torrent Spring (12 ft3/s), 10 mi downstream of Sycan 

Marsh. The second is from a number of springs, seeps, and 

creeks along the lower 10 mi of the river (fig. 7 and table 6).

Sprague River Subbasin—Temporal Variations in 

Ground-Water Discharge

Quantifying the temporal variations in ground-water 

discharge in the Sprague River subbasin is difficult due to a 

lack of data. Ground water discharges to a variety of spring 

complexes and spring-fed streams in the basin. Present gaging 

stations in the Sprague River subbasin are not well suited 

to provide direct measurement of ground-water discharge 

variations because of the effects of diversion. However, 

some inferences can be made by evaluating late-season 

flows at gages on the main stem with long periods of record. 

Gaging stations at Beatty and near Chiloquin provide useful 

information. However, diversions, tributaries, and probable 

irrigation return flow affect measurements at these locations. 

At Beatty, September mean discharge, the best proxy available 

for baseflow above that location, varied from about 80 ft3

/s to 

about 180 ft3/s during the period of record from 1954 to 1991. 

September mean discharge near Chiloquin (fig. 9) ranged from 

less than 150 ft3/s to greater than 350 ft3/s. Like other streams, 

the variations in September mean stream discharge generally 

follow climate cycles, with the highest flows following multiple 

wet years and the lowest flows following multiple dry years.

26 Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California
Williamson River Subbasin—Geographic Distribution of 

Ground-Water Discharge

The Williamson River originates from springs just east 

and south of Taylor Butte. From its source, the river flows 

almost due north through a wide, sediment-filled valley for 35 

mi before flowing west for 5 mi, where it historically spread 

over a delta into Klamath Marsh. The natural channel at the 

entrance to the marsh no longer exists, however, because the 

river has been diked and redirected. Most tributaries to the 

upper Williamson River originate along the flanks of Yamsay 

Mountain and the ridge to the south and are ephemeral, with 

flows occurring during spring snowmelt. However, significant 

springs contribute water directly to the upper Williamson 

River, which, as a result, has robust baseflow in addition to a 

runoff signal in its hydrograph during spring (fig. 10). Data 

recorded below Sheep Creek (station 11491400) indicates that 

flows average about 90 ft3

/s during spring and 57 ft3/s in fall 

(table 6).

The spatial distribution of ground-water discharge to 

the Upper Williamson River has been largely identified 

from synoptic measurements (fig. 7 and table 6). Ground 

water discharges directly into the Upper Williamson River 

at several large springs upstream from the gage below Sheep 

Creek (station 11491400) and averages 54 ft3

/s, with Wickiup 

Spring (24 ft3/s) being the largest single contributor (table 6). 

An additional 26 ft3/s of gain occurs between Sheep Creek 

and the marsh. Total ground-water discharge in the area is 

about 80 ft3

/s. The knowledge of the temporal variations in 

ground-water discharge to the Upper Williamson River is good 

upstream from the Sheep Creek gaging station owing to data 

from the long-term records at that site. However, between 

Sheep Creek and Klamath Marsh, no continuous streamflow 

record exists.

The only other perennial tributary that reaches Klamath 

Marsh is the spring-fed Big Springs Creek. However, even this 

creek may go dry during successive drought years (Newcomb 

and Hart, 1958). Surprisingly, Big Springs Creek shows a 

relatively flashy response to snowmelt and rainfall events 

that is atypical for spring-fed streams. Presumably, this rapid 

response is due to the ability of local rainfall and snowmelt to 

move easily through the very permeable pumice soils. Water 

in most other perennial streams draining to the marsh from the 

eastern side of the Cascades infiltrates into the pumice plain 

before reaching the marsh. Water in Sand and Scott Creeks 

would reach the marsh, but it is diverted to irrigate pasture 

lands on the western edge of the marsh.

Ground-water discharge to Big Springs, Sand, and Scott 

Creeks, and other tributaries west of Klamath Marsh, totals 

about 78 ft3

/s. About 12 ft3/s of the total discharge is to Miller 

and Sink Creeks, which lose their flow through infiltration into 

the pumice plain before reaching the marsh. Discharge to these 

streams was estimated from miscellaneous measurements 

and short-term gaging station data using index regression. 

All other tributaries are either ephemeral, or infiltrate into the 

pumice plain. OR19-0048_fig09

0

50

100

150

200

250

300

350

400

450

500

1920 1930 1940 1950 1960 1970 1980 1990 2000

DISCHARGE, IN CUBIC FEET PER SECOND

-50

-25

0

25

50

75

150

125

100

CUMULATIVE DEPARTURE FROM AVERAGE PRECIPITATION, IN INCHES 

September mean discharge - Sprague River near Chiloquin

Cumulative departure from average precipitation at Crater Lake (1932-2005)

Figure 9. September mean discharge of the Sprague River near Chiloquin, Oregon (USGS gaging station number 

11501000), and the cumulative departure from average precipitation at Crater Lake, Oregon.

Ground-Water Hydrology 27
A mass balance indicates that average net annual groundwater discharge directly to Klamath Marsh was approximately 

50 ft3/s between 1971 and 2000. This estimate is based 

on available gage data for tributary inputs, estimates for 

evapotranspiration, and direct precipitation on the marsh. The 

analysis assumes that the net change in water stored in the 

marsh during the 30-year period was negligible. The spatial 

distribution of ground-water discharge directly to the marsh is 

unknown.

The hydrograph of the Williamson River at the outlet of 

Klamath Marsh near Kirk (station 11493500, not shown) has 

a runoff signal, presumably from ephemeral tributaries and 

direct local runoff from the marsh. Flow of the Williamson 

River at the outlet of the marsh ceases during most summers 

due to the large amount of evapotranspiration in the marsh.

South of the gaging station near Kirk (altitude 4,483 ft), 

the Williamson River descends into a narrow, steep canyon 

as it drops in elevation. Small seeps and springs appear in 

the canyon walls near an altitude of 4,220 ft. As the river 

exits the canyon, three spring-fed streams contribute most of 

the baseflow to the Williamson River: Spring Creek, Larkin 

Creek, and Larkin Springs. Hydrographs of the Williamson 

River below these streams and above the Sprague River show 

a system with a large component of ground-water discharge 

that responds relatively slowly to precipitation and snowmelt 

events and that has gradual accession and recession curves. 

Peak flows commonly exceed 1,000 ft3

/s and usually occur in 

March. Low flows consistently range near 300 to 350 ft3/s and 

occur during summer. Gains to the river due to ground-water 

discharge below Klamath Marsh occur at Spring Creek (300 

ft3/s), Larkin Creek (10 ft3/s), Larkin Springs (10 ft3/s), and 

miscellaneous small springs (28 ft3/s) above Larkin Spring 

(table 6).

Williamson River Subbasin—Temporal Variations in 

Ground-Water Discharge

About 78 percent of the 67 ft3/s mean annual discharge 

of the uppermost Williamson River is composed of ground 

water. Information on fluctuations in ground-water discharge 

to the upper Williamson River comes largely from the gage 

downstream from Sheep Creek (station 11491400) operated 

since 1974. August–September flow of the upper Williamson 

River, which is mostly spring discharge, averages 52 ft3

/s. 

Synoptic measurements in November 2002 showed 54 ft3/s 

ground-water discharge to the reach (table 6). A graph of 

monthly mean flows of the Williamson River below Sheep 

Creek (fig. 10) shows that the base flow, as represented by 

September mean discharge, varies by a factor of nearly 2, 

from 37 to 70 ft3

/s. Comparing September mean flows with 

precipitation at Crater Lake (fig. 10) shows that this variation 

correlates with climate cycles. A plot of September flow of 

the Williamson River at Lenz and the cumulative departure 

from average precipitation at Crater Lake shows a positive 

linear relation with a correlation coefficient of 0.79 (fig. 11). OR19-0048_fig10

Monthly mean discharge

September mean discharge

Cumulative departure from average precipitation at Crater Lake (1932-2005)

0

20

40

60

80

100

120

140

160

180

200

1970 1975 1980 1985 1990 1995 2000

DISCHARGE, IN CUBIC FEET PER SECOND

0

50

100

150

200

250

300

350

400

CUMULATIVE DEPARTURE FROM AVERAGE PRECIPITATION

AT CRATER LAKE, IN INCHES 

Figure 10. Monthly mean discharge and September mean discharge of the Williamson River below Sheep Creek near 

Lenz, Oregon (USGS gaging station number 11491400), and the cumulative departure from average precipitation at 

Crater Lake, Oregon.

28 Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California
Part of the observed variation in September mean flow could 

be due to variations in surface-water diversions, which also 

are correlated with climate, as irrigation demands are less 

during wet periods and greater during dry periods. Given the 

small irrigated area above the gage (about 3,000 acres), the 

probable climate-driven variation in September diversions is 

small compared to the observed variations in streamflow. This 

indicates that most of the observed variation in September 

mean flow can be attributed to fluctuations in ground-water 

discharge.

Newcomb and Hart (1958) showed that ground-water 

discharge to Big Springs Creek varies from zero to about 90 

ft3/s in response to drought cycles. Meinzer (1927) shows the 

discharge of Big Springs Creek decreasing from 61 to 11.6 

ft3/s between 1914 and 1925 in a more or less linear manner in 

response to a general drying climate trend. La Marche (2002) 

noted that Big Springs Creek also shows seasonal fluctuations 

in response to annual snow melt. This suggests that Big 

Springs Creek is fed by a local, possibly perched, flow system.

The area of the lower Williamson River, between the gage 

at Kirk and the confluence with the Sprague River, is one of 

the major ground-water discharge areas in the upper Klamath 

Basin. About 86 percent of the ground-water discharge in this 

area is to Spring Creek, a short tributary to the Williamson 

River that is fed entirely by springs. The remaining groundwater discharge is to Larkin Creek, Larkin Springs, and other 

nearby springs.

Spring Creek is particularly important because it provides 

much of the flow to the Williamson River, an important source 

of water to Upper Klamath Lake, during summer. Many 

measurements of instantaneous streamflow have been made 

along Spring Creek during the past 100 years by the USGS 

and OWRD. Spring Creek flow varies with time and correlates 

with climate (fig. 12). The correlation coefficient between 

Spring Creek flow and the cumulative departure from average 

precipitation at Crater Lake between 1932 and 2002 is 0.72. 

Spring Creek is unaffected by surface-water diversions, and 

ground-water pumpage in the area is not enough to cause the 

observed discharge variations.

A more continuous measure of the ground-water 

discharge variations in the area can be developed using data 

from streamflow gages on the Williamson River near Kirk 

(11493500), the Sprague River near Chiloquin (11501000), 

and the Williamson River below the Sprague River, near 

Chiloquin (11502500). If the streamflow at the former two 

gages is subtracted from the latter, the positive residual 

(indicating a gain in streamflow between the gages) is due 

primarily to ground-water discharge, most of which is from 

Spring Creek. The ground-water discharge in this area, on the 

basis of September mean flows, averages about 306 ft3

/s, and 

ranges from about 250 to 400 ft3/s. The uncertainty of this 

estimate (on the basis of estimated gage error) is only about 

±30 ft3/s. This analysis is complicated by the fact that there are 

ungaged diversions from the Sprague River below the gage at 

Chiloquin, most notably the Modoc Irrigation District canal. 

Diversion records for the Modoc Canal are available from 

1915 to 1924, as are miscellaneous discharge measurements 

throughout the 1980s. Measurements of September flow 

average about 25 ft3/s. Accounting for this ungaged diversion 

increases the average ground-water discharge in this area 

based on gage data to 331 ft3/s. This figure compares 

favorably with the 350 ft3/s estimate based on synoptic and 

miscellaneous flow measurements. The temporal variations 

generally correspond to decadal precipitation cycles (fig. 12), 

and comparing the calculated September mean groundwater discharge and the cumulative departure from average 

precipitation at Crater Lake results in a correlation coefficient 

of about 0.68.

Upper Klamath Lake Subbasin—Geographic Distribution 

of Ground-Water Discharge

The Upper Klamath Lake subbasin encompasses 723 

mi2 above the outlet of Upper Klamath Lake, excluding the 

Williamson and Sprague drainages. The subbasin includes 

Upper Klamath Lake, the broad, flat Wood River valley to 

the north and the adjacent uplands including the Cascade 

Range to the west, Mt. Mazama (the Crater Lake highlands) 

to the north, and multiple fault-block mountains and the 

Williamson River delta to the east. The uplands on the 

eastern side rise abruptly from the valley floor along northsouth trending faults. The Wood River Valley is filled with 

Quaternary sediment, much of which is fine-grained and has 

low permeability. Major hydrologic features include the Wood 

River, Upper Klamath and Agency Lakes, and Sevenmile 

Creek.

OR19-0048_fig11

r = 0.79

30

35

40

45

50

55

60

65

70

75

-20 -10 0 10 20 30 40 50 60 70

CUMULATIVE DEPARTURE FROM AVERAGE PRECIPITATION

AT CRATER LAKE, IN INCHES

SEPTEMBER MEAN DISCHARGE, 

IN CUBIC FEET PER SECOND

Figure 11. Relation between the September mean 

discharge of the Williamson River below Sheep 

Creek near Lenz, Oregon (USGS gaging station 

number 11491400), and the cumulative departure 

from average precipitation at Crater Lake, Oregon.

Ground-Water Hydrology 29
The general hydrology of the subbasin is dominated by 

ground-water discharge from spring complexes coincident 

with fault scarps at the western and eastern edges of the Wood 

River Valley and Upper Klamath Lake (fig. 7). About one-half 

of the ground-water discharge in the subbasin occurs to the 

Wood River and its tributaries (table 6). Approximately onethird of the discharge occurs directly into Upper Klamath Lake 

at known and unknown locations. The remaining ground-water 

discharge occurs in the tributaries draining the eastern flank of 

the Cascade Range.

The Wood River receives the largest amount of ground 

water in the Upper Klamath Lake subbasin (490 ft3/s), with 

most of the discharge occurring at discrete spring complexes 

along the fault scarp on the eastern boundary of the valley 

(table 6). Two tributaries originating on the flanks of the 

Crater Lake highland, Annie and Sun Creeks, contribute 

roughly 14 percent of ground water discharged into the river. 

The estimates were derived from miscellaneous measurements 

taken in the Wood River subbasin, with subsequent regressions 

to index gages.

Ground water discharges from the Cascade Range to 

tributaries along the western margin of the subbasin at a rate of 

about 120 ft3

/s (table 6). The majority of that flow originates 

from tributary springs in the valley along the western fault 

scarp of the region. The creek with the largest watershed 

in this subarea, Fourmile Creek south of Pelican Butte, 

contributes only 2 ft3/s of baseflow to the region. Estimates 

were derived from short-term gaging station records and 

regression to index stations elsewhere in the basin.

Ground-water inflow to Upper Klamath Lake was 

estimated using a monthly water balance for the 1965 through 

1967 water years. Hubbard (1970) measured or calculated 

all tributary inflows and outflows from the lake, including 

streamflow, diversions, precipitation, evapotranspiration, and 

agricultural return flows. Hubbard’s monthly estimates of 

ground-water inflow to the lake of averaged about 350 ft3

/s 

from 1965 to 1967 (the median value is about 330 ft3/s). This 

is about 15 percent of the 2,330 ft3/s average total inflow to 

the lake during that period. Hubbard’s estimated ground-water 

discharge to the lake compares favorably with estimates of 

the difference between Upper Klamath Lake inflows and 

outflows (such as, ground-water inflow) by others such as 

Cooper (2004) that cover a much longer base period (30 years 

compared to 3 years). Hubbard’s estimate of average groundwater inflow was revised downward to about 320 ft3

/s by the 

Bureau of Reclamation (2005) using updated stage-capacity 

curves for the lake. Although many springs have been mapped 

around the margins of Upper Klamath Lake, their combined 

discharge is much less than the estimated ground-water inflow. 

Consequently, the spatial distribution of much of the groundOR19-0048_fig12 water inflow directly to the lake is unknown.

100

150

200

250

300

350

400

450

500

GROUND-WATER INFLOW, IN CUBIC FEET PER SECOND

-150

-100

-50

0

50

100

150

200

250

300

350

CUMULATIVE DEPARTURE FROM AVERAGE PRECIPITATION, IN INCHES

1910192019301940195019601970198019902000

Spring Creek discharge measurements

Cumulative departure from precipitation at Crater Lake 1913-2005—

 Dotted where estimated from Klamath Falls data.

Calculated September mean inflow between Kirk and Chiloquin

Figure 12. Discharge measurements of Spring Creek, estimated ground-water discharge to the lower Williamson 

River between Kirk and Chiloquin, and cumulative departure from average precipitation at Crater Lake, Oregon. (Spring 

Creek measurements from Hubbard and others, 1993, 1994; U.S. Geological Survey, various dates; and USGS and OWRD 

unpub. data; ground-water discharge estimated as the difference between the flow of the Williamson River below 

the Sprague River [gaging station 11502500] and the sum of flows of the Williamson River near Kirk [11493500] and the 

Sprague River near Chiloquin [11501000].)

30 Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California
Upper Klamath Lake Subbasin—Temporal Variations in 

Ground-Water Discharge

Temporal variations in ground-water discharge to Annie 

Spring can be evaluated using data from the gaging station 

(11503000) that has been operated on Annie Creek just below 

the spring since 1977 (fig. 13). The discharge from Annie 

Spring is small, averaging about 3 ft3/s. It is included here to 

illustrate the behavior of smaller flow systems. Annie Spring 

shows temporal variations that are different from those of the 

large-scale systems discussed previously. The lowest flows 

of large-scale spring systems are typically August through 

September. The lowest flows of Annie Creek, in contrast, are 

January through March. The likely cause is that Annie Spring 

is fed by ground water recently recharged and following very 

short flow paths, and consequently much of the water feeding 

the springs is frozen as snow during the winter months. The 

annual low flows of large-scale systems typically increase 

each year during periods of successive wetter-than-average 

years. This is less pronounced with Annie Creek. A graph of 

monthly and January to March mean flows of Annie Spring 

(fig. 13) shows that it peaks before the cumulative departure 

from average precipitation curve. This is because of the lack 

of storage effects in the small flow system. Annie Spring and 

similar small-scale flow systems in the upper Klamath Basin 

have the characteristics of runoff-dominated streams.

Gaging stations have been operated intermittently on 

the Wood River since 1913. However, data are not easily 

compared because the stations have been operated at different 

locations that are affected differently by tributary inflow, 

return flow, and diversion, and the periods of record are short, 

ranging from roughly 1 to 14 years. Although the gaging 

station data do not provide a continuous long-term record of 

ground-water discharge, they do provide useful information 

on the magnitude and timing of ground-water discharge 

fluctuations. A USGS gaging station at Fort Klamath 

(11504000) operated intermittently from 1913 to 1936 shows 

a probable drought-related decrease in annual mean flow from 

approximately 310 to 140 ft3

/s during its period of operation 

(fig. 14). Another USGS gaging station operated 4 mi south 

of Fort Klamath (11504100) from 1965 to 1967 shows a 

climate-related decrease in annual mean flow from 350 to 

290 ft3/s during that period. A gaging station was operated in 

the early 1990s, and recently near the headwaters springs of 

the Wood River (about 1 mile downstream at Dixon Road) 

by Graham Matthews and Associates (GMA). Variations 

in ground-water discharge to the Wood River headwater 

springs can be evaluated using the GMA data (provided by 

Graham Matthews, written commun., May 13, 2003) along 

with a multitude of miscellaneous instantaneous discharge 

measurements made over several decades by USGS and 

OWRD (fig. 14). The measurements near the headwaters 

0

2

4

6

8

10

12

14

16

1975 1980 1985 1990 1995 2000

DISCHARGE, IN CUBIC FEET PER SECOND

-100

-50

0

50

150

100

CUMULATIVE DEPARTURE FROM AVERAGE PRECIPITATION, IN INCHES 

Monthly mean discharge

January to March mean discharge

Cumulative departure from average precipitation at Crater Lake (1932-2005)

Figure 13. Monthly mean discharge and January to March mean discharge of Annie Spring near Crater Lake, 

Oregon (USGS gaging station number 11503000), and the cumulative departure from average precipitation at Crater 

Lake.

Ground-Water Hydrology 31
springs are largely unaffected by tributary inflow and 

diversions, and are not noticeably influenced by the presently 

small amount of ground-water pumping in the area. Variations 

in ground-water discharge to the Wood River headwater 

springs correlate well with the cumulative departure from 

average precipitation at Crater Lake (r = 0.75). Measurements 

show the discharge of Wood River near the headwaters springs 

increasing from 180 to 320 ft3/s during wet conditions in the 

early 1980s, and then decreasing from 320 to 160 ft3/s owing 

to drought in the late 1980s and early 1990s. This reduction in 

ground-water discharge to this single spring complex applied 

over 1 year equates to 114,000 acre-ft of water.

A synthetic hydrograph of the Wood River near the 

headwaters springs can be created by using the relation 

between Wood River discharge measurements and concurrent 

daily mean flows from the gaging station on Fall River 

(14057500), a similar-scale spring-fed stream about 70 mi 

north in the Deschutes Basin (fig. 14). The relation can be 

modeled using a second order polynomial with an R2

 of 0.80. 

This synthetic hydrograph provides a reasonable depiction 

of the continuous temporal variations in the discharge of the 

Wood River headwaters springs.

Temporal variations in ground-water discharge directly 

to Upper Klamath Lake have not been measured. Given the 

magnitude of the inflow (320 to 350 ft3/s), temporal variations 

can be inferred from other springs in the area with comparable 

discharge rates and flow-path lengths (such as Wood River 

Springs).

Lost River Subbasin—Geographic Distribution of 

Ground-Water Discharge

The Lost River subbasin occupies about 1,650 mi2

southeast of Upper Klamath Lake. In its natural state, the 

Lost River subbasin had no outlet and it drained internally. 

Water occasionally flowed to the subbasin, however, from the 

Klamath River during floods through a slough connecting the 

two drainages south of Klamath Falls (La Rue, 1922). With 

the development of Reclamation’s Klamath Project and the 

construction of the Lost River diversion dam and channel 

(fig. 3), controlled flow between the Klamath and Lost Rivers 

in both directions now occurs. Major hydrologic features in 

this subbasin include Clear Lake and Gerber Reservoirs in the 

uplands, the Lost River, and the Tule Lake Sump.

