WATER WITHDRAWAL AND USE IN MARYLAND, 1990-91

By Judith C. Wheeler

U.S. GEOLOGICAL SURVEY

Water-Resources Investigations Report 93-4225

Prepared in cooperation with the

MARYLAND WATER RESOURCES ADMINISTRATION and the 

MARYLAND GEOLOGICAL SURVEY

Towson, Maryland 

1995
U.S. DEPARTMENT OF THE INTERIOR

BRUCE BABBITT, Secretary

U.S. GEOLOGICAL SURVEY

Gordon P. Eaton, Director

For additional information write to: Copies of this report can be purchased from:

District Chief

U.S. Geological Survey, WRD 

208 Carroll Building 

8600 La Salle Road 

Towson, Maryland 21286

U.S. Geological Survey 

Earth Science Information Center 

Open-File Reports Section 

Box 25286, MS 517 

Denver Federal Center 

Denver CO 80225
CONTENTS

Glossary ..........................................................................................................................................................v

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

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

Purpose and scope.............................................................................................................................2

Methods of data collection and estimation........................................................................................ 3

Water use .........................................................................................................................................................4

Population and water-use trends...................................................................................................... 10

Public supply.................................................................................................................................. 10

Domestic .........................................................................................................................................11

Commercial..................................................................................................................................... 11

Industrial ......................................................................................................................................... 11

Mining............................................................................................................................................. 15

Thermoelectric power..................................................................................................................... 15

Hydroelectric power .................................................................................................................. 15

Livestock......................................................................................................................................... 15

Irrigation.......................................................................................................................................... 15

Aquaculture..................................................................................................................................... 16

Summary........................................................................................................................................................ 16

Selected references........................................................................................................................................ 18

Appendix: Water withdrawal and use data for Maryland, 1990-91............................................................... 21

FIGURES

1. Map showing the counties of Maryland and selected adjacent counties of Virginia,

West Virginia, and Pennsylvania....................................................................................................... 3

2. Map showing freshwater withdrawals in Maryland, by county, 1990-91................................. 6

3. Bar charts showing freshwater withdrawals and source of water in

Maryland, by category of use, 1990-91........................................................................................... 7

4. Maps showing fresh surface-water and ground-water withdrawals in

Maryland, by county, 1990-91.......................................................................................................... 8

5. Map and bar charts showing fresh surface-water and ground-water

withdrawals in Maryland, by principal drainage basin, 1990-91..................................................... 9

6. Maps and bar chart showing ground-water withdrawals in

Maryland, by principal aquifers, 1990-91...................................................................................... 12

7. Graph showing population and freshwater withdrawals in Maryland, 1950-91.................. 14

TABLES

1. Maryland water suppliers cross-boundary withdrawals and deliveries, 1990-91................................. 5

2. Population and water use in Maryland, 1990-91................................................................................. 14

3. Total water withdrawals (excluding hydroelectric power) in Maryland, by county

a. 1990....................................................................................................................................22

b. 1991....................................................................................................................................23

4. Public-supply water withdrawals and deliveries in Maryland, by county

a. 1990....................................................................................................................................24

b. 1991....................................................................................................................................25

Contents III
TABLES- (Continued)

5. Domestic water withdrawals (self-supplied) and deliveries from public suppliers in 

Maryland, by county: 

a. 1990................................................................................................................................... 26

b. 1991....................................................................................................................................27

6. Commercial freshwater withdrawals (self-supplied) and deliveries from public suppliers in 

Maryland, by county: 

a. 1990....................................................................................................................................28

b. 1991....................................................................................................................................29

7. Industrial water withdrawals (self-supplied) and deliveries from public suppliers in 

Maryland, by county: 

a. 1990....................................................................................................................................30

b. 1991.................................................................................................................................... 31

8. Mining water withdrawals in Maryland, by county:

a. 1990................................................................................................................................... 32

b. 1991................................................................................................................................... 33

9. Thermoelectric power water withdrawals in Maryland, by county:

a. 1990.................................................................................................................................... 34

b. 1991................................................................................................................................... 35

10. Hydroelectric power water use in Maryland, by county:

a. 1990....................................................................................................................................36

b. 1991....................................................................................................................................37

11. Livestock water withdrawals in Maryland, by county, 1990-91...................................................... 38

12. Irrigation water withdrawals in Maryland, by county:

a. 1990.................................................................................................................................... 39

b. 1991................................................................................................................................... 40

13. Aquaculture water withdrawals in Maryland, by county:

a. 1990....................................................................................................................................41

b. 1991....................................................................................................................................42

IV Contents
GLOSSARY

[Definitions modified from Solley and others, 1988; Maryland Water Resources 

Administration, 1987; and Drever, 1982]

Agriculture (nonirrigation) water use. Water used for livestock watering, feedlots, dairy operations, 

and other farm needs. Livestock includes cattle, dairy cows, sheep, hogs, and poultry.

Aquaculture. The controlled production of finfish, shellfish, and aquatic plants in fresh and saline water; 

also called fish farming or fish culture.

Aquifer. A rock unit (including unconsolidated sediments) that will yield water in a usable quantity to 

wells or springs.

Brackish water. Water that is too saline to be potable, but is significantly less saline than seawater. Total 

dissolved solids (TDS) concentration in brackish water ranges from 1,000 to 20,000 mg/L 

(milligrams per liter), whereas TDS concentration in seawater is about 35,000 mg/L.

Commercial water use.-- Water withdrawn for motels, hotels, restaurants, office buildings, and other 

commercial facilities, and for educational, civilian, and military institutions. Laboratories and 

research facilities are also included in this category. Water can be obtained from a public supply or 

can be self-supplied.

Consumptive use (consumed water) .- That quantity of water withdrawn that is evaporated, transpired, 

incorporated into products or absorbed by crops, consumed by humans or livestock, or otherwise 

removed from the immediate water environment.

Cooling water.-- Water used to cool condensers, nuclear reactors, and other commercial and industrial 

equipment.

Domestic water use . Water that is obtained from a public supply or is self-supplied and used for

household purposes such as drinking, food preparation, bathing, washing dishes and clothes, 

flushing toilets, and watering lawns and gardens. Water withdrawn for home heating and cooling 

by ground-water heat pumps is also included in this category.

Evaporation.-- The process by which water is changed from a liquid to a vapor phase.

Freshwater.-- Water that contains less than 1,000 milligrams per liter (mg/L) of TDS; generally, more than 

500 mg/L of TDS in water is undesirable for drinking and many industrial uses.

Ground water.- Generally, all subsurface water, as distinct from surface water; specifically, that part of 

subsurface water in the saturated zone (a zone in which all interconnected openings are filled with 

water) where the water is under pressure equal to or greater than that of the atmosphere.

Hydroelectric water use.- Water used in the generation of electricity at power plants where the turbine 

generators are driven by falling water; an instream use.

Industrial water use.- Water used for manufacturing or processing purposes, such as fabrication;

washing, cooling, and separation processes; and boiler make-up. Includes use by industries such 

as steel, chemical and allied products, shipbuilding, petroleum refining, truck assembly, printers 

and publishers, clothing manufacturers, paper and allied products plants, and food and seafood 

processors.
Instream use.- Water use that takes place within the stream channel for such purposes as hydroelectricpower generation, navigation, water-quality improvement, fish propagation, and recreation.

Irrigation water use.-- Artificial application of water on the land surface to assist in the growing of farm 

and nursery crops or to maintain vegetative growth in recreational lands, such as parks and golf 

courses.

Mining water use.-- Water used for extracting minerals such as coal. Also includes uses associated with 

stone, sand, and gravel quarrying, dewatering, milling (crushing, screening, washing, flotation), 

and other preparations usually performed at the mine site or as part of a mining activity. 

Dewatering in the construction of subway tunnels is also included.

Public supply water use.-- Water withdrawn by public and private water suppliers and delivered for a 

variety of uses, such as domestic, commercial, and industrial. Public water suppliers include 

municipalities, towns, or counties having incorporated governments. Private water suppliers 

include unincorporated communities, subdivisions with central water supplies, trailer parks, 

apartment buildings, and migrant labor camps with independent supply systems.

Reclaimed wastewater. Wastewater-treatment-plant effluent that has been diverted or intercepted for 

use before it reaches a natural waterway or aquifer.

Saline water.- Water that contains more than 1,000 mg/L of TDS ("slightly saline"--!,000 to 3,000 mg/L; 

"moderately saline"-3,000 to 10,000 mg/L; "very saline"-! 0,000-35,000 mg/L).

Self-supplied water.- Water withdrawn by a user of a surface-water or ground-water source and not 

furnished by a public supply. Homes and small communities relying on individual wells are 

included in this category.

Surface water.- A body of water on the land surface, such as a stream or a lake.

Thermoelectric-power water use.- Water used in the process of the generation of electricity by other than 

hydroelectric processes.

Withdrawal.- Water diverted from a surface-water source or removed from an aquifer for use.

VI
WATER WITHDRAWAL AND USE IN MARYLAND, 1990-91

By Judith C. Wheeler

ABSTRACT

This report summarizes the results of a 

study by the U.S. Geological Survey, in cooperation with the Maryland Water Resources 

Administration and the Maryland Geological 

Survey, to estimate amounts of fresh and saline 

water withdrawn and used in Maryland during 

1990-91.

During 1990, about 1,460 Mgal/d (million 

gallons per day) of freshwater was withdrawn 

from surface-water and ground-water sources in 

Maryland. Of this amount, 1,210 Mgal/d (83 

percent) was used in the State and 248 Mgal/d 

(17 percent) was transferred to surrounding 

States and the District of Columbia for water 

supply. About 7.5 Mgal/d of freshwater was 

imported from bordering States for use in Maryland.

During 1991, total freshwater withdrawals 

in Maryland increased to about 1,500 Mgal/d, 

with 1,250 Mgal/d used in the State and 249 

Mgal/d transferred to surrounding States and 

the District of Columbia. About 6.6 Mgal/d of 

freshwater was imported from bordering States 

for use in Maryland.

During 1990-91, most freshwater withdrawals (1,220 Mgal/d during 1990 and 1,250 Mgal/d 

during 1991 or about 83 percent of total for each 

year) were from surface-water sources. The largest surface-water withdrawals in the State, 

greater than 100 Mgal/d, were in Montgomery 

and Baltimore Counties. Reservoirs and rivers in 

these counties were the sources for public suppliers that serve the Baltimore City and District of 

Columbia metropolitan areas. More than 70 percent of the fresh surface water (about 870 

Mgal/d during 1990 and 875 Mgal/d during 

1991) was withdrawn and used in the Potomac 

drainage basin whereas most ground water

(about 170 Mgal/d during 1990 and 184 Mgal/d 

during 1991) was withdrawn and used in the 

Upper Chesapeake drainage basin. The Potomac 

Group aquifers were the largest source of ground 

water (26.6 percent of total ground-water withdrawals) in each year.

The population of Maryland served by public water-supply systems increased slightly from 

3.94 million during 1990 to 3.97 million during 

1991. In addition, during the peak tourist season 

(from May to September), the Ocean City watersupply system served approximately 268,000 

more individuals than the base population of 

about 12,000. During both years, surface water 

was used by about 69 percent of the State's population and ground water was used by the 

remaining 31 percent.

Ten water-use categories represent the 

major demands on the surface-water and 

ground-water resources of the State during 1990- 

91: Public supply, domestic, commercial, industrial, mining, thermoelectric power, 

hydroelectric power, livestock, irrigation, and 

aquaculture.

Notable facts about these uses are:

 Public supply-798 Mgal/d of freshwater was withdrawn in 1990 (826 Mgal/d during 1991) and 

delivered for use to residences, commercial establishments, and industries, public suppliers 

withdrew the largest quantities of water in the 

State. The largest user of surface water for public 

supply was Baltimore City with about 135 Mgal/d 

withdrawn for use during 1990 and 127 Mgal/d 

during 1991.

 Domestic 484 Mgal/d of freshwater was used during 1990 (490 Mgal/d during 1991). About 414 

Mgal/d during 1990 and 420 Mgal/d during 1991 

were received from public suppliers. About 69.9 

Mgal/d during 1990 and 71.4 Mgal/d during 1991 

were self-supplied. All self-supplied domestic

Water Withdrawal and Use in Maryland, 1990-91 1
water withdrawals were from ground-water 

sources.

 Industrial 123 Mgal/d of freshwater was used during 1990 (116 Mgal/d during 1991). About 70.1 

Mgal/d during 1990 and 67.2 Mgal/d during 1991 

were self-supplied; the remaining water used was 

delivered by public suppliers. Industries also used 

379 Mgal/d of saline or brackish surface water during 1990 (312 Mgal/d during 1991). About 62.5 

Mgal/d of reclaimed wastewater was used during 

each year.

