U.S. Department of the Interior

U.S. Geological Survey

Fact Sheet 2006–3099

June 2006

Estimated Water Use in Wyoming During 2000

Printed on recycled paper

Introduction

The U.S. Geological Survey (USGS) 

has compiled and published estimates of 

water withdrawals every 5 years since 

1950. This series of water-use reports 

serves as one of the few sources of information about regional or national trends 

in water withdrawals (Hutson and others, 

2004).

In Wyoming, six categories—irrigation, mining, thermoelectric power, 

public supply, self-supplied domestic, 

and industrial—were included in the most 

Table 1.  Data sources and calculations used to estimate water withdrawals in Wyoming during 2000.

[Data sources listed in the References Cited section of this fact sheet.]

Category Data source Calculation

Irrigation Wyoming Agricultural Statistics Service, 1997, 2002, 2003 

(irrigated acres); Pochop and others, 1992 (crop consumptive-use coefficients).

Irrigated acres of each crop were multiplied by crop 

consumptive-use coefficients.

Mining Office of the State Inspector of Mines, 2001 (tons mined); 

Quan, 1988 (non-fuels coefficients); Denver Research 

Institute, 1981 (coal coefficients); Wyoming Oil and Gas 

Conservation Commission, 2002, 2003 (oil, gas, and 

coalbed natural gas water-use estimates).

Oil, gas, and coalbed natural gas water-use estimates were 

reported by Wyoming Oil and Gas Conservation Commission. Total tons of other commodities were multiplied 

by water-use coefficients. 

Thermoelectric Seven operators in the State were contacted directly. Withdrawals were reported by individual facilities.

Public supply Major suppliers contacted directly. U.S. Census Bureau, 

2003a, 2003b (population), and 1990 and 1995 USGS 

water-use compilations (coefficient); Wyoming Water 

Development Commission, 2002a, 2002b (withdrawals 

and population); U.S. Environmental Protection Agency, 

2002a, 2002b (population).

Some withdrawals were reported by the Wyoming Water 

Development Commission or suppliers. Withdrawals for 

suppliers not responding were estimated by using population multiplied by 250 gallons per day per person.

Self-supplied domestic U.S. Census Bureau, 2003a, 2003b (population) and 1990 

and 1995 USGS water-use compilations (coefficient).

Self-supplied domestic population was calculated by subtracting the population supplied by public water systems 

from the total county population. Per-capita water-use 

withdrawals were estimated by multiplying the self-supplied county population by a per capita-use coefficient of 

75 gallons per day per person. 

Industrial U.S. Department of Labor, 2003 (employment); U.S. Army 

Corps of Engineers, 1987 (coefficients).

Employment by Standard Industrial Classification (SIC) 

code was compiled by county and multiplied by wateruse coefficients.

recent (2000) USGS compilation of estimated water use. For each category, withdrawal volumes were compiled by water 

source (surface water or ground water), 

and by county. Irrigation, public supply, 

and industrial ground-water withdrawals 

also were compiled by aquifer. With the 

exception of saline ground-water mining 

withdrawals totaling 222 million gallons 

per day (Mgal/d), all withdrawals in 

Wyoming were freshwater. Estimated 

withdrawals are listed from largest to 

smallest throughout this fact sheet.

How Was Water Use Estimated?

Various methods were employed 

to estimate water withdrawals by category in 2000 (table 1). Methods used 

to estimate withdrawals during previous 

compilations were reviewed and used if 

applicable for 2000. Site-specific data 

were collected if available for a wateruse category (mining and thermoelectric) 

because this is the most accurate compilation technique. However, for many categories, site-specific data were available 

for only the largest users (public supply).

Surveys were sent to obtain a selective sampling of typical water users in a 

water-use category (public supply and 

domestic). Water withdrawals were estimated using water-use coefficients and 

ancillary data for categories lacking sitespecific data (irrigation, mining, public 

supply, and industrial).

Water-supply well in northeast Wyoming.

Crop irrigation from the High Plains aquifer.
Figure 1.  Estimated water withdrawals by category and source in Wyoming during 2000.

