Index of Subjects

Water Supply

Maintaining Adequate Streamflow

Aquifer Studies

Floods and Droughts

Water Quality

Point- and Nonpoint-Source Contamination

Saltwater Intrusion in Aquifers

Marine Environment of the New York–New 

Jersey Metropolitan Region

Water-Data Collection

Mineral-Resource Assessments

Biological Resource Studies

Magnetic Field Data Base

Topographic and Geologic Mapping

Earth Science Information Centers

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

re

n

U.S. Geological Survey

Programs in New Jersey

The U.S. Geological Survey (USGS) has 

been assessing and monitoring the natural 

resources and natural hazards of New Jersey 

for more than a century. Through cooperative 

programs with more than 25 Federal, State, 

and local agencies, the USGS studies water 

supply, water quality, floods and droughts, 

and many other natural-resource issues 

throughout the State. USGS information is 

the starting point for many scientific investigations, construction projects, and recreational activities. In 1996, USGS personnel 

in New Jersey responded to more than 1,000 

information requests from businesses, government agencies, and the public.

Water Supply

New Jersey’s water resources are constantly strained by the competing needs of 

the growing population, agriculture, industry, 

and recreation. During 1989–90, statewide 

use of surface and ground waters averaged 

1,680 and 561 million gallons per day, 

respectively.

The USGS, in cooperation with the New 

Jersey Department of Environmental Protection (NJDEP), is addressing current watersupply problems and future water needs 

with a three-phase program. First, fieldwork data are collected to document current 

conditions and to assess the scope of any 

potential problem. Next, maps, tables, and 

graphs are prepared to identify available 

resources and possible problems. And third, 

computer models are developed to simulate 

surface- and ground-water flow and to predict the feasibility and effects of water-use 

alternatives for the future. This information 

is available to water managers and others 

who must ensure an adequate supply of 

water into the next century.

Maintaining Adequate Streamflow

The USGS is addressing increasing concern about reduced streamflow as a result of 

urbanization, regional wastewater-treatment 

facility operation, stream-channel alterations, ground-water pumpage, and interbasin surface-water transfers. Because 

decreasing streamflow can adversely affect 

water availability and quality and stream 

ecology, the NJDEP has set minimum passing-flow requirements for critical streams. 

Through its streamflow-gaging station network, the USGS provides the NJDEP with 

the information needed to determine if these 

minimums are being maintained.

Aquifer Studies

Many USGS water-supply studies have 

focused on fast-growing areas of northern 

New Jersey. Intensive water-resource assessments were conducted in the Ramapo River 

Basin in Bergen County and the Rockaway 

River, Lamington River, and Green Pond 

Brook Basins in Morris and Hunterdon 

Counties (fig. 1), where valley-fill aquifers 

and surface water are used extensively for 

water supply. The ground-water-flow model 

developed for the ground-water-resource 

assessment in the Lamington River Basin 

was later used to delineate the areas that 

contribute recharge to water-supply wells. 

This information may be used by local governments to explore the development of new 

zoning regulations to protect ground-water 

supplies from surface contamination.

The USGS also studied the water 

resources in parts of Mercer, Hunterdon, 

and Somerset Counties, where fracturedrock aquifers are the primary source of supply (fig. 1). This study provided new information about the geologic features that 

control ground-water flow in this area. This 

information may be used by water-resources 

managers in this and similar areas throughout the Eastern United States.

Ground-water withdrawals from aquifers 

in the Coastal Plain of southern New Jersey 

have increased steadily since 1900, lowering 

water levels by more than 200 feet in some 

areas. Every 5 years, the USGS, in cooperation with the NJDEP, measures water levels 

in more than 1,000 Coastal Plain wells during a 2-month period to prepare a “snapshot” 

of ground-water conditions. In 1985–86, the 

NJDEP used these measurements to identify 

two “Critical Water-Supply Management 

Areas”—areas where the ability of an aquifer 

to meet future water demand is compromised—and mandated studies to find new 

sources of water in these areas (fig. 2).