OR19-0048_fig14 DISCHARGE, IN CUBIC FEET PER SECOND

CUMULATIVE DEPARTURE FROM AVERAGE PRECIPITATION, IN INCHES 

19101915192019251930193519401945195019551960196519701975198019851990199520002005

0

50

100

150

200

250

300

350

400

450

-100

-50

0

50

100

150

200

250

300

Synthetic hydrograph of discharge at Dixon Road

Monthly mean flow at Dixon Road (GMA gage)

Instantaneous discharge measurements at Dixon Road

Monthly mean flow at Weed Road (USGS Gage 11504100)

Monthly mean flow at State Hwy 62 (USGS Gage 1504000)

Cumulative departure from precipitation at Crater Lake 1913-2005—

 Dotted where estimated from Klamath Falls data.

Figure 14. Discharge of the Wood River as measured or estimated at various sites, and the cumulative departure 

from average precipitation at Crater Lake, Oregon. (Monthly mean flow near headwaters from Graham Matthews, 

GMA, written commun. May 13, 2003; flow measurements near headwaters from USGS, various dates, and OWRD 

unpub. data; estimated discharge at Dixon road derived from regression with Fall River in upper Deschutes Basin 

[USGS gaging station 14057500], a similar size spring-fed stream.)

32 Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California
The Lost River proper originates at the outlet of Clear 

Lake Reservoir in the southeastern part of the basin. From 

there the river flows northwest, dropping from the plateau 

containing Clear Lake into the Langell Valley where the river 

flows to the town of Bonanza. From there it flows west into 

Poe Valley and subsequently through Olene Gap into the 

Klamath Valley before turning southeast and terminating in the 

Tule Lake Sump in California.

The hydrology of the Lost River subbasin is runoff 

dominated above Clear Lake and Gerber Reservoirs. The 

drainage area of Clear Lake consists of a broad, low relief, 

volcanic plateau with a mean altitude of roughly 5,000 ft 

covering more than 750 mi2 south and east of the lake. Only 

one perennial stream, Willow Creek, exists in the plateau. 

Values for monthly mean inflows to Clear Lake (calculated 

from a mass balance) show that high flows occur in March 

(500 ft3/s), whereas low flows occur in late summer (30 ft3/s). 

The lands draining to Gerber Reservoir are more mountainous 

than those draining to Clear Lake, but are geologically similar. 

Mean monthly inflows to Gerber Reservoir are highest in 

March (280 ft3

/s) and lowest during the late summer (4–5 

ft3/s). Water from Gerber Reservoir flows to the Lost River via 

Miller Creek.

Several springs contribute flow to the Lost River 

subbasin in the sediment filled Langell, Yonna, and Poe 

valleys. Bonanza Spring, near the town of Bonanza, is a major 

contributor of baseflow to the river as are a series of springs 

adjacent to the river near Olene Gap.

 Little historical data are available with which to estimate 

ground-water discharge in most of the Lost River subbasin. 

For Clear Lake and Gerber Reservoirs, USGS streamgaging 

data collected prior to the construction of the reservoirs were 

used along with inflows reported by Reclamation (Bureau of 

Reclamation, 1954, Appendix B) to estimate ground-water 

discharge during fall. The average discharge during the period 

of record was 40 ft3/s and 10 ft3/s, respectively for the two 

reservoirs. Limited data for the remaining area are available 

from gages operated intermittently in the early 1900s and 

late 1990s on the Lost River. Sets of synoptic measurements 

(Leonard and Harris, 1974; Grondin 2004) were sufficient 

to determine the location of gains to the river below the 

reservoirs. These measurements demonstrate that most 

ground-water discharge into the Lost River proper occurs at 

two locations: Bonanza Springs and the area just upstream of 

Olene Gap. The overall gain to the river between Olene and 

the two reservoirs is about 140 ft3

/s, largely on the basis of 

synoptic measurements. The temporal variability of groundwater inflow is poorly known owing to the short periods of 

record. Below Olene Gap, data were insufficient to estimate 

ground-water discharge to the river. Likewise, data were 

insufficient to estimate direct ground-water discharge to the 

Tule Lake Sump.

Lost River Subbasin—Temporal Variations in 

Ground-Water Discharge

Bonanza Springs is the only location in the Lost River 

subbasin where data are sufficient to evaluate temporal 

variations in ground-water discharge. These springs discharge 

from basalt to the Lost River. Twenty-one discharge 

measurements of the springs, made by USGS, OWRD, or 

Reclamation, are in the published and unpublished literature 

(fig 15). Discharge of the springs is in all cases determined 

by comparing the difference in streamflow of the Lost River 

upstream and downstream from the town of Bonanza. Many 

upstream measurements were made between 2 and 3 mi 

from Bonanza, and some were made at a bridge about 5 mi 

upstream. Downstream measurements all have been made 

about 3 mi downstream at Harpold Dam. Some determinations 

of spring flow account for all tributary inflows (including 

agricultural drains) and diversions between the upstream and 

downstream measurement sites. Other than Bonanza Springs, 

these gains and losses are minor outside of the irrigation 

season. Many determinations of spring flow include only the 

upstream and downstream measurements and measurement 

of the single major tributary, Buck Creek. Determinations 

of spring discharge made by comparing flows only at Keller 

Bridge, Buck Creek, and Harpold Dam outside of the 

irrigation season are considered reasonable because the spring 

discharge is much larger than the other stream gains and 

losses.

Discharge measurements of Bonanza Springs show 

considerable temporal variation (fig. 15). The largest 

measurement, 118 ft3

/s in October 1958, occurred after a 

15-year period of wetter-than-average weather. The smallest 

measurement, 38 ft3/s in January 1992, occurred late in a 

drought that started in the mid-1980s. Overall, the pattern of 

spring discharge follows the general pattern of precipitation, 

reflecting drought cycles and a general drying trend since 

the late 1950s. Unfortunately, no measurements are available 

from the very dry period in the early 1940s. Bonanza Springs 

discharge is affected by climate, ground-water pumping, and 

artificial manipulation of the stage of the Lost River (Grondin, 

2004). Discharge from the main spring can cease entirely 

during the irrigation season in dry years. Most measurements 

after 1960 (fig. 15) were made well after the irrigation season 

(December to April), so the system should have mostly 

recovered from the seasonal effects of pumping and diversion. 

Present information is insufficient, however, to determine 

precisely how much of the variation in spring discharge is 

natural and how much is related to pumping.

Ground-Water Hydrology 33
Klamath River Subbasin—Geographic Distribution of 

Ground-Water Discharge

The Klamath River subbasin encompasses the area 

between the outlet of Upper Klamath Lake and Iron Gate 

Dam. The main hydrologic features are John C. Boyle, Copco, 

and Iron Gate Reservoirs, Lake Ewauna, Lower Klamath Lake, 

and the Klamath River. The Klamath River begins at the outlet 

of Upper Klamath Lake, where, for the first mile or so, it is 

known as the Link River. From the dam, the Link River flows 

about 1 mi through a narrow gorge into a broad, flat valley 

containing Lake Ewauna, the head of Klamath River proper. 

Lake Ewauna, impounded by Keno Dam, is a long, narrow 

reservoir that traverses the northern part of the Lower Klamath 

Lake subbasin.

Prior to development of the region, the Klamath River 

occasionally spilled across the low, nearly level divide 

into the Lost River subbasin during floods. La Rue (1922) 

hypothesized that water also may have flowed from the Lost 

River to the Klamath River subbasin during floods. Recent 

analysis of topographic mapping from the early 1900s, 

however, suggests that the Lost River was incised to the 

degree that flow from the Lost River system to the Klamath 

River subbasin was highly unlikely (Jon Hicks, Bureau of 

Reclamation, oral commun., 2006). Water also moved between 

the Klamath River and Lower Klamath Lake subbasin prior 

to development. Water flowed from the Klamath River into 

Lower Klamath Lake during periods of high flow, usually in 

winter or spring. After high flows, water would flow out of the 

lake through the Klamath Strait back into the Klamath River. 

There is some uncertainty as to timing and duration of flow 

from the lake to the river, and it probably varied from year to 

year with hydrologic conditions (Weddell, 2000; Bureau of 

Reclamation, 2005). Flows into and out of the Lost River and 

Lower Klamath Lake subbasins are now controlled.

Downstream from Lake Ewauna and Keno Dam, the 

Klamath River enters a canyon and flows into John C. Boyle 

Reservoir (operated by PacifiCorp), near the confluence with 

Spencer Creek. Below John C. Boyle Dam, the river drops 

into another steep canyon. About 1 mile below the dam, 

a large spring complex contributes significant flow to the 

river. Numerous perennial streams originating from the High 

Cascades and older Western Cascades also add flow to the 

river between Keno and Iron Gate Dams. These tributaries 

are predominately runoff dominated; however several (for 

example, Spencer and Fall Creeks) have large components of 

ground-water discharge. Flows in the Klamath River above 

Iron Gate Dam are largely regulated by Reclamation and 

PacifiCorp impoundments, including Link River Dam at the 

outlet of Upper Klamath Lake. Gaging station data from below 

Iron Gate Dam (11516530) show a high mean monthly flow of 

3,600 ft3

/s in March and a low mean monthly flow of 770 ft3/s 

in August.

OR19-0048_fig15 DISCHARGE, IN CUBIC FEET PER SECOND

CUMULATIVE DEPARTURE FROM AVERAGE PRECIPITATION, IN INCHES 

19101915192019251930193519401945195019551960196519701975198019851990199520002005

0

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-25

0

25

50

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125

Published measurements with estimated 95% confidence intervals

Unverified measurements

Cumulative departure from precipitation at Crater Lake 1913-2005—

 Dotted where estimated from Klamath Falls data.

Figure 15. Discharge of Bonanza Springs and cumulative departure from average precipitation at Crater Lake, 

Oregon. (Sources of data: Meinzer, 1927; U.S. Geological Survey, 1956, 1960a; Leonard and Harris, 1974; Grondin, 

2004; measurements labeled unverified appear in official State of Oregon correspondence and are attributed to 

Reclamation and USGS, but no original records were found.)

34 Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California
Most ground-water discharge in this subbasin occurs 

along the Klamath River and principal tributaries. A small 

amount of ground water also discharges to springs southwest 

of Lower Klamath Lake. Ground-water discharge in the 

Klamath River subbasin was calculated directly from longterm streamflow data and corrected for reservoir storage in 

reaches of the Klamath River from the gaging station at Keno 

(11509500) to the gaging station below the John C. Boyle 

Power Plant (11510700) (about 5 mi below the dam), and 

from that gage to the gage below Iron Gate Dam (11516530). 

Some short-term streamflow records available for tributaries 

were useful for discriminating ground-water discharge directly 

to the river from discharge to tributaries. Gains and losses 

between Link River Dam and Keno were not estimated owing 

to large uncertainties in the data in that reach. Discharge to 

springs southwest of Lower Klamath Lake was not measured 

for this study, but measurements are available from Wood 

(1960) and Reclamation records.

The largest source of ground-water discharge between 

the gage at Keno and the gage below the John C. Boyle 

Power Plant is a series of springs about a mile below the 

dam (fig. 7 and table 6). Although early references to these 

springs are scarce, Newcomb and Hart (1958) note that springs 

contribute “considerable inflow” to the river in this area. 

Their observations and those of local residents cited in their 

report predate construction of John C. Boyle Dam, indicating 

that these springs do not merely represent reservoir seepage. 

Records show that average gain from the springs is about 

190 ft3/s (table 6). The temporal variation in the discharge of 

these springs is well characterized. The baseflow of Spencer 

Creek, tributary to the Klamath River in this reach, is about 

27 ft3/s.

Between the gage below the John C. Boyle Power Plant 

and that below Iron Gate Dam, gains averaged 140 ft3/s from 

1967 to 2000 (table 6). The spatial location of the groundwater discharge in this reach is not well known; however, there 

is evidence of inflow to the main stem of the Klamath River 

between river miles 207 and 213, roughly between Shovel 

and Rock Creeks. Thermal infrared remote sensing shows that 

the river cools in this reach, an indication of ground-water 

discharge (Watershed Sciences, 2002). This reach corresponds 

with the boundary between the High Cascade and Western 

Cascade subprovinces and is therefore an area of expected 

ground-water discharge. In addition, the reach traverses a 

large landslide complex with numerous mapped springs. Some 

inflow in this reach is due to tributary streams. Fall Creek, 

which drains an area dominated by rocks of the High Cascade 

subprovince, is the largest known contributor, with a baseflow 

of about 36 ft3

/s, whereas the much larger Jenny Creek 

watershed, which is underlain largely by low-permeability 

older volcanic rocks, contributes only about 9 ft3

/s. Flow data 

are sparse for the remaining tributaries in Oregon, but regional 

regression techniques show that these contributions probably 

amount to slightly greater than 1 ft3/s. The component of 

baseflow to the reach from California tributaries is unknown.

Ground water also discharges to a number of spring 

complexes southwest of Lower Klamath Lake (fig. 7

and table 6). Reclamation engineer Louis Hall made a 

reconnaissance of the Lower Klamath Lake subbasin in 

September 1908 during which he inventoried springs along 

the margin of the lake and estimated their discharge. His 

estimates of spring discharge to the lake total 104 ft3/s, 

although his estimating methods are not known (Tom Perry, 

Bureau of Reclamation, written commun., 2006). Wood 

(1960) made several measurements of discharge at three 

of the principal spring complexes during water year 1955. 

He also reports CDWR observations that year for a fourth 

discharge measurement. Wood’s measurements are not directly 

comparable to Hall’s earlier estimates because of differences 

in locations; however, in cases where general comparisons can 

be made, Wood’s measured flows appear to be about one-half 

of Hall’s estimates. Averages of Wood’s measurements total 

about 35 ft3

/s. Some small seasonal variability is evident in the 

measurements, but the data are too sparse to define a pattern 

and identify the source of the variability. Measurements made 

in 1955 may reasonably represent the average flow during the 

early 1950s. Precipitation during water year 1955 was less 

than average, but 1953 and 1954 were close to the long-term 

average. Discharge of these springs probably is now less than 

it was in the mid-1950s, owing to dryer conditions in recent 

decades and increased ground-water development in the area.

Klamath River Subbasin—Temporal Variations in GroundWater Discharge

The principal sources of data used to evaluate groundwater discharge variations in the Klamath River subbasin are 

stream-gaging stations at Keno (11509500), below the John 

C. Boyle power plant (11510700), and below Iron Gate Dam 

(11516530). These data are augmented with short-term gaging 

station records from Spencer and Fall Creeks (11510000 

and 11512000, respectively). Understanding ground-water 

discharge variations along the Klamath River, however, is 

complicated by inflow from ungaged tributaries, unmeasured 

diversions, and changes in reservoir storage.

Ground-water discharges to the Klamath River between 

the Keno gage and the gage below the John C. Boyle power 

plant. Nearly all of the discharge is from a spring complex 

near river mile 224 about 1 mi below the John C. Boyle Dam 

and about 3.5 mi above the power plant. Thermal infrared 

remote sensing on July 15, 2002, showed that this spring 

complex cooled the river about 10°F (Watershed Sciences, 

2002). Gage data indicate the flow in the river just below the 

springs was about 370 ft3

/s on that date. Temporal variations 

Ground-Water Hydrology 35
in net ground-water discharge to this reach can be evaluated 

by comparing August mean flows at the two gages and 

accounting for changes in storage of John C. Boyle Reservoir 

(reservoir data from Rob Allerman, PacifiCorp, written 

commun, 2002). August means were used to evaluate temporal 

variations here instead of the September–November means to 

minimize the effects of fall storms. This can be done because 

diversions are insignificant and the mean August inflow (240 

ft3/s) is reasonably close to the mean September–November 

inflow (230 ft3/s).

A graph showing the August mean net inflow to the 

reach between Keno and the gage below the John C. Boyle 

power plant (fig. 16) shows that ground-water discharge to this 

reach varied from less than 200 ft3/s to greater than 300 ft3/s 

during the period of record. The average error in the individual 

inflow estimates is approximately ± 50 ft3/s on the basis of 

measurement error of the stream gages. The general pattern 

of ground-water discharge loosely follows the decadal cycles 

seen in precipitation, with the lowest inflows corresponding to 

extended periods of drought, but that correlation is low 

(r = 0.30).

Ground-water discharge also occurs to the Klamath River 

between the gaging station below the John C. Boyle power 

plant and the gaging station below Iron Gate Dam. Evaluating 

temporal variations in ground-water discharge to this reach 

is made difficult by ungaged tributary inflow and probable 

diversions. Moreover, calculated inflow values include 

cumulative errors in data from the two gaging stations and 

in storage measurements of two large reservoirs. As with the 

upstream reach, temporal variations in ground-water discharge 

can be evaluated by calculating the differences between flows 

at the two gages and accounting for changes in reservoir 

storage (fig. 16). September to November mean inflows are 

used here to minimize the effects of diversions.

Between 1967 and 2002, the September to November 

mean inflow between the gaging stations below the John C. 

Boyle power plant and Iron Gate Dam ranged from 30 to 330 

ft3/s, averaging 140 ft3/s (fig. 17). About 45 ft3/s if this inflow 

is from Fall and Jenny Creeks (table 6). The uncertainty of the 

inflow estimates due to measurement error is ± 110 ft3

/s. The 

correlation between ground-water discharge and climate is not 

as apparent here as elsewhere in the basin owing to the small 

amount of net ground-water inflow relative to the streamflow 

measurement error.

INFLOW, IN CUBIC FEET PER SECOND

CUMULATIVE DEPARTURE FROM AVERAGE PRECIPITATION, IN INCHES 

1960 1965 1970 1975 1980 1985 1990 1995 2000 2005

-100

-50

0

50

100

150

200

0

50

100

150

200

250

300

350

400

Cumulative departure from average precipitation at Crater Lake (1932-2005)

PacifiCorp spring discharge estimates

August mean inflow between gages at Keno and below the J.C. Boyle Dam

Figure 16. August mean gains in flow (a proxy for ground-water discharge) between Keno (USGS gaging station number 

11509500) and the John C. Boyle power plant (11510700), estimates of inflow by PacifiCorp, and the cumulative departure 

from average precipitation at Crater Lake, Oregon. (PacifiCorp data from Rob Allerman, written commun., 2002).

36 Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California
Summary of Geographic and Temporal Variations 

of Ground-Water Discharge to Streams

Analysis of streamflow data indicates that many streams 

in the upper Klamath Basin have a large component of ground 

water. Most streams throughout the world rely on groundwater discharge to support flows during the dry season. The 

upper Klamath Basin and other basins on the eastern flank of 

the Cascade Range are unique in that ground water discharge 

composes a large proportion of the total streamflow. This is 

attributable to the substantial regional ground-water system 

that exists in the permeable volcanic terrane. Some major 

streams in the basin, such as the Wood River and Spring 

Creek, are virtually entirely ground water fed. It has long 

been recognized that much of the water flowing into Upper 

Klamath Lake originates as ground-water discharge (Bureau of 

Reclamation, 1954, p. 150). Of the 2,200–2,300 ft3/s average 

total inflow to the lake (from Hubbard, 1970, and Reclamation 

records), at least 60 percent can be attributed to ground-water 

discharge in the Wood River subbasin and springs in the lower 

Sprague River drainage and the Williamson River drainage 

below Kirk. This quantity does not include ground-water 

discharge to upper parts of the Williamson and Sprague River 

systems, which would make the figure even larger. The large 

component of ground water in streamflow influences the 

hydrologic response of the basin to climate cycles, and has 

implications for flow forecasting (Risley and others, 2005).

OR19-0048_fig17 INFLOW, IN CUBIC FEET PER SECOND

CUMULATIVE DEPARTURE FROM AVERAGE PRECIPITATION, IN INCHES 

1965 1970 1975 1980 1985 1990 1995 2000

-50

0

50

100

150

250

200

0

50

100

150

200

250

300

350

400

Cumulative departure from average precipitation at Crater Lake (1932-2005)

September-November mean inflow between J.C. Boyle Power Plant and Iron Gate Dam

Figure 17. September to November mean gains in flow (a proxy for ground-water discharge) between the John C. 

Boyle power plant (USGS station number 11510700) and Iron Gate Dam (11516530), and the cumulative departure from 

average precipitation at Crater Lake, Oregon.

Discharge from all major ground-water discharge areas 

in the basin fluctuates over time. Ground-water discharge 

fluctuations are primarily climate driven, and, therefore, 

discharge from the various sources tends to vary in unison. 

Owing to the effects of ground-water storage, regional-scale 

discharge areas integrate climate conditions over multiple 

years. Consequently, ground-water discharge fluctuations 

tend to follow a pattern similar to the cumulative departure 

from average precipitation. A practical implication of this 

observation is that ground-water discharge from storage may 

support robust streamflow during a dry year following a series 

of wet years. Conversely, it may take multiple years of average 

or above average conditions following a protracted drought to 

replace ground-water storage and return spring discharge (and 

hence, streamflow) to predrought conditions.

Ground-water discharge variations can represent 

substantial volumes of water on an annual basis. The 

combined ground-water discharge to the lower Williamson, 

Sprague, and Wood Rivers just upstream of Upper Klamath 

Lake can vary by at least 450 ft3

/s in response to climate 

cycles. This equates to an annual volume of 326,000 acreft. The actual variation in ground-water discharge to Upper 

Klamath Lake and its tributaries is larger, because the probable 

variations in ground-water discharge to Fort Creek, Crooked 

Creek, and springs discharging directly to the lake have not 

been included. Gaging station data show that net ground-water 

inflow to the Klamath River (and ground-water fed tributaries) 

between Keno and Iron Gate Dam probably varies at least 150 

ft3

/s in response to climate.

Ground-Water Hydrology 37
Ground-Water Discharge to Wells

Ground water pumped from wells in the upper Klamath 

Basin is used primarily for public supply and agriculture. 