Figure 2.  Estimated total, irrigation, and public-supply water withdrawals by county in

Wyoming during 2000.

Ground-water

withdrawals

54 percent

(57.2 Mgal/d)

Surface-water

withdrawals

46 percent

(49.4 Mgal/d)

Ground-water withdrawals

 15 percent (763 Mgal/d)

Surface-water withdrawals

85 percent (4,400 Mgal/d)

Sources of irrigation withdrawals

Sources of public-supply

withdrawals

Sources of total withdrawals

Total withdrawals by water use

Water use, in million gallons per day (Mgal/d)

Irrigation (4,500 Mgal/d)

 Mining (301 Mgal/d)

 Thermoelectric

 (243 Mgal/d)

EXPLANATION

Public supply (107 Mgal/d)

Self-supplied domestic 

 (6.57 Mgal/d)

Industrial (5.78 Mgal/d)

Ground-water withdrawals

 9 percent (413 Mgal/d)

Surface-water withdrawals

91 percent (4,090 Mgal/d)

111° 110° 109° 108° 107° 106° 105°

41°

42°

43°

44°

45°

0

0

50

50

100 MILES

100 KILOMETERS EXPLANATION

Total estimated water use by county, 

 in million gallons per day

Total estimated irrigation water use by county, in million 

 gallons per day, and rank of county estimated 

 irrigation water use in parentheses

Total estimated public-supply water use by county, in 

 million gallons per day, and rank of county

 estimated public-supply water use in parentheses

313 (6)

3.38 (11)

LINCOLN

177 (13)

8.01 (4)

UINTA

183 (12)

5.14 (10)

SWEETWATER

92.6 (17)

8.91 (3)

CONVERSE

188 (11)

2.37 (16)

NIOBRARA

60.9 (20)

0.36 (23)

ALBANY

336 (5)

6.60 (6)

WESTON

21.7 (23)

1.32 (20)

CROOK

65.5 (19)

6.81 (5)

CAMPBELL

42.1 (21)

1.88 (17)

SHERIDAN

220 (9)

5.54 (9)

JOHNSON

119 (16)

1.12 (21)

77.1 (18)

1.35 (19)

HOT

SPRINGS

WASHAKIE

168 (15)

0.30 (22)

BIG HORN

387 (3)

2.96 (14)

PARK

338 (4)

2.99 (13)

TETON

39.1 (22)

6.16 (8)

SUBLETTE

238 (8)

2.55 (15)

FREMONT

411 (1)

6.58 (7)

LARAMIE

198 (10)

1.51 (1)

PLATTE

255 (7)

1.87 (18)

NATRONA

173 (14)

12.1 (2)

174 (14)

CARBON

313 (6)

3.38 (11)

Greater than 300

150 to 300

Less than 150

LINCOLN

177 (13)

8.01 (4)

UINTA

183 (12)

5.14 (10)

CONVERSE

188 (11)

2.37 (16)

ALBANY

336 (5)

6.60 (6)

CROOK

65.5 (19)

6.81 (5)

CAMPBELL

42.1 (21)

1.88 (17)

SHERIDAN

220 (9)

5.54 (9)

JOHNSON

119 (16)

1.12 (21)

77.1 (18)

1.35 (19)

HOT

SPRINGS

WASHAKIE

168 (15)

0.38 (22)

BIG HORN

387 (3)

2.96 (14)

PARK

338 (4)

2.99 (13)

TETON

39.1 (22)

6.16 (8)

SUBLETTE

238 (8)

2.55 (15)

FREMONT

411 (1)

6.58 (7)

LARAMIE

198 (10)

15.1 (1)

PLATTE

255 (7)

1.87 (18)

GOSHEN

397 (2)

3.04 (12)

CARBON

313 (6)

3.38 (11)

What Are Some of the Major Uses 

of Water in Wyoming?

Estimated water use totaled about 

5,160 Mgal/d during 2000 (fig. 1). Most 

(85 percent) of the water used was 

withdrawn from surface-water sources. 

Ground-water withdrawals accounted for 

the remaining 15 percent of water used. 