In 1983, water levels in all four aquifers 

underlying Critical Water-Supply ManageFigure 1. Location of aquifer study areas. ment Area 1 were below sea level as a result 

EXPLANATION

Valley-fill aquifer

study area

Fractured-rock

aquifer study

area

Surficial-aquifer

study area

0 20 MILES

0 20 KILOMETERS

75 74

41

40

39

SUSSEX

WARREN

BERGEN

PASSAIC

MORRIS

HUNTERDON

ESSEX

UNION

SOMERSET

MIDDLESEX

MERCER MONMOUTH

BURLINGTON

OCEAN

CAMDEN

ATLANTIC

SALEM

GLOUCESTER

CUMBERLAND

CAPE

MAY

Cape May

Wildwood

HUDSON

Earth Science in the Public Service
●

●

Passaic River

Basin

Somerset

County

Elm Tree

observation

well 3

Allaire State

Park

observation

well C

C O A S T A L

P L A I N

FALL

LINE

EXPLANATION

●

Critical Water-Supply

Management Area

Flood-WarningNetwork Area

Observation well

1

2

0 20 MILES

0 20 KILOMETERS

75 74

41

40

39

1960

1965

1970

1975

1980

1985

1990

1995

WATER YEAR

WATER LEVEL, IN FEET

BELOW SEA LEVEL40

80

120

160

Elm Tree obervation well 3

Allaire State Park

obervation well C

of ground-water withdrawals, thus causing 

salty water to flow toward the aquifers. 

Results of a USGS study showed that even if 

pumpage were reduced by 50 percent after 

1990, water levels would still be below sea 

level in 2010. The Manasquan Reservoir was 

built in 1989 as a supplemental source of 

water. Previously, the water level in a representative well (Allaire State Park observation 

well C) had declined 107 feet (fig. 3). After 

the reservoir began supplying water and 

ground-water pumpage decreased, the water 

level in the observation well rose 93 feet.

In Critical Water-Supply Management 

Area 2, pumping from the Potomac–Raritan–

Magothy aquifer system has caused the 

water level in a representative well (Elm Tree 

observation well 3) to decline 50 feet since 

1968 (fig. 3). The USGS and the NJDEP are 

evaluating the availability of water from 

other aquifers in this area.

Surficial aquifers are being considered as 

potential alternative sources of water supply 

throughout southern New Jersey. The USGS, 

in cooperation with the NJDEP, is evaluating 

the water-supply potential of surficial aquifers in drainage basins defined as “regional 

planning areas.” Studies have been completed in four areas, and three additional 

areas are being studied (fig. 1).

Floods and Droughts

The USGS participates in several programs that provide information that helps 

protect the lives and property of New Jersey 

residents from flooding. The Passaic River 

Basin is one of the most flood-prone river 

basins in the country. The April 1984 flood 

in the Passaic Basin claimed three lives, 

caused $335 million in damages, and forced 

about 9,400 people from their homes. The 

USGS operates 18 streamflow-gaging stations throughout the Passaic River Basin 

(fig. 2) that provide data to emergency-management officials. This information is provided on a real-time basis by satellite, radio, 

and telephone communication and is an 

integral part of the Passaic Flood-Warning 

System. These streamflow data and data 

from 14 other gages throughout the State 

also are available hourly on the USGS New 

Jersey District “home page” at:

http://wwwnj.er.usgs.gov/rt-cgi/gen_tbl_pg

The USGS, in cooperation with Somerset 

County (fig. 2), has installed rainfall and 

streamflow gages that transmit data to the 

County and the National Weather Service 

over a radio network. The USGS is (1997) 

overseeing the installation of the New Jersey 

Tide Telemetry System to monitor tide levels 

at 25 sites on back bays to provide information needed for effective evacuation of shore 

communities during powerful coastal storms. 

Data collected by the various flood-warning 

telemetry systems is shared over a radio system with more than a dozen Federal, State, 

and county agencies.

The USGS has collected flood data 

throughout the State since 1902. These data 

are furnished to floodplain-management and 

transportation officials, consulting engineers, 

and the general public. This information is 

needed for making zoning and land-use decisions that seek to minimize flood damage 

and to optimize the design of roads, highway 

culverts, and bridges.

Knowledge of drought magnitude and 

frequency is important for water managers, 

regulators, engineers, and planners. Since 

1959, the USGS has collected streamflow 

data under base-flow conditions at many 

sites in addition to the long-term streamflow-gaging stations. These measurements, 

made at more than 350 sites throughout the 

State, are used to improve the accuracy of 

estimates of the low-flow characteristics of 

streams at or near those sites. These estimates are used to set effluent limits for 

point-source discharges, such as sewagetreatment plants, and to set minimum passing-flow requirements for surface-watersupply diversions to protect streamwater 

quality and stream ecology.