For public supply, ground water is provided by public or 

privately owned utilities for drinking, municipal, industrial, 

and commercial purposes. Most ground water pumped for 

irrigation is used for agriculture; however, some is used for 

irrigation of cemeteries, parks, and golf courses. The following 

discussion is limited to ground-water withdrawals for publicsupply and agricultural irrigation. Industrial and domestic 

withdrawals from individual private wells are not discussed 

because their proportion of the total ground-water use in the 

basin is small.

Methods

Ground-water pumping for public-supply and irrigation 

was estimated using different methods. Since 1985, OWRD 

has required public suppliers to report ground-water pumpage 

annually. Public suppliers in Oregon report monthly pumpage 

totals by individual well for each water year. The totals 

typically are based on direct flowmeter measurements or 

calculated from pumping rates and duration of pumping. The 

totals for this report were based on reported pumpage in 2000. 

No pumpage data were available for the small California 

communities of Dorris, Macdoel, and Tulelake. Groundwater withdrawals for these suppliers were estimated using 

population data.

Neither Oregon nor California requires well owners 

to report ground-water withdrawals for irrigation. Some 

irrigators in Oregon report their yearly pumpage to OWRD 

either voluntarily or as required by conditions in their waterright permit, but such reporting is rare. The lack of any 

comprehensive reporting system by both States means that 

indirect methods based on water right information, satellite 

imagery, and land and water surveys must be used to estimate 

the rate and distribution of ground-water withdrawal.

Ground-Water Pumpage for Public-Supply Use

Ground water is the source of water supplied by eight 

public systems and one quasi-public system in the study area. 

Public suppliers of ground water include the communities of 

Klamath Falls, Bly, Chiloquin, Merrill, and Malin. One resort 

community northwest of Klamath Falls is considered a quasimunicipal system on the basis of the variety of water uses. 

Ground-water withdrawals for the communities of Dorris, 

Macdoel, and Tulelake were estimated using recent population 

totals and a per capita use of 150 gallons per day (according 

to the methods of Broad and Collins, 1996). Public-supply 

systems that served more than 25 people or had at least 15 

connections pumped approximately 9.3 Mgal/d (million 

gallons per day) or about 14.4 ft3

/s in 2000. By comparison, 

in the 5-year period from 1996 through 2000, public supply 

withdrawals in the basin averaged an estimated 8.2 Mgal/d 

(12.7 ft3

/s). The City of Klamath Falls, with a population of 

19,400, accounted for 84 percent of the 2000 total, reporting 

withdrawals of 7.8 Mgal/d (12.1 ft3/s) from 9 city wells. Per 

capita use in cities such as Klamath Falls is larger than in rural 

areas and small towns due to the larger relative amount of 

commercial, industrial, and irrigation included.

Ground-Water Pumping for Irrigation

In Oregon, ground-water pumpage for irrigation was 

estimated by matching maps of primary and supplemental 

irrigation ground-water rights to areas that were determined 

to be irrigated by using a land-cover data set created from 

30-meter resolution Landsat satellite imagery taken during 

the 2000 irrigation season. The Landsat image data were 

analyzed to help identify vegetation types and conditions (such 

as the stage of growth) in a process known as “classification.” 

The ground-water rights data sets consisted of geographic 

information system (GIS) layers showing places of use 

(POUs) and points of appropriation (POAs), and were 

provided by the OWRD along with data from their Water 

Rights Information System. The POUs represent the fields 

where water is applied under the terms of the water right. That 

right might be a primary right for ground-water irrigation, 

or a supplemental right under which ground water is used 

to supplement a primary surface-water right on the same 

land. A water-right can cover a single tract or several tracts 

not necessarily adjacent to one another. POAs correspond to 

specific wells at particular locations on ground-water rights. 

A single ground-water right may include more than one 

well. Pumpage was estimated only for active primary and 

supplemental ground-water rights for irrigation outside of 

irrigation district boundaries. It was assumed that no primary 

ground-water rights are in areas included in irrigation districts 

within the Klamath Project, and that supplemental groundwater irrigation within irrigation districts was negligible in 

2000.

The POU boundaries were overlaid with the lands 

determined to be irrigated using the classified Landsat imagery 

(fig. 18). The purpose of the overlay was to match specific 

water rights to irrigated areas shown on the land-cover map 

developed from the imagery. The results reveal which fields 

with ground-water rights were actually irrigated during the 

2000 irrigation season. Partial overlay matches, where either 

the irrigated lands from the imagery did not completely fill a 

POU field boundary or the imagery showed many small blocks 

of irrigated areas within a field boundary, were evaluated 

individually and the acres included or dropped (considered 

irrigated or not irrigated) on the basis of specific criteria. 

Any irrigated fields smaller than 3 acres were eliminated. 

Ground-water pumpage used in irrigated areas was assigned 

to a specific well based on water right information. Where 

the land-cover data showed an obvious irrigated field (for 

38 Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California
example, from a center pivot) but no matching water right in 

the GIS data set, a withdrawal location based on the centroid 

of the field was used. In total, 19,250 acres of cropland in the 

upper Klamath Basin in Oregon was estimated to have been 

irrigated with ground water in 2000, or about 30 percent of 

the 64,000 acres with Oregon primary ground-water rights 

evaluated in this analysis.

The estimation method produced a conservative number 

of irrigated acres and points of appropriation. The apparent 

low percentage of ground-water rights exercised in 2000 

may be attributable to counting only the acres appearing to 

be irrigated on Landsat images rather than the total acreage 

carried on the water right, and editing criteria that were 

more likely to eliminate than include fields where evidence 

of irrigation was questionable on the satellite image. Any 

irrigation in areas not included in the OWRD digital water 

right POU maps is not included in the estimate. Estimates 

of pumpage within irrigation district boundaries under a 

pilot water bank and similar programs starting in 2001 are 

discussed in a separate section

The crop types in areas irrigated with ground water in 

Oregon were determined from the classified Landsat satellite 

imagery using the methodology described in appendix A. 

Specific crop types could not be reliably identified using the 

Landsat imagery. Five vegetative classes of crop types were 

identified, however, on the basis of spectral signatures and 

potential water requirements. The five classes are (1) alfalfa 

and irrigated grasses, (2) small grains, (3) onions and garlic, 

(4) potatoes and corn, and (5) strawberries.

About 40,000 acres were irrigated with ground water in 

the upper Klamath Basin in California during 2000. California 

water law does not require a permit or approval to withdraw 

ground water from wells (California State Water Resources 

Control Board, 1990). The estimation of ground-water 

withdrawals in this report relied primarily on data compiled 

from a comprehensive land and water survey by the CDWR’s 

Northern District in summer 2000 for the State water plan 

update (Todd Hillaire, CWDR, written commun., April, 28, 

2003). For each tract of land surveyed, CDWR determined 

the source of water, crop type and in most instances, the type 

of irrigation system used. The estimate in this report includes 

only those lands assessed through the survey as entirely or 

partially irrigated with ground water.

Irrigation water use on individual parcels was estimated 

based on the crop type, acreage, crop-water requirements, 

and irrigation method used. Alfalfa, pasture, grains, potatoes, 

onions, and garlic represented the predominant crop types, 

but mint, sunflowers, strawberries, and sugar beets also 

were grown. Crop-water requirements were derived using 

published data (Cuenca and others, 1992), evapotranspiration 

(ET) totals recorded at Bureau of Reclamation Agrimet sites 

in Klamath Falls and Worden, and information provided 

by State and county agricultural agencies. The irrigation 

seasons for certain crop types were determined from Agrimet 

data, interviews with county and State agricultural agencies, 

and from published crop reports by the U.S. Department of 

Agriculture (2004). Sprinkler application efficiency rates 

were not field measured but obtained from published sources, 

including King and others (1978) and from communication 

with State agricultural agents. Efficiencies assigned ranged 

from 45 percent for gravity systems, to 75 percent for most 

center pivots, to 90 percent for drip systems. Most groundwater irrigation was done using sprinkler systems. The average 

application efficiency was estimated to be about 72 percent. 

Withdrawals were computed by dividing the crop-water 

requirements by the irrigation method efficiency.

On lands with primary surface-water rights (outside of 

irrigation districts) and supplemental ground-water rights, the 

wells were assumed to have been used and were assigned 50 

percent of the computed total irrigation requirement. About 

620 acres with supplemental ground-water rights outside 

of irrigation districts were estimated to have been irrigated 

in 2000. This estimate may be conservative for reasons 

previously listed.

During the 2000 irrigation season, an estimated 150,000 

acre-ft of ground water was pumped to irrigate about 59,600 

acres (table 4 and fig. 18). In Oregon, 19,200 acres were 

irrigated with ground water (about 32 percent of the total), 

and 40,400 acres (68 percent of the total) were irrigated with 

ground water in California. Withdrawals in the Butte Valley 

were about 75,600 acre-ft, or 50 percent of the total in the 

upper Klamath Basin. All withdrawals for this subbasin were 

in California. Pumpage in the upper Lost River subbasin, 

which includes Swan Lake, Langell, Yonna, and Poe Valleys 

in Oregon, totaled about 28,800 acre-ft, or 19 percent of the 

total withdrawals. All irrigated acres for this subbasin were 

in Oregon. In the Sprague River Basin, approximately 11,600 

acre-ft of water was pumped, about 8 percent of the total 

pumpage in the study area. Pumpage in the lower Lost River 

and Lower Klamath Lake subbasin, which span both States, 

totaled about 28,600 acre-ft, or about 19 percent of the total 

pumpage. Ground-water pumpage for irrigation in the Wood 

River subbasin totaled only about 1,100 acre-ft.

Table 4. Estimated ground-water pumping for irrigation in the 

upper Klamath Basin, Oregon and California, during water year 

2000.

Subbasin

Area irrigated 

with ground water 

(acres)

Estimated 

pumpage 

(acre-feet)

Upper Williamson River 2,100 4,600

Sprague River 4,300 11,600

Wood River 360 1,100

Upper Lost River 10,500 28,800

Lower Lost River 4,700 11,500

Lower Klamath Lake 5,600 17,100

Butte Valley 32,000 75,600

Total (rounded) 59,600 150,000

Ground-Water Hydrology 39
OR19-0048_fig18

See table of contents for mapping sources

Butte

Creek

Shasta River

Jenny

Cr

Fall

Cr

Little Shasta River

River

Lost

Sycan

River

Wood

River

River

Williamson

Annie

Sand

Creek Sun

Creek

Creek

Willow

Miller Cr

Boles

Creek

Creek

Lost

River

River

River

River

Sprague

S Fork

N Fk

Sprague

Sprague

Klamath

River

Upper

Klamath

Lake

Summer Lake

Agency

Lake

Lake

of the

Woods

Lake 

Ewauna John C. Boyle Reservoir

Copco

Lake

Iron

Gate

Res Tule

Lake

Sump

Lower

Klamath

Lake Clear

Lake

Res

Gerber

Reservoir

42°00'

41°30'

43°15'

43°00'

122°00' 121°00'

120°45'

45'

45'

15'

45'

30'

30'

15' 122°30' 15'

5 0 5 10 15 20 MILES

Scale 1:1,000,000

5 0 5 10 15 20 KILOMETERS

31

31 138

138

230

140

140

139

299

62

62

70

66

66

97

97

5

Silver

Lake

Road

Chemult

Beaver

Marsh

Diamond 

Lake

Clearwater

Tokatee

Falls

Silver

Lake

Summer

Lake Lenz

Kirk

Chiloquin

Klamath

Agency

Fort

Klamath

Crater Lake Union

Creek

Prospect

Cascade

Gorge

Butte

Falls Rocky

Point Modoc

Point

Klamath Falls

Lincoln

Pinehurst Keno Midland

Montague

Worden

Dorris Tulelake Langell

Valley

Malin

Merrill

Henley

Altamont

Olene

Dairy

Bonanza

Lorella

Sprague

River

Beatty

Bly

Quartz

Mountain

Study area

boundary

EXPLANATION

Area with primary 

ground-water rights 

in Oregon

Area irrigated with 

ground water in 2000

Irrigated area within 

the Bureau of 

Reclamation’s 

Klamath Project

K L A M AT H

D O U G L A S

L A K E

M O D O C

S I S K I Y O U

J A C K S O N

Whitney

Creek

Bogus

Edge Cr

Dry Cr

Larkin

Creek

Mill Cr

Pit River

Klamath

Strait

Keno

Dam Lost River 

Diversion

Channel

Winter Ridge

Coleman Rim

Barns Rim

Mt

McLoughlin

Mount

Thielsen

Modoc Plateau

Sheepy Ridge

Bryant Mountain

Bly Ridge

Sycan

Marsh

Taylor

Butte Solomon

Butte

Pelican

Butte

Yainax

Butte

Gearhart

Mountain

Spodue

Mountain

Bly

Mt

Butte

Valley

Red Rock Valley

Chiloquin

Narrows

Rocky

Ford

Wildhorse

Ridge

Torrent

Spring

Kamkaun

Spring

Whitehorse Spring

McReady

Spring

Medicine

Lake

Volcano

Klamath Hills

Klamath Valley

Yonna Valley

Swan Lake Valley

Yamsay

Mountain

Klamath

Marsh

OREGON

CALIFORNIA

Figure 18. Areas irrigated with ground water in the upper Klamath Basin, Oregon and California, during the 2000 water year, 

and areas with primary ground-water irrigation rights in Oregon.

40 Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California
ACRES, IN THOUSANDS

0

25

50

75

100

125

175

150

1940194519501955196019651970197519801985199019952000

All ground-water irrigated acres (Oregon only)

Acres with primary rights (Oregon only)

Acres with supplemental rights (Oregon only)

Figure 19. Growth in total acreage with ground-water irrigation rights (primary and supplemental) in the upper 

Klamath Basin in Oregon through 2005.

Recent Increases in the Rate of Ground-Water 

Pumping

The number of acres irrigated with ground water in the 

Oregon part of the upper Klamath Basin increased by about 

1,800 acres per year between 1950 and 2000. Figure 19

shows that the total acres in the Klamath Basin with primary 

ground-water rights in Oregon increased slowly with time, 

with periodic larger increases associated with droughts in the 

late 1960s, late 1970s, and early 1990s. Historical information 

on ground-water use in California was not readily available. 

Ground-water withdrawal in the entire upper Klamath 

Basin during water year 2000 is estimated to have been 

about 150,000 acre-ft (table 4). The amounts of historical 

supplemental ground-water pumping are not known, but 

generally are assumed to be a fraction of the total amount 

pumped. The number of acres with supplemental ground-water 

rights is less than one-half the number with primary rights, and 

supplemental ground-water use presumably occurs only during 

dry years or parts of irrigation seasons when surface water is 

not available.

Since 2001, there has been a marked increase in groundwater pumping in the upper Klamath Basin in response 

to changes in surface-water management and to a series 

of consecutive dryer-than-average years. The increase is 

largely due to government programs such as Reclamation’s 

ground-water acquisition program in 2001 and pilot water 

bank in 2003, 2004, and 2005 designed to augment surfacewater supplies. The pilot water bank was mandated by the 

2002 NOAA Fisheries Biological Opinion (National Marine 

Fisheries Service, 2002) regarding operation of the Klamath 

Project and its effects on Klamath River coho salmon. 

Pumping for Reclamation programs, which accounts for 

most the new use, is metered and therefore reasonably well 

quantified. The amounts of pumping related to Reclamation 

programs are shown in table 5. Flow-meter data provided to 

Reclamation by well owners indicates that the total amounts 

of ground water pumped for the water bank in 2003 and 2004 

were approximately 55,700 and 75,800 acre-ft respectively. 

The reported pumpage for the water bank in 2003 represents a 

41-percent increase over the estimated pumping during 2000 

in the upper Klamath Basin. The 2004 pumpage represents 

a 56-percent increase. The spatial distribution of 2003 and 

2004 water-bank pumping is shown in figure 20. Most of this 

increased pumping (about 61,000 acre-ft) was in the lower 

Lost River and Lower Klamath Lake subbasins. Ground-water 

pumping in this area prior to 2001 is estimated to be about 

28,600 acre-ft. Therefore, the additional 61,000 acre-ft of 

water-bank pumping during 2004 represents an approximate 

3-fold increase in the total ground-water use in that area. The 

response to this increased pumping is discussed in the section 

on hydraulic head fluctuations.

Ground-Water Hydrology 41
Hydraulic Head Distribution and Ground-Water 

Flow Directions

Hydraulic head provides the driving force for groundwater flow. Ground water flows from areas of high head 

toward areas of low head. The change of head with distance 

is referred to as the “head gradient.” In the uppermost parts of 

aquifer systems, the head generally follows topography and 

is highest in upland areas, where recharge typically occurs, 

and lowest in lowland areas, where ground water typically 

discharges to streams. Hydraulic head often changes with 

depth as well as horizontally, so ground-water movement 

typically includes a vertical component of flow. Vertical head 

gradients are downward in recharge areas; as a result, the 

elevation of the static (nonpumping) water levels in wells in 

recharge areas decreases (becomes deeper) with increasing 

well depth. Head gradients are typically upward in discharge 

areas, causing the elevation of the static water levels in wells 

to increase (become shallower) with increasing well depth. 

If an upward vertical gradient is sufficient, wells of a certain 

depth may flow at the surface. Flowing artesian wells are 

common in parts of the Wood and Sprague River subbasins.

Knowing the distribution of hydraulic head is critical to 

understanding the directions of ground-water flow. Figure 21

shows the generalized hydraulic head distribution in the 

upper Klamath Basin. Information used to map hydraulic 

head is obtained from water wells, springs, and streams. 

The static water level in a well represents the hydraulic 

head in the aquifer at the depth of the open interval of the 

well. Water levels in wells open to more than one aquifer, 

or to large vertical thicknesses in a single aquifer, represent 

an average of the heads in the open interval. Springs also 

provide information on hydraulic head distribution, as springs 

represent places where the water table intersects land surface. 

Large-volume springs provide useful information on the head 

in the regional ground-water flow system. Stream reaches 

that gain flow from ground-water discharge also provide 

information on the hydraulic head distribution of the groundwater system. Streams that gain large volumes of water due to 

ground-water inflow are at or below the elevation of the head 

in the adjacent aquifer system. The mapping of the hydraulic 

head distribution in the upper Klamath Basin relied upon data 

from all of these sources. Water level measurements from 

approximately 1,000 field-located water wells provided most 

of the detailed information in populated parts of the basin. In 

sparsely populated and unpopulated parts of the basin, where 

wells are scarce, springs provided much of the information. 

Spring elevations generally were obtained from 1:24,000-

scale topographic maps. Gaining stream reaches were used to 

constrain head elevations in the Williamson River drainage, 

Wood River Valley, and in the Klamath River canyon below 

John C. Boyle Dam. Heads shown on figure 21 in the Lost 

River subbasin from the outlet of Clear Lake Reservoir 

(Malone Dam) to Olene Gap were modified from Grondin 

(2004), and contours in the Butte Valley area were modified 

from Wood (1960).

The head distribution depicted in figure 21 is a 

generalization. Limited available data prevented mapping 

all the complexities of the true head distribution. The map 

depicts the top of the saturated zone as closely as possible, 

and generally represents the water-table surface. For low-lying 

areas, the map is based on static water levels in wells and may 

not reflect water levels in temporarily saturated soil horizons 

in irrigated areas. For the Wood River subbasin, the map 

was drawn using wells penetrating an artesian aquifer, where 

the heads are locally above land surface. Contours are most 

detailed and have the smallest intervals in areas where data are 

plentiful, and more generalized with large intervals where data 

area sparse.

The highest water-level elevations in the upper Klamath 

Basin occur in the principal recharge areas. These include the 

Cascade Range, the highland around Medicine Lake Volcano, 

and uplands along the eastern margin of the basin, including 

Yamsay Mountain, Winter Ridge, Gearhart Mountain, and 

Coleman and Barns Rims. Ground water flows from the 

Cascade Range eastward toward the lower elevations of the 

basin. From Crater Lake, head gradients are toward Klamath 

Marsh and southeastward toward the Wood River valley. 

South of Crater Lake, ground water flows eastward toward 

the Wood River Valley and Upper Klamath Lake. Where the 

Klamath River cuts through the Cascade Range, ground-water 

flow is generally parallel to the axis of the range and toward 

the river. From the Medicine Lake highlands, ground water 

flows generally northward toward Butte Valley and the Lower 

Klamath and Tule Lake subbasins. Head gradients along the 

eastern margin of the basin are generally westward. From 

Yamsay Mountain, ground water flows westward toward the 

upper Williamson River, and southeastward toward Sycan 

Marsh. Ground water flows from the Gearhart Mountain area 

generally southwestward toward the Sycan and Sprague River 

drainages. From the Barns Rim area, ground water flows 

generally toward Gerber Reservoir and the upper Lost River. 

In the Modoc Plateau area east and south of Clear Lake, head 

gradients slope westward toward the Tule Lake subbasin.

Table 5. Ground-water pumping for the Bureau of Reclamation 

pilot water bank and ground-water acquisition program, upper 

Klamath Basin, Oregon and California.

[Data from Bureau of Reclamation and Oregon Water Resources Department. 

Values in acre-feet]

Source

Water year

2001 2002 2003 2004

Reported pumpage from 

private wells1

59,000 0 38,900 62,900

Pumpage from Tule Lake 

Irrigation District wells

10,300 18,600 16,800 12,900

Total2 69,300 18,600 55,700 75,800

1

 Includes some irrigation district wells in Oregon.

2

 Totals include only pumpage related to government sponsored programs.

42 Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California
OR19-0048_fig20a

Lower 

Klamath

Lake

Upper 

Klamath

Lake

KLAMATH

RIVER

122°00' 45' 30' 121°15'

42°00'

42°15'

41°45'

0 5 10 15 MILES

0 5 10 KILOMETERS

See table of contents for mapping sources

OREGON

CALIFORNIA

 EXPLANATION

2003 annual estimated pumpage— 

In acre-feet per well included 

 in the water bank

 0–250

 251–750

 751–1500

 1501–3000

 More than 3000

River

Lost

Miller Cr

Lost

River

Sprague River

Lake

Ewauna

Tule

Lake

Sump Clear

Lake

Res

Modoc

Point

Klamath Falls

Keno Midland

Worden

Dorris Tulelake

Langell

Valley

Merrill Malin

Henley

Altamont

Olene

Dairy

Bonanza

Lorella

Sprague

River Beatty

Klamath

Strait

Keno

Dam

Lost River 

Diversion

Channel

Sheepy Ridge

Bryant Mountain

Bly Ridge

Yainax

Butte

Bly

Mt

Butte

Valley

Klamath Hills

Klamath Valley

Swan Lake Valley

Figure 20. Distribution of ground-water pumping for the Bureau of Reclamation pilot water bank during water years 2003 and 

2004, upper Klamath Basin, Oregon and California. (Data from Reclamation water bank records and OWRD meter readings.)