 Mining 28.0 Mgal/d of freshwater was used during 1990 (25.3 Mgal/d during 1991). Brackish or 

saline surface-water withdrawals used in mining 

operations decreased 82 percent from 21.3 Mgal/d 

in 1990 to 3.77 Mgal/d in 1991 due mainly to 

reduced dredging operations.

 Thermoelectric power 421 Mgal/d of freshwater was 

used during 1990 (416 Mgal/d during 1991). In 

addition, about 4,550 Mgal/d of saline surface 

water was withdrawn for cooling condensers during 1990. During 1991, saline surface-water 

withdrawals increased to 5,760 Mgal/d.

 Hydroelectric power (instream water use) 25,900 

Mgal/d of freshwater was used for the production 

of electricity during 1990 (21,900 Mgal/d during 

1991). Although the amount of water diverted 

through some plants was considerable, the amount 

of consumptive use was negligible.

 Livestock About 10.4 Mgal/d of freshwater was 

used during each year of the 2-year period. About 

2.44 Mgal/d was from surface-water sources and 

7.95 Mgal/d was from ground-water sources.

 Irrigation-29.1 Mgal/d of freshwater was used during 1990 (50.4 Mgal/d during 1991). Most of the 

water (22.8 Mgal/d during 1990 and 41.1 Mgal/d 

during 1991) was used for irrigating farm crops.

 Aquaculture--937 Mgal/d of freshwater was used 

during 1990 (11.6 Mgal/d during 1991). Saline surface-water withdrawals increased from 9.58 

Mgal/d during 1990 to 12.5 Mgal/d during 1991.

INTRODUCTION

Maryland has a total land and water area of 

12,303 mi 2 and is subdivided into 23 counties 

and Baltimore City (fig. 1). The State has abundant surface-water l and ground-water 

resources. As the demand for water increases, 

however, additional stress is placed on these 

resources. Effective water-resource management depends, in part, on current and accurate 

water-withdrawal and use data. Such data are 

valuable for evaluating effects of withdrawals on 

the State's water resources, identifying current 

water-use patterns, and estimating future water 

demands. The study on which this report is

1. Words that are bold are found in the 

"Glossary" section of the report.

based was conducted by the U.S. Geological Survey, as part of the National Water-Use 

Information Program of collecting and compiling reliable site-specific and aggregate water-use 

information at State and national levels. The 

study was conducted in cooperation with the 

Maryland Water Resources Administration 

(WRA) and the Maryland Geological Survey. 

The results of similar studies in 1986,1987, and 

1988-89 are summarized by Wheeler (1990,1991, 

and 1992).

Purpose and Scope

This report summarizes the amounts of 

fresh and saline water withdrawn and used in 

Maryland during 1990 and 1991. The water-use 

data are discussed briefly and presented in 

graphs, tables, and maps organized by counties, 

type of use, drainage basins, and aquifers.

In this report, the amount of water withdrawn from sources in each county is 

distinguished from the amount of water used in 

each county. Withdrawals in each county 

include all water withdrawn whether or not it is 

transferred to another county or State. Water use 

is the amount of water actually used in a particular county or drainage basin, including (1) water 

withdrawn for use in the county or basin and (2) 

water imported from another county, basin, or 

State. Amounts of self-supplied water and water 

delivered from public-supply systems are presented for each category of use.

The water-use categories discussed in this 

report are public supply, domestic, commercial, 

industrial, mining, thermoelectric power, hydroelectric power, livestock, irrigation, and 

aquaculture. Water withdrawn by a public or 

private water utility and delivered to a variety of 

users is designated as a "public supply." If a public supply is not available or is not used, the 

water is classified as "self-supplied." Homes and 

small communities relying on individual wells 

are classified as domestic self-supplied water 

users. Commercial use not only includes typical 

businesses such as restaurants, motels, car 

washes, and office buildings, but also institutions such as schools, churches, and military 

installations. Thermoelectric power includes 

electrical energy generated in steam-electric 

plants and those using nuclear fuel. Water used 

for the generation of electricity by hydroelectric

Water Withdrawal and Use in Maryland, 1990-91
79' 78' 77' 76' 75'

39'

38'

'PENNSYLVANIA '

o.... . Symbol shows location of water 

suppliers listed in table 2.

Figure 1. The counties of Maryland and selected adjacent counties of Virginia, West Virginia, and Pennsylvania.

power plants is also discussed in this report but 

the quantities of water used are not included in 

the fresh water totals because this is considered 

an "instream" water use and not a withdrawal-- 

that is, water use takes place within the stream 

channel at the dam, where turbine generators are 

driven by falling water.

Methods of Data Collection and Estimation

Most of the water-use data on public suppliers, commercial and industrial facilities, mines, 

and thermoelectric power plants were obtained 

from pumpage reports submitted to WRA by 

users withdrawing 0.01 Mgal/d or more. 

Monthly and annual withdrawal data are stored 

in a computerized data base by WRA. The U.S. 

Geological Survey, in cooperation with WRA 

and the Maryland Department of the Environment (MDE), maintains the Maryland SiteSpecific Water-Use Data System (SSWUDS), that 

is designed to store monthly water-withdrawal 

data from the WRA and return-flow data from 

the MDE for users that withdraw or return 0.01 

Mgal/d or more. The WRA's data base and

SSWUDS were used in the preparation of this 

report. Water-use data for users of less than 0.01 

Mgal/d were estimated from the average daily 

allocations established in water-appropriation 

and use permits which are required by WRA for 

all water users except self-supplied domestic 

users and agricultural irrigators using less than 

0.01 Mgal/d.

Data on domestic, hydroelectric power, livestock, and irrigation water use were estimated 

using the following methods:

Self-supplied domestic withdrawals were estimated by determining the percentage of yearround housing units not served by public suppliers (U.S. Department of Commerce, 1990b, 

p. 92) and multiplying that percentage by the 

total population for each county (1990 county 

population data from U.S. Department of Commerce, 1990ar table 1, p. 1-12 and 1991 county 

population data compiled from Maryland 

Department of State Planning, 1990). The total

Water Withdrawal and Use in Maryland, 1990-91 3
unserved population number was then multiplied by 80 gal/d, the estimated per capita 

water use in Maryland Q.R. Herring, Maryland 

Water Resources Administration, oral communv 1992).

Hydroelectric-power water use was estimated 

based on annual electric power generation data 

obtained from the Department of Energy, 

Energy Information Administration and a coefficient for water used per KWh (S.B. Weisberg, 

Martin Marietta Environmental Systems, written commun., 1986). Reported water-use data 

were used for some of the facilities.

Livestock water use was estimated based on the 

number of farm animals in each county (U.S. 

Department of Commerce, 1988) and the average amount of water used for drinking and 

maintenance per animal (U.S. Environmental 

Protection Agency, 1973, p. 15). Because the 

most recent agricultural census was conducted 

during 1987, the same number of animals and 

the same water use were assumed for 1990-91. 

The estimates also are based on the assumption 

that grazing animals such as cattle and sheep 

consumed surface water, and poultry, hogs, 

and dairy cows consumed ground water.

Irrigation water use for crops was estimated 

from the number of acres irrigated and amount 

of rainfall during the growing season (based on 

Carr, 1991). For 1990, a water-application rate 

of 0.5 (acre-ft)/yr per acre or about 446 gal/d 

per acre was used for counties on the lower 

Eastern Shore of Maryland (Dorchester, Somerset, Wicomico, and Worcester), and 0.3 (acreft)/yr per acre or about 295 gal/d per acre was 

used for counties on the upper Eastern Shore 

(Caroline, Kent, Queen Annes, and Talbot) and 

the rest of the State. Irrigation water use for 

1991 was estimated using 0.75 (acre-ft)/yr per 

acre or about 670 gal/d per acre during 1991 

(L.E. Carr, Maryland Cooperative Extension 

Service, oral commun., 1991 and 1992).

WATER USE

During 1990, approximately 1,460 Mgal/d 

of freshwater was withdrawn from surfacewater and ground-water sources in Maryland. 

Of this amount, 1,210 Mgal/d (83 percent) was

used in the State and 248 Mgal/d (17 percent) 

was transferred to surrounding States and the 

District of Columbia for water supply. About 7.5 

Mgal/d of freshwater was imported from bordering States for use in Maryland. During 1991, 

about 1,500 Mgal/d of freshwater was withdrawn. Of this amount, 1,250 Mgal/d (84 

percent) was used in the State and 249 Mgal/d 

(16 percent) was transferred to surrounding 

areas. About 6.6 Mgal/d of freshwater was 

imported from bordering States for use in Maryland. In addition, some public suppliers in 

Maryland withdraw or deliver water across 

county and State boundaries. Suppliers that 

withdraw or deliver water across county and 

State boundaries and the quantities delivered are 

shown in table 1.

Withdrawals of freshwater by county are 

shown in figure 2. The largest surface-water 

withdrawals (more than 100 Mgal/d) were in 

Baltimore and Montgomery Counties. The reservoirs and rivers in these counties provide water 

sources for public suppliers that serve the Baltimore City and District of Columbia metropolitan 

areas. The smallest withdrawals (less than 4.5 

Mgal/d) were in Howard County. The county is 

served primarily by the Baltimore City publicsupply system and the Washington Suburban 

Sanitary Commission (WSSC) system with 

water sources in Montgomery and Prince 

Georges Counties.

Freshwater withdrawals by category of use 

are summarized in figure 3. Withdrawal and use 

data by county in 1990 and 1991 are presented in 

tables 3-13 in the appendix. Table 3a summarizes 

total withdrawals by county in 1990; table 3b 

summarizes total withdrawals by county in 1991.

A comparison of total fresh surface-water 

and ground-water withdrawals by county during 1990 and 1991 is shown in figure 4. During 

each year, approximately 83 percent (1,220 

Mgal/d during 1990 and 1,250 Mgal/d during 

1991) of the freshwater withdrawn was from surface-water sources, compared to 17 percent (240 

Mgal/d during 1990 and 255 Mgal/d during 

1991) withdrawn from ground-water sources. 

Most fresh surface water (more than 100 

Mgal/d) was withdrawn in Montgomery and 

Baltimore Counties (tables 3a and 3b), whereas 

most ground water (more than 25 Mgal/d) was 

withdrawn in Anne Arundel County.

4 Water Withdrawal and Use in Maryland, 1990-91
Table I. Maryland water suppliers cross-boundary withdrawals and deliveries, 1990-91

[See fig. 1 for locations]

Water supplier County and State of withdrawal County and State of use

Amount delivered, in million gallons per day 

1990 1991

Baltimore City

Barton

Brunswick

Cumberland

Delmar

Frostburg

Baltimore, Md.

Garrett, Md.

Washington, Md.

Loudoun, Va.

Bedford, Pa.

Sussex, Del.

Garrett, Md.

Anne Arundel, Md.

Baltimore City

Carroll,Md.

Howard, Md.

Allegany, Md.

Frederick, Md.

Frederick, Md.

Allegany, Md.

Wicomico, Md.

Allegany, Md.

9.12

135.22

1.18

13.92

.09

.16

.08

7.08

.35

.84

10.00

127.19

1.27

16.43

.09

.22

.08

6.20

.35

.84

Mt. Airy Frederick, Md.

Washington Suburban

Sanitary Commision Montgomery, Md.

Prince Georges, Md.

Westernport Garrett, Md.

Fairfax County

Water Authority Montgomery, Md.

Leesburg Montgomery, Md.

Paw Paw Allegany, Md.

Piedmont Garrett, Md.

Shepherdstown Washington, Md.

Washington Aqueduct Montgomery, Md.

Carroll,Md.

Prince Georges, Md.

Howard, Md.

Allegany, Md.

Fairfax, Va.

Loudoun, Va.

Morgan, W. Va.

Mineral, W.Va.

Jefferson, W. Va.

District of Columbia

.23

42.06

3.00

.78

49.30

1.40

.04

.09

.36

196.39

.23

42.05

3.00

.76

52.88

1.68

.04

.09

.35

194.24

The largest drainage basins in Maryland are 

the Potomac and the Upper Chesapeake (fig. 5). 

During 1990 and 1991, over 70 percent of total 

fresh surface-water withdrawals were from 

streams in the Potomac Basin. During 1990, 

about 870 Mgal/d of fresh surface water was 

withdrawn and used in this basin compared to 

300 Mgal/d withdrawn and used in the Upper 

Chesapeake Basin. In addition, about 17 Mgal/d 

of fresh surface water was withdrawn in the 

Potomac Basin and transferred to the Chesapeake Basin. About 27 Mgal/d of fresh surface 

water was withdrawn in the Upper Chesapeake 

Basin and transferred to the Potomac Basin for 

use.