The flood-warning telemetry systems discussed above are also used to manage surface-water supplies during normal and 

drought conditions to help maintain mandated streamflows and to assess the severity 

of drought conditions. A computer simulation model of the Raritan River Basin watersupply system was recently developed in 

cooperation with the New Jersey Water Supply Authority. This computer model provides 

a technical basis for evaluating the effects of 

alternative patterns of operation of the watersupply system in relation to future drought 

risks. Water-supply managers can use the 

model during droughts to forecast the likelihood that the reservoirs and streamflows will 

fall below specified levels.

Water Quality

Water quality has long been an important 

issue to New Jersey residents. As part of the 

USGS National Water-Quality Assessment 

Program (NAWQA), USGS hydrologists in 

New Jersey are assessing surface- and 

ground-water quality in the State’s coastal 

drainage basins. In New Jersey, the Program 

is focusing on the effect of land use on shallow ground-water quality, spatial and temporal trends in ground-water quality, well 

vulnerability to contamination from various 

sources, toxic materials in surface water, 

stormwater quality, and the effects of interbasin surface-water transfers on water quality. The study includes a comprehensive 

assessment of the effects of urban growth on 

water quality. This study of toxic constituents from atmospheric and land sources and 

their effects on surface water, ground water, 

and aquatic biota in an urban area is a pilot 

project for the NAWQA program.

In almost every part of the State, some 

type of contaminant poses a serious hazard to 

the quality of the water supply. The USGS is 

addressing many of these hazards through 

various programs and studies. The quality of 

ground and surface water can be affected by 

contaminants from point sources, such as 

those from wastewater-treatment facilities, 

landfills, leaking underground storage tanks, 

and spill sites; contaminants from nonpoint 

sources, such as pesticides and fertilizers, 

whose use is widespread over a large area; 

and contaminants such as radon, corrosive 

Figure 2. Location of Critical Water-Supply 

Management Areas, flood-warning network areas, 

and two observation wells.

Figure 3. Water levels in Elm Tree observation 

well 3 and Allaire State Park observation well C.
water, and saltwater, which are found naturally over large areas. The USGS, in cooperation with the NJDEP, is developing a new 

method to determine which of the State’s 

watersheds are most affected by point and 

nonpoint sources of contamination. By using 

the new method, State, county, and local 

water-resource managers will be able to 

identify and prioritize areas in which detailed 

water-quality investigations are needed and 

to focus on contaminants of concern.

The addition of composted sewage 

sludge to the soil can facilitate mandated 

revegetation of sand and gravel pits. The 

USGS is monitoring the mobilization of 

nutrients and metallic contaminants leached 

from the sludge at a test site in Ocean 

County; study results may be used for planning and managing sludge use or disposal 

or both. In addition, the spatial and vertical 

distributions of radon, lead, mercury, and 

nitrate in aquifers in targeted drainage 

basins with different land uses are being 

evaluated to determine how the concentrations of these contaminants are related to 

land use and hydrogeology.

Point- and Nonpoint-Source 

Contamination

Ground- and surface-water contamination 

with toxic chemicals is a major problem in 

New Jersey, as evidenced by the more than 

600 contaminated sites identified by the 

NJDEP. As part of its national research program, the USGS is developing innovative 

methods to remediate water contaminated 

with toxic chemicals.

USGS investigators, in cooperation with 

those of the New Jersey Geological Survey 

(NJGS), were able to differentiate among 

the possible sources of arsenic contamination in soils at and near a former industrial 

site in Monmouth County. In addition to 

contamination from the industrial site, both 

natural background concentrations and 

residual amounts of arsenic from pesticide 

use in orchards before the 1950’s were 

found to be significant.

The USGS maintains two research sites 

in New Jersey—a gasoline-spill site in 

Atlantic County and a chlorinated-solvent 

leak site in Morris County. The research 

objectives at these sites are to characterize 

the natural hydrologic, chemical, and microbial processes that control the dispersal and 

persistence of these chemicals in the subsurface; to evaluate the potential for natural processes to clean up the contamination; and to 

develop economical methods that can be 

used to clean up contamination at similar 

sites.

