U.S. Department of the Interior

U.S. Geological Survey

Georgian

Bay

Lake Erie

L

a

k

e

Mic

higan

Ontario

Lake

Lake Superior

Lake

Huron

O N T A R I O

P E N N S Y L VA N I A

N E W Y O R K

I L L I N O I S

I N D I A N A

O H I O

M I N N E S O T A

W I S C O N S I N

C A N A D A Q U E B E C

U N I T E D S T A T E S

M I C H I G A N

Irrigation Evapotranspiration

Groundwater 

well

Aquaculture 

instream use

Hydroelectric 

power generation 

instream use

Evaporation

Reservoir 

Livestock

Thermoelectric 

plant 

Reservoir water transfer for downstream withdrawals

Cooling 

tower

School

Groundwater

well

Domestic 

Wastewater

Wastewater

Lagoon

Sprinkler

Sprinkler

W2

S1

S1

RF2

C1, C2, RF2

RF2

RF1

W2

W2

S1

S2

C1

C1

C2

W2

W2

C3

W2

Public 

supply 

Well

Ecological 

 instream use

Recreation 

instream use

Pool 

Domestic delivery

Domestic

Commercial 

delivery 

Commercial 

delivery 

Commercial 

Industrial 

delivery

Industrial 

use 

Industrial 

use 

Pump house

Wastewater treatment 

Mining

Navigation 

instream use

Food 

factory 

Sewage

pretreatment

Reservoir

Factory 

Evaporation

Instream

flow 

School 

Evaporation

Evaporation

Golf 

course

D

D

S1 S1

S1

C1

C1

C1

C3

C1

C3

C1

C3

W1

RF1

RF1

RF3

RW

RF3

W2

W2

Recreation 

instream use

Septic tank 

and leachfield

RF2

C1, C2, RF2

RF2

RF2

Septic tank 

and leachfield

Evaporation

C1

FOOD

Plastics

● SOAP ●

Plastics

● SOAP ●

FOOD

LIQUID

FERTILIZER

Direction of water flow

Groundwater or surface-water 

withdrawals by a public supply

Groundwater or surface-water withdrawals 

by a self-supplied water user

Delivery of water from public-supply system

Release of wastewater into wastewater-collection 

system after use (sewer)

Movement of wastewater to a point of use

Return flow to surface water

Return flow to groundwater

Return flow from a wastewater-treatment plant

Delivery of reclaimed wastewater for use

Consumptive use from evaporation

Consumptive use from evapotranspiration

Consumptive use from product incorporation

EXPLANATION

RF1

RF2

RF3

RW

C1

C2

C3

W1

W2

D

S1

S2

Figure 1. Water use: Every which way, but always down gradient.

Self-supplied facilities withdraw water from a surfacewater or groundwater source and use the water for a 

specific purpose (domestic, irrigation, livestock, aquaculture, industrial, commercial, mining, and thermoelectric 

power). Public-supply facilities withdraw water from a 

surface-water or groundwater source, process the water 

through a water-treatment plant (occasionally, public 

suppliers will not treat water for purposes like industrialprocessing water), and deliver the water to users 

(domestic, commercial, industrial, and thermoelectric). 

During use, some water may be incorporated into 

products, evaporated, evapotranspired, or consumed 

(collectively referred to as “consumptive use”). The 

remaining water is released into a septic system or a 

wastewater-collection system. After wastewater treatment, 

the water is returned to a surface-water or groundwater 

resource or released to a reclaimed water-use facility.

Water-resource managers and planners 

require water-withdrawal, return-flow, and 

consumptive-use data to understand how 

anthropogenic (human) water use affects 

the hydrologic system. Water models like 

MODFLOW and GSFLOW use calculations 

and input values (including water-withdrawal and return flow data) to simulate and 

predict the effects of water use on aquifer 

and stream conditions. Accurate assessments 

of consumptive use, interbasin transfer, and 

areas that are on public supply or sewer are 

essential in estimating the withdrawal and 

return-flow data needed for the models. 

As the applicability of a model to real 

situations depends on accurate input data, 

limited or poor water-use data hampers the 

ability of modelers to simulate and predict 

hydrologic conditions. Substantial 

differences exist among the many agencies 

nationwide that are responsible for compiling water-use data including what data are 

collected, how the data are organized, how 

often the data are collected, quality assurance, required level of accuracy, and when 

data are released to the public. This poster 

presents water-use information and estimation methods summarized from recent 

Introduction

U.S. Geological Survey (USGS) reports 

with the intent to assist water-resource 

managers and planners who need estimates of monthly water withdrawals, 

return flows, and consumptive use (fig. 1). 