During 1991, about 875 Mgal/d of fresh surface water was withdrawn and used in the 

Potomac Basin compared to 318 Mgal/d withdrawn and used in the Upper Chesapeake Basin. 

In addition, about 17 Mgal/d of fresh surface 

water was withdrawn in the Potomac Basin and 

transferred to the Upper Chesapeake Basin for

use. About 31 Mgal/d of fresh surface water was 

withdrawn in the Upper Chesapeake Basin, and 

transferred to the Potomac Basin for use. Each 

year, less than 1 percent of all fresh surface water 

withdrawn was from the parts of the Monongahela, Susquehanna, and Delaware River (amount 

too small to show on graph) drainage basins in 

Maryland.

During 1990, about 71 percent (170 Mgal/d) 

of fresh ground-water was withdrawn and used 

in the Upper Chesapeake Basin, compared to 

about 27 percent (65 Mgal/d) in the Potomac 

Basin. During 1991, total ground-water withdrawals increased to 184 Mgal/d (72 percent) in 

the Upper Chesapeake Basin and remained the 

same at 65 Mgal/d (25 percent) in the Potomac 

Basin. Only about 2 percent of total groundwater withdrawals were from sites in the 

Monongahela, Susquehanna, and Delaware 

River (amount too small to show on graph) 

drainage basins.

Water Withdrawal and Use in Maryland, 1990-91 5
79' 78' 77 76' 75'

39

38'

FRESHWATER WITHDRAWALS, 

IN MILLION GALLONS PER DAY

0 to 5 

5 to 25 

25 to 100 

100 to 1,000

50 MILES

50 KILOMETERS

1990

79 78' 77 76' 75'

39

38'

FRESHWATER WITHDRAWALS, 

IN MILLION GALLONS PER DAY

0 to 5 

5 to 25 

25 to 100 

100 to 1,000

50 MILES

50 KILOMETERS 

J________________I

1991

Figure 2. Freshwater withdrawals in Maryland, by county, 1990-91.

Water Withdrawal and Use in Maryland, 1990-91
1,000

800

600

400

200

0

54.6

1990

Total Freshwater Withdrawals 

TOTAL: 1,460 Million gallons per day 

Fresh Surface-Water Withdrawals 

TOTAL: 1,220 Mgal/d. 

Fresh Ground-Water Withdrawals 

TOTAL: 240 Mgal/d.

Totals rounded to 3 

significant numbers

28.8 34.3

1 Domestic ' Industrial ' Thermoelectric Power ' Irrigation 

Public Supply Commercial Mining Livestock and Aquaculture

in

1

O

g

I

a

1,000

800 -

600 -

Total Freshwater Withdrawals 

TOTAL: 1,500 Million gallons per day 

Fresh Surface-Water Withdrawals 

TOTAL:!, 250 Mgal/d.

Fresh Ground-Water Withdrawals 

TOTAL: 255 Mgal/d.

Totals rounded to 3 

significant numbers

400 -

200 -

Domestic Industrial ' Thermoelectric Power ' Irrigation 

Public Supply Commercial Mining Livestock and Aquaculture

Number indicates percentage of water withdrawals 

by source for each category of use.

Figure 3. Freshwater withdrawals and source of water in Maryland, by category of use, 1990-91.

Water Withdrawal and Use in Maryland, 1990-91 7
79° 78° 77° 76'

39'

38'

0 50MILES 

0 ' ' ' ' 50 KILOMETERS

39'

38 (

75' 79 < 78° 77° 76'

39'

38'

1990

79° 78° 77° 76° 75' 79° 78' 77'

39'

38'

1991

75'

76° 75'

EXPLANATION

FRESHWATER WITHDRAWALS, 

IN MILLION GALLONS PER DAY

Oto5

5 to 10 

10 to 25 

25 to 100 

100 to 1,000

PERCENT OF TOTAL 

FRESHWATER WITHDRAWALS

Surface Water 

83 Percent

Ground Water 

17 Percent

Figure 4. Fresh surface-water and ground-water withdrawals in Maryland, by county, 1990-91.

8 Water Withdrawal and Use in Maryland, 1990-91
1,000

o 

§

1

72.6 Percentage of withdrawals

by Principal 

Drainage Basins

Fresh Surface-Water Withdrawals 

Total: 1,220 Million Gallons per day .

Ground-Water Withdrawals 

Total: 240 Mgal/d

Totals rounded to 

3 significant numbers

Susquehanna 

Upper Chesapeake Monongahela

Percentage of Withdrawals

by Principal 

Drainage Basins

Fresh Surface-Water Withdrawals 

Total: 1,250 Million Gallons per day _

Ground-Water Withdrawals 

Total: 255 MgaVd

Totals rounded to 

3 significant numbers

Susquehanna 

Upper Chesapeake Monongahela

1990

EXPLANATION

0.2 Number indicates percentage of 

withdrawals by drainage basins

1991

BOUNDARY

Principal Drainage Basins 

in Maryland

38 o

Figure 5. Fresh surface-water and ground-water withdrawals in Maryland, by principal drainage basin, 1990-91.

Water Withdrawal and Use in Maryland, 1990-91 9
Estimated percentages of ground-water 

withdrawals by principal aquifers during 1990 

and 1991 are shown in figure 6. The map and 

hydrogeologic section show the geographic distribution of the principal aquifers in Maryland 

(U.S. Geological Survey, 1990, p. 294). The Potomac Group aquifers were the largest source of 

ground water with 64 Mgal/d withdrawn during 1990 and 68 Mgal/d during 1991 (26.6 

percent of total ground-water withdrawals), followed by the Columbia and Piedmont aquifers 

with about 36 Mgal/d during 1990 and 38 

Mgal/d during 1991 (about 15 percent). The 

smallest amount of water was withdrawn from 

the Newark Group aquifers with about 2 

Mgal/d withdrawn each year (0.9 percent).

Population and Water-Use Trends

The population of Maryland increased from 

4,780,000 during 1990 (U.S Department of Commerce, 1990a) to 4,830,000 in 1991 (estimates 

based on projections from Maryland Department 

of State Planning, 1990). Population and wateruse data for 1990 and 1991 are presented in table 

2. The population served by public water-supply 

systems increased from 3.94 million during 1990 

to 3.97 million during 1991. During each year, 

surface water was used by about 69 percent of 

the population and ground water was used by 31 

percent of the population.

Population and water-use trends in Maryland from 1950 to 1991 are shown in figure 7. 

During 1950, about 2.34 million people used 

approximately 400 Mgal/d of freshwater. Population and water use increased steadily through 

the 1950's and 1960's. Subsequently, however, 

population growth slowed, increasing from 3.92 

million people in 1970 to 4.83 million in 1991. 

Water use during the same period leveled off in 

the early 1970's at about 1,500 Mgal/d, then 

decreased over the rest of the decade. During 

1980, water use was about 1,400 Mgal/d. Possible explanations for the decrease in water use 

include changing economic conditions, declining 

water use among certain industries, and increasing use of conservation techniques and fixtures. 

However, freshwater use increased overall from 

1985 to 1991, from about 1,400 Mgal/d to about 

1,500 Mgal/d, primarily because of increased 

withdrawals for cooling purposes by power 

plants, and for irrigation and public-supply distribution.

Public Supply

The largest amount of water withdrawn in 

the State, 798 Mgal/d during 1990 and 826 

Mgal/d during 1991 (55 percent of total freshwater withdrawals; fig. 3), was by public-supply 

systems operated by municipalities, counties 

and towns, and private utilities. Public suppliers delivered water to 82 percent of the total 

population during both 1990 and 1991 (table 2). 

Water was delivered for a variety of uses including domestic, commercial, and industrial uses 

(tables 4a and 4b). In addition, each year during 

the peak tourist season (May through September), the Ocean City water-supply system in 

Worcester County served about 268,000 more 

people than the base population of about 12,000 

(Andrews, Miller & Assoc., Inc., 1990, p. 2-9).

Most public suppliers in central and western 

Maryland rely on surface-water sources. Some 

of these suppliers withdraw and deliver water 

across county and State boundaries as shown in 

table 1. The largest user of surface water for public supply is Baltimore City. During 1990, about 

135 Mgal/d was withdrawn for use by the city 

compared to about 127 Mgal/d during 1991. In 

addition, Baltimore City supplied about 127 

Mgal/d during 1990 and 121 Mgal/d during 

1991 to parts of Baltimore, Howard, Anne Arundel, and Carroll Counties. Another large user of 

surface water for public supply in Maryland is 

the WSSC, which withdrew 174 Mgal/d during 

1990 and 180 Mgal/d during 1991 and delivered 

water to most of Montgomery and Prince 

Georges Counties and part of Howard County.

The Potomac River in Maryland is a water 

source for several public suppliers in Virginia 

and West Virginia and for the U.S. Army Corps 

of Engineers, who delivers water to the District 

of Columbia through the Washington Aqueduct. 

During 1990, about 50.7 Mgal/d of fresh surface 

water was withdrawn from the river and transferred to Virginia and West Virginia for use, 

compared to 54.6 Mgal/d withdrawn and transferred during 1991. During 1990, the Washington Aqueduct conveyed about 196 Mgal/d from 

the Potomac River for public-supply deliveries to 

the District, compared to 194 Mgal/d conveyed 

during 1991.

10 Water Withdrawal and Use in Maryland, 1990-91
Several municipalities in Maryland 

obtained all or part of their water supply from 

bordering States during 1990 and 1991, including 

Cumberland in Allegany County, which 

received 7.08 Mgal/d of surface-water during

1990 (6.20 Mgal/d during 1991) from two impoundments on Evitts Creek in Bedford County, 

Pennsylvania; Brunswick in Frederick County, 

which received about 0.08 Mgal/d each year 

from springs in Loudoun County, Virginia; and 

Delmar in Wicomico County, which received 

0.35 Mgal/d each year from wells in Sussex 

County, Delaware.

Most public suppliers that rely on groundwater sources are in the eastern and southern 

parts of Maryland. In counties east of Chesapeake Bay, all public suppliers rely on ground 

water. The largest ground-water withdrawals 

for public supply, however, are in Anne Arundel 

County. During 1990, about 26 Mgal/d was 

withdrawn by public suppliers in the county 

compared to 27.8 Mgal/d during 1991.

Domestic

Domestic users in Maryland receive water 

from public-supply systems and from self-supplied sources (tables 5a and 5b). During 1990, 

total use (withdrawals plus deliveries) was 484 

Mgal/d, of which 414 Mgal/d was delivered by 

public suppliers. Eighteen percent of the total 

population (843,000 people) withdrew about 69.9 

Mgal/d from privately owned wells (self-supplied). Domestic water use increased during

1991 to 490 Mgal/d, of which 420 Mgal/d was 

delivered by public suppliers. As in 1990,18 percent of the total population (860,000 people) 

withdrew about 71.4 Mgal/d from self-supplied 

sources. All self-supplied water withdrawn for 

domestic use was assumed to be from ground 

water.

Commercial

Commercial users, including educational 

institutions and military installations, receive 

water from public-supply systems and from privately owned wells. Total commercial use 

during 1990 was 113 Mgal/d (table 6a), of which 

about 87.1 Mgal/d (77 percent) was provided by 

public suppliers and about 25.8 Mgal/d (23 percent) was self-supplied. During 1991, total 

commercial use was 112 Mgal/d (table 6b), of

which about 86.8 Mgal/d (78 percent) was provided by public suppliers and about 25.1 

Mgal/d (22 percent) was self-supplied.

Industrial

Maryland is located within a regional manufacturing belt that extends along the eastern 

seaboard of the United States. Heavy and light 

industries are important to the State's economy. 

Heavy industries include steel, chemical and 

allied products, shipbuilding, petroleum refining, and truck-assembly. Prominent light 

industries include food processing, printing, 

publishing, and clothing manufacturing. Water 

used by industries is from self-supplied and public-supply systems. Major water uses include 

washing and separation, cooling of industrial 

machinery, refrigeration, boiler make-up, product manufacturing, and dust control.

During 1990, about 123 Mgal/d of freshwater was used by industries in Maryland (table 

7a). Of that amount, 70.1 Mgal/d or 57 percent 

was self-supplied and 52.4 Mgal/d (43 percent) 

was provided by public suppliers. Industries 

used less water during 1991, about 116 Mgal/d 

(table 7b), of which 67.2 Mgal/d (58 percent) was 

self-supplied and 49.2 Mgal/d (42 percent) was 

provided by public suppliers. Industries also 

used 379 Mgal/d during 1990 and 312 Mgal/d 

during 1991 of brackish or saline surface water. 

About 62.5 Mgal/d of reclaimed wastewater 

was used each year in steel production primarily 

for two types of purposes. The first is noncontact cooling that is, the water is used for heat 

exchange such as in the cooling of machinery or 

furnace structures. The second is contact cooling 

and cleaning of steel in the production process. 