Irrigation withdrawals accounted for 

87 percent of the estimated total water 

use in the State. Ninety-one percent of 

the water used for irrigation was from 

surface-water sources and the remaining 

9 percent was withdrawn from groundwater sources. Public-supply withdrawals accounted for about 2 percent of the 

estimated total water use in the State and 

was the fourth most prevalent water use. 

Estimated water use for public supply 

was relatively evenly divided between 

ground water (54 percent) and surface 

water (46 percent).

Was Estimated Water Use Evenly 

Distributed Across the State?

Estimated water use was compiled 

by county in 2000. Seven counties 

had estimated total water withdrawals 

exceeding 300 Mgal/d (fig. 2). Fremont 

County had the largest estimated total 

water use (433 Mgal/d). Fremont County 

also led the State in estimated irrigation 

use (411 Mgal/d). Because irrigation use 

constitutes the majority of total water 

use, counties with large estimated irrigation water use generally ranked high in 

estimated total water use (fig. 2). Weston 

County had the lowest estimated total 

water use (24.8 Mgal/d) in the State. 

Estimated public-supply use was greatest 

in Laramie (15.1 Mgal/d) and Natrona 

Counties (12.1 Mgal/d), home to Wyoming’s two largest cities (Cheyenne and 

Casper).

What are the Sources of Ground 

Water?

The availability of ground water in 

the State is determined largely by geology. Rock type largely determines the 

water-yielding characteristics of aquifers 

and aquifer systems (Whitehead, 1996). 

Aquifers that are at or near land surface 
131

827 1,270

10,000

15,100

0

2,000

4,000

6,000

8,000

10,000

12,000

14,000

16,000

Rhode Island

National average (U.S.)

Western U.S.

Wyoming

Idaho

GEOGRAPHIC AREA

ESTIMATED FRESH

WATER USE IN GALLONS PER 

DAY PER PERSON

Figure 3.  General extent of principal aquifers and aquifer systems at or near land surface in

semiconsolidated and consolidated rocks in Wyoming.

Figure 4.  Summed irrigation, public supply,

and industrial ground-water withdrawals

by principal aquifer or aquifer system in

Wyoming during 2000.

Figure 5.  Per-capita freshwater use in

Wyoming compared to other geographic

areas in the U.S. in 2000.

111° 110° 109° 108° 107° 106° 105°

41°

42°

43°

44°

45°

Colorado Plateaus

High Plains

Lower Cretaceous

Lower Tertiary

Note: Principal alluvial aquifers that 

occur along major watercourses are 

not shown on this map.

Other rocks (not a principal

 aquifer or aquifer system)

Upper Cretaceous

Upper Tertiary

Northern Great Plains

Principal aquifer or aquifer system

EXPLANATION

0

0

50

50

100 MILES

100 KILOMETERS

Modified from Principal Aquifers,

1:5,000,000, The National Atlas of the 

United States of America, U.S. Geological Survey, 2003

FREMONT

CARBON

ALBANY

BIG HORN

LARAMIE

SWEETWATER

NATRONA

PLATTE

GOSHEN

CONVERSE

PARK

SHERIDAN

SUBLETTE

UINTA

LINCOLN

CAMPBELL

JOHNSON WASHAKIE

HOT SPRINGS

NIOBRARA

CROOK

TETON

WESTON

Paleozoic

High Plains–62 percent (293 Mgal/d)

Lower Tertiary–less than 1 percent (1.88 Mgal/d)

Other–1 percent (3.3 Mgal/d)

Paleozoic–2 percent (8.66 Mgal/d)

Upper Tertiary–less than 1 percent (1.61 Mgal/d)

Lower Cretaceous–less than 1 percent (0.95 Mgal/d)

Upper Cretaceous–less than 1 percent (0.02 Mgal/d)

Principal aquifer or aquifer system–withdrawals 

 in millon gallons per day (Mgal/d)

EXPLANATION

Colorado Plateaus–5 percent (22.7 Mgal/d)

Northern Great Plains–16 percent (75.7 Mgal/d)