This poster lists references used in Shaffer 

(2009) for water withdrawals, consumptive 

use, and return flows. Monthly percent of 

annual withdrawals and monthly consumptive-use coefficients are used to compute 

monthly water withdrawals, consumptive 

use, and return flow for the Great Lakes 

Basin.

Table 3.  Estimated monthly water withdrawals for the Great Lakes Basin (U.S. and Canada) in billion gallons, 2006.

[Numbers were computed by multiplying 2006 annual water withdrawals from Great Lakes Commission (2010) and percentage of monthly water withdrawals (Shaffer, 2009). Numbers are rounded to three 

significant figures.] 

Water-use category Jan. Feb. March April May June July Aug. Sep. Oct. Nov. Dec.

Public supply 169 171 163 163 171 184 197 192 184 169 163 163

Self-supply domestic1 14.5 14.7 14.0 14.0 14.7 15.7 16.8 16.5 15.7 14.5 14.0 14.0

Self-supply industrial 132 132 129 130 135 140 145 151 147 142 135 130

Self-supply thermoelectric 

power

843 821 810 822 910 1,050 1,100 1,090 990 910 880 880

Self-supply irrigation .460 .460 1.23 3.38 7.05 23.8 47.8 45.7 15.3 4.91 2.45 .767

Self-supply livestock 3.58 4.14 3.83 3.88 3.99 4.60 5.16 5.57 4.29 4.04 4.09 3.93

Self-supply other2 10.1 10.5 11.8 13.9 14.9 17.0 16.6 18.4 18.2 15.8 13.2 11.2

Total 1,170 1,150 1,130 1,150 1,260 1,440 1,530 1,520 1,370 1,260 1,210 1,200

1

 Public supply monthly percentage of annual water withdrawals was used for self-supply domestic.

2

 Self-supply other is water used for fish/wildlife, environmental, recreation, navigation, and water-quality purposes. Specifically, water used to maintain levels for navigation, recreation, fish and wildlife 

habitat creation and enhancement, flow augmentation (or diversion), sanitation, pollution confinement, and other water-quality purposes and agricultural activities (services) other than those directly related 

to irrigation such as field drainage are included. Water used in temporary or immediate emergency situations (e.g., fighting forest or peat fires) also is reported here. As some of these water uses are included 

in the U.S. Geological Survey commercial water-use category, the monthly commercial coefficients were used. 

Table 2.  Monthly percentages of annual water withdrawals by water-use category for Ohio and Indiana combined, 1999–2004.

[Numbers are in percent; Irrigation, other is crop, nursery, and turf grass irrigation; Irrigation, all is the combination of golf course and crop, nursery, and turf grass irrigation in Ohio and Indiana; Other is the 

combination of aquaculture and commercial; IQR, Interquartile range (distance between the 75th and 25th percentile)] 

Water-use 

category Jan. Feb. March April May June July Aug. Sep. Oct. Nov. Dec.

Public Supply

Monthly percent 8.1 8.2 7.8 7.8 8.2 8.8 9.4 9.2 8.8 8.1 7.8 7.8

Indiana IQR 7.4—8.7 6.7—8.0 7.2—8.4 7.3—8.4 8.0—9.1 8.3—9.3 8.6—10.2 8.5—10.0 8.0—9.3 7.7—8.7 7.0—8.1 7.1—8.4

Ohio IQR 7.6—8.6 6.8—7.9 7.5—8.5 7.4—8.3 8.2—9.0 8.3—9.3 8.7—10.1 8.6—9.7 8.1—9.0 7.8—8.7 7.3—8.2 7.4—8.5

Industrial

Monthly percent 8.0 8.0 7.8 7.9 8.2 8.5 8.8 9.2 8.9 8.6 8.2 7.9

Indiana IQR 3.1—8.5 3.4—8.3 5.3—8.9 6.4—9.1 7.2—9.8 7.7—10.6 7.7—11.1 8.1—11.5 7.5—10.3 7.0—9.7 5.5—8.8 4.3—8.5

Ohio IQR 6.0—8.8 5.8—8.3 7.0—9.2 7.3—8.9 7.9—9.6 8.0—10.1 7.9—10.1 8.2—10.6 7.7—9.6 7.5—9.4 6.6—8.6 5.3—8.5