Ground-Water Hydrology 43
OR19-0048_fig20b

Lower 

Klamath

Lake

Upper 

Klamath

Lake

KLAMATH

RIVER

122°00' 45' 30' 121°15'

42°00'

42°15'

41°45'

0 5 10 15 MILES

0 5 10 KILOMETERS

See table of contents for mapping sources

OREGON

CALIFORNIA

 EXPLANATION

2004 annual estimated pumpage— 

In acre-feet per well included 

 in the water bank

 0–250

 251–750

 751–1500

 1501–3000

 More than 3000

River

Lost

Miller Cr

Lost

River

Sprague River

Lake

Ewauna

Tule

Lake

Sump Clear

Lake

Res

Modoc

Point

Klamath Falls

Keno Midland

Worden

Dorris Tulelake

Langell

Valley

Merrill Malin

Henley

Altamont

Olene

Dairy

Bonanza

Lorella

Sprague

River Beatty

Klamath

Strait

Keno

Dam

Lost River 

Diversion

Channel

Sheepy Ridge

Bryant Mountain

Bly Ridge

Yainax

Butte

Bly

Mt

Butte

Valley

Klamath Hills

Klamath Valley

Swan Lake Valley

Figure 20.—Continued.

44 Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California
OR19-0048_fig21

See table of contents for mapping sources

Butte

Creek

Shasta River

Jenny

Cr

Little Shasta River

River

Lost

Sycan

River

Wood

River

River

Williamson

Annie

Sand

Creek Sun

Creek

Creek

Willow

Miller Cr

Boles

Creek

Creek

Lost

River

River

River

River

Sprague

S Fork

N Fk

Sprague

Sprague

Sheep

Creek

Klamath

River

Upper

Klamath

Lake

Summer Lake

Agency

Lake

Lake

of the

Woods

Lake Ewauna

John C. Boyle Reservoir

Copco

Lake

Iron

Gate

Res Tule

Lake

Sump

Lower

Klamath

Lake Clear

Lake

Res

Crater

Lake

Gerber

Reservoir

42°00'

41°30'

43°15'

43°00'

122°00' 121°00'

120°45'

45'

45'

15'

45'

30'

30'

15' 122°30' 15'

5 0 5 10 15 20 MILES

Scale 1:1,000,000

5 0 5 10 15 20 KILOMETERS

31

31 138

138

230

140

140

139

299

62

62

70

66

66

97

97

5

Silver

Lake

Road

Chemult Diamond 

Lake

Silver

Lake

Summer

Lake Lenz

Kirk

Chiloquin

Klamath

Agency

Fort

Klamath

Crater Lake

Prospect

Butte

Falls Rocky

Point Modoc

Point

Klamath Falls

Pinehurst Keno

Dorris Tulelake Langell

Valley

Malin

Merrill

Olene

Dairy

Bonanza

Lorella

Sprague

River

Beatty

Bly

Study area

boundary

K L A M AT H

D O U G L A S

L A K E

M O D O C

S I S K I Y O U

J A C K S O N

Whitney

Creek

Bogus

Edge Cr

Dry Cr

Larkin

Creek

Mill Cr

Pit River

Klamath

Strait

Keno

Dam

Lost River 

Diversion

Channel

Winter Ridge

Coleman Rim

Barns Rim

Mt

McLoughlin

Mount

Thielsen

Modoc Plateau

Sheepy Ridge

Bryant Mountain

Bly Ridge

Sycan

Marsh

Taylor

Butte Solomon

Butte

Pelican

Butte

Yainax

Butte

Gearhart

Mountain

Spodue

Mountain

Bly

Mt

Butte

Valley

Red Rock Valley

Chiloquin

Narrows

Rocky

Ford

Wildhorse

Ridge

Torrent

Spring

Kamkaun

Spring

Whitehorse Spring

McReady

Spring

Medicine

Lake

Volcano

Klamath Hills

Klamath Valley

Yonna Valley

Swan Lake Valley

Yamsay

Mountain

Klamath

Marsh

Brown

Spring

Wickiup

Spring

Miller

Creek

The

Gap

Poe Valley

Stukel

Mountain Fall

Creek

OREGON

CALIFORNIA

5000

4800

4700

4600

4500

4300

4400

4200

4100 4020

4080

4120

4120

4120

4100

4000

4220

4240

4220

4200

4400

4600

4120

4120

4080

4060 4040

5000

5000

4200

4000

3000

3000

5000

5500

5500

5500

6000

5000

4340

4400

4140

4140

4140

4160

4180

4400 4280

4300

4500

4900

4800

5500

5000

6000

5000

5500

4500

4520

4700

4600

4800

4540

4600

5000

6000

4000

4200

4800

4100

5000

4200

4140

6000

EXPLANATION

Equal elevation of water 

level contour— 

Interval of solid lines is 

100, 200, 500, and 1,000 

feet. Interval of dotted 

lines is 20 feet. Datum 

is NGVD 1929.

Direction of groundwater flow

Well with water-level 

measurements

5500

4540

Figure 21. Generalized water-level contours and approximate directions of regional ground-water flow in the upper Klamath 

Basin, Oregon and California.

Ground-Water Hydrology 45
Sprague River Subbasin

Hydraulic head data in the Sprague River subbasin are 

largely limited to valley bottoms and are sparse in upland 

areas. Head data from wells and springs indicate regional 

ground water flows generally westward from upland areas 

around Gearhart Mountain. Between Bly and Beatty, ground 

water flows toward the valley from local recharge areas around 

Yainax Butte. Ground water also flows toward this part of the 

valley from the north. These head gradients are consistent with 

the observed ground-water discharge to the river between Bly 

and Beatty. Head data also show ground water flowing toward 

the Whisky Creek area from Yainax Butte and Bly Mountain. 

Ground water discharges to streams in the Whisky Creek area. 

The general pattern of ground-water flow toward the valley 

occurs over most of the length of the Sprague River, although 

discharge occurs only at specific locations. An upward vertical 

head gradient occurs locally in the Sprague River Valley. 

Numerous flowing artesian wells have been mapped in the 

area between Beatty and the town of Sprague River (Leonard 

and Harris, 1974). The localized artesian aquifer consists of 

volcanic, fluvial, and volcaniclastic deposits confined by finegrained lacustrine deposits.

Wells are sparse in the Sycan River subbasin, so 

ground-water flow directions are inferred mostly from spring 

altitudes and topography. Ground water appears to flow from 

Winter Ridge and uplands south of Sycan Marsh generally 

westward. Ground water flows southeastward toward the 

Sycan River subbasin from Yamsay Mountain. North of 

Spodue Mountain, the head gradient is generally northward 

toward the Sycan River. This is consistent with the groundwater discharge at Torrent Spring. West and south of Spodue 

Mountain, ground water flows generally southward toward 

the Sprague River subbasin. Piezometer data from Sycan 

Marsh show a downward head gradient over most of the area 

(Leslie Bach, The Nature Conservancy, oral commun., 2005). 

At the northern end of Sycan Marsh an area on the valley 

floor contains numerous springs, indicating that upward head 

gradients occur locally.

Williamson River Subbasin

The Williamson River originates near Taylor Butte and 

flows generally northward between Yamsay Mountain and 

the faulted volcanic upland to the west. Two local recharge 

areas exist in the upper Williamson River drainage. Head 

data from wells and springs, along with precipitation data, 

indicate that Yamsay Mountain is a significant local recharge 

area and that ground water flows westward from Yamsay 

Mountain toward the upper Williamson River. Head data, 

mostly from springs, indicates that the faulted upland west 

of the uppermost Williamson River also is an area of local 

recharge, and that ground water flows from that area eastward 

toward the Williamson River. Head gradients sloping toward 

the Williamson River from both of these recharge areas causes 

the river to gain flow due to ground-water discharge in its 

uppermost reaches.

Data from wells and springs show that the head gradient 

slopes toward Klamath Marsh from recharge areas in the 

Cascade Range. Out on the broad plain east of the Cascade 

Range, the water table is relatively flat, sloping gently toward 

the marsh. Ground-water flow directions between Klamath 

Marsh and Kirk are poorly understood due to the lack of 

data. South of Kirk and west of Solomon Butte, a substantial 

southward head gradient exists, indicating that ground water 

flows from this area toward major discharge (spring) areas 

along the lower Williamson River and tributaries. Ground 

water also appears to flow south of Solomon Butte toward 

discharge areas along the lower Sprague River.

Upward vertical gradients are apparent locally in spring 

areas near the headwaters of the Williamson River and west 

of Klamath Marsh, where numerous flowing artesian wells 

have been mapped. Downward head gradients are apparent in 

well data along the Williamson River near Sheep Creek and in 

uplands north of the marsh. Well 28S/09E-20BAB northwest 

of the marsh had a water-level altitude of about 4,510 ft in July 

2006, below the altitude of nearby springs and at roughly the 

same altitude as the marsh. The water level altitude in well 

28S/10E-27DBD was about 4,503 ft in April 2006, several feet 

below the water level in the marsh. This raises the possibility 

of subsurface drainage of the northern part of Klamath Marsh, 

at least during dry climate cycles.

The lower Williamson River (below Kirk) is one of the 

most significant ground-water discharge areas in the upper 

Klamath Basin. Between its descent from Kirk and the point 

where it emerges onto its delta, the Williamson River is largely 

confined to a relatively narrow valley. Head gradients slope 

toward the Williamson River in this area from the east and 

west

Upper Klamath Lake Subbasin

Well and spring data show that the head gradient 

slopes eastward from the Cascade Range toward the Wood 

River Valley north of Upper Klamath Lake. Consequently, 

many streams emerging from the Cascade Range have large 

baseflow, and several large springs discharge at the western 

edge of the valley. A steep gradient toward the basin from the 

east indicates the potential for ground-water flow across the 

bounding escarpments from uplands immediately to the east. 

This gradient from the east appears to extend southward at 

least to Modoc Point.

A southward hydraulic head gradient from Crater Lake 

extends to the northern edge of Agency Lake. Between Crater 

Lake and the northern end of the Wood River Valley, the 

gradient is 100 to 300 ft/mi. The gradient decreases to about 

40 ft/mi from the northern end of the valley to the area of 

Fort Klamath, where the gradient continues south at less than 

46 Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California
5 ft/mi. The head altitudes shown in the Wood River Valley 

on figure 21 represent water bearing strata (generally sand 

and pumice) in the upper 100–300 ft of the basin-fill deposits. 

These strata are overlain and confined by clay layers, resulting 

in artesian conditions, with heads above land surface over 

much of the area. This is the principal developed aquifer in the 

Wood River Valley.

Little head data exist for the ridge east of Upper Klamath 

Lake; however, springs along the margin of Upper Klamath 

Lake indicate a head gradient toward the lake, consistent 

with the area to the north. Head data in the Rocky Point area 

indicate a gradient toward the lake ranging from more than 

100 ft/mi in the Cascade Range to about 15 ft/mi on the valley 

floor. The gradients toward Upper Klamath Lake from the 

north, east, and west suggest that ground water is discharging 

to the lake. South of Upper Klamath Lake, however, the head 

gradient slopes southeastward toward the Klamath River 

Valley and the Lower Klamath Lake subbasin.

Upper Lost River Subbasin

Much of head data and analysis for the upper Lost River 

subbasin are from Grondin (2004). The Lost River originates 

at Clear Lake Reservoir and winds through a complex of 

interconnected structural basins north to Bonanza, west to 

Olene Gap, and then generally southwestward to Tule Lake. 

Head gradients indicate that ground water flows generally 

toward the upper Lost River Valley from regional recharge 

areas to the east and from local recharge associated with 

Bryant Mountain and other uplands surrounding the subbasin. 

Although data are scarce, ground water appears also to flow 

from recharge areas associated with uplands around Yainax 

Butte and Bly Mountain. The hydraulic head gradient is 

exceedingly flat in the alluvial valleys of the upper Lost River 

subbasin; however, the water-table surface likely is variably 

influenced by pumping. Although the head gradient in the 

valley is small, it does indicate that ground water moves 

generally down valley.

Ground-water flow directions in structural valleys 

adjacent to the upper Lost River subbasin, such as Swan Lake 

and Yonna Valleys, appear to be generally toward the Lost 

River. One exception is the southernmost Poe Valley, where 

the head gradient slopes steeply southward toward the Tule 

Lake subbasin. Another exception is the southern part of 

Swan Lake Valley, where the gradient appears to slope steeply 

toward the southwest. The path that ground water follows 

out of the southwestern margin of the Swan Lake Valley is 

unclear, but most likely it is southward toward Olene Gap.

Vertical head gradients are variable in the upper 

Lost River subbasin. Grondin (2004) evaluated well log 

information, geophysical data, and water-level measurements, 

and found downward vertical gradients between basin-fill 

sediments and the underlying basalt to be common along 

valley margins and upward gradients in valley centers in 

the eastern Lost River subbasin. Vertical gradients within 

the sedimentary section or the basalt were not common. 

Downward vertical gradients were observed in the Swan 

Lake Valley, but heads in that area generally were above the 

elevation of the Lost River.

Klamath Valley

The Klamath Valley area comprises the Lost River 

drainage from Olene Gap to about Merrill and includes the 

area immediately south of Klamath Falls and northeast of 

the Klamath Hills. Ground water flows into the Klamath 

Valley from the area of Klamath Falls and the uplands to the 

southwest. Ground water also flows into the Klamath Valley 

from uplands to the northeast and the Olene Gap area. Local 

recharge creates a gradient toward the valley from the Klamath 

Hills as well. Within the Klamath Valley, ground water flows 

southeastward toward the Tule Lake subbasin. Head gradients 

on the valley floor are low, averaging 2–3 ft/mi. Southeast of 

Merrill and north of Sheepy Ridge, the head gradient steepens 

to about 20 ft/mi. This steepening coincides with a possible 

subsurface extension of Sheepy Ridge and the margin of the 

Tule Lake structural basin.

Butte Valley/Red Rock Valley Area

Butte Valley is an internally drained structural basin. 

The head distribution in the Butte Valley area shown on 

figure 21 is modified from Wood (1960) and augmented in 

adjacent uplands using additional well and spring data. Since 

the creation of Wood’s (1960) water-table map, water levels 

have declined in parts of Butte Valley as much as 15–25 ft in 

response to pumping and climate. Declines occurred primarily 

during 1975–1990 and since 2000. The declines appear to be 

localized, as water levels have been stable in other parts of 

Butte Valley. Localized declines since the 1950s have changed 

the configuration of the water-table surface in Butte Valley, 

but have not changed the overall regional ground-water flow 

directions.

Head data show a steep gradient toward Butte Valley 

from volcanic uplands to the south and west. Gradients from 

the uplands to the south and around Medicine Lake Volcano 

range from 100 to 300 ft/mi. In the lower elevation parts of the 

Butte Valley/Red Rock Valley area, gradients flatten markedly 

to less than a few feet per mile. Water-table altitudes are 

between 4,200 and 4,230 ft over much of this area. The watertable surface is not smooth, but is affected by local geology, 

surface-water hydrology, and pumping. There is a regional 

northeastward slope to the gradient, indicating ground-water 

flow from the Butte Valley/Red Rock Valley area toward the 

Lower Klamath Lake subbasin across the intervening uplands. 

The gradient steepens beneath the intervening uplands to 

roughly 50 ft/mi.

Ground-Water Hydrology 47
Lower Klamath Lake Subbasin

Lower Klamath Lake occupies a structural basin bounded 

roughly by the Klamath River, the Klamath Hills, uplands 

to the southwest, and Sheepy Ridge. Hydraulic head data 

(fig. 21) indicate ground-water flow toward Lower Klamath 

Lake from uplands just north of the Klamath River. There also 

is flow from the Butte Valley/Red Rock Valley area southwest 

of the basin. Heads in the Lower Klamath Lake subbasin and 

Klamath Valley are similar; however, in the Klamath Hills, 

which separate the two subbasins, heads are slightly higher, 

indicating local recharge or regional discharge. The higher 

heads cause a small gradient toward the Lower Klamath Lake 

subbasin from the Klamath Hills.

The hydraulic head gradient is very small on the 

floor of the Lower Klamath Lake subbasin, sloping gently 

southeastward at 1 to 2 ft/mi over most of the area. East of 

the Lower Klamath Lake, near Sheepy Ridge, the gradient 

steepens to approximately 16 ft/mi toward the Tule Lake 

subbasin, indicating ground-water flow in that direction. This 

is consistent with isotopic data from deep wells in the Tule 

Lake subbasin, which indicate the deep aquifer there contains 

a fraction of water from the Lower Klamath Lake subbasin 

(Palmer and others, 2007).

Tule Lake Subbasin

Hydraulic head data from wells shows that ground 

water flows toward the Tule Lake subbasin from the north, 

east, and west. Ground water flows from the north from the 

Klamath Valley and southernmost Poe Valley. Ground water 

flows eastward from the Lower Klamath Lake subbasin into 

the Tule Lake subbasin as described in the preceding section. 

A relatively steep gradient of up to 100 ft/mi toward the 

Tule Lake subbasin occurs in the Clear Lake area and on the 

Modoc Plateau to the south. The ground-water flow directions 

inferred from hydraulic head gradients are consistent with 

isotopic data that suggest that water produced by deep wells 

in the Tule Lake subbasin originated as recharge in the interior 

and eastern parts of the upper Klamath Basin with a probable 

component of water from the Lower Klamath Lake subbasin 

(Palmer and others, 2007). Head gradients are small on the 

valley floor, being less than 1 ft/mi in much of the area. 

Analysis by CDWR (Eaves and others, 2002) indicates that 

the head gradients in lavas underlying basin-filling sediments 

slope gently toward the south at 2.5 ft/mi or less. Gradients 

are much smaller in the shallow water-bearing zones in the 

sedimentary section, and are generally toward the Tule Lake 

Sump. Head data from wells indicate ground-water flow 

southward out of the Tule Lake subbasin, east of Medicine 

Lake Volcano, toward the Pit River Basin south of the study 

area.

Subsurface drainage from the Tule Lake subbasin is 

consistent with historical observations in the area, many of 

which were summarized by La Rue (1922). Much of this 

evidence was manifest prior to the draining of Tule Lake, 

which covered an area of about 150 mi2

 prior to draining 

(according to a 1905 Reclamation survey map). La Rue cited 

Native American accounts of a whirlpool in the lake, and 

stated that at high stage water discharged into lava flows along 

the southern margin (a phenomenon common in the lavas 

of central Oregon). Early efforts to drain the lake included 

construction of pits in the lava designed to act as drains. La 

Rue noted that silt deposits in the lava slope southward, away 

from the lake. He also considered the fact that “waters of Tule 

Lake are fresh and the lake bed comparatively free of salts” as 

proof that the lake “in the past had an outlet.”

Klamath Canyon Area

The Klamath Canyon area includes the reach of the 

Klamath River between John C. Boyle and Iron Gate Dams. 

Along most of this reach, the river occupies a steep-walled 

canyon as it cuts through the Cascade Range. The canyon 

widens between the upper end of Copco Lake reservoir and 

Iron Gate Dam, becoming narrow again downstream. Data 

from sparse wells and numerous springs indicate that ground 

water flows toward the river throughout the Klamath Canyon 

area.

Fluctuations in Hydraulic Head

Hydraulic head fluctuates with time in response to 

external stresses, the most important of which are variations in 

natural recharge from precipitation, pumping, lake stage, and 

recharge from canal leakage. These fluctuations are manifest 

as variations in the water levels in wells.

Ground-water-level fluctuation data are collected by 

taking multiple water-level measurements in the same well 

over a period of time. Multiple water-level measurements 

are available for 257 wells in the upper Klamath Basin. 

Observation wells are monitored periodically by the USGS, 

OWRD, and CDWR. Wells have been monitored for periods 

ranging from less than 1 year to more than 50 years, and 

measurements have been made at intervals ranging from once 

every 2 hours (using automated recording devices) to a few 

times a year. The short-interval measurements effectively 

create a continuous record of water-level fluctuations.