Alluvial–14 percent (67.1 Mgal/d)

and that consist primarily of semiconsolidated and consolidated rocks are shown 

in figure 3. An aquifer system is composed of two or more aquifers, often vertically stacked, that are grouped together 

because of physical connection or sharing 

of similar geologic and hydrologic 

characteristics that are best described and 

studied together. Consequently, aquifers 

that readers may be familiar with (such as 

the Madison aquifer) are not shown separately on figure 3 because they are either 

buried below another aquifer or they are 

grouped with other aquifers into an aquifer system. Unconsolidated deposits and 

consolidated sedimentary rocks are the 

most productive aquifers, whereas crystalline rocks generally are less permeable 

and less productive (Whitehead, 1996).

Withdrawals of ground water for 

irrigation, public supply, and industrial categories during 2000 totaled 

about 475 Mgal/d (fig. 4). The High 

Plains aquifer was the source of about 

62 percent of those water withdrawals. 

Although mining constitutes a substantial part of total ground-water use 

(about 280 Mgal/d), the category was 

not summed with other ground-water 

withdrawals in figure 4 because estimates 

were not made by principal aquifer or 

aquifer system.

How Does Wyoming’s Estimated 

Per-Capita Freshwater Use 

Compare to Other States?

Estimated per-capita total freshwater 

use in Wyoming during 2000 was about 

10,000 gallons per day per person (fig. 5). 

That value was the second largest in the 

country; only Idaho (15,100 gallons per 

day per person) was greater (fig. 5). The 

State with the lowest estimated per-capita 

total freshwater use during 2000 was 

Rhode Island (fig. 5). For comparison 

purposes, the average estimated percapita total freshwater use for the entire 

United States (U.S.) and for the Western 

U.S. (17 western-most states in the U.S., 

not including Alaska and Hawaii) also 

are shown on figure 5. Large estimated 

per-capita freshwater use values are 

typical for sparsely populated States that 

withdraw substantial amounts of water 

for irrigation (Solley and others, 1993).
Seminoe Dam in south-central Wyoming.

What Factors Affect Water 

Availability in Wyoming?

Three natural factors—climate, geology, and physical geography—primarily 

determine the availability of surface 

water and ground water for various uses 

in Wyoming. In addition, the location 

and extent of infrastructure associated 

with irrigation and flood control (dams 

and canals) determine when and where a 

large proportion of Wyoming’s water use 

occurs.

Climate varies substantially across 

the State. Precipitation is highest in 

the mountains where annual totals may 

exceed 30 inches per year. However, precipitation is less than 15 inches annually 

in the semiarid high plains and intermontane basins that comprise more than 

three-fourths of the State’s land surface. 

In addition, natural variations in climate 

from year to year determine how much 

water is available for various uses in any 

given year.

The physical characteristics of rocks 

within the State (geology), in combination with climate and physical geography, 

affect the amount, location, and movement of water—both on the land surface 

in streams and below it in aquifers. 

Because climate, geology, and physical 

geography vary considerably based on 

location, and climate also varies through 

time, the amount of water available for 

use at a given location in Wyoming can 

vary considerably.

Estimates of the amount, source, and 

location of surface- and ground-water use 

are an important component in an overall 

strategy to plan for future water needs of 

the State.

References Cited

Denver Research Institute, 1981, Water and 

energy in Colorado’s future—The impacts of 

energy development on water use in 1985 and 

2000: Boulder, Colo., Westview Press, 303 p.

Hutson, S.S., Barber, N.L., Kenny, J.F., Linsey, 

K.S., Lumia, D.S., and Maupin, M.A., 2004, 

Estimated use of water in the United States in 

2000: U.S. Geological Survey Circular 1268, 

46 p.

Office of the State Inspector of Mines, 2001, 

Annual report of the State Inspector of Mines 

of Wyoming for the year ending December 

31, 2000, 81 p.

Pochop, Larry, Teegarden, Travis, Kerr, Greg, 

Delaney, Ronald, and Hasfurther, Victor, 

1992, Consumptive use and consumptive 

irrigation requirements in Wyoming: Laramie, 

University of Wyoming, Water Resources 

Research Institute report 92-06, 59 p.