Thermoelectric

Monthly percent1 7.6 7.4 7.3 7.4 8.2 9.5 9.9 9.8 8.9 8.2 7.9 7.9

Indiana IQR 4.9—8.8 4.8—8.3 4.9—8.6 4.4—8.3 6.2—9.4 8.2—10.5 9.1—12.4 9.0—12.5 7.7—10.1 3.9—9.2 3.7—8.5 5.3—8.8

Ohio IQR 6.7—9.1 5.8—8.1 6.7—9.0 6.5—8.5 7.6—9.4 8.1—10.1 8.5—11.2 8.5—11.0 7.4—9.3 6.6—9.1 6.3—8.7 6.4—8.9

Irrigation, golf

Monthly percent2 .5 .3 .7 3.8 8.3 16.2 21.8 21.7 16.8 7.3 2.0 .6

Indiana IQR 0—0 0—0 0—0 0—4.5 2.2—11.6 11.0—20.0 17.1—27.9 18.2—29.2 12.3—22.0 1.3—10.3 0.0—0.4 0.0—0.0

Ohio IQR 0—0 0—0 0—0 0—3.4 0—11.8 10.5—20.6 18.7—30.7 17.9—30.3 10.0—20.2 0—9.1 0—0 0—0

Irrigation, other

Monthly percent3 .3 .3 .8 1.8 3.7 15.3 33.5 31.8 8.4 2.2 1.5 .4

Indiana IQR — nursery 0—0 0—0 0—6.2 0—9.4 0—12.8 9.3—17.9 9.3—24.0 11.5—24.4 9.8—21.3 2—12.8 0—7.0 0—0

Ohio IQR – nursery 0—.4 0—.6 0—4.0 0—8.1 5—13.1 11.2—20 13.9—24.7 13.7—25.0 8.9—16.8 1.3—11.0 0.0—4.7 0.0—0.9

Indiana IQR — crop 0—0 0—0 0—0 0—0 0—0 0—24.6 27.2—50 24.4—48.7 0.0—11.1 0—0 0—0 0—0

Ohio IQR — crop 0—.1 0—.1 0—.6 0—4.5 0—9.4 4.5—22.7 10.7—37.8 9.4—33.3 0—15.1 0—7.8 0—1.6 0—0

Irrigation, all

Monthly percent .3 .3 .8 2.2 4.6 15.5 31.2 29.8 10.0 3.2 1.6 .5

Livestock

Monthly percent 7.0 8.1 7.5 7.6 7.8 9.0 10.1 10.9 8.4 7.9 8.0 7.7

Indiana IQR 1.4—8.3 5.2—8.3 4.8—8.3 2.9—8.3 7.0—8.7 7.9—9.2 8.3—10.5 8.3—12.2 7.2—8.9 6.8—8.5 6.6—8.3 6.7—8.3

Ohio IQR 7.4—8.5 7.2—8.3 7.6—8.5 7.7—8.3 8.3—8.7 8.2—8.9 8.5—9.4 8.3—9.4 8.1—8.8 8.1—8.6 7.9—8.4 7.7—8.5

Aquaculture

Monthly percent4 8.2 6.9 8.9 10.9 8.5 10.3 7.4 7.6 8.0 7.8 7.7 7.8

Commercial

Monthly percent5 5.4 5.9 6.6 7.6 8.7 9.8 10.1 11.3 11.1 9.5 7.7 6.3

Indiana IQR .9—8.7 .8—8.4 2.2—8.8 4.1—9.1 6.6—10.6 5.4—12.0 5.7—15.3 7.1—14.5 7.7—11.8 5.5—10.0 2.4—8.5 1.4—8.3

Ohio IQR 0—8.5 0—8.3 .2—8.3 3.0—8.6 7.3—10.9 7.4—13.1 7.0—14.3 8.3—15.4 7.9—11.8 5.5—9.4 .6—8.3 0—8.3

Other

Monthly percent6 5.9 6.1 6.9 8.1 8.7 9.9 9.7 10.7 10.6 9.2 7.7 6.5

Mining

Monthly percent 5.2 6.0 7.6 9.5 9.4 9.7 9.1 9.2 9.2 9.3 8.8 7.0

Indiana IQR 0—7.9 0—7.8 5.4—9.4 7.7—11.1 8.3—12.0 8.2—11.8 8.0—11.9 7.8—12.1 7.4—11.4 7.8—11.6 6.5—9.5 3.3—8.3

Ohio IQR 0—8.3 0—8.2 4.6—9.1 8.0—10.9 8.3—11.5 8.2—11.4 8.0—11.3 8.0—11.8 8.0—11.1 7.9—11.5 6.9—9.9 4.4—8.5

1

 For rows to add up to 100 percent, thermoelectric (April) value of 7.3483 was rounded to 7.4 percent.