Ninety-one wells in the basin have been monitored by 

OWRD, some for periods greater than 50 years. Twenty wells 

with relatively long-term (10–50 years) records currently are 

being measured by OWRD (fig. 22). Measurements in those 

wells generally are made one to four times a year. Sixty-two 

48 Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California
OR19-0048_fig22

See table of contents for mapping sources

42°00'

41°30'

43°15'

43°00'

122°00' 121°00'

120°45'

45'

45'

15'

45'

30'

30'

15' 122°30' 15'

5 0 5 10 15 20 MILES

Scale 1:1,000,000

5 0 5 10 15 20 KILOMETERS

K L A M AT H

D O U G L A S

L A K E

M O D O C

S I S K I Y O U

J A C K S O N

Brownsworth

Creek

Butte

Creek

Cr

Whitney

Creek

Shasta River

Shovel

Bogus

Cr

Jenny

Cr

Fall

Cr

Edge Cr

Little Shasta River

River

Lost

Camp Cr

Scotch Cr

Dry Cr

Spencer

Whisky

Creek

Trout Cr

Larkin

Creek

Sycan

River

Spring

Creek

Wood

River

River

Long

Creek Williamson

Annie

Scott

Creek Sand

Creek

Springs

Big

Creek

Sheep

Creek

Sun

Creek

Creek

Brown

Creek

 Creek

Mill Cr

Willow

Pit River

Miller Cr

Boles

Cr

Creek

Lost

River

River

River

River

Fork

Sprague

S Fork

N

Creek

Creek

Meryl

Fivemile

Cr

Creek

Jack

Sevenmile

Fourmile

Creek

Sprague

Sprague

Deming

Creek

Klamath

Strait

Keno

Dam Lost River 

Diversion

Channel

Creek

Rock

Klamath

River

Crater

Lake

Upper

Klamath

Lake

Summer Lake

Agency

Lake

Aspen

Lake

Lake

of the

Woods

Lake Ewauna

John C. Boyle Reservoir

Copco

Lake

Iron

Gate

Res Tule

Lake

Sump

Lower

Klamath

Lake Clear

Lake

Res

Gerber

Reservoir

Winter Ridge

Coleman Rim

Barns Rim

Mt

McLoughlin

Mount

Thielsen

Modoc Plateau

Sheepy Ridge

Bryant Mountain

Bly Ridge

Sycan

Marsh

Taylor

Butte Solomon

Butte

Pelican

Butte

Yainax

Butte

Gearhart

Mountain

Spodue

Mountain

Bly

Mt

Butte

Valley

Red Rock Valley

Chiloquin

Narrows

Rocky

Ford

Wildhorse

Ridge

Torrent

Spring

Kamkaun

Spring

Whitehorse Spring

McReady

Spring

Medicine

Lake

Volcano

Klamath Hills

Klamath Valley

Yonna Valley

Swan Lake Valley

Yamsay

Mountain Klamath

Marsh

Knot Tableland

Beatty

Gap

OREGON

CALIFORNIA

Chemult Diamond 

Lake

Silver

Lake

Summer

Lake Lenz

Kirk

Chiloquin

Klamath

Agency

Fort

Klamath

Crater

Lake

Prospect

Butte

Falls Rocky

Point Modoc

Point

Klamath Falls

Pinehurst Keno

Dorris

Macdoel

Tulelake

Langell

Valley Malin

Merrill

Olene

Dairy

Bonanza

Lorella

Sprague

River

Beatty

Bly

31

31

138

138

230

140

140

139

299

62

62

70

66

66

97

97

5

Silver

Lake

C A S C A D E

R A N G E

Road

Study area

boundary

30S/07E-06AAA

36S/14E-25BCB

35S/12E-26DCD

36S/11E-20DCA

36S/10E-14ACC

41S/14E-08CAA

39S/12E-35ADD

39S/12E-35ABB

39S/11E-26ABD

39S/11E-20AAD

40S/12E-32CDB

40S/12E-30DCB

40S/11E-11BAD

41S/09E-12AAB

40S/09E-28ADB

38S/09E-17CBC

35S/06E-10ACC

46N/01E-06N01

48N/04E-35L02

28S/09E-20BAB

28S/10E-27DBD

EXPLANATION 

Wells in the Upper Klamath 

Basin

Well monitored quarterly by 

 USGS

Well equipped with USGS 

 continuous recorder

Oregon Water Resources 

 Department observation 

 well

California Department of 

 Water Resources 

 observation well

Figure 22. Selected observation wells in the upper Klamath Basin, Oregon and California. Location information is only shown 

for wells specifically referenced in this report.

Ground-Water Hydrology 49
wells were measured quarterly during this study by the USGS 

for periods ranging from 1 to 6 years (fig. 22). Nineteen wells 

were instrumented with continuous recorders, devices that 

measure and record the water-level elevation every 2 hours. 

Graphs of water-level fluctuations in all of the wells monitored 

by the USGS are available on the USGS web site (http://

waterdata.usgs.gov/or/nwis/gw). Not all wells monitored in 

the upper Klamath Basin are shown in figure 22. Scores of 

additional wells have been or currently are monitored by the 

CDWR and the OWRD for specific purposes. Data from the 

wells shown in figure 22, which includes all wells monitored 

by the USGS, provide a comprehensive picture of the dynamic 

nature of the regional ground-water system.

Climate-Induced Fluctuations

Water levels in most wells fluctuate in response to natural, 

climate-induced changes in recharge. The greatest response 

to climate-induced water-level fluctuations in the upper 

Klamath Basin occurs in the Cascade Range. The response to 

diminished precipitation (and hence recharge) in the Cascade 

Range during the current drought cycle is exemplified by the 

hydrograph of well 30S/07E-06AAA on the lower eastern 

flank of the Crater Lake highlands (fig. 23). The water level in 

that well has declined approximately 12 ft since 2000 because 

of climate-related decreased recharge. On the eastern side of 

the basin, a similar post-2000 trend exists in well 36S/14E25BCB (fig. 24), but the magnitude of the recent decline is 

less. A comparison of these water-level fluctuations with 

precipitation at Crater Lake in the Cascade Range (fig. 24) 

shows that periods of rising ground-water levels generally 

correspond to periods of increasing precipitation, and falling 

water-levels correspond to periods of decreasing precipitation. 

Figure 24 also shows that the decadal drought cycles are 

responsible for the largest water-level fluctuations. During 

periods of abundant precipitation, the rate of ground-water 

recharge exceeds, at least temporarily, the rate of discharge. 

When ground-water recharge exceeds discharge, the amount of 

ground water in storage must increase, causing the water table 

to rise. During dry periods, in contrast, the rate of discharge 

exceeds the rate of recharge, and ground-water levels decline 

as a result.

Water table fluctuations in response to variations in 

recharge are most prominent in the Cascade Range, the 

primary recharge area. Climate-related fluctuations may be 

difficult to discern in some interior parts of the basin, for 

two reasons. First, precipitation and, hence, recharge are 

comparatively small in the interior parts of the basin, so 

climate-induced water-level fluctuations are correspondingly 

small. Second, water levels in these areas are affected by 

ground-water pumping, canal operation, and irrigation, the 

effects of which can mask the climate signal.

186

188

190

192

194

196

198

200

DEPTH TO WATER, IN FEET

2000 2001 2002 2003 2004 2005

J M M J S N J M M J S N J M M J S N J M M J S N J M M J S N J M M J S N

Figure 23. Water-level fluctuations in well 30S/07E-06AAA near Bear Creek northeast of Crater Lake, Oregon.

50 Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California
OR19-0048_fig24

CUMULATIVE DEPARTURE FROM AVERAGE PRECIPITATION, IN INCHES 

1960 1965 1970 1975 1980 1985 1990 1995 2000

0

2

4

6

8

10

12

14

16

18

20

2005

-100

-80

-60

-40

-20

0

20

40

60

80

100

DEPTH TO WATER, IN FEET

Cumulative departure from average precipitation at Crater Lake

Depth to water in well 36S/14E-25BCB

Figure 24. Water-level fluctuations in well 36S/14E-25BCB near Bly and the cumulative departure from average 

precipitation at Crater Lake, Oregon.

Pumping-Induced Fluctuations

When a well is pumped, the water table near the well 

declines due to the removal of ground water from storage. 

A conical depression centered on the well develops on the 

water table (or potentiometric surface in the case of a confined 

aquifer) and expands until it captures sufficient discharge and 

(or) induces enough new recharge to equal the pumping rate. 

After pumping ceases, the water table recovers as the aquifer 

returns to pre-pumping conditions. Key factors that determine 

the magnitude of water-table fluctuations caused by pumping 

are the aquifer characteristics, the rate and duration of 

pumping, the presence of aquifer boundaries, and the number 

of wells affecting the water table in a given area. In aquifers 

that have low permeability, pumping-induced water-table 

fluctuations can be large and even interfere with the operation 

of nearby wells. If the long-term average pumping rate exceeds 

the rate at which the aquifer can supply water, water levels will 

not recover fully and long-term water-level declines will occur.

Seasonal pumping affects many wells throughout the 

upper Klamath Basin. Water-level fluctuations from pumping 

generally range from a few feet to 20 ft. Pumping effects 

can be seen in the hydrographs for a well 35S/12E-26DCD 

near Beatty (fig. 25) and well 40S/12E-32CDB near Malin 

(fig. 26). Hydrographs for both wells have a steep drawdown 

curve during the summer followed by a broad recovery curve 

that rises throughout the winter and spring. Hydrographs for 

the wells in figures 25 and 26 also show slight year-to-year 

declines, probably due to a combination of pumping and 

climate.

Response to Canal Leakage

Water-level fluctuations due to irrigation-canal leakage 

occur in many wells throughout the irrigated areas in the 

central part of the study area, with water levels rising 

during the irrigation season when canals are flowing, and 

falling when canals are dry. The magnitude of these annual 

fluctuations varies with the proximity of the well to the 

canal, the depth of the well, and the local geology. Annual 

fluctuations due to canal leakage of more than 10 ft have been 

documented (fig. 27), although fluctuations in the range of 4 to 

5 ft are more common.

The water-level response in well 40S/09E-28ADB 

(fig. 27) is an example of canal and drain influences on wells 

open to sedimentary materials. This well is constructed into 

late Tertiary sediment on the northwest flank of the Klamath 

Hills, about 900 ft from the North Canal. The North Canal is 

diverted directly from the Klamath River and operates almost 

continuously. Although the water-level in the well responds 

to the canal operation nearly year-round, the response is 

most prevalent during the summer irrigation season. Note 

that the ground-water response to canal leakage was almost 

nonexistent in 2001, when no water flowed through the 

Klamath Project canals for most of the irrigation season 

(fig. 27).

Ground-water levels can respond rapidly to canal 

leakage, even at considerable depths, particularly in areas 

where fractured lava is the predominant rock type. Well 

39S/12E-35ABB was constructed to allow separate waterlevel measurements in two distinct water-bearing intervals. 

Ground-Water Hydrology 51
OR19-0048_fig25 DEPTH TO WATER, IN FEET

1999 2000 2001 2002 2003 2004 2005

J A J O J A J S J A J O J A J S J A J O J A J O J A J O

18

19

20

21

22

23

24

25

Figure 25. Water-level fluctuations in well 35S/12E-26DCD north of Beatty, Oregon.

DEPTH TO WATER, IN FEET

2000 2001 2002 2003 2004 2005

J M M J S N J M M J S N J M M J S N J M M J S N J M M J S N J M M J S N

145

150

155

160

165

170

175

180

Figure 26. Water-level fluctuations in well 40S/12E-32CDB northwest of Malin, Oregon.

52 Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California
The upper interval, which responds primarily to the canal 

operation, is open from 92 to 516 ft below land surface. The 

main water-bearing zone is in pyroclastic material between 

305 and 360 ft below land surface, and is overlain by lava 

flows. The water level in the upper interval of this well 

responds in a matter of days to the operation of the Langell 

Valley Irrigation District canal system (fig. 28). The water 

level starts to rise shortly after the canals start flowing, 

peaking late in the irrigation season, and dropping soon after 

canals are shut off for the season. The rapid response of the 

water table to canal leakage at such depth likely is due to rapid 

downward movement of water through interconnected vertical 

fractures in the lava flows. The lower water-bearing interval in 

the observation well is open from 950 to 1,005 ft below land 

surface, and is not influenced by canal operation. Both the 

upper and lower water-bearing zones in this well respond to 

the pumping effects of nearby wells (fig. 29). Individual wells 

can respond to both canal operation and pumping.

Response to Lake Stage

As previously discussed, ground water discharges to 

Upper Klamath Lake. The lake, therefore, represents a local 

boundary to the regional ground-water system. As a result, 

water levels in most wells near the lake track variations in 

lake stage. The water-level in well 35S/06E-10ACC (fig. 30), 

drilled on the lower northeast flank of Pelican Butte, closely 

follows the stage in Upper Klamath Lake. The well, about 

3,500 ft from the shoreline of the lake, is constructed into 

layered lava flows that are saturated below a depth of about 

470 ft (altitude 4,140). Well 38S/09E-17CBC, located near the 

Oregon Institute of Technology campus in Klamath Falls, also 

fluctuates with the stage of Upper Klamath Lake (fig. 31). The 

well is about 5,200 ft from the lake, and is constructed into 

interbedded sediment and lava to a total depth of 425 ft.

Long-Term Water-Table Fluctuations

Water levels in wells in the upper Klamath Basin that 

have been monitored for several decades show fluctuations in 

response to many of the stresses just discussed. In addition, 

measurements in most of the wells also reflect decadal scale, 

wet-dry climate cycles, with some showing the effects of 

multiyear pumping stresses. Water level trends observed near 

Bly (well 36S/14E-25BCB), Bonanza (well 39S/11E-20AAD), 

and the southern Langell Valley (well 41S/14E-08CAA) 

exemplify areas where ground-water levels are responding 

mostly to variations in recharge (climate) (fig. 32), showing 

decadal scale fluctuations of 4–5 ft.

The ground-water flow system appears to be responding 

to prolonged pumping stresses in several other areas in 

the upper Klamath Basin, including the area between the 

communities of Sprague River and Beatty, parts of Butte 

Valley, south Poe Valley and the area of the Shasta View 

Irrigation District just north of Malin, parts of west Langell 

Valley, an area east of Lorella, and the Klamath Valley.

OR19-0048_fig27 DEPTH TO WATER, IN FEET

2000 2001 2002 2003 2004 2005

J M M J S N J M M J S N J M M J S N J M M J S N J M M J S N J M M J S N 0

5

10

15

20

25

30

35

40

DISCHARGE, IN THOUSANDS OF ACRE FEET

35

37

39

41

43

45

47

49

Depth to water in well 40S/9E-28ADB01

Discharge in North Canal

Figure 27. Water-level fluctuations in well 40S/09E-28ADB on the southwest side of the Klamath Hills, Oregon, and 

monthly discharge in the nearby North Canal.

Ground-Water Hydrology 53
OR19-0048_fig28 DEPTH TO WATER, IN FEET

2000 2001 2002 2003 2004 2005

J M M J S N J M M J S N J M M J S N J M M J S N J M M J S N J M M J S N

25

30

35

40

45

50

55

60

Deep open interval

Shallow open interval

Canal system on

Canal system off

Figure 28. Water-level fluctuations in shallow and deep water-bearing zones in double-completion well 39S/12E35ABB near Lorella, Oregon.

DEPTH TO WATER, SHALLOW INTERVAL, IN FEET

DEPTH TO WATER, DEEP INTERVAL, IN FEET

APRIL MAY JUNE

2002

JULY AUGUST SEPTEMBER

25

30

35

40

45

50

51

52

53

54

55

56

Shallow open interval

Deep open interval

Figure 29. Water-level fluctuations in shallow and deep water-bearing zones in double-completion well 39S/12E35ABB near Lorella, Oregon, with time scale expanded to show effects of nearby ground-water pumping.

54 Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California
OR19-0048_fig30

1999 2000 2001 2002 2003 2004 2005

J A J O J A J S J A J O J A J S J A J O J A J O J A J O

4136

4137

4138

4139

4140

4141

4142

4143

4144

ELEVATION, IN FEET ABOVE NGVD29

Stage of Upper Klamath Lake (USGS gage 11507001)

Water level elevation in well 35S/06E-10ACC

2000 2001 2002 2003 2004 2005

J M M J S N J M M J S N J M M J S N J M M J S N J M M J S N J M M J S N

4137

4138

4139

4140

4141

4142

4143

LAKE-STAGE ELEVATION, IN FEET

4146

4147

4148

4149

4150

4151

4152

4153

WATER-LEVEL ELEVATION IN WELL, IN FEET ABOVE NGVD29

4136

Water level in well 38S/09E-17CBC

Stage of Upper Klamath Lake (USGS gage 11507001)

Figure 30. Water-level fluctuations in well 35S/06E-10ACC near Pelican Butte and stage in Upper Klamath Lake, 

Oregon.

Figure 31. Water-level fluctuations in well 38S/09E-17CBC in the north part of Klamath Falls and stage in Upper 

Klamath Lake, Oregon.

Ground-Water Hydrology 55
OR19-0048_fig32

0

2

4

6

8

10

12

14

16

18

20

19551960196519701975198019851990199520002005

DEPTH TO WATER, IN FEET

60

62

64

66

68

70

72

74

10

12

14

16

18

20

22

24

26

28

30

36S/14E-25BCB

39S/11E-20AAD

41S/14E-08CCA

Figure 32. Water-level fluctuations in wells 36S/14E-25BCB near Bly, 39S/11E-20AAD near Bonanza, and 41S/14E08CCA in the southern Langell Valley, Oregon.

56 Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California
Water levels in two observation wells near the town 

of Sprague River, 36S/10E-14ACC and 36S/11E-20DCA 

(fig. 33), have declined over 30 ft since monitoring began 

in the early 1960s. Leonard and Harris (1974) hypothesized 

that the relatively steady, and somewhat localized, longterm decline represented a loss of hydraulic head caused 

by discharge from free-flowing wells. The OWRD later 

attributed the decline, at least in part, to some wells in the 

area constructed in a manner that allowed ground water 

from a the confined basalt aquifer in the lower parts of the 

wells to flow uphole and into sedimentary units (with lower 

head) in shallower parts of the well bores (Oregon Water 

Resources Department, 1987). Borehole geophysical logging 

has confirmed the interaquifer leakage; however the geologic 

units receiving the leakage appear to be rhyolitic lavas mapped 

in the area by Sherrod and Pickthorn (1992) (Mark Norton, 

Oregon Water Resources Department, unpub. data). For 

example, geophysical logs for one nearby well show uphole 

interaquifer flow of about 200 gal/min into a unit with a 

relatively high natural gamma signature indicative of silicic 

material. The driller described the material as “broken lava 

rock.” Water levels in both wells have been more stable since 

the mid-1990s (fig. 33), likely owing to the ground-water-flow 

system beginning to reach a new equilibrium.

Water levels in long-term observation well 46N/01E06N01 in Butte Valley were stable from the 1950s to the mid1970s (fig. 34). Since 1975, the water level has declined about 

20 ft. The trend likely reflects increased pumping stresses 

during times when precipitation is low, with intermittent times 

of partial recovery during wet years in the mid-1980s and mid1990s.

An observation well in southern Poe Valley (40S/11E11BAD) shows a series of responses to development from 

which it has never fully recovered (fig. 35). Most notable is 

the water-level decline of about 20 ft between 1985 and 1995, 

a recovery of less than 5 ft between 1995 and 1998, and a 

decline of about 12 ft since 1998. Another observation well 

(40S/12E-30DCB) about 3 mi south-southeast of the Poe 

Valley well, in the area of the Shasta View Irrigation District, 

has a similar water-level trend where the records overlap from 

1994 to present (fig. 35). The total decline in well 40S/12E30DCB since 1998, however, is slightly greater at about 19 ft. 

The similarity of the head fluctuations suggests that the effects 

of pumping stresses in both areas may migrate across the 

subbasin boundary.

0

10

20

30

40

50

60

70

80

90

1960196519701975198019851990199520002005

DEPTH TO WATER, IN FEET

40

50

60

70

80

90

100

36S/10E-14ACC

36S/11E-20DCA

Figure 33. Water-level fluctuations in wells 36S/10E-14ACC and 36S/11E-20DCA in the Sprague River Valley, Oregon.

Ground-Water Hydrology 57
OR19-0048_fig34

0

10

20

30

40

50

60

70

DEPTH TO WATER, IN FEET

195019551960196519701975198019851990199520002005

46N/01E-06N01

Figure 34. Water-level fluctuations in well 46N/01E-06N01 in Butte Valley, California.

0

10

20

30

40

50

60

70

80

90

190

200

210

220

230

240

250

100

DEPTH TO WATER, IN FEET

40S/11E-11BAD

40S/12E-30DCB

195019551960196519701975198019851990199520002005

Figure 35. Water-level fluctuations in wells 40S/11E-11BAD in the southern Poe Valley and well 40S/12E-30DCB north 

of Malin, Oregon.

58 Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California
Long-term water-level trends in northwest Langell Valley 

and east of Lorella indicate that pumping stresses in those 

areas are periodically greater than average (for the area), 

probably resulting from the occasional use of supplemental 

ground-water rights. The water level in the observation well 

in northwest Langell Valley (39S/11E-26ABD) apparently 

responded to increased pumping during the 1970s, again in the 

early 1990s, and again starting in 2001 (fig. 36). The groundwater flow system nearly recovered after each of the earlier 

cycles. In 2005, the water level was about 13 ft below the level 

measured during 1998, the most recent wet period. A trend 

similar to that observed in the Langell Valley well, but with 

a smaller amplitude of fluctuation, is seen in the long-term 

record at well 39S/12E-35ADD, just east of Lorella (fig. 36). 

The 2005 water level in the Lorella well was only about 4 ft 

below the 1998 measurement. Recharge from canal leakage in 

the area may also be influencing the water-level trend in the 

Lorella well (Grondin, 2004).

Recent pumping stresses in the Klamath Valley area 

are reflected in water levels measured in observation well 

41S/09E-12AAB (fig. 37). With the exception of a sharp 

decline in 1970, the water-level trend in the well appears to 

have been in dynamic equilibrium until 2001. The increased 

pumping stresses combined with drought contributed to a 

water-level decline of about 12 ft between 2001 and 2004.

Fluctuations in Hydraulic Head in Response to 

Recent Increases in Ground-Water Pumping

Prior to 2001, the ground-water system in most of the 

upper Klamath Basin was in a state of dynamic equilibrium, 

under which water levels rose and fell in response to climate 

cycles and seasonal pumping, but generally without chronic 

long-term declines. (Water levels in some wells near the town 

of Sprague River [fig. 33] are an exception.) Historically, 

water levels declined for several years during droughts, but, 

with local exceptions, water levels eventually rose to (or 

nearly to) predrought levels during subsequent multiyear 

wet periods. Wells generally have been drilled deep enough 

and pumps set low enough to accommodate these historical 

water-level fluctuations. Pumping in the upper Klamath Basin 

increased an estimated 50 percent starting in 2001 in response 

to changes in water management and a prolonged drought. The 

ground-water system has responded to the increased pumping 

with water levels showing acute, seasonal, and long-term 

effects.

Acute effects occur close to pumping wells, generally 

within hundreds to thousands of feet. These effects typically 

are the result of the cone of depression of the pumping 

well spreading to neighboring wells, resulting in a decline 

in the static water levels, sometimes referred to as “well 

interference.” These effects typically have a rapid onset and 

dissipate relatively soon after pumping ends.