Some reclaimed wastewater is also treated then 

recycled.

Industries in Allegany County had the largest fresh surface-water withdrawals during both 

years (45.06 Mgal/d in 1990 and 44.99 Mgal/d in 

1991). Baltimore County had the largest salinesurface water withdrawals-372.6 Mgal/d (1990) 

and 304.8 Mgal/d (1991), as well as the largest 

reclaimed wastewater use (62.5 Mgal/d) for the 

period. The largest ground-water withdrawals 

for industrial use for both years were in Baltimore City with 4.52 Mgal/d in 1990 and 4.68 

Mgal/d in 1991.

Water Withdrawal and Use in Maryland, 1990-91 11
O 

§

I

(A) Withdrawals By Aquifers

4 NUMBER IS PERCENTAGE 

OF TOTAL GROUND-WATER 

WITHDRAWALS BY AQUIFER.

Chesapeake

Group 

Columbia Piney Point

Potomac 

Group

Magothy Piedmont & 

Blue Ridge 

Crystalline

Newark 

Group 

Appalachian 

Sedimentary

(B) Hydrogeologic Section (C) Aquifers

Hydrogeologic 

Section

Atlantic 

Ocean

Principal aquifers shown in hydrogeologic section

Piedmont and Blue Ridge crystalline (1)

Potomac Group (2)

Magothy (3)

Not a principal aquifer (4)

Aquia (5)

PlneyPoint(6)

Cheasapeake Group (7)

Columbia (8)

FEET 1.000 (

SEA. 

LEVEL

-1.000-

-2.000

Chesapeake Bay Atlantic Ocean

Piedmont and 

Blue Ridge 

Crystalline

NOT TO SCALE

0 50 MILES li'irVi ' '

0 50 KILOMETERS

Figure 6. Ground-water withdrawals in Maryland, by principal aquifers, 1990-91. (A) Withdrawals by aquifer. 

(B) Trace of generalized hydrologic section (A-A'). (O Geographic distribution of use for principal 

aquifers.

12 Water Withdrawal and Use in Maryland, 1990-91
AQUIFERS

0 50 MILES

ll'lM"

0 50 KILOMETERS

Chesapeake Group Potomac Group

Piney Point Appalachian 

Sedimentary

Aquia

Figure 6. Ground-water withdrawals in Maryland, by principal aquifers, 1990-91. Continued

Water Withdrawal and Use in Maryland, 1990-91 13
Table 2.-Population and water use in Maryland, 1990-91

[Population data rounded to three significant figures and may not add to totals because of independent 

rounding. Percentages rounded to two significant figures]

1990

1

CO

$ 

o

§

3,000

2,500

2,000

1,500

3 1,000

I

D 500

0

POPULATION

1991

Total population:

Population served by public-supply systems

Percentage of population served

Population served by self-supplied systems

Percentage of population self-supplied

Surface-water supply:

Percentage of total population served by surface water

Number served by public-supply systems

Percentage of total population

Number served by self-supplied systems

Percentage of total population

Ground-water supply:

Percentage of total population served by ground water 

Number served by public-supply systems

Percentage of total population

Number served by self-supplied systems

Percentage of total population

4,780,000

3,940,000

82

843,000

18

69

3,290,000

69

0

0

31 

645,000

13

843,000

18

4,830,000

3,970,000

82

860,000

18

69

3,310,000

69

0

0

31

657,000

14

860,000

18

1955 1960 1965 1970 1975 1980 1985 1986 1987 1988 1989 1990 1991

(Trends between data points are inferred)

5

4.5

4

3.5

3

2.5

2

1.5

1

.5

0

Sources: MacKichan, 1951; MacKichan and Kammerer, 1957; MacKichan and Kammerer, 1961; Murray, 1968; Murray and Reeves, 

1972; Murray and Reeves, 1977; Solley and others, 1983; Solley and others, 1988; Solley and others, 1993; Maryland W ater 

Resources Administration water-use data base; and data compiled from the Maryland Department of State Planning.

Figure 7. Population and freshwater withdrawals in Maryland, 1950-91.

14 Water Withdrawal and Use in Maryland, 1990-91
Mining

Mining is a major economic activity in 

Maryland. The mineral resources extracted are 

those primarily used for building materials and 

fuels and include stone, sand, gravel, and bituminous coal. Water withdrawn in mining 

operations is primarily used for dewatering and 

washing. During 1990,28 Mgal/d of freshwater 

was withdrawn for mining purposes (table 8a). 

Of that amount, 7.50 Mgal/d was from surfacewater sources and 20.5 Mgal/d was from 

ground-water sources. An additional 21.3 

Mgal/d of brackish or saline surface water was 

withdrawn, of which about 20.6 Mgal/d was for 

dredging operations. Total freshwater withdrawals for mining during 1991 were 25.3 

Mgal/d (table 8b). Of that amount, 7.76 Mgal/d 

was from surface-water sources and 17.5 Mgal/d 

was from ground-water sources. Brackish or 

saline surface-water withdrawals decreased 82 

percent in 1991 to 3.77 Mgal/d due mainly to 

reduced dredging operations.

Thermoelectric Power

Fourteen thermoelectric power plants operate in Maryland; 13 are fossil-fueled and 1 is 

nuclear-fueled. The demand for electricity and 

consequently, the amount of water used by 

power plants, is influenced by various economic, 

demographic and technological factors such as 

appliance holdings, weather, household size, 

income, and the price of electricity. In general, 

electricity demand is expected to increase in 

Maryland (Maryland Power Plant Research Program, 1993).

Freshwater use by power plants during 1990 

was 421 Mgal/d, of which about 419 Mgal/d was 

from surface-water sources and 1.85 Mgal/d was 

from ground-water sources (table 9a). In addition, 4,550 Mgal/d of saline surface water was 

used by the plants for cooling condensers, of 

which more than 98 percent was returned to the 

water source. During 1991, thermoelectric 

power plants used about 416 Mgal/d of freshwater, of which about 414 Mgal/d was from surface-water sources and 1.65 Mgal/d was from 

ground-water sources (table 9b). Larger quantities of saline surface water (5,760 Mgal/d) were 

used for cooling condensers during 1991 than in 

1990.

Hydroelectric Power

Water used for the generation of electricity 

by hydroelectric power plants is discussed here 

but the quantities of water used are not included 

in the freshwater totals because this use is considered an "instream" water use that is, water 

use takes place within the stream channel at the 

dam, where turbine generators are driven by the 

falling water. Twelve plants are currently producing or are licensed to produce hydroelectric 

power in Maryland (Weisberg and Rose, 1985, p. 

1), the largest of which is in Harford County.

During 1990, about 25,900 Mgal/d of freshwater passed through these plants for the production of electricity (table lOa); during 1991, the 

amount decreased to 21,900 Mgal/d (table lOb). 

Although the amount of water diverted through 

some plants is considerable, consumptive use is 

negligible, because water is not withdrawn from 

the stream or incorporated into a product. Any 

consumption is by evaporation during the generation process and from storage reservoirs and 

this quantity is unknown.

Livestock

During 1990 and 1991, an estimated 10.4 

Mgal/d of freshwater was used for livestock 

activities, mainly livestock watering and feedlot 

and dairy operations; 2.44 Mgal/d was from surface-water sources and 7.95 Mgal/d was from 

ground-water sources (table 11). The major 

types of livestock raised in Maryland are poultry, 

cattle, dairy cows, hogs, and sheep. The four 

counties (Dorchester, Somerset, Wicomico, and 

Worcester) of the lower Eastern Shore account 

for about 30 percent of total agricultural revenue 

in the State, because this area is one of the 

Nation's leading producers of broiler chickens 

(Maryland Department of Agriculture, 1990b).

Irrigation

The amount of water used for irrigation can 

vary greatly by year and among users during a 

particular year. In addition to differences in 

soils and rainfall distribution, other factors 

including type of crop or turf grown, timing and 

length of planting and growing seasons, and 

watering schedule affect the amount of water 

used for irrigation (Brodie and others, 1984, p. 7).

Water Withdrawal and Use in Maryland, 1990-91 15
Freshwater use for irrigating farm crops; 

commercial, municipal, and institutional lawns 

and parks; golf courses; and nursery plants was 

about 29.1 Mgal/d during 1990 (table 12a). Of 

this amount, 22.8 Mgal/d was used for irrigating 

crops including corn, soybeans, tobacco, grains, 

tomatoes, and melons. In addition, 2.20 Mgal/d 

of brackish surface water was used for farm irrigation. Brackish water is too saline to be potable, 

but is less saline than seawater that is, total dissolved solids (TDS) concentrations range from 

about 1,000 to 20,000 mg/L; the TDS concentrations in seawater are about 35,000 mg/L (Drever, 

1982, p. 12).

About 70,000 acres of cropland in Maryland 

were irrigated in the State during 1990, of which 

about 63,500 acres or 90 percent were in the eight 

counties east of Chesapeake Bay (fig. 1). During 

1990, about 9.95 Mgal/d of fresh surface water 

was used to irrigate about 24,700 acres and 19.2 

Mgal/d of ground water was used to irrigate 

about 38,900 acres.

During 1991, total freshwater used for irrigation increased to 50.4 Mgal/d (table 12b), of 

which 41.1 Mgal/d was used for irrigating farm 

crops. More land (about 71,700 acres) was irrigated during 1991 than during 1990. About 17.5 

Mgal/d of fresh surface water was used to irrigate about 25,100 acres and 32.8 Mgal/d of fresh 

ground water was used to irrigate about 39,600 

acres. In addition, about 4.78 Mgal/d of brackish surface water was used for irrigating crops.

The county with the largest total irrigated 

acreage in the State was Caroline County-19,700 

acres during 1990 and 20,100 acres during 1991 

(about 28 percent of total irrigated land). The 

largest freshwater withdrawals for irrigation 

were in Dorchester County, with 7.86 Mgal/d 

during 1990 and 12.05 Mgal/d during 1991.

Aquaculture

Aquaculture, also known as fish farming or 

fish culture, is the controlled production of finfish, shellfish, and aquatic plants in fresh and 

saline water (Maryland Department of Agriculture, 1990a). In Maryland, aquaculture includes 

production of ornamental fish, oysters, soft-shell 

crabs, crawfish, hybrid striped bass, catfish, tilapia, trout, aquatic plants, and other aquatic 

species such as perch and sturgeon.

During 1990, about 9.37 Mgal/d of freshwater was withdrawn for aquaculture in the 

State, of which 4.84 Mgal/d was from surfacewater sources and 4.53 Mgal/d was from 

ground-water sources (table 13a). In addition, 

9.58 Mgal/d of saline surface water was used for 

this purpose. Freshwater withdrawals for aquaculture increased during 1991 to 11.6 Mgal/d, of 

which 6.56 Mgal/d was from surface-water 

sources and 5.00 Mgal/d was from groundwater sources (table 13b). Use of saline surface 

water also increased during 1991 to 12.5 Mgal/d.

SUMMARY

During 1990, about 1,460 Mgal/d of freshwater was withdrawn from surface-water and 

ground-water sources in Maryland, compared to 

about 1,500 Mgal/d withdrawn during 1991. 

About 1,210 Mgal/d (83 percent) during 1990 

and 1,250 Mgal/d (84 percent) during 1991 were 

used in the State. About 248 Mgal/d (17 percent) 

during 1990 and 249 Mgal/d (16 percent) during 

1991 were transferred to surrounding States and 

the District of Columbia for water supply. About 

7.5 Mgal/d of freshwater during 1990 and 6.6 

Mgal/d during 1991 were imported from bordering States for use in Maryland.

Most freshwater withdrawals (about 1,220 

Mgal/d during 1990 and 1,250 Mgal/d during 

1991 or 83 percent of total freshwater withdrawals) were from surface-water sources. The 

largest surface-water withdrawals, more than 

100 Mgal/d, were in Montgomery and Baltimore 

Counties. The reservoirs and rivers in these 

counties provide water sources for public suppliers that serve the Baltimore City and District of 

Columbia metropolitan areas. Most fresh surface water (about 870 Mgal/d during 1990 and 

875 Mgal/d during 1991 or more than 70 percent 

of total surface-water withdrawals) was withdrawn and used in the Potomac drainage basin, 

whereas most ground water (about 170 Mgal/d 

during 1990 and 184 Mgal/d during 1991) was 

withdrawn and used in the Upper Chesapeake 

drainage basin. The Potomac Group aquifers 

were the largest source of ground water (26.6 

percent of total ground-water withdrawals) each 

year.