2

 For row to add up to 100 percent, golf-course irrigation (Aug.) value of 21.7521 was rounded to 21.7 percent.

3

 For row to add up to 100 percent, irrigation, other (Dec.) value of 0.455 was rounded to 0.4 percent.

4

 For row to add up to 100 percent, aquaculture (Aug.) value of 7.5497 was rounded to 7.6 percent

Estimating Monthly Water Withdrawals

Monthly data are of great value for understanding the effect of human activity in 

areas where there is the potential for seasonal water shortages and (or) water-quality 

stress on aquatic life. These shortages and 

stress periods tend to be in the summer and 

early fall when water temperatures are at 

their highest and streamflows and groundwater levels are at their lowest. Summer 

months and early fall (June, July, August, 

and September) also are when water withdrawals for most water-use categories are 

at their highest. Monthly or seasonal waterwithdrawal data should be used when available instead of annual withdrawal data. 

Table 2 lists monthly percentage of 

annual water withdrawals by water-use category for Indiana and Ohio. Monthly percentages of annual withdrawals may be used 

along with annual-withdrawal estimates 

to estimate monthly water withdrawal by 

water-use category when monthly data are 

unavailable. While the average for irrigation 

may be 21 percent in July, individual facilities may vary from 0 to 100 percent and 

half of the facilities (between the 25th and 

75th percentile or interquartile range) may 

vary from 10 to 40 percent for that month 

depending on local conditions and wateruse activities. This method is to provide a 

general estimate (and should be used with 

caution) when monthly data are not available. Shaffer (2009) graphs the distribution 

of monthly water withdrawals for individual 

records and the 25th and 75th percentiles by 

water-use category for Ohio and Indiana. 

The interquartile range (IQR; the distance 

between the 25th and 75th percentiles) and the 

number of records are listed on figures in 

Shaffer (2009) for Ohio and Indiana and are 

listed in table 2 for each water-use category 

and month. For commercial, public supply, 

industrial mining, and thermoelectric power, 

the IQR tended to be a lower range in the 

winter months than in the summer months. 

For example, the Ohio thermoelectric power 

IQR was 4.9 to 8.8 percent in January and 9.1 

to 12.4 percent in July. Golf course irrigation 

occurred mostly in April through October, 

while nursery irrigation tended to be March 

to November. Crop irrigation for Indiana 

was concentrated during June to September and was almost seven times of that for 

Ohio. Public-supply withdrawals in Ohio 

were more than two times the public-supply 

withdrawals in Indiana while industrial withdrawals in Indiana had were more than two 

times that of Ohio. The monthly percentages of annual water withdrawals for Ohio 

and Indiana (table 2) were used to compute 

monthly water-withdrawal estimates (table 3, 

fig. 2a and 2b) for the Great Lakes Basin 

(United States and Canada).

Table 5.  Estimated monthly consumptive use and return flow for the Great Lakes Basin in billion gallons, 2006.

[Numbers were computed by multiplying 2006 annual water withdrawals from Great Lakes Commission (2010), percentage of monthly water withdrawals (Shaffer, 2009), and monthly consumptive-use coefficients (Shaffer, 2009). Numbers are rounded to three significant figures]

Water-use category Jan. Feb. March April May June July Aug. Sep. Oct. Nov. Dec.

Great Lakes Basin consumptive use

Public supply 3.38 3.42 3.26 3.26 10.26 25.76 39.4 36.48 25.76 8.45 3.26 3.26

Self-supply domestic1 .290 .294 .280 .280 .882 2.20 3.36 3.14 2.20 .725 .280 .280

Self-supply industrial 14.5 15.8 14.2 14.3 14.8 16.8 17.4 18.1 16.2 15.6 16.2 15.6

Self-supply thermoelectric 

power

16.9 16.4 16.2 16.4 18.2 31.5 33.0 32.7 19.8 18.2 17.6 17.6

Self-supply irrigation2 .267 .304 .947 2.70 5.57 19.8 38.2 36.6 12.4 3.93 1.72 .614

Self-supply livestock 2.72 3.15 2.91 2.95 3.03 3.50 3.92 4.23 3.26 3.07 3.11 2.99

Self-supply other3 2.02 2.52 1.30 3.75 4.17 4.59 3.82 6.26 6.01 5.06 3.43 2.69

Great Lakes Basin return flow

Public supply 166 168 160 160 161 158 158 156 158 161 160 160

Self-supply domestic1 14.2 14.4 13.7 13.7 13.8 13.5 13.5 13.4 13.5 13.8 13.7 13.7