0

10

20

30

40

50

30

40

50

60

70

80

DEPTH TO WATER, IN FEET

39S/11E-26ABD

39S/12E-35ADD

195019551960196519701975198019851990199520002005

Figure 36. Water-level fluctuations in wells 39S/11E-26ABD and 39S/12E-35ADD in the western Langell Valley, Oregon.

Ground-Water Hydrology 59
Seasonal effects reflect the general lowering of the 

water table over a broad area (several square miles to tens of 

square miles) in response to the combined seasonal pumping 

of multiple wells and, in some places, seasonal variations in 

recharge. These effects typically build up over the irrigation 

season and largely recover over the following winter. 

Figure 38 shows seasonal water-level declines between spring 

and fall 2004 caused by increased pumping in the basin. Water 

levels declined more than 10 ft over more than 130 mi2 and 

more than 20 ft over about 20 mi2 during the 2004 irrigation 

season. Declines of 10–20 ft are apparent in an area extending 

from north of the Klamath Hills, through the Klamath Valley, 

into the northern and eastern parts of the Tulelake subbasin. 

Smaller areas in the Klamath Valley and the southeastern part 

of the Tulelake subbasin show seasonal water-level declines 

exceeding 20 ft in some wells. Seasonal water-level declines 

of 1–3 ft were measured in most wells distant from pumping 

centers. These widespread declines are due to natural seasonal 

fluctuation, possibly amplified by dispersed pumping and 

ongoing drought. Although a general decline in water levels 

was measured during this period, levels in some wells that 

are hydraulically connected to the shallow aquifer system in 

the basin-fill sediments rose between spring and fall, ranging 

from a fraction of a foot to as much as 3 ft. This is an annual 

occurrence entirely due to artificial recharge to the shallow 

system by canal leakage and deep percolation of irrigation 

water.

Long-term pumping effects refer to the lowering of the 

water table for more than a season, often years. Long-term 

effects can be caused by both climate and pumping stresses. 

Long-term water level declines typically occur over broad 

regions, such as an entire subbasin. Long-term decline 

generally is measured by comparing the spring high water 

levels each year. Such lowering of the water table has been 

observed over most of the upper Klamath Basin since about 

2000 because of ongoing drought. The only exception is in 

shallow aquifers in the Klamath Project area, where water 

levels are maintained by recharge from canal leakage and 

deep percolation of irrigation water. Long-term declines due 

to pumping have occurred locally in addition to this droughtrelated decline. Distinguishing pumping related declines from 

drought related declines in the basin is difficult because of the 

scarcity of data from previous drought cycles. However, near 

the town of Tulelake, where long-term water-level data exist, 

the rate of the year-to-year decline observed in the present 

drought cycle in well 48N/04E-35L02 appears to be about 

twice that observed in the most recent previous drought, from 

the late 1980s through mid-1990s (fig. 39).

OR19-0048_fig37

1960 1965 1970 1975 1980 1985 1990 1995 2000

130

140

150

160

170

180

190

2005

DEPTH TO WATER, IN FEET

41S/09E-12AAB

Figure 37. Water-level fluctuations in well 41S/09E-12AAB at the southern end of the Klamath Hills, Oregon.

60 Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California
OR19-0048_fig38

122°00' 45' 30' 121°15'

42°00'

42°15'

41°45'

0 5 10 15 MILES

0 5 10 KILOMETERS

See table of contents for mapping sources

OREGON

CALIFORNIA

Lower 

Klamath

Lake

Upper 

Klamath

Lake

KLAMATH

RIVER

 EXPLANATION

Area of water-level decline—In feet. 

 Dashed where approximately located.

 10–20

 More than 20

Measurement site

River

Lost

Miller Cr

Lost

River

Sprague River

Lake

Ewauna

Tule

Lake

Sump Clear

Lake

Res

Modoc

Point

Klamath Falls

Keno Midland

Worden

Dorris Tulelake

Langell

Valley

Merrill Malin

Henley

Altamont

Olene

Dairy

Bonanza

Lorella

Sprague

River Beatty

Klamath

Strait

Keno

Dam

Lost River 

Diversion

Channel

Sheepy Ridge

Bryant Mountain

Bly Ridge

Yainax

Butte

Bly

Mt

Butte

Valley

Klamath Hills

Klamath Valley

Swan Lake Valley

Figure 38. Water-level decline between spring and fall 2004 in the Klamath Valley and Tule Lake areas, upper Klamath Basin, 

Oregon and California.

Ground-Water Hydrology 61
OR19-0048_fig39

0

10

20

30

40

50

60

DEPTH TO WATER, IN FEET

1985 1990 1995 2000 2005

48N/04E-35L02

The year-to-year water-level declines can be evaluated 

by observing the changes in water levels between spring 2001 

and spring 2004 (fig. 40). Although data are sparse in the 

northern part of the area, measurements show that over the 

3-year period, water levels declined more than 10 ft in deep 

water-bearing zones (primarily basalt underlying basin-filling 

sediments) over more than 135 mi2 of the Klamath Valley 

and northern Tule Lake subbasin. Declines exceed 15 ft over 

an area of about 37 mi2 encompassing the State line in the 

Tule Lake subbasin and extending southward to the town of 

Tulelake and northward to Malin. Declines of 10–15 ft during 

this period are common north of Malin. Declines of 5 to 10 ft 

are common in the southeast part of the Tule Lake subbasin. 

Levels in three wells on the Modoc Plateau southeast of the 

Tule Lake subbasin declined 5 to 10 ft (fig. 40). The decline in 

this southernmost area, where no new pumping has occurred, 

is somewhat enigmatic, but may indicate that effects are 

propagating southeastward from pumping centers in the Tule 

Lake subbasin.

If the post-2000 pumping rates continue in the future, the 

regional ground-water system possibly will eventually achieve 

a new state of dynamic equilibrium. This will occur when 

the depression in the water table is large enough to redirect 

sufficient regional ground-water flow into the area to offset 

the increased pumping. At equilibrium, however, the increased 

discharge in the area of pumping must be offset by decreased 

discharge elsewhere, likely manifesting itself as a combination 

of decreased discharge to adjacent basins and decreased 

discharge to streams, lakes, and wetlands.

Certain details are readily apparent from the recently 

collected data and existing knowledge of the area. Groundwater pumping is accompanied by declines in water levels that 

occur at a variety of temporal and spatial scales. The amount 

of ground water that can be pumped in a period of time will 

be determined in part by how much drawdown water users 

and regulatory agencies will tolerate, and in part by how 

much interference with streams and lakes will be considered 

acceptable. The drawdown can be easily measured. Where 

drawdowns acutely affect individual springs, the effects on 

discharge may be easy to measure. However, where the effects 

are to larger streams or lakes and represent a small part of the 

overall flow, they usually are difficult to discriminate from 

other fluctuations by measurement. Such effects, however, can 

be calculated using computer models or analytical methods.

Figure 39. Water-level fluctuations in well 48N/04E-35L02 near the town of Tulelake, California.

62 Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California
OR19-0048_fig40

122°00' 45' 30' 121°15'

42°00'

42°15'

41°45'

0 5 10 15 MILES

0 5 10 KILOMETERS

See table of contents for mapping sources

OREGON

CALIFORNIA

Lower 

Klamath

Lake

Upper 

Klamath

Lake

KLAMATH

RIVER

 EXPLANATION

Area of water-level decline—In feet. 

 Dashed where approximately located.

 5–10

 10–15

 More than 15

Measurement site

River

Lost

Miller Cr

Lost

River

Sprague River

Lake

Ewauna

Tule

Lake

Sump Clear

Lake

Res

Modoc

Point

Klamath Falls

Keno Midland

Worden

Dorris Tulelake

Langell

Valley

Merrill Malin

Henley

Altamont

Olene

Dairy

Bonanza

Lorella

Sprague

River Beatty

Klamath

Strait

Keno

Dam

Lost River 

Diversion

Channel

Sheepy Ridge

Bryant Mountain

Bly Ridge

Yainax

Butte

Bly

Mt

Butte

Valley

Klamath Hills

Klamath Valley

Swan Lake Valley

Figure 40. Water-level decline between spring 2001 and spring 2004 in the Klamath Valley and Tule Lake areas, Oregon and 

California.

Ground-Water Hydrology 63
Summary and Discussion

The demand for water has increased in recent years in the 

upper Klamath Basin owing to changes in water management 

resulting from endangered species issues. Problems associated 

with the increased demand have been exacerbated by drought. 

As a result, interest has increased in the use of ground water 

and in understanding how the regional ground-water system 

can be utilized to prevent future water shortages. Until 

recently, key aspects of the regional ground-water system 

were not well known, and information was insufficient to 

make informed ground-water-management decisions. This 

report describes part of the results of cooperative efforts by 

the U.S. Geological Survey and the Oregon Water Resources 

Department to quantitatively characterize the regional groundwater flow system in the upper Klamath Basin to provide 

resource managers and basin residents the information needed 

to make sound resource-management decisions.

The 8,000-square-mile upper Klamath Basin is semiarid, 

with most of the basin interior receiving less than 20 inches 

per year of precipitation. Upland areas in the basin are 

mostly forested, and broad river valleys and lake basins in 

the basin interior are largely cultivated or in pasture. Irrigated 

agriculture covers roughly 500,000 acres in the basin. Of 

this area, roughly 190,000 acres are within the Bureau of 

Reclamation Klamath Project (this does not include refuge 

lands in the Project area). Most water for the Klamath Project 

comes from Upper Klamath Lake. A smaller amount of land in 

the basin is irrigated using ground water. In 2000, an estimated 

59,600 acres were irrigated using ground water.

The upper Klamath Basin spans parts of the Cascade 

Range and Basin and Range geologic provinces, and is 

underlain principally by late Tertiary and Quaternary volcanic 

rocks. The volcanic deposits in the basin are generally 

permeable and host a substantial regional ground-water 

system recharged from precipitation in the Cascade Range 

and uplands within and on the eastern margin of the basin. 

A prominent system of north to northwest trending faults 

divides the interior parts of the basin into a series of sedimentfilled structural subbasins. Ground-water flow is controlled 

by topography, distribution of recharge, the geometry of the 

stream system, and the geology. The regional geology has 

been divided into eight hydrogeologic units on the basis of 

their stratigraphic position and broad hydraulic characteristics. 

These hydrogeologic units are useful in assessing groundwater potential of specific areas.

Precipitation in the upper Klamath Basin totals 

about 10 million acre-feet per year. Most of this water 

returns to the atmosphere at or near where it falls through 

evapotranspiration. Roughly 2 million acre-feet per year enter 

the ground-water system. Most of the water that enters the 

ground-water system discharges elsewhere in the basin to 

streams, wells, or through evapotranspiration directly from the 

water table in wetlands.

An estimated 1.8 million acre-feet per year of groundwater discharges to streams. Discharge to streams occurs 

throughout the basin, but prominent areas of groundwater discharge include the flanks of the Cascade Range, 

the margins of the Wood River Valley, the area near the 

confluence of the Williamson and Sprague Rivers (including 

Spring Creek), the upper Williamson River near Yamsay 

Mountain, Bonanza Springs on the Lost River, and Klamath 

River Canyon below John C. Boyle Dam. Much of the 

ground-water discharge to streams is through major spring 

complexes. Ground water flows to streams throughout the 

year, supplying substantial water to streams in the basin. For 

decades, hydrologists have recognized that much of the water 

flowing into Upper Klamath Lake originates as ground water 

that discharges to tributary streams within 12 miles of the lake, 

or directly to the lake.

Ground-water discharge to streams is not constant, but 

varies seasonally and from year to year in response to climate 

cycles. In most large spring complexes, such as the headwaters 

of Spring Creek or the Wood River, discharge variations due 

to longer-term, decadal climate cycles are larger than seasonal 

variations. Discharge to major spring complexes, such as 

those feeding Wood River and Spring Creek may vary by a 

factor of 2. Basinwide, climate-driven ground-water discharge 

variations exceed 450 cubic feet per second, a rate that equates 

to an annual volume of 326,000 acre-feet.

Ground-water discharge from wells increased gradually 

from the late 1940s to about 2000, with small increases in 

the rate of growth related to droughts in the late 1970s and 

early 1990s. Ground-water pumpage for irrigation in 2000 

was about 150,000 acre-feet per year. Ground-water use 

increased markedly in response to water shortages in 2001 and 

subsequent water-banking efforts. As a result, ground-water 

pumpage for irrigation in 2004 was about 226,000 acre-feet 

per year.

Hydraulic head data from wells and springs shows 

that ground water flows from principal recharge areas in 

the Cascade Range and uplands in the basin interior and 

eastern margins toward discharge areas in the lake basins 

and stream valleys in the basin interior. In addition, head 

gradients indicate the potential for flow between structural 

subbasins in a generally north to south direction. Ground 

water in the upper Klamath Basin generally flows toward two 

areas of low hydraulic head: the Klamath River Canyon and 

the Tule Lake subbasin. Ground water that flows toward the 

Klamath River Canyon discharges to the river between Keno 

and John C. Boyle Dam. Some ground water that flows into 

the Tule Lake subbasin discharges there and is removed by 

evapotranspiration or pumped to the Lower Klamath Lake 

subbasin. Head gradient data indicate that some ground water 

also flows southward out of the Tule Lake subbasin basin 

toward the Pit River Basin. The amount of southward flow 

presently is not known.

64 Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California
Hydraulic head in the upper Klamath Basin fluctuates 

primarily in response to climate, pumping, canal and irrigation 

operations, and lake stage. Basinwide, climate exerts the 

largest influence on water levels. Water levels in upland areas 

have declined more than 12 feet between 2000 and 2006 in 

response to drought conditions; however, they are expected 

to rise again when wet conditions return. Because climatedriven fluctuations affect the entire basin, they have the largest 

influence on the hydrologic system and are responsible for the 

large variations in ground-water discharge to streams.

Water level fluctuations in response to pumping are most 

commonly seasonal, with the water level declining during 

the irrigation season and recovering more or less fully by 

the following spring. Prior to 2001, year-to-year water-level 

declines due to pumping were rare in the upper Klamath 

Basin. The large localized increase in pumping that began 

in 2001 has resulted in year-to-year declines in the Klamath 

Valley and Tule Lake subbasin. The total decline between 

2001 and 2004 exceeds 15 feet in parts of these areas and is 

larger than can be attributed to drought alone. These year-toyear declines have been accompanied by amplified seasonal 

declines. How long it will take water levels to recover fully 

after wet climate conditions return and pumping stress is 

reduced is not known. Data clearly show that pumping stresses 

can cause measurable head responses over broad parts of the 

ground-water system.

Irrigation and canal operation also affect water levels, 

particularly in shallow aquifers. Water levels in these aquifers 

rise at the beginning of the irrigation season and decline 

during the off-season. The magnitude of this fluctuation is 

generally 5 to 10 feet in the main part of the Klamath Project. 

Water levels in wells near Upper Klamath Lake fluctuate in 

concert with lake stage.

This study was intended to develop an understanding of 

the regional ground-water flow system in the upper Klamath 

Basin to help resource managers and basin residents develop 

a strategy for managing ground water. Developing a groundwater management strategy for the upper Klamath Basin will 

require consideration of general characteristics of groundwater flow and characteristics unique to the upper Klamath 

Basin. Generally, increases in the rate of pumping from 

a ground-water system will eventually be offset by either 

increased rates of recharge or (more likely) diminished rates 

of discharge. Mechanisms whereby ground-water recharge 

is increased by pumping are rare. In some circumstances, the 

lowering of hydraulic head caused by pumping could cause 

increased leakage from streams to the ground-water system. 

Conditions where this could occur in the upper Klamath Basin 

are rare. Pumping ground water near basin boundaries can 

cause the boundaries to shift, effectively capturing recharge 

from adjacent basins. However, only a fraction of the pumpage 

would be made up by flow from adjacent basins given likely 

pumping locations. Diminishment of discharge is the more 

likely consequence of ground-water extraction. Most of the 

decrease would be in ground-water discharge to streams, 

although reductions in discharge to phreatophytes (riparian or 

wetland vegetation with roots that extend to the water table) 

and in flows of ground water moving out of the basin in the 

subsurface could occur as well.

The timing and distribution of the effects of groundwater use are dictated to a large degree by the location of 

pumping. Pumping very near to discharge areas, such as 

springs, can diminish the flow of the springs relatively quickly. 

There have been several instances (with varying amounts of 

documentation) where ground-water pumping has affected 

spring discharge in the upper Klamath Basin. Springs affected 

by pumping in the past include those in Bonanza, elsewhere 

in the Lost River subbasin, and near Whisky Creek in the 

Sprague River subbasin.

Ground water is a major component of streamflow in 

the upper Klamath Basin, and, consequently, ground-water 

development has the potential to affect streamflow. Because 

the rate, spatial distribution, and variability of ground-water 

discharge in the upper Klamath Basin is now well understood, 

ground-water management strategies can be developed that 

minimize the effects of ground-water use.

Recently, a considerable effort has been made by various 

agencies, including the U.S. Geological Survey, the Oregon 

Water Resources Department, the California Department of 

Water Resources, and the Bureau of Reclamation, to monitor 

ground-water levels and ground-water discharge in the 

upper Klamath Basin. This information has been valuable in 

developing the present understanding of the regional groundwater system and its response to natural and human-caused 

stresses. Continued data collection will be important in the 

future to quantify the response of the ground-water system to 

stresses.

Acknowledgments

The authors gratefully acknowledge the support of the 

residents of the upper Klamath Basin, particularly the many 

hundreds of individuals who allowed access to property and 

wells for water-level measurements and monitoring over the 

course of several years. Our understanding of the groundwater hydrology of the upper Klamath Basin benefited 

tremendously from many hours of discussions with land 

owners and scientists working in the basin, who freely shared 

observations, insights, and valuable data. Particular thanks go 

to Noel Eaves and Bill Ehorn of the California Department of 

Water Resources; Jon Hicks, John Rasmussen, and Tom Perry 

of the Bureau of Reclamation; Jerry Grondin and Ned Gates 

of the Oregon Water Resources Department; Tim Mayer of 

the U.S. Fish and Wildlife Service; Mike Stansbury of Water 

and Energy Services (WESCORP); Steve Luxton of W&H 

Pacific; Toni Boyd and John Lund of the Oregon Institute of 

Technology Geo-Heat Center; and the staffs of the Klamath 

National Wildlife Refuges Complex and Lava Beds National 

Monument. Our understanding of the geology of the region 

Acknowledgments 65
benefited from discussions with Mike Cummings of Portland 

State University, Frank Hladky, Margi Jenks, and Ian Madin 

of the Oregon Department of Geology and Mineral Industries, 

and Dave Sherrod of the U.S. Geological Survey. Part of the 

Oregon Water Resources Department contribution to this 

project was funded through grant assistance from the Bureau 

of Reclamation Klamath Basin Area Office.

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Snyder, D.T., and Morace, J.L., 1997, Nitrogen and 

phosphorous loading from drained wetlands adjacent 

to Upper Klamath and Agency Lakes, Oregon: U.S. 

Geological Survey Water-Resources Investigations Report 

97-4059, 67p.

Stonestrom, D.A., Prudic, D.E., Laczniak, R.J., Akstin, K.C., 

Boyd, R.A., and Henkelman, K.K., 2003, estimates of 

deep percolation beneath native vegetation, irrigated fields, 

and the Amargosa-River channel, Amargosa Desert, Nye 

County, Nevada: U.S. Geological Survey Open File Report 

03-14, 83 p.

68 Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California
Theis, C.V., 1935, The relation between the lowering of 

the piezometric surface and the rate and duration of 

discharge of a well using ground-water storage: American 

Geophysical Union Transactions, 16th Annual Meeting, part 

2, p. 518-524.

U.S. Department of Agriculture, 2004, Statistics by state—

Oregon: http://www.nass.usda.gov/Statistics_by_State/

Oregon, accessed January 5, 2007.

U.S. Geological Survey, 1956, Surface water supply of 

the United States, 1954, Part 11, Pacific slope basins in 

California: U.S. Geological Survey Water-Supply Paper 

1345, 574 p.

U.S. Geological Survey, 1960a, Surface water supply of 

the United States, 1959, Part 11, Pacific slope basins in 

California: U.S. Geological Survey Water-Supply Paper 

1635, 748 p.

U.S. Geological Survey, 1960b, Compilation of records of 

surface waters of the United States through September 

1950. Part 11-A, Pacific slope basins in California, except 

Central Valley: U.S. Geological Survey Water-Supply Paper 

1315-B, p. 471-864.

U.S. Geological Survey, [various dates], Surface water supply 

of the United States, Pacific slope basins in California: U.S. 

Geological Survey Water-Supply Paper, various parts.

Vance, J.A., 1984, The lower Western Cascades Volcanic 

Group in northern California, in Nilsen, T.H. ed., Geology 

of the Upper Cretaceous Hornbrook Formation, Oregon 

and California: Society of Economic Paleontologists and 

Mineralogists, Pacific Section, Field Trip Guidebook v. 42, 

p. 195-196.

Veen, C.A., 1981, Gravity anomalies and their structural 

implications for southern Oregon Cascade Mountains and 

adjoining Basin and Range province: Corvallis, Oregon, 

Oregon State University, M.S. thesis, 86 p.

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map of the Weed Quadrangle: California Division of Mines 

and Geology Regional Geologic Map Series Map No. 4A 

(Geology), 15 p., scale 1:250,000, 4 sheets.

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eastern half of the Klamath Falls (AMS) quadrangle, Lake 

and Klamath counties, Oregon: U.S. Geological Survey 

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videography, Watershed Sciences, LLC, Corvallis, OR, 29 

p., plus appendices.

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Basin economy and the role of agriculture: in Braunworth, 

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allocation in the Klamath Reclamation Project: an 

assessment of natural resource, economic, social, and 

institutional issues with a focus on the upper Klamath 

Basin, Oregon State University Extension Service Special 

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powder River Basin, Montana. II. Aquifer test analysis: 

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Klamath NWR groundwater program-2002 groundwater 

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[PSC-P 58777], 9 p. plus figures and tables.

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County, Oregon: State of Oregon Water Resources 

Department Ground Water Open File Report 02-004, 35 p. 

plus 3 appendices.