The population of Maryland served by public water-supply systems increased slightly from 

3.94 million during 1990 to 3.97 million during

16 Water Withdrawal and Use in Maryland, 1990-91
1991 (82 percent of the total population). In 

addition, during the peak tourist season (from 

May to September), the Ocean City water-supply 

system served approximately 268,000 more individuals than the base population of about 12,000. 

During 1990-91, surface water was used by about 

69 percent of the State's population and ground 

water was used by the remaining 31 percent.

Ten water-use categories represent the 

major demands on the surface-water and 

ground-water resources of the State during 1990- 

91: Public supply, domestic, commercial, industrial, mining, thermoelectric power, hydroelectric power, livestock, irrigation, and aquaculture. Freshwater withdrawals for public supply, 

self-supplied domestic use, aquaculture, and irrigation increased during 1990-91, whereas withdrawals for commercial, industrial, thermo-electric power, and mining uses decreased.

Public-supply systems withdrew the largest 

quantity of water in the State (798 Mgal/d during 1990 and 826 Mgal/d during 1991) during 

1990-91. This water was delivered for a variety 

of uses including domestic, commercial, and 

industrial uses. The largest user of surface water 

for public supply was Baltimore City. During 

1990, about 135 Mgal/d was withdrawn for use 

by the City compared to about 127 Mgal/d during 1991.

Domestic water use increased from about 

484 Mgal/d during 1990 to 490 Mgal/d during 

1991. About 414 Mgal/d during 1990 and 420 

Mgal/d during 1991 were received from public 

suppliers and about 69.9 Mgal/d during 1990 

and 71.4Mgal/d during 1991 were self-supplied. 

All self-supplied domestic water withdrawals 

were from ground-water sources.

Total commercial use during 1990 was 113 

Mgal/d, of which about 87.1 Mgal/d was provided by public suppliers and about 25.8 

Mgal/d was self-supplied. During 1991, total 

commercial use decreased to 112 Mgal/d, of 

which about 86.8 Mgal/d was provided by public suppliers and about 25.1 Mgal/d was selfsupplied.

Fresh surface-water and ground-water use 

by industries decreased from 123 Mgal/d during

1990 to 116 Mgal/d during 1991. About 70.1 

Mgal/d during 1990 and 67.2 Mgal/d during

1991 were self-supplied. The remaining water 

used was delivered by public suppliers. Industries also used saline surface water-379 Mgal/d 

duringl990and312Mgal/dduringl991. About 

62.5 Mgal/d of reclaimed wastewater was used 

for industrial purposes each year.

Fresh surface-water and ground-water use 

for mining decreased from 28 Mgal/d during

1990 to 25.3 Mgal/d during 1991. About 21.3 

Mgal/d during 1990 and 3.77 Mgal/d during

1991 of brackish or saline surface water were 

withdrawn, primarily for dredging operations.

Fresh surface-water and ground-water 

withdrawals for thermoelectric power decreased 

from 421 Mgal/d during 1990 to 416 Mgal/d 

during 1991. Larger quantities of saline surface 

water were used for cooling purposes during 

1991 (5,760 Mgal/d) than during 1990 (4,550 

Mgal/d).

Fresh surface-water use for hydroelectric 

power decreased from 25,900 Mgal/d during 

1990 to 21,900 Mgal/d during 1991. Although 

the amount of water diverted through some 

plants was considerable, the amount consumed 

was negligible.

Fresh surface-water and ground-water use 

for livestock was about 10.4 Mgal/d during each 

year of the 2-year period. About 2.44 Mgal/d 

was from surface-water sources and 7.95 Mgal/d 

was from ground-water sources.

Fresh surface-water and ground-water use 

for irrigation increased from 29.1 Mgal/d during 

1990 to 50.4 Mgal/d during 1991. Most of the 

water (22.8 Mgal/d during 1990 and 41.1 

Mgal/d during 1991) was used for irrigating 

farm crops.

Fresh surface-water and ground-water 

withdrawals for aquaculture increased from 9.37 

Mgal/d during!990 to 11.6 Mgal/d during!991. 

Saline surface-water withdrawals for aquaculture also increased from 9.58 Mgal/d during 

1990 to 12.5 Mgal/d during 1991.

Water Withdrawal and Use in Maryland, 1990-91 17
SELECTED REFERENCES

Andrews, Miller & Assoc., Inc., 1990, Comprehensive

water & sewerage plan for Worcester County,

Maryland: Andrews, Miller & Assoc., Inc.,

Cambridge, Maryland, 166 p. 

Booth, Nan, 1984, Maryland residential water statistics:

University of Maryland, Cooperative Extension

Service Fact Sheet 383, College Park, Maryland, 2 p. 

Brodie, H.L., Carr, L.E., Russek, Estelle, and

Stewart, L.E., 1984, A survey of agricultural

irrigation in Maryland-1982: University of

Maryland, Cooperative Extension Service, College

Park, Maryland, 51 p. 

Carr, L.E., 1991, The 1990 Maryland irrigation survey:

University of Maryland, College Park, Maryland, 7 p. 

Drever, J.I., 1982, The geochemistry of natural waters:

Prentice-Hall, Inc., Englewood Cliffs, New Jersey,

388 p. 

Di Lisio, J.E., 1983, Maryland, a geography: Boulder,

Colorado, Westview Press, 233 p. 

Hem, J.D., 1985, Study and interpretation of the

chemical characteristics of natural water: U.S.

Geological Survey Water-Supply Paper 2254,263 p. 

MacKichan, K.A., 1951, Estimated use of water in the

United States-1950: U.S. Geological Survey Circular

115, 13 p. 

MacKichan, K.A., and Kammerer, J.C., 1957,

Estimated use of water in the United States, 1955:

U.S. Geological Survey Circular 398,18 p. 

___1961, Estimated use of water in the United States

in 1960: U.S. Geological Survey Circular 456,44 p. 

Maryland Department of Agriculture, 1990a,

Aquaculture in Maryland: Information Sheet,

Annapolis, Maryland, 2 p. 

___1990b, Maryland agricultural statistics-Summary

for 1990: Maryland Department of Agriculture,

Annapolis, Maryland, 53 p. 

Maryland Department of State Planning, 1981,

Maryland population data-State, county, minor civil

division and municipal trends through 1980:

Maryland Department of State Planning, Office of

Planning Data, Baltimore, Maryland, 253 p. 

___1990, Maryland Office of Planning population

projections: Maryland Department of State Planning,

Office of Planning, Report 5A-Total (Revisions, June

1990), Baltimore, Maryland, 75 p. 

Maryland Water Resources Administration, 1987,

Maryland water withdrawal and use report for 1985:

Maryland Department of Natural Resources,

Annapolis, Maryland, 40 p.

Murray, C.R., 1968, Estimated use of water in the 

United States in 1965: U.S. Geological Survey 

Circular 556,53 p.

Murray, C.R., and Reeves, E.B., 1972, Estimated use 

of water in the United States in 1970: U.S. 

Geological Survey Circular 675,37 p.

___1977, Estimated use of water in the United States 

in 1975: U.S. Geological Survey Circular 765,39 p.

Maryland Power Plant Research Program, 1993, 

Maryland power plants and the environment; a 

review of impacts of power plants and transmission 

lines on Maryland's natural resources; supporting 

materials: Maryland Department of Natural 

Resources, Annapolis, Maryland, 75 p.

Solley, W.B., Chase, E.B., and Mann, W.B., 1983, 

Estimated use of water in the United States in 1980: 

U.S. Geological Survey Circular 1001,82 p.

Solley, W.B., Merk, C.F., and Pierce, R.R., 1988, 

Estimated use of water in the United States in 1985: 

U.S. Geological Survey Circular 1004, 82 p.

Solley, W.B., Pierce, R.R., and Permian, H.A., 1993, 

Estimated use of water in the United States in 1990: 

U.S. Geological Survey Circular 1081,76 p.

U.S. Department of Commerce, 1988, 1987 census of 

agriculture, advance county reports: U.S. Bureau of 

the Census, Government Printing Office, Washington, D.C., (23) 2-page sheets, by county.

___1990a, 1990 census of population and housing-- 

Summary population and housing characteristics-- 

Maryland: U.S. Bureau of the Census, Government 

Printing Office, 1990 CPH-1-22,117 p. 

_1990b, 1990 census of population and housingSummary social, economic, and housing 

characteristics-Maryland: U.S. Bureau of the 

Census, Government Printing Office, 1990 CPH-5- 

22,155 p.

U.S. Environmental Protection Agency, 1973, Manual 

of individual water supply systems: U.S. Government Printing Office, Washington, D.C., 155 p.

U.S. Geological Survey, 1985, National water summary 

1984-hydrologic events, selected water-quality 

trends, and ground-water resources: U.S. Geological 

Survey Water-Supply Paper 2275,467 p.

___ 1990, National water summary 1987-hydrologic 

events and water supply and use: U.S. Geological 

Survey Water-Supply Paper 2350,553 p.

18 Water Withdrawal and Use in Maryland, 1990-91
Webb, WJE., and Heidel, S.G., 1970, Extent of 

brackish water in the tidal rivers of Maryland: 

Maryland Geological Survey Report of 

Investigations No. 13, Maryland Geological Survey, 

Baltimore, Maryland, 46 p.

Weisberg, S.B., and Rose, K.A., 1985, Inventory of 

Maryland dams and assessment of hydropower 

resources: Martin Marietta Environmental Systems, 

Columbia, Maryland, 341 p.

Wheeler, J.C., 1990, Water withdrawal and use in 

Maryland, 1986: U.S. Geological Survey Open-File 

Report 88-714,30 p.

_1991, Water withdrawal and use in Maryland,

1987: U.S. Geological Survey Open-File Report 90- 

572, 32 p. 

_1992, Water withdrawal and use in Maryland,

1988-89: U.S. Geological Survey Water-Resources 

Report of Investigations 91-4179,40 p. 

Wheeler, J.C., and Wilde, F.D., 1989, Ground-water 

use in the Coastal Plain of Maryland, 1900-1980: 

U.S. Geological Survey Open-File Report 87-540, 

173 p.

Water Withdrawal and Use in Maryland, 1990-91 19
20 Water Withdrawal and Use in Maryland, 1990-91
APPENDIX 

WATER WITHDRAWAL AND USE DATA FOR MARYLAND, 1990-91

Water Withdrawal and Use in Maryland, 1990-91 21
Table 3&.-Total water withdrawals (excluding hydroelectric power) in Maryland, by 

f

5-

I

[State totals rounded to three significant figures. (Sources: Withdrawals, data compiled from Maryland Water Resources Admi

U.S. Geological Survey site-specific data bases, and the University of Maryland Cooperative Extension Service; Population 

projections, data compiled from Maryland Department of State Planning, 1990]

Water withdrawals, in million gallons per day 

Source

Surface water Ground water Total e

5"

f 

§ 

PCounty 

or city

AUegany

Anne Arundel

Baltimore

Calvert

Caroline

Carroll

Cecil

Charles

Dorchester

Frederick

Garrett

Harford

Howard

Kent

Montgomery

Prince Georges

Queen Annes

St. Marys

Somerset

Talbot

Washington

Wicomico

Worcester

Baltimore City

State Total

Population, 

in 

thousands

74.95

427.24

692.13

51.37

27.03

123.37

71.35

101.15

30.24

150.21

28.14

182.13

187.33

17.84

757.03

729.27

33.95

75.97

23.44

30.55

121.39

74.34

35.03

736.01

4,780

Fresh

45.77

5.06

267.13

.19

2.35

4.50

3.24

.27

2.22

13.34

5.83

8.75

.42

.08

764.99

37.63

1.51

.54

.16

.36

56.12

.59

.61

.01

1,220

Saline

0.00

772.97

1,055.23

1,127.77

.00

.00

.00

1,196.27

1.46

.00

.00

.00

.00

.00

.00

615.15

.00

.01

.00

.01

.00

.00

.64

182.65

4,950

Total

45.77

778.03

1,322.36

1,127.96

2.35

4.50

3.24

1,196.54

3.68

13.34

5.83

8.75

.42

.08

764.99

652.78

1.51

.55

.16

.37

56.12

.59

1.25

182.66

6,170

Fresh

1.73

44.87

13.82

4.96

6.73

10.83

6.49

12.87

12.22

18.02

8.49

11.93

2.49

4.60

4.14

7.57

6.21

7.89

4.44

5.24

9.86

16.32

12.51

5.92

240

Saline

0.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

0.00

Total

1.73

44.87

13.82

4.96

6.73

10.83

6.49

12.87

12.22

18.02

8.49

11.93

2.49

4.60

4.14

7.57

6.21

7.89

4.44

5.24

9.86

16.32

12.51

5.92

240

Reclaimed 

wastewater

0.00

.00

62.50

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

62.5

Fresh

47.50

49.93

280.95

5.15

9.08

15.33

9.73

13.14

14.44

31.36

14.32

20.68

2.91

4.68

769.13

45.20

7.72

8.52

4.60

5.60

65.98

16.91

13.12

5.93

1,460
Table 3b.~Total water withdrawals (excluding hydroelectric power) in Maryland, by 

[State totals rounded to three significant figures. (Sources: Withdrawals, data compiled from Maryland Water Resources Admini

U.S. Geological Survey site-specific data bases, and the University of Maryland Cooperative Extension Service; Population 

projections, data compiled from Maryland Department of State Planning, 1990]

if

I

a

sf 3"

ET 

g.