Self-supply industrial 117 116 115 116 120 123 128 133 131 126 119 114

Self-supply thermoelectric 

power

826 805 794 806 892 1,020 1,070 1,060 970 892 862 862

Self-supply irrigation .193 .156 .283 .676 1.48 4.05 9.56 9.14 2.91 .982 .735 .153

Self-supply livestock .859 .994 .919 .931 .958 1.10 1.24 1.34 1.03 .970 .982 .943

Self-supply other2 8.08 7.98 10.5 10.1 10.7 12.4 12.8 12.1 12.2 10.7 9.77 8.51

1

 Public supply percentage of monthly water withdrawals and consumptive use was used for self-supply domestic.

2

 Self-supply other consumptive use is the Great Lakes Commission (2010) self-supply other water withdrawals multiplied by commercial consumptive-use coefficients.

Table 4.  Consumptive-use percentage of withdrawals for Ohio, 1999–2004.

[Numbers are in percent of withdrawals; all irrigation is the combination of golf-course and crop, nursery, and turf grass irrigation in Ohio; Range; monthly min and max found for 1999–2004; IQR, Interquartile range (distance between the 75th and 25th percentile)]

Water-use category Jan. Feb. March April May June July Aug. Sep. Oct. Nov. Dec.

Public supply1 2 2 2 2 6 14 20 19 14 5 2 2

 Range 1—8 9—19 12—27 10—24 7—19 0—8

Industrial2 11 12 11 11 11 12 12 12 11 11 12 12

 IQR 0—37 0—37 0—39 0—40 0—37 0—39 0—40 0—40 0—41 0—40 0—37 0—35

Thermoelectric2 2 2 2 2 2 3 3 3 2 2 2 2

 IQR 0—7 0—8 0—8 0—6 0—10 0—12 0—15 0—16 0—7 0—7 0—8 0—13

Irrigation, all3 58 66 77 80 79 83 80 80 81 80 70 80

 IQR, golf course 1—99 42—98 65—98 67—95 68—98 68—99 37—98 0—94

 IQR, crop and nursery 67—93 68—91 65—90 68—90 66—93 60—92 56—90 37—84

Livestock4 76 76 76 76 76 76 76 76 76 76 76 76

Aquaculture5 4 3 7 8 5 9 5 5 6 3 2 1

Commercial6 20 24 11 27 28 27 23 34 33 32 26 24

 IQR 0—44 0—50 0—50 0—55 0—56 0—56 0—50 0—73 0—78 0—78 0—48 0—47

Mining6 23 24 21 15 18 18 19 19 19 19 19 16

 IQR 0—30 0—30 0—30 0—30 0—30 0—30 0—30 0—30 0—30 0—30 0—30 0—30

1

 Public-supply water withdrawals are delivered domestic, commercial, industrial, thermoelectric power users. Consumptive-use will depend on the amount delivered and what the water is used for. 

During the winter, consumptive use will be limited by processes including: humidifiers, indoor swimming pools, incorporation into products, cooking, and any processes that loses water to make steam. As 

these coefficients are for a region where outdoor water use is limited in the winter, the spring coefficient of 2 percent is used November to April.

2

 Industrial and thermoelectric-power consumptive-use coefficients were fairly steady for the year. The average consumptive-use coefficient computed by Shaffer (2009) was used for industrial. A number 

between the median and average consumptive-use coefficients was used for thermoelectric. 

3

 All irrigation monthly consumptive-use coefficients are the median record monthly consumptive-use coefficients excluding any records that had no withdrawals and records that had returns but no 

withdrawals. 

4

 Shaffer (2009) found an annual median consumptive-use coefficient of 76 percent based on 18 records. As no other data is available and livestock is less than 1 percent of Great Lakes Basin withdrawals, 

76 percent was used. There were not enough records to determine a IQR.

5

 The average consumptive-use coefficient was used for aquaculture. There were not enough records to determine a IQR.

6

 Shaffer (2009) found that the monthly median consumptive-use coefficients (based on percent) for Commercial and Mining water-use categories were different than the average (based on withdrawals). 

Averages based on percentages were computed for these categories and listed above.

Estimating Consumptive Use and Return Flow

Consumptive use is important because 

it is a way to estimate return flow when 

return-flow data are not available, and it is 

an important component of a water budget 

for water-resources planning and management. Consumptive use often is computed 

by using a consumptive-use coefficient; 

more detailed discussions on consumptive 

use and consumptive-use coefficients are 

contained in the following references:

• Pebbles (2003a, b) presented annotated 

bibliographies and discussions on consumptive-use coefficients.