Quan, Choon Kooi, 1988, Water use in the 

domestic nonfuel minerals industry: U.S. 

Bureau of Mines Information Circular 9196, 

62 p.

Solley, W.B., Pierce, R.R., and Perlman, H.A., 

1993, Estimated use of water in the United 

States in 1990: U.S. Geological Survey Circular 1081, 76 p.

U.S. Army Corps of Engineers, 1987, IWR-Main 

water use forecasting system version 5.1 

user’s manual and system description: IWR 

Report 88-R-6, various pagination.

U.S. Census Bureau, 2003a, Population, housing units, area, and density—2000: accessed 

March 6, 2003, at http://factfinder.census.

gov/servlet/GCTTable?ds_name=DEC_2000_

SF1_U&geo_id=04000US56&_box_head_

nbr=GCT-PH1&format=ST-7

U.S. Census Bureau, 2003b, Wyoming county 

populations: accessed March 11, 2003, at 

http://factfinder.census.gov/servlet/DTTable?_

ts=65472682425

U.S. Department of Labor, 2003, Bureau of 

Labor statistics, covered employment and 

wages: accessed February 2, 2003, at http://

data.bls.gov/labjava/outside.jsp?survey=ew

U.S. Environmental Protection Agency, 2002a, 

Public drinking water systems—Facts and figures: accessed March 7, 2003, at http://www.

epa.gov/safewater/pws/factoids.html

U.S. Environmental Protection Agency, 2002b, 

Safe Drinking Water Query: accessed February 22, 2002, at http://oaspub.epa.gov/enviro/

sdw_form.create_page?state_abbr=WY

U.S. Geological Survey, 2003, Principal aquifers, 

in National Atlas of the United States of 

America, 1 sheet, accessed October 5, 2005, 

at http://nationalatlas.gov/mld/aquifrp.html

Whitehead, R.L., 1996, Ground-water atlas of 

the United States—Segment 8, Montana, 

North Dakota, South Dakota, Wyoming: U.S. 

Geological Survey Hydrologic Investigations 

Atlas 730-I, 24 p.

Wyoming Agricultural Statistics Service, 1997, 

U.S. Census of Agriculture—Farm and ranch 

irrigation survey: accessed December 10, 

2002, at http://www.nass.usda.gov/census/

census97/fris/tbl04.pdf

Wyoming Agricultural Statistics Service, 2002, 

Wyoming Agricultural Statistics Book: 

accessed December 10, 2002, at http://www.

nass.usda.gov/wy/bulletin/bultntoc.htm

Wyoming Agricultural Statistics Service, 2003, 

county data: accessed February 25, 2003, 

at http://www.nass.usda.gov/wy/internet/

cntydata.htm

Wyoming Oil and Gas Conservation Commission, 2002, 2000 County report with percentage of State total: accessed June 3, 2002, at 

http://wogcc.state.wy.us/cfdocs/2000STATS_

files/sheet003.htm

Wyoming Oil and Gas Conservation Commission, 2003, Download menu—020503_CBM 

data in Excel (zipped): accessed on March 

12, 2003, at http://wogcc.state.wy.us/

urecordsMenu.cfm?Skip=’Y’&oops=ID7670

Wyoming Water Development Commission, 

2002a, Wyoming Water Development Commission 2000 Water System Survey Report, 

System Data: accessed January 29, 2003, at 

http://wwdc.state.wy.us/watsys/2000/system.

html

Wyoming Water Development Commission, 

2002b, Wyoming Water Development Commission 2000 water system survey report, 

system use: accessed January 29, 2003, 

at http://wwdc.state.wy.us/watsys/2000/

wateruse.html

For additional information on water

use, visit the USGS Web site at

http://water.usgs.gov/watuse/

or contact:

Director

Wyoming Water Science Center

U.S. Geological Survey

2617 E. Lincolnway, Suite B

Cheyenne, WY 82001

(307) 778-2931

E-mail: state_rep_wy@usgs.gov

By Gregory K. Boughton, Kendra R. Remley, 

and Timothy T. Bartos

Layout and design by Suzanne C. Roberts