Water withdrawals.

County

or city

Allegany

Anne Arundel

Baltimore

Calvert

Caroline

Carroll

Cecil

Charles

Dorchester

Frederick

Garrett

Harford

Howard

Kent

Montgomery

Prince Georges

Queen Annes

St Marys

Somerset

Talbot

Washington

Wicomico

Worcester

Baltimore City

State Total

Population,

in

thousands

74.98

431.67

694.15

53.35

27.27

127.43

72.64

104.47

30.26

154.42

28.32

185.31

192.84

17.86

769.51

735.08

35.01

77.19

23.75

30.85

121.80

75.10

35.69

732.32

4,830

Source

Surface water

Fresh

45.75

4.67

276.46

.19

5.06

4.15

3.20

.27

2.93

13.92

6.41

8.97

.51

.32

735.98

43.46

3.58

.57

.23

.79

88.61

.90

1.12

.01

1,250

Saline

0.00

991.94

603.50

2,607.12

.00

.00

.00

1,166.63

1.11

.00

.00

.00

.00

.00

.00

582.04

.00

.00

.96

.01

.00

.00

.67

118.73

6,070

Total

45.75

996.61

879.96

2,607.31

5.06

4.15

3.20

1,166.90

4.04

13.92

6.41

8.97

.51

.32

735.98

625.50

3.58

.57

1.19

.80

88.61

.90

1.79

118.74

7,320

Fresh

1.73

47.36

11.55

5.27

10.40

11.30

6.59

12.30

15.42

17.05

8.33

12.17

2.58

5.87

4.65

7.14

9.00

8.41

4.89

5.66

10.56

17.22

13.08

6.17

255

In million gallons per day

Ground water

Saline

0.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

0.00

Total

1.73

47.36

11.55

5.27

10.40

11.30

6.59

12.30

15.42

17.05

8.33

12.17

258

5.87

4.65

7.14

9.00

8.41

4.89

5.66

10.56

17.22

13.08

6.17

255

Reclaimed

wastewater

0.00

.00

62.50

.00

.00

.04

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

62.50

Total e

Fresh

47.48

52.03

288.01

5.46

15.46

15.45

9.79

12.57

18.35

30.97

14.74

21.14

3.09

6.19

740.63

50.60

12.58

8.98

5.12

6.45

99.17

18.12

14.20

6.18

1,500
Table 4a.~Public-supply water withdrawals and deliveries in Maryland, by coun

[State totals rounded to three significant figures. (Sources: Withdrawals, data compiled from Maryland Water Resources A

U.S. Geological Survey site-specific data bases; Population projections, data compiled from Maryland Department of Stat

E?91

I

I

C

s

9

2

Population served, in thousands

Water withdrawals, in million 

gallons per day

Water deliveries, by type of use, 

in million gallons per day

Source

County 

or city

Allegany

Anne Arundel

Baltimore

Calvert

Caroline

Carroll

Cecil

Charles

Dorchester

Frederick

Garrett

Harford

Howard

Kent

Montgomery

Prince Georges

Queen Annes

St. Marys

Somerset

Talbot

Washington

Wicomico

Worcester

Baltimore City

Surface 

water

58.51

80.79

635.76

.00

.00

24.51

15.58

.00

.00

56.08

4.84

31.68

161.10

.00

722.89

686.77

.00

.00

.00

.00

79.32

.00

.00

736.01

Ground 

water

2.20

235.37

1.00

14.38

9.73

10.03

10.82

63.72

15.42

26.54

1.91

84.88

.00

7.67

3.86

27.91

5.09

28.11

9.84

14.05

8.08

35.68

28.37

.00

Total

60.71

316.16

636.76

14.38

9.73

34.54

26.40

63.72

15.42

82.62

6.75

116.56

161.10

7.67

726.75

714.68

5.09

28.11

9.84

14.05

87.40

35.68

28.37

736.01

Source

Surface 

water

0.52

2.75

266.45

.00

.00

3.59

2.21

.00

.00

8.14

2.21

4.77

.00

.00

386.60

34.32

.00

.00

.00

.00

10.68

.00

.00

.00

Ground 

water

0.35

26.03

.03

1.32

1.18

1.31

1.24

6.28

3.04

2.49

.64

5.47

.00

1.11

.36

2.74

.60

2.45

1.56

2.19

1.18

6.58

7.68

.00

Total

0.87

28.78

266.48

1.32

1.18

4.90

3.45

6.28

3.04

10.63

2.85

10.24

.00

1.11

386.96

37.06

.60

2.45

1.56

2.19

11.86

6.58

7.68

.00

Domestic

7.05

30.33

71.83

1.19

1.07

5.48

2.86

5.66

1.83

8.70

.84

8.71

14.86

1.01

74.13

64.70

.48

2.21

1.40

1.86

8.51

4.85

6.53

87.89

Commercial

0.97

5.69

15.39

.13

.06

.30

.21

.62

.45

1.09

.11

1.02

1.70

.05

21.45

7.61

.06

.24

.08

.22

1.13

.69

.77

27.04

Industr

1.6

1.8

15.3

.0

.0

.3

.3

.0

.7

1.0

.0

.5

.5

.0

1.9

3.8

.0

.0

.0

.1

1.7

1.3

.3

20.2

State Total 3,290 645 3,940 722 75.8 798 414 87.1 52.4 
Table ^.-Public-supply water withdrawals and deliveries in Maryland, by coun

[State totals rounded to three significant figures. (Sources: Withdrawals, data compiled from Maryland Water Resources A

U.S. Geological Survey site-specific data bases; Population projections, data compiled from Maryland Department of Stat

I

ff§ 

f

5'

I

I 1

vo 

vo

Population served, in thousands

Water withdrawals, in million 

gallons per day

Water deliveries, by type of use, 

in million gallons per day

Source

County 

or city

Allegany

Anne Arundel

Baltimore

Calvert

Caroline

Carroll

Cecil

Charles

Dorchester

Frederick

Garrett

Harford

Howard

Kent

Montgomery

Prince Georges

Queen Annes

St. Marys

Somerset

Talbot

Washington

Wicomico

Worcester

Baltimore City

Surface 

water

58.68

82.02

638.62

.00

.00

25.49

15.98

.00

.00

57.14

4.87

32.24

165.84

.00

731.03

690.98

.00

.00

.00

.00

79.54

.00

.00

732.32

Ground 

water

2.03

237.42

1.00

14.94

9.82

10.19

10.90

65.82

15.43

27.82

1.98

86.35

.00

7.68

4.00

29.40

5.25

28.56

9.98

14.91

8.10

36.05

28.91

.00

Total

60.71

319.44

639.62

14.94

9.82

35.68

26.88

65.82

15.43

84.96

6.85

118.59

165.84

7.68

735.03

720.38

5.25

28.56

9.98

14.91

87.64

36.05

28.91

732.32

Source

Surface 

water

0.55

3.12

275.71

.00

.00

3.24

2.02

.00

.00

10.49

2.13

5.16

.00

.00

393.99

40.16

.00

.00

.00

.00

10.77

.00

.00

.00

Ground 

water

0.34

27.82

.03

1.43

1.21

1.74

1.31

6.54

2.83

2.12

.67

5.53

.00

1.19

.40

2.95

.66

2.80

1.60

2.28

1.27

6.40

7.75

.00

Total

0.89

30.94

275.74

1.43

1.21

4.98

3.33

6.54

2.83

12.61

2.80

10.69

.00

1.19

394.39

43.11

.66

2.80

1.60

2.28

12.04

6.40

7.75

.00

Domestic

6.21

32.75

65.50

1.29

1.09

5.63

2.77

5.89

1.92

1 .33

.90

9.09

17.10

1.07

78.85

70.67

.53

2.53

1.44

1.94

8.60

4.76

6.59

82.67

Commercial

0.85

6.14

14.04

.14

.07

.31

.20

.65

.42

1.29

.12

1.07

1.94

.06

22.64

8.21

.07

.27

.08

.23

1.15

.64

.78

25.44

Indust

1.

2.

14.

.

.

.

.

.

.

1.

.

.

.

.

2.

3.

.

.

.

.

1.

1

.

19.

State Total 3,310 657 3,970 747 78.9 826 420 86.8 49.
Table 5a.-Domestic water withdrawals (self-supplied) and deliveries from 

public suppliers in Maryland, by county, 1990

[State totals rounded to three significant figures. (Sources: Withdrawals, estimated using population 

projection data compiled from Maryland Department of State Planning, 1990, using per capita 

use of 80 gallons per day; Population projections, data compiled from Maryland Department of 

State Planning, 1990]

Self-supplied

Ground-water 

County withdrawals, in 

or Population, million gallons 

city in thousands per day

Allegany 

Anne Arundel

Baltimore

Calvert

Caroline

Carroll

Cecil

Charles

Dorchester

Frederick

Garrett

Harford

Howard

Kent

Montgomery 

Prince Georges 

Queen Annes 

St. Marys 

Somerset

Talbot

Washington 

Wicomico

Worcester

Baltimore City

14.24 

111.08

55.37

36.99

17.30

88.83

44.95

37.43

14.82

67.59

21.39

65.57

26.23

10.17

30.28 

14.59 

28.86 

47.86 

13.60

16.50

33.99 

38.66

6.66

.00

1.15 

9.61

4.46

3.05

1.44

7.16

3.61

3.01

1.20

5.47

1.71

5.32

2.14

.84

2.72 

1.19 

2.43 

3.91 

1.09

1.43

2.74 

3.50

.70

.00

Public-supplied

Population 

served, in 

thousands

60.71 

316.16

636.76

14.38

9.73

34.54

26.40

63.72

15.42

82.62

6.75

116.56

161.10

7.67

726.75 

714.68 

5.09 

28.11 

9.84

14.05

87.40 

35.68

28.37

736.01

Water 

deliveries, 

in millions 

gallons 

per day

7.05 

30.33

71.83

1.19

1.07

5.48

2.86

5.66

1.83

8.70

.84

8.71

14.86

1.01

74.13 

64.70 

.48 

2.21 

1.40

1.86

8.51 

4.85

6.53

87.89

Total

Withdrawals 

and deliveries, 

in millions 

gallons 

per day

8.20 

39.94

76.29

4.24

2.51

12.64

6.47

8.67

3.03

14.17

2.55

14.03

17.00

1.85

76.85 

65.89 

2.91 

6.12 

2.49

3.29

11.25 

8.35

7.23

87.89

State Total 843 69.9 3,940 414 484

26 Water Withdrawal and Use in Maryland, 1990-91
Table Sb.-Domestic water withdrawals (self-supplied) and deliveries from 

public suppliers in Maryland, by county, 1991

[State totals rounded to three significant figures. (Sources: Withdrawals, estimated using population 

projection data compiled from Maryland Department of State Planning, 1990, using per capita 

use of 80 gallons per day; Population projections, data compiled from Maryland Department of 

State Planning, 1990]

Self-supplied

County

or

city

AUegany

Anne Arundel

Baltimore

Calvert

Caroline

Carroll

Cecil

Charles

Dorchester

Frederick

Garrett

Harford

Howard

Kent

Montgomery

Prince Georges

Queen Annes

St Marys

Somerset

Talbot

Washington

Wicomico

Worcester

Baltimore City

State Total

Population,

in thousands

14.27

112.23

54.53

38.41

17.45

91.75

45.76

38.65

14.83

69.46

21.47

66.72

27.00

10.18

34.48

14.70

29.76

48.63

13.77

15.94

34.16

39.05

6.78

.00

860

Ground-water

withdrawals, in

million gallons

per day

1.15

9.72

4.39

3.17

1.45

7.39

3.67

3.11

1.22

5.62

1.72

5.42

2.20

.85

3.07

1.20

2.50

3.97

1.11

1.45

2.75

3.57

.71

.00

71.4

Public-supplied

Population

served, in

thousands

60.71

319.44

639.62

14.94

9.82

35.68

26.88

65.82

15.43

84.96

6.85

118.59

165.84

7.68

735.03

720.38

5.25

28.56

9.98

14.91

87.64

36.05

28.91

732.32

3,970

Water 

deliveries,

in millions

gallons

per day

6.21

32.75

65.50

1.29

1.09

5.63

2.77

5.89

1.92

10.33

.90

9.09

17.10

1.07

78.85

70.67

.53

2.53

1.44

1.94

8.60

4.76

6.59

82.67

420

Total

Withdrawals 

and deliveries,

in millions

gallons

per day

7.36

42.47

69.89

4.46

2.54

13.02

6.44

9.00

3.14

15.95

2.62

14.51

19.30

1.92

81.92

71.87

3.03

6.50

2.55

3.39

11.35

8.33

7.30

82.67

490

Water Withdrawal and Use in Maryland, 1990-91 27
Table 6a.~Commercial freshwater withdrawals (self-supplied) and deliveries from 

public suppliers in Maryland, by county, 1990

[State totals rounded to three significant figures. Source: Data compiled from Maryland Water Resources Administration files]

