U.S. Department of the Interior a U.S. Geological Survey

U.S. Geological Survey

Programs in Maryland and

the District of Columbia

The U.S. Geological Survey (USGS) 

has served as the Nation’s principal collector, repository, and interpreter of natural-science data for more than a century. 

In this capacity, the USGS in Maryland 

and the District of Columbia works in 

partnership with municipal public-works 

departments, public-health agencies, 

water and sanitation districts, other Federal agencies, and State and county agencies. This Fact Sheet describes some of 

the current USGS activities in Maryland 

and the District of Columbia.

Chesapeake Bay Resources 

and Restoration

Poor water quality has increased concern about the commercial, economic, and 

recreational values of Chesapeake Bay 

(fig. 1). Excess nutrients, sediment and 

toxic substances carried by streams flowing into the Bay from agricultural, urban, 

from the study is used by State and Federal 

water managers to assess the effectiveness 

of fertilizer-reduction measures and to 

develop methods for reducing nutrients in 

the Bay’s tributaries.

The USGS multidivisional Chesapeake 

Bay Ecosystem Program was initiated in 

1996 to collect and interpret data to help 

resource managers determine the effectiveness and response of the Bay ecosystem to 

nutrient additions and climatic variation 

during the last 15 to 400 years. This is being 

accomplished by determining the response 

of water quality and selected living 

resources of the Bay watershed and estuary 

as nutrient input is reduced; defining and 

evaluating the natural controls on the 

response in water quality and selected living 

resources to changes in nutrient loading; 

and providing data to resource managers to 

evaluate the effectiveness of components of 

the nutrient-reduction strategies.

National Water-Quality 

Assessment

The effect of human activity on water 

quality is a visible environmental issue in 

the Nation. The USGS is conducting the 

National Water-Quality Assessment 

(NAWQA) Program, a comprehensive 

assessment of water quality in 60 large 

Index of Subjects

Chesapeake Bay Resources and Restoration

National Water-Quality Assessment

U.S. Department of Defense Installation 

Restoration

Hydrologic Hazards

Acid Rain

Saltwater Intrusion

Water-Data Network and Water Use

Water Monitoring Partnership

Biological Resources

Geologic Mapping

Metallic Mineral Resource Assessment

Topographic Mapping

Earth Science Information Center

Cooperative Programs

Figure 1. National Water-Quality Assessment Program study areas.

and forested areas have adversely affected 

its water quality. The USGS has collected 

scientific data and provided technical support needed for managing and restoring the 

natural environment and resources of the 

Chesapeake Bay.

 In 1987, the States in the Chesapeake 

Bay watershed established an agreement to 

restore the Bay. The USGS supports the 

Chesapeake Bay Program through technical projects that provide information 

needed for managing the Bay’s resources. 

The USGS also participates in technical 

committees formed by the U.S. Environmental Protection Agency to guide restoration of the Bay. Through these activities, 

the USGS provides information about the 

quality of major tributaries that empty into 

the Bay and associated resources. One 

project measures the quantity of chemicals 

from fertilizers that enter the Bay in surface and ground waters. The information 

Earth Science in the Public Service
regions across the Nation. Major parts of 

two of these regions, the Potomac River 

Basin and the Delmarva Peninsula, are in 

Maryland (fig. 1). A small part of the 

Lower Susquehanna River Basin study 

unit, which drains into Chesapeake Bay, 

also lies within Maryland. The results from 

the NAWQA Program are producing useful water-quality information for managers 

at the national, State, and local levels. The 

Program is federally funded, but the USGS 

is working in partnership with a large 

group of other agencies that regulate water 

quality and manage resources.

The Delmarva Peninsula (fig. 1) 

NAWQA study, which was one of 7 pilot 

studies, was active during the period 1986–

1991 and it is scheduled to restart in 1997. 

The Delmarva study has given resource 

managers information about the extent of 

ground-water contamination caused by 

agricultural and residential land use. For 

example, the study has shown that high 

concentrations (greater than 10 milligrams 

per liter) of nitrate, which is a known hazard to human health, are commonly found 

in water samples from most parts of the 

surficial aquifer, including deep parts of 

the aquifer that are used for water supply. 

Pesticides generally are not found in deep 

parts of the surficial aquifer, but they could 

migrate to these zones during the next few 

decades. Data collected during the Delmarva study also showed that ground 

water with high concentrations of nitrate 

will continue to discharge to tributaries of 

Chesapeake Bay for at least the next few 

decades. Knowledge of ground- and surface-water quality is useful when policymakers and resource managers consider 

land-use changes and practices that are 

designed to improve water quality in the 

Chesapeake Bay watershed.