• Shaffer and Runkle (2007) lists consumptive-use coefficients by water-use 

category for the Great Lakes Basin and 

climatically similar areas as well as 

selected statistics, an annotated bibliography, and an appendix with detailed 

consumptive-use coefficients.

• Shaffer (2009) analyzes data from Ohio 

and Indiana for consumptive-use coefficients.

Shaffer (2009) used three methods to 

compute annual, monthly and seasonal consumptive-use coefficients: the return flow 

and withdrawal method, the winter base-rate 

method and the standard industrial classification (findings are listed in tables 31, 32, 

and 9, respectively). Monthly consumptiveuse coefficients, the number of records, and 

the IQR for Ohio are listed in table 4 and 

were used to estimate consumptive use and 

return flow for the Great Lakes Basin for 

2006 (table 5 and fig.3). Thermoelectric 

power consumptive-use coefficients varied 

by type of cooling, but average coefficients 

tended to be higher in the summer months. 

Industrial average consumptive-use coefficients were steady for the year. Commercial 

and public supply consumptive-use coefficients were higher in the summer months.

0

200

400

600

800

1,000

1,200

1,400

1,600

1,800

Jan Feb Mar Apr May June July Aug Sept Oct Nov Dec

MONTH

WATER WITHDRAWALS, IN BILLION GALLONS

Industrial

EXPLANATION

Livestock

Thermoelectric power

Irrigation

Other

Public supply

Self-supplied domestic

Jan Feb Mar Apr May June July Aug Sept Oct Nov Dec

0

50

100

150

200

250

300

350

400

450

MONTH

WATER WITHDRAWALS, IN BILLION GALLONS

Industrial

EXPLANATION

Livestock

Irrigation

Other

Public supply

Self-supplied domestic

Fig. 2a (above) and 2b (below). Water withdrawals are highest during May - September and are affected by 

thermoelectric withdrawals. Irrigation and public-supply withdrawals also are highest during these months.

The availability of water-use data is constrained by legal reporting requirements in 

the study area, the time period, water-data 

resources, the data stream (how data are 

compiled and stored), and what data are 

needed (groundwater, surface water, wateruse categories, threshold data, locational 

data). To understand data reliability, waterresource managers, planners, and modelers 

should identify

1. their study area and water-use data 

needs,

2. available data resources, and 

3. data gaps and methods to estimate data.

Optimally, water-withdrawal, return-flow, 

and consumptive-use data that are reported 

by facilities themselves, or estimated data 

for similar types of facilities, are preferred 

over general estimates based on ancillary 

non-water data that may be related to a 

particular water-use category or groups of 

water-use categories.

Withdrawal and return-flow data are 

available from many State and Federal 

agencies. Below are some sources of withdrawal information and data that were used 

in Shaffer (2009) and can serve as a starting 

point for managers, planners, and modelers.

• State water-use data-collection programs 

may collect withdrawal data (and occaEstimating Annual Water Withdrawals

sionally, return-flow data) for one or 

multiple categories of water use. Ohio 

and Indiana have similar data-collection 

programs. The National Academy Press 

(2002) describes each State Water-Use 

Data Collection Program; for more 

recent program changes, check with 

each State program.

• The USGS water-use program estimates 

water use every 5 years (years ending 

in 0 and 5) at three levels: county, State, 

and national datasets (Kenny and others, 2009). Some States collect data by 

8-digit hydrologic unit code (subbasins). 

Additionally, data estimation methods, 

references, and State contact names 

are available at http://water.usgs.gov/

watuse/. While these data may not be 

sufficient for a detailed study, they can 

help prioritize areas or types of data. 

Also, USGS State contacts may have a 

list of references that may be helpful.

• The United States Department of Agriculture (USDA) National Agricultural 

Statistics Service estimates water used 

for irrigation every 5 years (years ending 

in 2 and 7) (United States Department of 

Agriculture – National Agricultural Statistics Service, 2002). The USDA also 

produces the Farm and Ranch Irrigation 

Survey (2007); estimates can be plotted 

by State and (or) county. While these 

data may not be sufficient for a detailed 

study, they can help prioritize areas or 

types of data. An interactive statistical mapping application is available at 

http://www.agcensus.usda.gov/Publications/2002/SVG/index.asp

• Thermoelectric power water-withdrawal 

data were collected by the U.S. Department of Energy Energy Information 

Administration (EIA) on form EIA767 

(U.S. Department of Energy, 2005). 