Self-supplied Public-supplied Total

Water withdrawals, in million 

gallons per day

County 

or 

city

Allegany 

Anne Arundel

Baltimore

Calvert

Caroline

Carroll

Cecil

Charles

Dorchester

Frederick

Garrett

Harford

Howard

Kent

Montgomery 

Prince Georges 

Queen Annes 

St. Marys 

Somerset

Talbot

Washington 

Wicomico

Worcester

Baltimore City 

State Total

Source

Surface 

water

0.03 

.38

.06

.01

.00

.46

.40

.00

.00

.97

.28

3.52

.04

.00

.02 

.15 

.01 

.00 

.00

.00

.08 

.00

.00

.00

6.41

Ground 

water

0.16 

6.52

.54

.37

.20

.46

.54

2.78

.20

.76

.61

.37

.20

.13

.41 

1.12 

.58 

1.46 

.36

.42

.21 

.56

.45

.00

19.4

Total

0.19 

6.90

.60

.38

.20

.92

.94

2.78

.20

1.73

.89

3.89

.24

.13

.43 

1.27 

.59 

1.46 

.36

.42

.29 

.56

.45

.00

25.8

Water 

deliveries, 

hi millions 

gallons 

per day

0.97 

5.69

15.39

.13

.06

.30

.21

.62

.45

1.09

.11

1.02

1.70

.05

21.45 

7.61 

.06 

.24 

.08

.22

1.13 

.69

.77

27.04

87.1

Withdrawals 

and deliveries, 

hi millions 

gallons 

per day

1.16 

12.59

15.99

.51

.26

1.22

1.15

3.40

.65

2.82

1.00

4.91

1.94

.18

21.88 

8.88 

.65 

1.70 

.44

.64

1.42 

1.25

1.22

27.04

113

28 Water Withdrawal and Use in Maryland, 1990-91
Table 6b.--Commercial freshwater withdrawals (self-supplied) and deliveries from 

public suppliers in Maryland, by county, 1991

[State totals rounded to three significant figures. Source: Data compiled from Maryland Water Resources Administration files]

Self-supplied Public-supplied Total

Water withdrawals, in million 

gallons per day

County 

or i 

city

Allegany 

Anne Arundel

Baltimore

Calvert

Caroline

Carroll

Cecil

Charles

Dorchester

Frederick

Garrett

Harford

Howard

Kent

Montgomery 

Prince Georges 

Queen Annes 

St. Marys 

Somerset

Talbot

Washington 

Wicomico

Worcester

Baltimore City 

State Total

Source

Surface 

water

0.03 

.07

.07

.01

.00

.43

.43

.00

.00

.04

.26

3.36

.05

.00

.01 

.15 

.01 

.01 

.00

.00

.10 

.00

.00

.00

5.03

Ground 

water

0.16 

7.38

.56

.39

.20

.48

.56

1.92

.24

.72

.63

.40

.24

.13

.43 

1.27 

.67 

1.49 

.46

.42

.24 

.59

.47

.00

20.0

Total

0.19 

7.45

.63

.40

.20

.91

.99

1.92

.24

.76

.89

3.76

.29

.13

.44 

1.42 

.68 

1.50 

.46

.42

.34 

.59

.47

.00

25.1

Water 

deliveries, 

in millions 

gallons 

per day

0.85 

6.14

14.04

.14

.07

.31

.20

.65

.42

1.29

.12

1.07

1.94

.06

22.64 

8.21 

.07 

.27 

.08

.23

1.15 

.64

.78

25.44

86.8

Withdrawals 

and deliveries, 

in millions 

gallons 

per day

1.04 

13.59

14.67

.54

.27

1.22

1.19

2.57

.66

2.05

1.01

4.83

2.23

.19

23.08 

9.63 

.75 

1.77 

.54

.65

1.49 

1.23

1.25

25.44

112

Water Withdrawal and Use in Maryland, 1990-91 29
Table 7a.--Industrial water withdrawals (self-supplied) and deliveries from public suppliers in M

I 

ff

I

f 

5- 

2

I

[State totals rounded to three significant figures. Source: Data compiled from Maryland Water Resources Administrat

Self-supplied withdrawals. In mlllllon gallons per day

Surface water

County

or city

Allegany

Anne Arundel

Baltimore

Calvert

Caroline

Carroll

Cecil

Charles

Dorchester

Frederick

Garrett

Harford

Howard

Kent

Montgomery

Prince Georges

Queen Anne

St. Marys

Somerset

Talbot

Washington

Wicomico

Worcester

Baltimore City

Fresh

45.06

.03

.00

.00

.00

.00

.02

.00

.06

.94

.00

.02

.21

.00

.00

.00

.00

.01

.00

.00

2.67

.00

.00

.00

Saline

0.00

.01

372.61

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.01

.00

.00

.00

.00

.00

6.86

Source

Ground water

Fresh

0.04

2.46

3.51

.02

.52

.08

.05

.01

.95

2.64

.03

.32

.05

.51

.06

.02

.28

.03

.06

.59

.21

2.29

1.83

4.53

Saline

0.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

Reclaimed

wastewater

0.00

.00

62.50

.00

.00

.04

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

Total, excluding 

reclaimed wastewater

Fresh

45.10

2.49

3.51

.02

.52

.08

.07

.01

1.01

3.58

.03

.34

.26

.51

.06

.02

.28

.04

.06

.59

2.88

2.29

1.83

4.53

Saline

0.00

.01

372.61

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.01

.00

.00

.00

.00

.00

6.86

Total

45.10

2.50

376.12

.02

.52

.08

.07

.01

1.01

3.58

.03

.34

.26

.51

.06

.02

.28

.05

.06

.59

2.88

2.29

1.83

11.39

Public

deliv

freshw

millio

pe

1

2

State Total 49.0 379 21.1 0.00 62.5 70.1 379 450 5
Table 7b. Industrial water withdrawals (self-supplied) and deliveries from public suppliers in M

[State totals rounded to three significant figures. Source: Data compiled from Maryland Water Resources Administrat

n.

f

5

I 

I

Self-supplied withdrawals. In miilllon gallons per day

Surface water

County

or city

Allegany

Anne Arundel

Baltimore

Calvert

Caroline

Carroll

Cecil

Charles

Dorchester

Frederick

Garrett

Harford

Howard

Kent

Montgomery

Prince Georges

Queen Anne

St. Marys

Somerset

Talbot

Washington

Wicomico

Worcester

Baltimore City

Fresh

44.99

.02

.00

.00

.00

.00

.01

.00

.06

.08

.00

.02

.24

.00

.00

.00

.00

.01

.00

.00

2.36

.00

.00

.00

Saline

0.00

.01

304.80

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.96

.00

.00

.00

.00

6.46

Source

Ground water

Fresh

0.04

2.19

2.63

.02

.42

.07

.05

.02

.83

2.54

.03

.36

.03

.26

.07

.02

.28

.03

.06

.55

.14

2.24

1.86

4.68

Saline

0.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

Reclaimed

wastewater

0.00

.00

62.50

.00

.00

.04

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

Total, excluding 

reclaimed wastewater

Fresh

45.03

2.21

2.63

.02

.42

.07

.06

.02

.89

2.62

.03

.38

.27

.26

.07

.02

.28

.04

.06

.55

2.50

2.24

1.86

4.68

Saline

0.00

.01

304.80

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.96

.00

.00

.00

.00

6.46

Total

45.03

2.22

307.43

.02

.42

.07

.06

.02

.89

2.62

.03

.38

.27

.26

.07

.02

.28

.04

1.02

.55

2.50

2.24

1.86

11.14

Public

deliv

freshw

millio

pe

1

State Total 47.8 312 19.4 0.00 62.5 67.2 312 379 4
Table 9&. Mining water withdrawals in Maryland, by county, 1990

if 

§

B

I5-

[State totals rounded to three significant figures. Source: Data compiled from Maryland Water Resources Administrat

Water withdrawals. In million gallons per day

Source

Surface water

County

or city

Allegany

Anne Arundel

Baltimore

Calvert

Caroline

Carroll

Cecil

Charles

Dorchester

Frederick

Garrett

Harford

Howard

Kent

Montgomery

Prince Georges

Queen Annes

St. Marys

Somerset

Talbot

Washington

Wicomico

Worcester

Baltimore City

Fresh

0.02

1.31

.12

.00

.01

.00

.42

.00

.85

.00

1.49

.06

.00

.00

.02

2.89

.00

29

.00

.00

.01

.01

.00

.00

Saline

0.00

.00

20.56

.00

.00

.00

.00

.13

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.01

.00

.00

.64

.01

Total

0.02

1.31

20.68

.00

.01

.00

.42

.13

.85

.00

1.49

.06

.00

.00

.02

2.89

.00

.29

.00

.01

.01

.01

.64

.01

Ground water

Fresh

0.01

.07

4.90

.00

.00

1.30

.32

.01

.00

5.21

5.26

.19

.00

.00

.27

.91

.01

.02

.01

.00

.62

.00

.01

1.39

Saline

0.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

Total

0.01

.07

4.90

.00

.00

1.30

.32

.01

.00

5.21

5.26

.19

.00

.00

.27

.91

.01

.02

.01

.00

.62

.00

.01

1.39

Total

Fresh

0.03

1.38

5.02

.00

.01

1.30

.74

.01

.85

5.21

6.75

.25

.00

.00

.29

3.80

.01

.31

.01

.00

.63

.01

.01

1.39

State Total 7.50 21.3 28.8 20.5 0.00 20.5 28.0 
Table Sb. Mining water withdrawals in Maryland, by county, 1991

[State totals rounded to three significant figures. Source: Data compiled from Maryland Water Resources Administrat

Water withdrawals. In million gallons per day

Surface water

Source

Ground water Total

I

r

County 

or city

Allegany

Anne Arundel

Baltimore

Calvert

Caroline

CarroU

Cecil

Charles

Dorchester

Frederick

Garret!

Harford

Howard

Kent

Montgomery

Prince Georges

Queen Annes

St. Marys

Somerset

Talbot

Washington

Wicomico

Worcester

Baltimore City

State Total

Fresh

0.02

.79

.13

.00

.01

.00

.55

.00

.87

.00

2.20

.03

.00

.00

.00

2.81

.00

.31

.00

.00

.01

.03

.00

.00

7.76

Saline

0.00

.00

3.00

.00

.00

.00

.00

.08

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.01

.00

.00

.67

.01

3.77

Total

0.02

.79

3.13

.00

.01

.00

.55

.08

.87

.00

2.20

.03

.00

.00

.00

2.81

.00

.31

.00

.01

.01

.03

.67

.01

11.5

Fresh

0.01

.04

3.42

.00

.01

1.06

.23

.01

.01

4.55

5.04

.17

.00

.00

.10

.45

.01

.01

.01

.02

.86

.00

.01

1.49

17.5

Saline

0.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

0.00

Total

0.01

.04

3.42

.00

.01

1.06

.23

.01

.01

4.55

5.04

.17

.00

.00

.10

.45

.01

.01

.01

.02

.86

.00

.01

1.49

17.5

Fresh

0.03

.83

3.55

.00

.02

1.06

.78

.01

.88

455

7.24

.20

.00

.00

.10

3.26

.01

.32

.01

.02

.87

.03

.01

1.49

25.3
I

ff

5-

w

9.