To meet the goals of the NAWQA Program in the Maryland–District of Columbia area of the Potomac River Basin 

(fig. 1), a wide variety of sampling 

approaches is being used to evaluate water 

quality in streams and ground water. 

Streams are being evaluated through either 

repetitive or “snapshot” sampling or both 

of water quality; of biological communities of insects, fish, and algae; of streambed sediment; and of clam and fish 

tissue. Ground-water quality is being evaluated by large-scale snapshot sampling of 

private wells in agricultural, urban, and 

suburban areas and repetitive sampling of 

monitoring wells at a small research site 

in the Potomac River Basin. The first 

phase of the water-quality assessment for 

the Potomac study unit focuses on nitrogen, phosphorus, and pesticides, which 

are three of the most common contaminants in water. Excessive amounts of these 

chemicals in streams and ground water in 

the Maryland–District of Columbia part of 

the Potomac River Basin have been identified as a major factor in the decline of 

water quality in Chesapeake Bay during 

the last several decades. One form of 

nitrogen, nitrate, is a known human-health 

hazard if it is in sufficiently high concentrations in drinking water. Pesticides, 

including herbicides and insecticides, 

have been linked to aquatic-health problems in Chesapeake Bay, and many pesticides are known or suspected to be toxic 

when they enter the food chain.

Sampling and analysis of water in the 

Potomac River Basin for nitrogen, phosphorus, and pesticides have begun to 

show which streams and ground-water 

reservoirs contain concentrations of these 

chemicals at levels harmful to humans 

and aquatic life; how concentrations of 

these chemicals vary seasonally; and the 

likely sources of these chemicals in 

streams and ground water. 

With this information, managers in 

Maryland and the District of Columbia and 

the general public will be able to make 

more informed decisions concerning 

water-supply protection and management 

and the restoration of Chesapeake Bay.

The Potomac and Delmarva NAWQA 

studies operate under the guidance of liaison committees with representatives from 

many Federal, regional, and State agencies 

and universities. 

U.S. Department of Defense 

Installation Restoration

Ground water supplies drinking water 

for many citizens of Maryland. Understanding how ground water becomes contaminated and how it can be cleaned up 

can improve protection of the State’s 

drinking-water supplies. Contamination of 

these supplies from leaking hazardouswaste sites can seriously affect human 

health; also, contamination leakage from 

these sites into Chesapeake Bay contributes to the overall decline of water quality 

of the Bay.

Since 1984, the USGS has assisted 

environmental managers at the Aberdeen 

Proving Ground (APG), Maryland (fig. 1), 

to identify areas of contaminated ground 

water. The USGS works with managers at 

the APG to locate areas of contamination, 

to develop ground-water-flow models that 

can be used to simulate the effects of various methods to reduce contamination at 

hazardous-waste sites, and to develop 

ways to mitigate contamination of wetland 

environments. These efforts have added to 

the ability of the environmental managers 

at the APG to develop effective and economical plans to reduce contamination and 

to address the concerns of local citizens.

Hydrologic Hazards

 Changes in climatic conditions can 

produce large variations in surface-water 

discharge; this was the case with the 100-

year flood of the upper Potomac River in 

September 1996 that followed the drierthan-normal year of 1995. Floods and 

droughts can adversely affect the agricultural sector of the State economy as well as 

public safety. The USGS actively works to 

improve estimates of the severity of floods 

and droughts. State, county, and local planning officials use these estimates to 

improve methods for water management 

and the design of infrastructure.

The Maryland State Highway Administration (MDSHA) provides cooperative 

funds for USGS studies of streambed 

scour at highway bridges and flood magnitude and frequency. The results of these 

studies are used by the MDSHA to reduce 

maintenance, repair, and replacement costs 

for highway bridges and to improve the 

safety of travelers during floods. The 

Maryland Geological Survey (MGS) and 

the Maryland Water Resources Administration (WRA), which cooperated with the 

USGS in a study of drought frequency, 

also use the results of USGS studies. The 

WRA uses the results of drought studies to 

improve analyses of water appropriation 

and use during drought, thereby allowing 

appropriate water-supply decisions to 

ensure that the water needs of Maryland’s 

citizens are met.

Acid Rain

 Acid rain, which results from burning 

oil and coal, affects the quality of streams, 

lakes, and ground water because of the 
inability of some areas of the Earth’s surface to neutralize the acidity in rainfall. 

Ground and surface waters affected by 

acid rain become more acidic than normal. 