References Cited 69
70 Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California

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Appendix A. Landsat Analysis 

Methods

The imagery classification was based on two levels of 

resolution: (1) a generalized nonirrigated level that consisted 

of four Anderson Level I/II classes: ice and snow, evergreen 

forest, water, and shrub lands that represented a combination 

of bare soil, rock, sagebrush and other nonirrigated vegetation 

(Anderson and others, 1976); and (2) irrigated lands clustered 

into five vegetative classes based on their spectral similarity 

and potential crop water needs. These classes were labeled 

alfalfa and irrigated grasses, small grains, onions-garlic, 

potatoes-corn, and strawberries. Although it would have been 

desirable, identification of individual crop types proved to be 

impossible because of the lack of unique spectral signatures 

(Paul Seevers, EROS Data Center, written commun., 2000). 

The use of three satellite images from different times during 

the growing season increased the probability that certain croptypes could be distinguished based on the development of their 

spectral signatures. To aid in the classification of the imagery, 

field work was conducted to map directly crop types in areas 

totaling about 17,000 acres. A variety of representative landcover types were observed, including native trees, pasture 

and most of the agricultural crops. Most data were collected 

in mid-July. Data on crop type and height, percentage of crop 

cover, sprinkler type, and other parameters also were collected.

The three images were processed in succession. The May 

21, 2000, scene (from Landsat 5) showed full canopy cover of 

the perennial crops such as alfalfa, irrigated grasses, and any 

winter wheat that may have been planted the previous fall. 

The timing of the scene put it before any annual row crops 

had enough growth to show a vegetative signature. Areas 

with vigorous growth in the May scene served to mask over 

the same areas in the August scene. This step reduced the 

amount of data in the August scene that required analysis. The 

irrigation district boundaries were used to segregate irrigated 

areas outside of the Klamath Project. The August 1 scene 

(from Landsat 7) revealed the full canopy of the annual row 

crops planted during the spring. The September 18 scene (also 

from Landsat 7) was used to show any crops that might have a 

vigorous vegetative signature beyond the harvest dates of the 

small grains.

A review was performed on the results of the final landcover classification by creating an error matrix to evaluate 

how well the classification of the imagery matched what was 

actually mapped on the ground. The review looked at how 

accurately the classification identified specific crop-types 

and how accurately the classification did with respect to all 

irrigated crop-classes. To do this, the new land-cover map 

created from the classified Landsat imagery was converted 

to a polygon dataset, with each polygon being 30 meters, the 

resolution of the original imagery. Each polygon contained a 

code for crop class determined by the classification process. 

The ground reference boundaries were then used to clip out 

the same areas in the classified land cover. The clipped landcover polygons were then evaluated by crop class against the 

ground reference. For example, if a ground reference area 

was identified as alfalfa, then the same area was compared in 

the land cover. The results of the review showed that largeacreage crops such as alfalfa had a correct classification ratio 

of about 64 percent. However, if all irrigated crop classes were 

included then the accuracy of identifying irrigated lands within 

that area increased to about 73 percent. For crops grown on 

smaller fields, the accuracy of the classification to identify 

specific crop class decreased to a range of 20 to 30 percent. If 

all irrigated lands were included then the accuracy increased to 

the 50 to 70 percent range. Sugar beet fields for example, were 

correctly classified 34 percent of the time, but if all irrigated 

lands for the same area were included then the accuracy 

increased to 62 percent. All mint and strawberry fields were 

located during the ground truth and were included in the final 

classification.

Appendix A. 71
72 Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California Table 6. Estimated ground-water discharge to principal stream reaches in the upper Klamath Basin, Oregon and California.

[Reach: River miles in Reach column are from Oregon Water Resources Department Klamath Drainage Basin Map, Map No. 14.6, 1971. Confidence level: Confidence levels represent a subjective assessment of the interval (plus or minus) that has a 95 percent probability of containing the true value. Confidence level categories are: 1, 10 percent; 2, 20 percent; 3, 30 percent; 4, 50 percent; 5, data insufficient to assess uncertainty. Subtotals rounded to two significant figures. Unless otherwise noted, values were derived by taking the average of estimated discharge in the fall (Sept, Oct, Nov). USGS synoptic measurement data from Leonard and Harris (1974). Abbreviations: BOR, Bureau of Reclamation; CDWR, California Department of Water Resources; Cr, Creek; ft3/s, cubic feet per second; Hwy, Highway; mi, mile; NA, 

not applicable; NPS, National Park Service; OWRD, Oregon Water Resources Department; R, River; Res, Reservoir; RM, river mile; RR, rail road; USFS, U.S. Forest Service; USGS, U.S. Geological Survey]

Number Stream name Reach

Estimated gain 

(+) or loss (-) 

(ft3/s)

Data source Period of record Methods Remarks Confidence level

1 South Fork 

Sprague River

Headwaters to above 

Brownsworth Cr (RM 15.2)

14 USFS gage 10/1992-

09/1997

Index regression to Chewaucan 

near Paisley, Oreg. (USGS site 10384000)

OWRD site 61420208 3

2 Brownsworth 

Creek

Entire drainage 5 USFS 

measurements (46)

12/1991-

04/1997

Miscellaneous measurement 

regression to Chewaucan near Paisley, Oreg. (USGS site 10384000)

OWRD site 21420206 3

3 Fritz and 

Deming Creeks

Entire drainage of both 

creeks

5 N/A N/A Regional regression 5

1

4 South Fork 

Sprague River

Brownsworth Cr (RM 

15.2) to picnic area (RM 10.2)

0 USFS 

measurements (34)

1/1992– 

3/1996

Miscellaneous measurement 

regression to Chewaucan near Paisley, Oreg. (USGS site 10384000). Mass balance.

OWRD site 21420201. Gains 

calculated from difference with upstream inflows.

3

Subtotal for South Fork Sprague River 24

5 North Fork 

Sprague River

Headwaters to above 

Sandhill Crossing (RM 23.5)

16 USFS gage 10/1992–

9/1997

Index regression to Chewaucan 

near Paisley, Oreg. (USGS site 10384000)

OWRD site 61420206 3

6 North Fork 

Sprague River

Sandhill Crossing to 

The Elbow (RM 23.5 to RM 12.2)

43 USFS 

measurements (46)

01/1992– 

05/1997

Miscellaneous measurement 

regression to Chewaucan near Paisley (USGS site 10384000). Mass balance.

OWRD site 21420202. Gains 

calculated from difference with upstream inflows.

2

7 Meryl Creek Headwaters to 

approximately 1.5 mi above mouth

13 USGS/OWRD 

measurements (5)

09/1915, 

09/1954, 10/1970, 09/1983, 11/2000

Average Majority of measurements 

approximately 1.5 mi from mouth.

4

8 Fivemile 

Creek

Headwaters to 

approximately 4.0 mi above mouth

20 USGS/OWRD 

measurements (280)

08/1917– 

09/1973

Miscellaneous measurement 

regression to Williamson R below Sprague R near Chiloquin, Oreg. (USGS site 11502500). 

Measurements at USGS site 

11497000. Used data as miscellaneous measurement site due to large amounts of missing data. 

1
Table 6

73

Table 6. Estimated ground-water discharge to principal stream reaches in the upper Klamath Basin, Oregon and California.—Continued[Reach: River miles in Reach column are from Oregon Water Resources Department Klamath Drainage Basin Map, Map No. 14.6, 1971. Confidence level: Confidence levels represent a subjective assessment of the interval (plus or minus) that has a 95 percent probability of containing the true value. Confidence level categories are: 1, 10 percent; 2, 20 percent; 3, 30 percent; 4, 50 percent; 5, data insufficient to assess uncertainty. Subtotals rounded to two significant figures. Unless otherwise noted, values were derived by taking the average of estimated discharge in the fall (Sept, Oct, Nov). USGS synoptic measurement data from Leonard and Harris (1974). Abbreviations: BOR, Bureau of Reclamation; CDWR, California Department of Water Resources; Cr, Creek; ft3/s, cubic feet per second; Hwy, Highway; mi, mile; NA, 

not applicable; NPS, National Park Service; OWRD, Oregon Water Resources Department; R, River; Res, Reservoir; RM, river mile; RR, rail road; USFS, U.S. Forest Service; USGS, U.S. Geological Survey]

Number Stream name Reach

Estimated gain 

(+) or loss (-) 

(ft3/s)

Data source Period of record Methods Remarks Confidence level

19 North Fork 

Sprague River

The Elbow (RM 12.2) 

to RM 1.5

0 OWRD synoptic 

measurement

11/2000 Synoptic measurement No gains other than tributary 

inflows.

3

Subtotal for North Fork Sprague River 92

10 Upper Sprague 

River

South Fork Sprague 

at Picnic Area (RM 10.2) to Sprague at Cinder Pit (RM 77.5)

26 OWRD/USGS 

synoptic measurements (2)

11/2000, 

10/1970

Average Good agreement between 

seepage measurements. Discharge recorded at Beatty gage during synoptic measurements was close to long term average.

3

11 Upper Sprague 

River

Cinder Pit (RM 77.5) 

to OWRD gage at Beatty Gap (RM 75)

26 OWRD/USGS 

synoptic measurements (2)

11/2000, 

10/1970

Average Large difference between 

synoptic measurements.

4

Subtotal for upper Sprague River 52

112 Lower Sprague 

River

OWRD gage at Beatty 

Gap (RM 75) to below old RR crossing (RM 74.2)

34 OWRD/USGS 

synoptic measurements (3)

10/1970, 

11/2000, 10/2002

Average Estimate includes gains from 

Medicine Springs (14 ft3/s 

from seven measurements).

3

113 Spring Creek Headwater to mouth 

(Sprague RM 73.2). Note: Spring Creek is too short to show on figures; enters Sprague near Brown Creek.

18 OWRD synoptic 

measurements (2)

11/2000, 

10/2002

Average Good agreement between 

synoptic measurements. 

4

14 Brown Creek Headwater to 1 mi 

above confluence (Sprague RM 73)

3 OWRD synoptic 

measurements (2)

11/2000, 

10/2002

Average Good agreement between 

synoptic measurements. 

4
74 Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California Table 6. Estimated ground-water discharge to principal stream reaches in the upper Klamath Basin, Oregon and California.—Continued

[Reach: River miles in Reach column are from Oregon Water Resources Department Klamath Drainage Basin Map, Map No. 14.6, 1971. Confidence level: Confidence levels represent a subjective assessment of the interval (plus or minus) that has a 95 percent probability of containing the true value. Confidence level categories are: 1, 10 percent; 2, 20 percent; 3, 30 percent; 4, 50 percent; 5, data insufficient to assess uncertainty. Subtotals rounded to two significant figures. Unless otherwise noted, values were derived by taking the average of estimated discharge in the fall (Sept, Oct, Nov). USGS synoptic measurement data from Leonard and Harris (1974). Abbreviations: BOR, Bureau of Reclamation; CDWR, California Department of Water Resources; Cr, Creek; ft3/s, cubic feet per second; Hwy, Highway; mi, mile; NA, 

not applicable; NPS, National Park Service; OWRD, Oregon Water Resources Department; R, River; Res, Reservoir; RM, river mile; RR, rail road; USFS, U.S. Forest Service; USGS, U.S. Geological Survey]

Number Stream name Reach

Estimated gain 

(+) or loss (-) 

(ft3/s)

Data source Period of record Methods Remarks Confidence level

15 Sprague River Near old RR crossing 

(RM 74.2) to Watchdog Butte (RM 49)

7 OWRD/USGS 

synoptic measurements (2)

11/2000, 

10/1970

Average Gains within measurement 

error. However, some springs in the vicinity RM 69 and 70. Springs measured 4 ft3/s in 10/2002. 

Synoptic measurements made when flows recorded at USGS gage near Chiloquin were similar to long term average.

4

16 Whisky Creek Headwaters to 

approximately 1.0 mi above mouth

13 OWRD/USGS 

synoptic measurements (3)

10/1970, 

11/2000, 10/2002

Average 1970 measurement about 10 

ft3/s larger than others.

4

117 Sprague River Watchdog Butte (RM 

49) to below Trout Cr confluence (RM 37)

0 OWRD 11/1/2000 Synoptic measurement Synoptic measurements made 

when flows recorded at USGS gage near Chiloquin were similar to long-term average fall flow.

3

118 Sprague River Trout Cr confluence 

(RM 37) to bridge near Lone Pine (RM 33)

0 OWRD synoptic 

measurements (2)

11/2000, 

10/2002

Average Synoptic measurements on 

10/1970 demonstrate gain of 30 ft3/s. Recent results 

do not concur with this finding.

4

119 Sprague River Bridge near Lone Pine 

(RM 33) to above Wolff Ranch (RM 28.5)

4 OWRD/USGS 

synoptic measurements (3)

10/1970, 

11/2000, 10/2002

Average Gains within measurement 

error.

3

20 Sprague River above Wolff Ranch 

(RM 28.5) to below Kamkaun Springs (RM 23.2)

50 OWRD synoptic 

measurements

11/2000 Synoptic measurement Good agreement with average 

of 26 direct measurements 

on Kamkaun/McReady springs made from 04/1920 to 09/1973

2
Table 6

75

Table 6. Estimated ground-water discharge to principal stream reaches in the upper Klamath Basin, Oregon and California.—Continued[Reach: River miles in Reach column are from Oregon Water Resources Department Klamath Drainage Basin Map, Map No. 14.6, 1971. Confidence level: Confidence levels represent a subjective assessment of the interval (plus or minus) that has a 95 percent probability of containing the true value. Confidence level categories are: 1, 10 percent; 2, 20 percent; 3, 30 percent; 4, 50 percent; 5, data insufficient to assess uncertainty. Subtotals rounded to two significant figures. Unless otherwise noted, values were derived by taking the average of estimated discharge in the fall (Sept, Oct, Nov). USGS synoptic measurement data from Leonard and Harris (1974). Abbreviations: BOR, Bureau of Reclamation; CDWR, California Department of Water Resources; Cr, Creek; ft3/s, cubic feet per second; Hwy, Highway; mi, mile; NA, 

not applicable; NPS, National Park Service; OWRD, Oregon Water Resources Department; R, River; Res, Reservoir; RM, river mile; RR, rail road; USFS, U.S. Forest Service; USGS, U.S. Geological Survey]

Number Stream name Reach

Estimated gain 

(+) or loss (-) 

(ft3/s)

Data source Period of record Methods Remarks Confidence level

21 Sprague River Kamkaun Springs (RM 

23.2) to Hwy Bridge near Braymill (RM 10.1)

19 OWRD synoptic 

measurement

11/2000 Synoptic measurement Gains probably near 

Whitehorse Spring

3

122 Sprague River Braymill (RM 10.1) to 

Chiloquin (RM 5.2)

0 OWRD synoptic 

measurement

11/2000 Synoptic measurement 3

Subtotal for lower Sprague River 150

123 Long Creek Headwaters to T31S, 

R12E, S5

9 USFS gage 10/1992–

09/1997

Index regression to Eagle Cr 

above Skull Cr, near New Bridge, Oreg. (USGS Site 13288200)

OWRD site 61420205 1

24 Long Creek T31S, R12E, S5 to 

mouth (Sycan Marsh)

7 N/A N/A Regional regression Ungaged drainage area below 

USFS gage (OWRD site 61420205)

5

25 Sycan River Headwaters to Sycan 

Marsh (RM 46.5)

8 USFS gage 10/1992–

09/1997

Index regression to Deep Cr 

above Adel, Oreg. (USGS Site 10371500).

OWRD site 61420209 2

Subtotal for upper Sycan River 24

126 Sycan Marsh Sycan Marsh -10 to -20 USFS gages 10/1992–

09/1997

Mass balance and index regression 

of USFS gage below Sycan Marsh to Chewaucan R near Paisley (USGS Site 10384000). 

OWRD site 61420210. Gains 

calculated from mass balance with upstream estimates during the fall.

5

Subtotal for Sycan Marsh -10 to -20

127 Sycan River Sycan Marsh Outlet 

(RM 35) to RM 30 (above Torrent Spring)

0 OWRD synoptic 

measurement

08/2000 Synoptic measurement Overall gains from synoptic 

measurements below Sycan Marsh in 08/2000 is similar to average difference in fall flows from gages at OWRD site 61420210 to USGS Site 11499100.

3
76 Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California Table 6. Estimated ground-water discharge to principal stream reaches in the upper Klamath Basin, Oregon and California.—Continued

[Reach: River miles in Reach column are from Oregon Water Resources Department Klamath Drainage Basin Map, Map No. 14.6, 1971. Confidence level: Confidence levels represent a subjective assessment of the interval (plus or minus) that has a 95 percent probability of containing the true value. Confidence level categories are: 1, 10 percent; 2, 20 percent; 3, 30 percent; 4, 50 percent; 5, data insufficient to assess uncertainty. Subtotals rounded to two significant figures. Unless otherwise noted, values were derived by taking the average of estimated discharge in the fall (Sept, Oct, Nov). USGS synoptic measurement data from Leonard and Harris (1974). Abbreviations: BOR, Bureau of Reclamation; CDWR, California Department of Water Resources; Cr, Creek; ft3/s, cubic feet per second; Hwy, Highway; mi, mile; NA, 

not applicable; NPS, National Park Service; OWRD, Oregon Water Resources Department; R, River; Res, Reservoir; RM, river mile; RR, rail road; USFS, U.S. Forest Service; USGS, U.S. Geological Survey]

Number Stream name Reach

Estimated gain 

(+) or loss (-) 

(ft3/s)

Data source Period of record Methods Remarks Confidence level

28 Torrent Spring Above and below 

Torrent Spring on Sycan R (RM 30 to RM 24)

12 OWRD/USFS 

synoptic measurements (5)

10/1997, 

10/1998, 08/1999, 10/1999, 08/2000

Average Synoptic measurement in 

08/2000, plus additional synoptic measurements taken at RM 35 and RM 24. Overall gains from synoptic measurements below Sycan Marsh in 08/2000 is similar to average difference in fall flows from gages.

3

129 Sycan River Below Torrent 

Springs (RM 24) to confluence with Blue Cr (RM 11)

0 OWRD synoptic 

measurement

08/2000 Synoptic measurement Overall gains from synoptic 

measurements below Sycan Marsh in 08/2000 is similar to average difference in fall flows from gages at OWRD site 61420210 to USGS Site 11499100.

3

130 Brown Creek 1/4 mi below spring 4 OWRD synoptic 

measurement

08/2000 Synoptic measurement Overall gains from synoptic 

measurements below Sycan Marsh in 08/2000 is similar to average difference in fall flows from gages at OWRD site 61420210 to USGS Site 11499100.

3

31 Sycan River Blue Cr confluence 

(RM 11) to OWRD gage (RM 3)

5 OWRD synoptic 

measurement

08/2000 Synoptic measurement Overall gains from synoptic 

measurements below Sycan Marsh in 08/2000 is similar to average difference in fall flows from gages at OWRD site 61420210 to USGS Site 11499100.

3

Subtotal for lower Sycan River 21
Table 6

77

Table 6. Estimated ground-water discharge to principal stream reaches in the upper Klamath Basin, Oregon and California.—Continued[Reach: River miles in Reach column are from Oregon Water Resources Department Klamath Drainage Basin Map, Map No. 14.6, 1971. Confidence level: Confidence levels represent a subjective assessment of the interval (plus or minus) that has a 95 percent probability of containing the true value. Confidence level categories are: 1, 10 percent; 2, 20 percent; 3, 30 percent; 4, 50 percent; 5, data insufficient to assess uncertainty. Subtotals rounded to two significant figures. Unless otherwise noted, values were derived by taking the average of estimated discharge in the fall (Sept, Oct, Nov). USGS synoptic measurement data from Leonard and Harris (1974). Abbreviations: BOR, Bureau of Reclamation; CDWR, California Department of Water Resources; Cr, Creek; ft3/s, cubic feet per second; Hwy, Highway; mi, mile; NA, 

not applicable; NPS, National Park Service; OWRD, Oregon Water Resources Department; R, River; Res, Reservoir; RM, river mile; RR, rail road; USFS, U.S. Forest Service; USGS, U.S. Geological Survey]

Number Stream name Reach

Estimated gain 

(+) or loss (-) 

(ft3/s)

Data source Period of record Methods Remarks Confidence level

32 Williamson 

River

Head of River Springs 

(RM 86)

8 OWRD synoptic 

measurement

11/2002 Synoptic measurement Dry conditions. Synoptic 

measurements made when OWRD gage below Sheep Cr (USGS Site 11491400) at 85 percent of average fall flows.

2

33 Williamson 

River

Head of River (RM 86) 

to downstream side of reservoir below Bull Pasture (RM 81)

8 OWRD synoptic 

measurement

11/2002 Synoptic measurement Dry conditions. Synoptic 

measurements made when OWRD gage below Sheep Cr (USGS Site 11491400) at 85 percent of average fall flows.

2

34 Williamson 

River

Reservoir (RM 81) 

to above Wickiup Spring (RM 79.8)

14 OWRD synoptic 

measurement

11/2002 Synoptic measurement Dry conditions. Synoptic 

measurements made when OWRD gage below Sheep Cr (USGS Site 11491400) at 85 percent of average fall flows.

2

35 Wickiup 

Spring

RM 79.8 24 OWRD synoptic 

measurement

11/2002 Synoptic measurement Dry conditions. Synoptic 

measurements made when OWRD gage below Sheep Cr (USGS Site 11491400) at 85 percent of average fall flows.

2

136 Williamson 

River

Below Wickiup Spring 

(RM 79.8) to OWRD gage below Sheep Cr (RM 67.7)

0 OWRD synoptic 

measurement

11/2002 Synoptic measurement Dry conditions. Synoptic 

measurements made when OWRD gage below Sheep Cr (USGS Site 11491400) at 85 percent of average fall flows.

2

37 Jackson 

Creek

Headwaters to road 

crossing

6 USFS 

measurements (68)

11/1991-

04/1997

Miscellaneous measurement 

regression to Chewaucan near Paisley, Oreg. (USGS Site 10384000).