B>

Table ^.--Thermoelectric power water withdrawals in Maryland, by coun

[State totals rounded to three significant figures. Source: Data compiled from Maryland Water Resources Adm

Water withdrawals. In million gallons per day

Source

Surface Water

County

or city

Allegany

Anne Anmdel

Baltimore

Calvert

Caroline

Carroll

Cecil

Charles

Dorchester

Frederick

Garrett

Harford

Howard

Kent

Montgomery

Prince Georges

Queen Annes

SL Marys

Somerset

Talbot

Washington

Wicomico

Worcester

Baltimore City

State Total

Fresh

0.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

377.79

.00

.00

.00

.00

.00

41.48

.00

.00

.00

419

Saline

0.00

772.96

662.06

1,127.77

.00

.00

.00

1,196.14

1.46

.00

.00

.00

.00

.00

.00

615.15

.00

.00

.00

.00

.00

.00

.00

175.78

4^50

Total

0.00

772.96

662.06

1,127.77

.00

.00

.00

1,196.14

1.46

.00

.00

.00

.00

.00

377.79

615.15

.00

.00

.00

.00

41.48

.00

.00

175.78

4,970

Fresh

ground

water

0.00

.00

.00

.09

.00

.00

.00

.68

.04

.00

.00

.00

.00

.00

.00

1.04

.00

.00

.00

.00

.00

.00

.00

.00

1.85
I

ff

%5'

Table 9b. Thermoelectric power water withdrawals in Maryland, by coun

[State totals rounded to three significant figures. Source: Data compiled from Maryland Water Resources Adm

Water withdrawals, in million gallons per day

Source

Surface Water

County

or city

Allegany

Anne Arundel

Baltimore

Calvert

Caroline

CarroU

Cecil

Charles

Dorchester

Frederick

Garrett

Harford

Howard

Kent

Montgomery

Prince Georges

Queen Annes

St Marys

Somerset

Talbot

Washington

Wicomico

Worcester

Baltimore City

State Total

Fresh

0.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

.00

341.32

.00

.00

.00

.00

.00

72.55

.00

.00

.00

414

Saline

0.00

991.93

295.70

2,607.12

.00

.00

.00

1,166.55

1.11

.00

.00

.00

.00

.00

.00

582.04

.00

.00

.00

.00

.00

.00

.00

112.26

5,760

Total

0.00

991.93

295.70

2,607.12

.00

.00

.00

1,166.55

1.11

.00

.00

.00

.00

.00

341.32

582.04

.00

.00

.00

.00

72.55

.00

.00

112.26

6,170

Fresh

ground

water

0.00

.00

.00

.15

.00

.00

.00

.57

.01

.00

.00

.00

.00

.00

.01

.91

.00

.00

.00

.00

.00

.00

.00

.00

1.65
Table ^.^. Hydroelectric power water use in 

Maryland, by county, 1990

[State totals rounded to three significant figures. Sources: Withdrawals estimated 

based on annual power generation data obtained from Energy Information 

Administration, 1990, and Weisberg and Rose, 1985]

Freshwater use

County Thousand

or Million gallons acre-feet

city per day per year

Allegany 0.00 0.00

Anne Arundel 0.00 0.00

Baltimore 0.00 0.00

Calvert 0.00 0.00

Caroline 0.00 0.00

Carroll 0.00 0.00

Cecil 9.47 10.61

Charles 0.00 0.00

Dorchester 0.00 0.00

Frederick 0.00 0.00

Garrett 60.84 68.17 

Harford 25,616.44 28,704.50

Howard 0.00 0.00

Kent 0.00 0.00

Montgomery 0.00 0.00

Prince Georges 0.00 0.00

Queen Annes 0.00 0.00

St. Marys 0.00 0.00

Somerset 0.00 0.00

Talbot 0.00 0.00

Washington 225.19 25234

Wicomico 0.00 0.00

Worcester 0.00 0.00

Baltimore City 0.00 0.00

State Total 25,900 29,000

36 Water Withdrawal and Use in Maryland, 1990-91
Table Wb. Hydroelectric power water use in 

Maryland, by county, 1991

[State totals rounded to three significant figures. Sources: Withdrawals estimated 

based on annual power generation data obtained from Energy Information 

Administration, 1991, andWeisberg and Rose, 1985]

Freshwater use

County Thousand

or Million gallons acre-feet

city per day per year

Allegany 0.00 0.00

Anne Arundel .00 .00

Baltimore .00 .00

Calvert .00 .00

Caroline .00 .00

Carroll .00 .00

Cecil 8.97 10.06

Charles .00 .00

Dorchester .00 .00

Frederick .00 .00

Garrett 60.84 68.20 

Harford 20,473.97 22,951.32

Howard .00 .00

Kent .00 .00

Montgomery .00 .00

Prince Georges .00 .00

Queen Annes .00 .00

St. Marys .00 .00

Somerset .00 .00

Talbot .00 .00

Washington 1,327.00 1,487.67

Wicomico .00 .00

Worcester .00 .00

Baltimore City .00 .00

State Total 21,900 24,500

Water Withdrawal and Use in Maryland, 1990-91 37
Table 11. Livestock water withdrawals in Maryland, 

by county, 1990-91

[State totals rounded to three significant figures. Sources: Withdrawals estimated 

based on data from U.S. Department of Commerce, 1990 and U.S. Environmental 

Protection Agency, 1973]

Freshwater withdrawals, in million gallons per day

County

or

city

Allegany

Anne Arundel

Baltimore

Calvert

Caroline

Carroll

Cecil

Charles

Dorchester

Frederick

Garrett

Harford

Howard

Kent

Montgomery

Prince Georges

Queen Annes

SL Marys

Somerset

Talbot

Washington

Wicomico

Worcester

Baltimore City

State Total

Source

Surface water

0.05

.04

.13

.02

.04

.31

.10

.04

.01

.48

.22

.17

.10

.06

.11

.04

.06

.05

.02

.03

.31

.02

.03

.00

2.44

Ground water

0.02

.02

.16

.00

.28

.46

.20

.04

.19

1.40

.24

.21

.08

.21

.14

.02

.22

.08

.79

.18

.71

1.15

1.15

.00

7.95

Total

0.08

.07

.29

.02

.32

.77

.30

.08

.20

1.88

.46

.38

.18

.27

.25

.06

.28

.13

.81

.21

1.02

1.17

1.18

.00

10.4

38 Water Withdrawal and Use in Maryland, 1990-91
Table 12a.--Irrigation water withdrawals in Maryland, by county, 1990

[State totals rounded to three significant figures. Source: Withdrawals and acreage irrigated estimated based on data from L.E. C

Cooperative Extension Service, oral commun., 1991]

I

ff

I

f 

5"

I

Water withdrawals. In million gallons per d

Irrigated land by type of 

water, in thousand acres

County

or city

Allegany

Anne Arundel

Baltimore

Calvert

Caroline

Carroll

Cecil

Charles

Dorchester

Frederick

Garrett

Harford

Howard

Kent

Montgomery

Prince Georges

Queen Annes

St Marys

Somerset

Talbot

Washington

Wicomico

Worcester

Baltimore City

Fresh

0.09

.16

.96

.61

16.43

.52

.33

.76

17.60

.28

.27

.76

.16

2.34

.39

.34

9.17

.65

1.56

1.91

33

5.53

2.42

.00

Saline

0.00

.00

.02

.04

3.27

.00

.00

.02

.93

.00

.00

.00

.00

.26

.00

.00

.95

.20

.06

.00

.00

.62

.12

.00

Surface water

Fresh

0.08

.55

.37

.16

2.30

.14

.09

.23

1.30

.30

.11

.21

.07

.02

.45

.23

1.44

.19

.14

.33

.09

.56

.58

.01

Brackish

0.00

.00

.006

.01

.96

.00

.00

.01

.42

.00

.00

.00

.00

.08

.00

.00

.28

.06

.03

.00

.00

.28

.06

.00

Ground water

Fresh

0.00

.15

.20

.03

3.11

.06

.53

.06

6.56

.05

.00

.05

.02

1.80

.18

.53

1.89

.03

.57

.43

.04

2.22

.69

.00

Fresh

0.08

.70

.57

.19

5.41

.20

.62

.29

7.86

.35

.11

.26

.09

1.82

.63

.76

3.33

.22

.71

.76

.13

2.78

1.27

.01

State Total 63.6 6.49 9.95 2.20 19.2 29.1 
s

I

If

5- 

fr

V

B.

§D.

8 

S

8

Table 12b.~Irrigation water withdrawals in Maryland, by county, 1991

[State totals rounded to three significant figures. Source: Withdrawals and acreage irrigated estimated based on data from L.E. Carr, 

Cooperative Extension Service, oral commun., 1991]

Water withdrawals. In million gallons per d

Irrigated land by type of 

water, in thousand acres

County

or city

Allegany

Anne Arundel

Baltimore

Calvert

Caroline

Carroll

Cecil

Charles

Dorchester

Frederick

Garrett

Harford

Howard

Kent

Montgomery

Prince Georges

Queen Annes

St. Marys

Somerset

Talbot

Washington

Wicomico

Worcester

Baltimore City

Sate Total

Fresh

0.09

.16

.96

.61

16.76

.52

.33

.76

17.96

.28

.27

.76

.16

2.38

.39

.34

9.35

.65

1.59

1.95

.33

5.63

2.47

.00

64.7

Saline

0.00

.00

.02

.04

3.34

.00

.00

.02

.95

.00

.00

.00

.00

.26

.00

.00

.97

.20

.42

.00

.00

.63

.13

.00

6.98

Surface water

Fresh

0.10

.63

.42

.16

5.01

.17

.09

.23

1.99

.32

.12

.23

.12

.26

.55

.30

3.51

.44

.21

.76

.10

.85

.94

.01

17.5

Brackish

0.00

.00

.01

.01

2.24

.00

.00

.01

.64

.00

.00

.00

.00

.17

.00

.00

.65

.13

.42

.00

.00

.42

.08

.00

4.78

Ground water

Fresh

0.01

.18

.29

.03

6.81

.10

.57

.09

10.06

.10

.00

.08

.03

3.23

.43

.32

4.46

.03

.86

.76

.03

3.25

1.13

.00

32.8

Fresh

0.11

.81

.71

.19

11.82

.27

.66

.32

12.05

.42

.12

.31

.15

3.49

.98

.62

7.97

.47

1.07

1.52

.13

4.10

2.07

.01

50.4
Table 13a.--Aquaculture water withdrawals in Maryland, by county, 199

[State totals rounded to three significant figures. Source: Data compiled from Maryland Water Resources Adm

I

ff 

I

ff

D.

3

§D. 

f

S

Water withdrawals. In million gallons per day

Source

County

or city

Allegany

Anne Arundel

Baltimore

Calvert

Caroline

Carroll

Cecil

Charles

Dorchester

Frederick

Garrett

Harford

Howard

Kent

Montgomery

Prince Georges

Queen Annes

SL Marys

Somerset

Talbot

Washington

Wicomico

Worcester

Baltimore City

State Total

Surface Water

Fresh

0.01

.00

.00

.00

.00

.00

.00

.00

.00

251

1.52

.003

.00

.00

.00

.00

.00

.00

.00

.00

.80

.00

.00

.00

4.84

Saline

0.00

.00

159

.002

.00

.00

.00

.00

7.60

.00

.00

.00

.00

.00

.00

.00

.25

.13

.003

.00

.00

.001

.00

.00

958

Total

0.01

.00

1.59

.002

.00

.00

.00

.00

7.60

2.51

152

.003

.00

.00

.00

.00

.25

.13

.003

.00

.80

.001

.00

.00

14.4

Fresh 

ground

water

0.00

.01

.02

.08

.00

.00

.00

.00

.04

.004

.00

.00

.00

.00

.00

.00

.20

.002

.00

.00

4.15

.02

.002

.00

4.53
6

f 

ff

E?

S 

o.

c

r

c 

en

Table I3b.--Aquaculture water withdrawals in Maryland, by county, 199

[State totals rounded to three significant figures. Source: Data compiled from Maryland Water Resources Adm

§

o

Water withdrawals. In million gallons per day

Source

County

or city

Allegany

Anne Arundel

Baltimore

Calvert

Caroline

Carroll

Cecil

Charles

Dorchester

Frederick

Garrett

Harford

Howard

Kent

Montgomery

Prince Georges

Queen Annes

St Marys

Somerset

Talbot

Washington

Wicomico

Worcester

Baltimore City

State Total

Surface Water

Fresh

0.01

.00

.00

.00

.00

.00

.00

.00

.00

2.51

1.48

.003

.00

.00

.00

.00

.00

.00

.00

.00

2.41

.00

.15

.00

656

Saline

0.00

.00

3.27

.002

.00

.00

.00

.00

8.81

.00

.00

.00

.00

.00

.00

.00

.25

.17

.003

.00

.00

.001

.00

.00

12.5

Total

0.01

.00

3.27

.002

.00

.00

.00

.00

8.81

2.51

1.48

.003

.00

.00

.00

.00

.25

.17

.003

.00

2.41

.001

.15

.00

19.1

Fresh 

ground

water

0.00

.01

.07

.08

.02

.003

.00

.00

.03

.004

.00

.00

.00

.00

.00

.00

.20

.001

.00

.00

4.56

.02

.004

.00

5.00