Data were collected from 1996 to 2005. 

For more information, see http://www.

eia.doe.gov/cneaf/electricity/page/

eia767.html

• Horn and others (2008) developed a 

regression model to estimate domestic 

water demand by census block based on 

domestic water-delivery data metered 

by community water systems and census data. Combining the public supply 

service areas with the regression equation provided estimates of self-supplied 

withdrawal. Combining sewered areas, 

the regression equation, and estimates of 

consumptive use provided estimates of 

domestic return flow. This methodology 

may be used for other studies to estimate 

domestic water use. 

One method that is commonly employed 

uses metered data from public-supplied 

facilities by region to estimate withdrawals from self-supplied facilities (Horn and 

others, 2008). Horn also estimated selfsupplied industrial withdrawals as a function 

of the number of employees. Sometimes 

the amount of a product produced is used to 

estimate water-use needs, and other datasets 

such as wastewater releases (stored in the 

U.S. Environmental Protection Agency PerCase Studies 

mit Compliance Database, PCS) are combined with consumptive-use information 

to estimate how much water is withdrawn 

to operate facilities. Horn also developed 

water-demand coefficients for specific 

types of commercial activities by using 

withdrawal and delivery data from the state 

water-use database and metered delivery 

data from community water systems.

Buchwald and others (in press) estimated 

commercial and industrial withdrawals by 

using a default withdrawal (based on the 

water-use purpose) and multiplying that by 

a coefficient and the permitted pumpage for 

Wisconsin. This method also could be used 

to estimate annual water withdrawals.

Shaffer (2009) used Ohio and Indiana 

data for 6 years and tiered median water 

withdrawals by water-use category (table 1)

to better understand water demand. Ohio 

and Indiana have similar water-use registration programs, thus making it possible to 

• Some return-flow data are available 

for the National Pollutant Discharge 

Elimination System Permit Compliance 

System. These data may be available 

through State Environmental Protection 

Agencies.

If annual withdrawal data are not available, 

water withdrawals may be estimated by (this 

is not an all-inclusive list)

• using an annual withdrawal rate based 

on water-use categories, groups, or 

Standard Industrial Classification (SIC) 

codes or using median daily-withdrawal 

rates based on water-use categories, 

groups, or SIC codes and multiplying 

the median water-withdrawal rate by 

365 days to obtain an estimated annual 

withdrawal;

• using satellite data, weather data, and 

crop-irrigation needs and irrigationsystem types and efficiencies to estimate 

crop withdrawals, applications, and ET 

use;

• using historical data or data available for 

another year; and

• using ancillary non-water data that may 

be related to a particular water-use category or groups of water-use categories 

such as number of employees or gross 

product to estimate water use.

combine and compare data. Combined, 

Ohio and Indiana comprised 17 percent 

of the United States industrial freshwater withdrawals in 2005, 12 percent of 

mining freshwater withdrawals, 10 percent of thermoelectric power freshwater 

withdrawals, 7 percent of self-supplied 

domestic withdrawals, and 5 percent 

of public-supply withdrawals (Shaffer, 

2009). 

Table 1.  Water demand by water-use category and facility size for Ohio and Indiana, 1999–2004.

[Facility size was computed by percentiles of withdrawals for records; “small” is less than the 33rd percentile; “medium” is from the 

33rd to 66th percentiles; “large” is from the 66th to 90th percentiles; “very large” is from the 90th to 98th percentiles; and “extra large” 

is greater than the 98th percentile; Mgal/d, million gallons per day; N, number of records; <, less than; the sum of “Percent of total withdrawals” may not equal 100 owing to rounding.]

Water-use category Facility size N Median withdrawal 

(Mgal/year)