OWRD site 21420110 4
78 Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California Table 6. Estimated ground-water discharge to principal stream reaches in the upper Klamath Basin, Oregon and California.—Continued

[Reach: River miles in Reach column are from Oregon Water Resources Department Klamath Drainage Basin Map, Map No. 14.6, 1971. Confidence level: Confidence levels represent a subjective assessment of the interval (plus or minus) that has a 95 percent probability of containing the true value. Confidence level categories are: 1, 10 percent; 2, 20 percent; 3, 30 percent; 4, 50 percent; 5, data insufficient to assess uncertainty. Subtotals rounded to two significant figures. Unless otherwise noted, values were derived by taking the average of estimated discharge in the fall (Sept, Oct, Nov). USGS synoptic measurement data from Leonard and Harris (1974). Abbreviations: BOR, Bureau of Reclamation; CDWR, California Department of Water Resources; Cr, Creek; ft3/s, cubic feet per second; Hwy, Highway; mi, mile; NA, 

not applicable; NPS, National Park Service; OWRD, Oregon Water Resources Department; R, River; Res, Reservoir; RM, river mile; RR, rail road; USFS, U.S. Forest Service; USGS, U.S. Geological Survey]

Number Stream name Reach

Estimated gain 

(+) or loss (-) 

(ft3/s)

Data source Period of record Methods Remarks Confidence level

38 Jack Creek Headwaters to Silver 

Lake Road

2 OWRD synoptic 

measurement

03/2000 Synoptic measurement Wet conditions. Synoptic 

measurements made when OWRD gage below Sheep Cr (USGS Site 11491400) at 120 percent of average fall flows.

4

39 Williamson 

River

OWRD gage below 

Sheep Cr (RM 67.7) to above Cholo Ditch (RM 58.3)

18 OWRD synoptic 

measurement

03/2000 Synoptic measurement Wet conditions. Synoptic 

measurements made when OWRD gage below Sheep Cr (USGS Site 11491400) at 120 percent of average fall flows.

4

Subtotal for upper Williamson River 80

40 Klamath 

Marsh

Cholo Ditch (RM 58.3) 

to Kirks Reef (RM 27)

50 USFWS 

marsh stage measurements and OWRD, USGS, USFWS gage data

1971–2000 Mass balance. Annual Average Mass balance used gaged 

inflows and outflows, precipitation recorded at Chemult, and marsh evapotranspiration rates from USFWS rates coupled with ungaged tributary flow estimates

5

Subtotal for Klamath Marsh 50

41 Big Springs 

Creek

Headwaters to 

confluence with Lenz Cr

34 OWRD 

measurements (33)

10/1916–

09/1987

Average Synoptic measurements 

demonstrate some gains to creek below confluence with Lenz Cr and above mouth

4

42 Miller Creek Headwaters to National 

Forest Boundary (RM 8.3)

8 USFS gage 10/1992–

09/1997

Index regression to Eagle Cr 

above Skull Cr, near New Bridge, Oreg. (USGS Site 13288200)

OWRD site 61420102 3
Table 6

79

Table 6. Estimated ground-water discharge to principal stream reaches in the upper Klamath Basin, Oregon and California.—Continued[Reach: River miles in Reach column are from Oregon Water Resources Department Klamath Drainage Basin Map, Map No. 14.6, 1971. Confidence level: Confidence levels represent a subjective assessment of the interval (plus or minus) that has a 95 percent probability of containing the true value. Confidence level categories are: 1, 10 percent; 2, 20 percent; 3, 30 percent; 4, 50 percent; 5, data insufficient to assess uncertainty. Subtotals rounded to two significant figures. Unless otherwise noted, values were derived by taking the average of estimated discharge in the fall (Sept, Oct, Nov). USGS synoptic measurement data from Leonard and Harris (1974). Abbreviations: BOR, Bureau of Reclamation; CDWR, California Department of Water Resources; Cr, Creek; ft3/s, cubic feet per second; Hwy, Highway; mi, mile; NA, 

not applicable; NPS, National Park Service; OWRD, Oregon Water Resources Department; R, River; Res, Reservoir; RM, river mile; RR, rail road; USFS, U.S. Forest Service; USGS, U.S. Geological Survey]

Number Stream name Reach

Estimated gain 

(+) or loss (-) 

(ft3/s)

Data source Period of record Methods Remarks Confidence level

43 Sink Creek Headwaters to RM 6.2 4 USFS gage 10/1995–

09/1997

Index regression to Eagle Cr 

above Skull Cr, near New Bridge, Oreg. (USGS Site 13288200)

OWRD site 61420104 2

44 Scott Creek Headwaters to above 

Highway 232 (RM 4.6)

9 OWRD(52) and 

USFS(50) measurements

06/1929–

05/1993 (OWRD) and 08/1991–05/1997 (USFS)

Miscellaneous measurement 

regression to Deschutes River below Snow Cr, near Lapine, Oreg. (USGS Site 14050000)

OWRD site 21420107 3

45 Sand Creek Headwaters to above 

Highway 232 (RM 5.8)

23 USFS gage 10/1992–

09/1997

Index regression to Deschutes 

River below Snow Cr, near Lapine, Oreg. (USGS Site 14050000)

OWRD site 61420103 3

Subtotal for Klamath Marsh tributaries 78

146 Williamson 

River

Kirks Reef (RM 27) 

to base of falls near Calimus (RM 22.2)

0 OWRD synoptic 

measurement

10/2002 Synoptic measurement 4

47 Williamson 

River

Calimus (RM 22.2) to 

old USGS Station 11494000 (RM 19.7)

22 OWRD 

measurements (16)

10/1955–

09/1973

Average Average of difference in 

concurrent flows recorded at Kirk (USGS Site 11493500) and below Road 9730 (USGS Site 11494000). From synoptic measurements on 10/2002, gains appear to occur below Calimus.

3

148 Larkin Creek At Williamson 

confluence (RM 19.2)

10 OWRD 

measurements (27)

10/1923–

11/1985

Average OWRD site 21420105 3

149 Larkin Springs At Williamson 

confluence (RM 17.5)

10 OWRD synoptic 

measurement

10/2002 Synoptic measurement 4
80 Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California Table 6. Estimated ground-water discharge to principal stream reaches in the upper Klamath Basin, Oregon and California.—Continued

[Reach: River miles in Reach column are from Oregon Water Resources Department Klamath Drainage Basin Map, Map No. 14.6, 1971. Confidence level: Confidence levels represent a subjective assessment of the interval (plus or minus) that has a 95 percent probability of containing the true value. Confidence level categories are: 1, 10 percent; 2, 20 percent; 3, 30 percent; 4, 50 percent; 5, data insufficient to assess uncertainty. Subtotals rounded to two significant figures. Unless otherwise noted, values were derived by taking the average of estimated discharge in the fall (Sept, Oct, Nov). USGS synoptic measurement data from Leonard and Harris (1974). Abbreviations: BOR, Bureau of Reclamation; CDWR, California Department of Water Resources; Cr, Creek; ft3/s, cubic feet per second; Hwy, Highway; mi, mile; NA, 

not applicable; NPS, National Park Service; OWRD, Oregon Water Resources Department; R, River; Res, Reservoir; RM, river mile; RR, rail road; USFS, U.S. Forest Service; USGS, U.S. Geological Survey]

Number Stream name Reach

Estimated gain 

(+) or loss (-) 

(ft3/s)

Data source Period of record Methods Remarks Confidence level

50 Williamson 

River

USGS gage 

(11494000) (RM 19.7) to Larkin Springs confluence (RM 17.5)

6 OWRD synoptic 

measurement

10/2002 Synoptic measurement 4

51 Spring Creek Just above Williamson 

confluence at RM 16.5

300 OWRD 

measurements (39)

09/1908–

09/1993

Average Small year to year variability 1

Subtotal for lower Williamson River 350

52 Wood River Headwater springs to 

Dixon Road (RM 16.2)

250 OWRD 

measurements (68)

11/1925–

09/1989

Index regression to Fall River 

near Lapine, Oreg. (USGS Site 14057500)

OWRD site 21420395 1

53 Annie Creek Headwaters to National 

Park Boundary (RM 5.7)

56 USFS gage 10/1992–

09/1997

Index regression to Deschutes 

River below Snow Cr, near Lapine, Oreg. (USGS Site 14050000)

OWRD site 61420301 2

54 Sun Creek Headwaters to National 

Park Boundary (RM 5.0)

13 NPS 

measurements (99)

07/1989–

09/1997

Miscellaneous measurement 

regression to Deschutes River below Snow Cr, near Lapine, Oreg. (USGS Site 14050000)

OWRD site 21420310 2

55 Fort Creek Headwaters to near 

Hwy 62 (RM 1.0)

84 OWRD 

measurements (22)

11/1954–

03/1981

Index regression to Fall River 

near Lapine, Oreg. (USGS Site 14057500)

OWRD site 21420398 1

56 Crooked Creek Headwaters to above 

Tecumseh Springs (RM 5.4) near Hwy 62

43 OWRD 

measurements (16)

11/1983–

09/1987

Average of all measurements 2

157 Tecumseh 

Springs

Tecumseh Springs 27 USGS/OWRD 

measurements (7)

08/1907–

10/1909

Average of all measurements 3

58 Agency Creek Headwaters to mouth 21 USGS/OWRD 

measurements (5)

04/1924–

08/1954

Average of all measurements 3

Subtotal for Wood River and tributaries 490
Table 6

81

Table 6. Estimated ground-water discharge to principal stream reaches in the upper Klamath Basin, Oregon and California.—Continued[Reach: River miles in Reach column are from Oregon Water Resources Department Klamath Drainage Basin Map, Map No. 14.6, 1971. Confidence level: Confidence levels represent a subjective assessment of the interval (plus or minus) that has a 95 percent probability of containing the true value. Confidence level categories are: 1, 10 percent; 2, 20 percent; 3, 30 percent; 4, 50 percent; 5, data insufficient to assess uncertainty. Subtotals rounded to two significant figures. Unless otherwise noted, values were derived by taking the average of estimated discharge in the fall (Sept, Oct, Nov). USGS synoptic measurement data from Leonard and Harris (1974). Abbreviations: BOR, Bureau of Reclamation; CDWR, California Department of Water Resources; Cr, Creek; ft3/s, cubic feet per second; Hwy, Highway; mi, mile; NA, 

not applicable; NPS, National Park Service; OWRD, Oregon Water Resources Department; R, River; Res, Reservoir; RM, river mile; RR, rail road; USFS, U.S. Forest Service; USGS, U.S. Geological Survey]

Number Stream name Reach

Estimated gain 

(+) or loss (-) 

(ft3/s)

Data source Period of record Methods Remarks Confidence level

59 Sevenmile 

Creek

Headwaters to RM 17 18 USFS gage 10/1992–

09/1997

Index regression to North Umpqua 

River above Copeland Cr near Toketee Falls, Oreg. (USGS Site 14316500)

OWRD site 61420303 2

160 Crane Creek Headwaters to 

Sevenmile Road

11 USGS 

measurements (3)

05/1905–

08/1911

Average of all measurements 4

161 Mares Egg 

Spring

Headwaters to mouth 12 OWRD 

measurement (1)

10/1954 Four measurements averaged 

2.4 ft3/s during summer of 

1992 and 1994

4

62 Sevenmile 

Creek

RM 17 to Sevenmile 

Road

60 OWRD 

measurements (9)

10/1908–

10/1959

Average Unknown upstream diversions. 

OWRD Site 21420393

2

63 Cherry Creek Headwaters to West 

Side Road Crossing

12 USFS gage 10/1992–

09/1997

Index regression to Rogue R above 

Prospect, Oreg. (USGS Site 14328000)

OWRD site 61420302 and site 

21420397

2

64 Fourmile 

Creek

Headwaters to West 

Side Road Crossing

2 USGS gage 10/1964–

09/1967

Index regression to Deer Cr above 

Crane Prairie Res, near La Pine, Oreg. (USGS Site 14052000)

USGS Site 11505600, 

regulated at Fourmile Lake

4

Subtotal for other upper Klamath Lake 

tributaries

 120

65 Upper Klamath 

Lake

Upper Klamath 

Lake

350 USGS gages 10/1964–

09/1967

Mass balance. Annual average 

(rounded).

Published water balanced 

study from Hubbard (1970). Analysis used measured inflows, outflows, lake elevations, and evaporation estimates. Agrees with other estimates (Cooper, 2004)

3

Subtotal for upper Klamath Lake 350

66 Clear Lake Drainage to Clear Lake 

Reservoir Dam (RM 78)

40 USGS gage, 

BOR data

10/1904–

09/1951

Average 10/1904–05/1909 USGS gage, 

06/1909–09/1951 (Bureau of Reclamation, 1954)

4
82 Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California Table 6. Estimated ground-water discharge to principal stream reaches in the upper Klamath Basin, Oregon and California.—Continued

[Reach: River miles in Reach column are from Oregon Water Resources Department Klamath Drainage Basin Map, Map No. 14.6, 1971. Confidence level: Confidence levels represent a subjective assessment of the interval (plus or minus) that has a 95 percent probability of containing the true value. Confidence level categories are: 1, 10 percent; 2, 20 percent; 3, 30 percent; 4, 50 percent; 5, data insufficient to assess uncertainty. Subtotals rounded to two significant figures. Unless otherwise noted, values were derived by taking the average of estimated discharge in the fall (Sept, Oct, Nov). USGS synoptic measurement data from Leonard and Harris (1974). Abbreviations: BOR, Bureau of Reclamation; CDWR, California Department of Water Resources; Cr, Creek; ft3/s, cubic feet per second; Hwy, Highway; mi, mile; NA, 

not applicable; NPS, National Park Service; OWRD, Oregon Water Resources Department; R, River; Res, Reservoir; RM, river mile; RR, rail road; USFS, U.S. Forest Service; USGS, U.S. Geological Survey]

Number Stream name Reach

Estimated gain 

(+) or loss (-) 

(ft3/s)

Data source Period of record Methods Remarks Confidence level

67 Lost River Clear Lake Reservoir 

(RM 78) to Malone Dam (64.5)

2 BOR data 08/1987–

08/2002

Mass balance. Only November 

average used due to missingdata in other months.

Discharge in river and canals 

below Malone Dam minus Clear Lake mean monthly releases. Gains within uncertainty of estimate.

4

68 Gerber 

Reservoir

Drainage to Gerber 

Reservoir

10 USGS gage, 

BOR data

10/1904–

09/1951

Average Flows at Gerber reported by 

Bureau of Reclamation (1954)

4

69 Lost River Malone Dam (RM 

64.5) to Gift Road (RM 58)

11 OWRD synoptic 

measurement

12/1997 Synoptic measurement 4

70 Lost River Gift Road (RM 58) to 

Keller Bridge (RM 50.3)

16 OWRD synoptic 

measurement

12/1997 Synoptic measurement 4

71 Lost River Keller Bridge (RM 

50.3) to east Bonanza (RM 45.1)

9 OWRD synoptic 

measurement

12/1997 Synoptic measurement Synoptic overall gains (73 

ft3/s) from Keller Bridge 

to Harpold Dam is close to the average (82 ft3/s) of 13 

measurements taken from 11/1925–12/2001

3

72 Lost River East Bonanza (RM 

45.1) to Harpold Bridge (RM 43.9)

61 OWRD synoptic 

measurement

12/1997 Synoptic measurement Synoptic overall gains (73 

ft3/s) from Keller Bridge 

to Harpold Dam is close to the average (82 ft3/s) of 13 

measurements taken from 11/1925–12/2001

3

73 Lost River Harpold Bridge (RM 

43.9) to Harpold Dam (RM 40.8)

3 OWRD synoptic 

measurement

12/1997 Synoptic measurement Synoptic overall gains (73 

ft3/s) from Keller Bridge 

to Harpold Dam is close to the average (82 ft3/s) of 13 

measurements taken from 11/1925–12/2001

3

74 Lost River Harpold Dam (RM 

40.8) to Kirsh Bridge (RM 34.8)

10 OWRD synoptic 

measurement

12/1997 Synoptic measurement 4
Table 6

83

Table 6. Estimated ground-water discharge to principal stream reaches in the upper Klamath Basin, Oregon and California.—Continued[Reach: River miles in Reach column are from Oregon Water Resources Department Klamath Drainage Basin Map, Map No. 14.6, 1971. Confidence level: Confidence levels represent a subjective assessment of the interval (plus or minus) that has a 95 percent probability of containing the true value. Confidence level categories are: 1, 10 percent; 2, 20 percent; 3, 30 percent; 4, 50 percent; 5, data insufficient to assess uncertainty. Subtotals rounded to two significant figures. Unless otherwise noted, values were derived by taking the average of estimated discharge in the fall (Sept, Oct, Nov). USGS synoptic measurement data from Leonard and Harris (1974). Abbreviations: BOR, Bureau of Reclamation; CDWR, California Department of Water Resources; Cr, Creek; ft3/s, cubic feet per second; Hwy, Highway; mi, mile; NA, 

not applicable; NPS, National Park Service; OWRD, Oregon Water Resources Department; R, River; Res, Reservoir; RM, river mile; RR, rail road; USFS, U.S. Forest Service; USGS, U.S. Geological Survey]

Number Stream name Reach

Estimated gain 

(+) or loss (-) 

(ft3/s)

Data source Period of record Methods Remarks Confidence level

75 Lost River Kirsh Bridge (RM 

34.8) to Stevenson Park (RM 30.5)

29 OWRD synoptic 

measurement

12/1997 Synoptic measurement 4

76 Miller Creek Gerber Reservoir to 

mouth

4 OWRD 

measurement and BOR reservoir outflow data

12/1997 Mass balance from measurement 

and reservoir release data.

4

Subtotal for Lost River 200

77 Williow Creek Measured at bridge 

crossing about 3 mi from headwater springs

5.8 USGS 

measurements (4)

12/1954–

3/1955

Average Wood, 1960 4

78 Cottonwood 

Creek

Combined 

measurements of headwaterssprings

10 USGS 

measurements (4)

12/1954–

5/1955

Average Wood, 1960 4

79 Sheepy Creek Measured at road 

crossing (48N/1E35) about 1 mi north of headwater springs

16 USGS 

measurements (5)

11/1954–

5/1955

Average Wood, 1960 4

80 Hot Creek Measured at outlet of 

empty reservoir 47N/1E-3 about 0.5 mi from headwater springs

3.4 CDWR and 

USGS measurements

12/1954 

(stream)6/1954 (wells)

Flow of spring-fed stream with 

probable contributions from flowing artesian wells subtracted

Wood, 1960 4

Subtotal for lower Klamath Lake 35
84 Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California Table 6. Estimated ground-water discharge to principal stream reaches in the upper Klamath Basin, Oregon and California.—Continued

[Reach: River miles in Reach column are from Oregon Water Resources Department Klamath Drainage Basin Map, Map No. 14.6, 1971. Confidence level: Confidence levels represent a subjective assessment of the interval (plus or minus) that has a 95 percent probability of containing the true value. Confidence level categories are: 1, 10 percent; 2, 20 percent; 3, 30 percent; 4, 50 percent; 5, data insufficient to assess uncertainty. Subtotals rounded to two significant figures. Unless otherwise noted, values were derived by taking the average of estimated discharge in the fall (Sept, Oct, Nov). USGS synoptic measurement data from Leonard and Harris (1974). Abbreviations: BOR, Bureau of Reclamation; CDWR, California Department of Water Resources; Cr, Creek; ft3/s, cubic feet per second; Hwy, Highway; mi, mile; NA, 

not applicable; NPS, National Park Service; OWRD, Oregon Water Resources Department; R, River; Res, Reservoir; RM, river mile; RR, rail road; USFS, U.S. Forest Service; USGS, U.S. Geological Survey]

Number Stream name Reach

Estimated gain 

(+) or loss (-) 

(ft3/s)

Data source Period of record Methods Remarks Confidence level

81 Klamath 

River

Keno Dam (RM 230.5) 

to below JC Boyle powerplant (RM 218.1)

190 USGS gage and 

Pacific Corp. Reservoir data

10/1967–

10/1987, 10/1989–09/2001

Average (rounded). Mass balance. 

Derived from monthly mean discharge and reservoir content data. Excludes gains from Spencer Cr.

USGS gages: (11509500) 

Klamath River at Keno, Oreg. and (11510700) Klamath River below JC Boyle powerplant near Keno, Oreg. Minus gains estimate from Spencer Creek.

2

82 Spencer 

Creek

Headwaters to mouth 27 USGS gage 10/1925–

09/1931

Index regression to Rogue River 

above Prospect, Oreg. (USGS Site 14328000)

USGS Site 11510000. 

Restarted in 2002 by OWRD

3

83 Fall Creek Headwaters to mouth 36 USGS gage 07/1928–

09/1959

Index regression to McCloud R 

near McCloud CA (USGS Site 11367500)

USGS Site 11512000 2

84 Jenny Creek Headwaters to mouth 9 USGS gage 10/1922–

09/1928

Index regression to South Fork Little 

Butte Cr near Lake Creek, Oreg. (USGS Site 14341500)

USGS Site 11516500 3

85 Klamath River Below JC Boyle 

powerplant (RM 218.1) to Iron Gate Dam

92 USGS gage and 

Pacific Corp. Reservoir data

10/1967–

09/2000

Average. Mass balance from 

monthly mean discharge, reservoir content data, and tributary flow listed in table. Excludes gains from tributaries listed in table.

Klamath River below JC 

Boyle powerplant near Keno, Oreg. (USGS Site 11510700) to Klamath River below Iron Gate Dam, Calif. (USGS Site 11516530). Minus gain estimates from tributaries.

3

Subtotal for Klamath River below Keno 350
Manuscript approved for publication, April 4, 2007

Prepared by the USGS Publishing Network, 

Publishing Service Center, Tacoma, 

Bill Gibbs 

Donita Parker

Linda Rogers

Debra Grillo

Ginger Renslow

Bobbie Jo Richey

For more information concerning the research in this report, contact the 

Oregon Water Science Center Director

U.S. Geological Survey

10615 S.E. Cherry Blossom Dr.

Portland, OR 97216

http://or.water.usgs.gov
Printed on recycled paper

Gannett and others SIR 2007–5050 Ground-Water Hydrology of the Upper Klamath Basin, Oregon and California