Water can become so acidic that aquatic 

life dies, thus affecting the viability of fisheries and recreation. The USGS monitored 

the severity of acid rain in Frederick 

County, Maryland (fig. 1), from 1982 to 

1995, in cooperation with the Maryland 

Department of Natural Resources and the 

Maryland Department of the Environment.

Saltwater Intrusion

 Aquifers along Maryland’s coast can 

be contaminated by saltwater when too 

much water is pumped from them. The 

USGS, in cooperation with the MGS and 

other agencies, investigated the potential 

for saltwater intrusion in rapidly developing areas bordering the Atlantic Ocean 

and Chesapeake Bay, including Ocean 

City and Annapolis (fig. 1). The studies 

provide a scientific basis for ground-water 

development by mapping the present distribution of saltwater, developing predictive models to forecast future conditions, 

and establishing a monitoring well network to monitor water-level and waterquality trends.

Water-Data Network and 

Water Use

Most domestic and agricultural water is 

supplied by wells, whereas most public 

water supplies come from streams and rivers; all water supplied to the District of 

Columbia comes from the Potomac River. 

The USGS operates a network of 90 

streamflow-gaging stations and 330 waterlevel-gaging stations at wells to collect the 

data necessary to evaluate the amount and 

quality of the water resources in Maryland 

and the District of Columbia. The locations of continuous streamflow-gaging stations that have been operated since 1980 

are shown in figure 2.

The responsibilities of the USGS 

include monitoring ground-water levels, 

streamflow, and changes in water quality; 

supporting efforts to reduce contamination; detecting contamination and predicting contaminant movement in water; and 

supplying the data needed to maintain 

freshwater fisheries. The USGS systematic 

data-collection program receives cooperative support from the MDSHA, the MGS, 

the Washington Suburban Sanitary Commission, the U.S. Army Corps of Engineers, and other organizations. Current and 

easily available data on ground-water levels, streamflow, and water quality, make 

the USGS systematic data-collection program an integral part of water-resources 

management.

Water-Monitoring Partnership

The USGS is a partner with the Maryland Department of Natural Resources, the 

Maryland Department of the Environment, 

local governments, other Federal agencies, 

volunteer groups, academia, consultants, 

and industry in the newly formed Maryland Water Monitoring Council (MWMC). 

The MWMC fosters communication, collaboration, and cooperation among groups 

involved in water monitoring. Its goals are 

to promote the development of collaborative watershed-based monitoring strategies, to document monitoring activities in 

Maryland, and to promote the use of quality-assured procedures for sample collection, analytical methods, assessment, and 

data management. 

Biological Resources

The USGS, in cooperation with the 

Maryland Department of Natural 

Resources, is collecting information about 

the location and status of reptiles and 

amphibians. Study sites throughout Maryland are being used to test data-collection 

and monitoring methods for declining reptile and amphibian species.

The canvasback duck is an important 

part of the waterfowl hunting tradition of 

the Chesapeake Bay. The USGS is studying the causes for declining populations of 

wintering canvasbacks in the Bay during 

the past two decades.

The USGS participates as research and 

technical advisors in the Appalachian 

Clean Streams Initiative (ACSI), which is 

a comprehensive effort to implement 

acidic mine drainage prevention and 

watershed restoration. Through the ACSI, 

Maryland has begun restoration work on 

the North Branch Potomac River so that 

this water can again support productive 

fisheries and recreational areas.

Assateague Island National Seashore 

(fig. 1) is a research site for National Park 

Service and the USGS for testing vegetation mapping methods, which were developed in cooperation with private industry. 

Vegetation maps of National Parks in 

Maryland can be used for management 

and planning.

Geologic Mapping

County and quadrangle geologic maps 

contain information that can be used for a 

wide range of public and private applications such as land-use planning; groundwater availability and quality studies; finding and making the best use of earth 

resources such as natural aggregate for 

construction; hazard assessment; and engineering and environmental studies for 

waste disposal sites and construction 

projects. Map information is used in 

hydrologic and geologic studies by the 

USGS, the MGS, and the U.S. Department 

of Agriculture’s Natural Resources Conservation Service. Geologic maps, particularly those at 1:24,000 scale, are used by 

engineering companies for geotechnical 

studies for highways and other construction projects and by environmental firms 

for studies of pollution and remediation of 

individual sites throughout the State. Other 

companies use geologic maps and cross 

sections for siting industrial water wells. 

Figure 2. Locations of continuous streamflowgaging stations in Maryland and the District of 

Columbia that were active since 1980
For More

Information

The USGS, in cooperation with the 

MGS, produces technical papers and maps 

about the geology of Maryland as the data 

become available.