Percent of total 

withdrawals by 

water-use category

Public supply Small 2,157 25.6 1

Medium 2,160 102 5

Large 1,570 464 18

Very large 524 1,940 27

Extra large 131 14,700 49

Industrial Small 1,078 1.46 <1

Medium 1,078 32.8 1

Large 784 237 4

Very large 261 1,990 11

Extra large 66 47,400 84

Thermoelectric power Small 161 54.8 <1

Medium 160 8,940 6

Large 116 110,000 44

Very large 39 284,000 36

Extra large 10 449,000 14

Irrigation, golf Small 1,354 2.19 4

Medium 1,356 11.0 19

Large 918 25.6 33

Very large 327 51.1 24

Extra large 82 113 19

Irrigation, nursery Small 260 3.65 2

Medium 258 11.0 12

Large 188 40.2 29

Very large 63 153 38

Extra large 16 296 20

Irrigation, crop Small 2,822 3.65 5

Medium 2,037 18.2 18

Large 682 36.5 28

Very large 171 87.6 24

Extra large 171 270 24

Commercial Small 858 0.73 <1

Medium 855 3.65 2

Large 624 21.9 11

Very large 206 172 28

Extra large 51 1,330 59

Mining1 Small 496 7.3 1

Medium 495 142 14

Large 360 409 33

Very large 120 1,190 30

Extra large 31 3,440 22

1

 Mining numbers may include dewatering

Jan Feb Mar Apr May June July Aug Sept Oct Nov Dec

MONTH

CONSUMPTIVE USE, IN BILLION GALLONS

Industrial

EXPLANATION

Livestock

Thermoelectric power

Irrigation

Other

Public supply

Self-supplied domestic

0

20

40

60

80

100

120

140

160

Poster by: Kimberly H. Shaffer and Rosemary S. Stenback

Edited by: Bonnie Stich Fink

Layout by: Marta Anderson

Estimating Monthly Water Withdrawals, Return Flow, and Consumptive Use in the Great Lakes Basin

Fig. 3.  Consumptive-use was highest for thermoelectric power. Irrigation, public supply, and self-supplied domestic consumptive use was

highest during June to September.

Buchwald, C.A., Luukkonen, C.L., and 

Rachol, C.M., 2010 (in press), Estimation of groundwater use for a groundwater-flow model of the Lake Michigan 

Basin and adjacent areas, 1864–2005: 

U.S. Geological Survey Open File Report 

2010–5068.

Great Lakes Commission, 2010, Annual 

reports from the Great Lakes Regional 

Water Use Database Repository, representing 2006 water-use data: Ann Arbor, 

Mich., accessed January 5, 2010, at 

http://www.glc.org/wateruse/database/

pdf/2006%20Water%20Use%20Report.

pdf.

Horn, M.A., Moore, R.B.; Hayes, Laura, 

and Flanagan, S.M., 2008, Methods for 

and estimates of 2003 and projected water 

use in the Seacoast region, southeastern 

New Hampshire: U.S. Geological Survey 

Scientific Investigations Report 2007–

5157, 87 p., plus 2 apps. on CD-ROM, 

accessed January 5, 2010, at 

http://pubs.usgs.gov/sir/2009/5157.

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

Linsey, K.S., Lovelace, J.K., and Maupin, M.A., 2009, Estimated use of 

water in the United States in 2005: 

U.S. Geological Survey Circular 1344, 

52 p.

National Academy Press, 2002, Estimating water use in the United States: A new 

paradigm for the National Water-Use 

Information Program: Washington, D.C., 

National Academy of Sciences, 176 p.

Pebbles, Victoria, 2003a, Consumptive 

use in the Great Lakes Region and 

Basin—Annotated bibliography of 

selected references: Ann Arbor, Mich., 

Great Lakes Commission, 10 p.

Pebbles, Victoria, 2003b, Measuring and 

estimating consumptive use of the Great 

Lakes water: Ann Arbor, Mich., Great 

Lakes Commission, prepared in cooperation with the Water Withdrawal Subcommittee of the Water Resources Decision 

Support System Project, 18 p.

Shaffer, K.H., 2009, Variation in withdrawal, return flow, and consumptive 

use of water in Ohio and Indiana, with 

selected data from Wisconsin, 1999–2004: 

U.S. Geological Survey Scientific Investigations Report 2009–5096, 93 p.

Shaffer, K.H., and Runkle, D.L., 2007, Consumptive water-use coefficients for the 

Great Lakes Basin and climatically similar 

areas: U.S. Geological Survey Scientific 

Investigations Report 2007–5197, 191 p.

U.S. Department of Agriculture, 2007, 

Census of Agriculture, Farm and Ranch 

Survey accessed on March 31, 2010, at 

http://www.agcensus.usda.gov/Publications/2007/Online_Highlights/Farm_and_

Ranch_Irrigation_Survey/index.asp

U.S Department of Agriculture— National 

Agricultural Statistics Service, 2002, 2002 

Census of Agriculture Interactive Statistical Map, accessed January 5, 2010, at 

http://www.nass.usda.gov/Data_and_Statistics/SVG/index.asp

U.S. Department of Energy, 2005, Year 

2005 annual steam-electric plant operation 

and design data: Department of Energy 

Form EIA-767 data file, accessed January 

5, 2006, at http://www.eia.doe.gov/cneaf/

electricity/page/eia767.html

References Cited

Open-File Report 2010-1211

June 2010