Since 1968, the USGS, in cooperation 

with MGS, has mapped bedrock and surficial geology throughout Maryland at 

scales of 1:62,500 and 1:24,000. This 

includes 1:24,000 scale mapping of the 

Maryland Piedmont region since 1991.

Currently, the USGS, in cooperation 

with MGS, is producing a geologic map of 

the Chesapeake and Ohio Canal National 

Historical Park for the National Park Service (C & O Canal, fig. 1). The Geology 

of the Mid-Atlantic Corridor Project, 

which is being conducted in cooperation 

with the MGS, maps geology in the urban, 

suburban, and outlying rural areas of the 

Baltimore, Maryland–Washington D.C. 

region. The results of the project will be 

in the form of 1:100,000 scale geologic 

maps in standard paper and digital formats 

to help meet information needs for environmental, resource, land-use, hazard, 

and engineering applications in the midAtlantic urban corridor. 

Metallic Mineral Resource 

Assessment

Economic growth and development in 

Maryland depend in part on the availability of local mineral sources for use in 

industry, manufacturing, and the maintenance and upgrading of the region’s infrastructure. The USGS, in cooperation with 

State Geological Surveys and resource 

agencies, including the MGS, is inventorying known mineral resources and assessing the potential for as-yet-undiscovered 

mineral resources, based on geological, 

geophysical, and geochemical studies. 

Information in digital and paper form will 

assist Federal and State land-management 

agencies, regional planners, industry, and 

local governments to ensure adequate supplies of minerals at the lowest possible 

cost and promoting sound management of 

the region’s very substantial mineral 

resources.

Topographic Mapping

The demand for maps and digital 

cartographic data is widespread and it 

continues to grow. The USGS strives to 

ensure availability of map data in graphic 

and digital form through timely data collection and revision procedures. The 

USGS fosters partnerships with State and 

Federal agencies to improve data-collection activities and to maximize resource 

sharing. The USGS, in cooperation with 

the Federal Geographic Data Committee’s 

Wetlands Subcommittee, assisted the 

WRA and several Federal agencies to 

assess the causes of reporting discrepancies for wetlands in Wicomico County, 

Maryland by producing 1,200 digital 

plots that compared wetland interpretations from the Departments of the Interior, Agriculture, and Commerce, and 

from the Maryland WRA.

Among the most popular and versatile 

products of the USGS are its 1:24,000-

scale topographic maps (1 inch on the map 

represents 2,000 feet on the ground). These 

maps depict basic natural and cultural features of the landscape, such as lakes and 

streams, highways and railroads, boundaries, and geographic names. Maryland 

and the District of Columbia are covered 

by 264 maps at this scale.

Earth Science Information 

Center

The Earth Science Information Center 

(ESIC) in Baltimore, Maryland, was established under a cooperative agreement 

between the USGS and the Maryland Geological Survey. The ESIC provides information on topics such as cartography, 

geography, digital data, remote sensing, 

geology, geophysics, geochemistry, 

hydrology, geohydrology, aerial photography, and land use. It is supported by the 

USGS with reference materials, technical 

assistance, training, outreach activities, 

and access to USGS data bases.

Cooperative Programs

The USGS cooperates with about 30 

local, State, and Federal agencies in Maryland and the District of Columbia. Cooperative activities include water-resourcesdata collection, studies of water availability and quality, mineral-resource assessments, and mapping. For information on 

geologic and topographic reports published by the State of Maryland (including 

maps, images and computerized data), 

contact the Maryland Geological Survey, 

2300 St. Paul Street, Baltimore, Maryland 

21218, (410) 554-5500.

USGS state representative

8987 Yellow Brick Road

Baltimore, MD 21237

(410) 238-4200

Fax: (410) 238-4210

Email: dc_md@usgs.gov

Additional earth science

information can be found by

accessing the USGS Home Page

on the World Wide Web at

http://www.usgs.gov/

For more information on

all USGS reports and products

(including maps, images,

and computerized data), call

1-800-USA-MAPS

The USGS provides maps,

reports, and information to help

others meet their needs to manage,

 develop, and protect America’s water,

energy, mineral, biological, and land

resources. We help find the natural

resources needed to build tomorrow,

and supply the scientific understanding needed to help minimize or mitigate the effects of natural hazards

and environmental damage caused

by natural and human activities. The

results of our efforts touch the daily

 life of almost every American.

U.S. Geological Survey

Fact Sheet FS-020-96