Pesticides from agricultural land, which 

covers about 20 percent of the State, have 

been detected in ground and surface waters 

in New Jersey. The USGS, in cooperation 

with the NJDEP, identified areas where the 

water is most vulnerable to pesticide contamination. The NJDEP subsequently used 

this information to develop a program to 

monitor pesticides in drinking water, saving 

an estimated $5.1 million annually as a 

result of reduced analysis requirements for 

low-vulnerability water supplies.

Increased concentrations of naturally 

occurring radon, uranium, and radium have 

been detected in ground water in parts of 

New Jersey. The USGS, in cooperation with 

the NJDEP, has conducted studies to 

describe the geologic settings in which these 

substances that pose a hazard to public health 

are most likely to be found and how they 

move through the ground-water system. This 

information can be used to avoid siting wells 

in those areas where ground water is most 

likely to contain radioactive contaminants.

Saltwater Intrusion in Aquifers

Ground-water withdrawals in coastal 

areas have resulted in the landward movement of salty ground water into aquifers that 

are used heavily for water supply. As a result, 

more than 120 wells in Cape May County 

alone have been abandoned since 1940. The 

USGS, in cooperation with Lower Township 

and the Cities of Cape May and Wildwood, 

developed a ground-water-flow model that 

can be used to estimate saltwater movement 

in coastal areas under various hypothetical 

ground-water-withdrawal schemes. The estimates help water managers decide how best 

to distribute future withdrawals to minimize 

additional saltwater intrusion.

Marine Environment of the New 

York–New Jersey Metropolitan 

Region

The New York–New Jersey metropolitan 

area is the most populated coastal region in 

the United States. The harbor estuary and 

offshore area are used for waste disposal, 

transportation, recreation, and commercial 

fishing. As a result of these activities over the 

last century, bottom sediments in some areas 

are contaminated. To address the continuing 

need to identify areas in which disposal of 

material dredged from the harbor is environmentally acceptable, the USGS is conducting 

a long-term multidisciplinary study to map 

the distribution of contaminated sediments 

and to develop the ability to predict the transport and long-term fate of the sediments and 

contaminants. Information from this study of 

seafloor geologic processes may be used by 

Federal, State, and local agencies for managing the use of the coastal ocean, and by scientists for planning and conducting research 

and monitoring activities. The ongoing 

research and mapping study is conducted 

cooperatively with scientists at the Woods 

Hole Oceanographic Institution, Rutgers 

Institute of Marine and Coastal Sciences, the 

NJGS, the National Marine Fisheries Service, and the U.S. Army Corps of Engineers.

Water-Data Collection 

The USGS collects, stores, and disseminates streamflow, ground-water-level, and 

water-quality data from statewide networks. 

Streamflow data are used by water- and 

emergency-management authorities and regulatory agencies to forecast floods, to manage reservoirs, and to ensure compliance 

with legal minimum streamflow requirements. Water-quality data are used by the 

NJDEP to enforce the New Jersey Water 

Quality Planning Act and the Clean Water 

Act, which are aimed at ensuring the continued availability of safe drinking-water supplies and lakes and streams that are safe for 

swimming and fishing. The networks consist 

of 216 streamflow-measurement sites, 172 

ground-water-level-measurement sites, 100 

surface-water-quality sites, and 39 groundwater-quality sites. All data are available to 

the public in hardcopy or digital form.

Mineral-Resource Assessments

The USGS is completing a prototype 

quantitative national assessment of the 

resources of five commonly used metals—

gold, silver, copper, lead, and zinc—that 

lists significant known deposits, delineates 

areas with mineral potential, estimates the 

quantity of each metal likely to be present, 

and identifies tracts that may contain deposits of those metals. The results of this assessment will enable the USGS to respond more 

quickly to requests from Congress, Federal 

and State agencies, industry, and the public 

for information about these mineral 

resources throughout the country and to 

provide mineral information to land-use 

planners who are concerned with resourcemanagement issues.

Like many eastern states, New Jersey 

depends on diminishing resources of locally 

derived materials that are required for maintaining and constructing its buildings and 

infrastructure. Therefore, as a complement to 

the national assessment, the USGS is also 

conducting a comprehensive regional assessment of other metallic and industrial mineral 

resources in the Eastern United States.
For More

Information

The USGS now has two minerals data 

bases: the previously available Mineral 

Resources Data System and the Mineral 

Availability System, an information resource 

that was transferred to the USGS from the 

Bureau of Mines. These data bases are the 

principal tools used by the USGS for mineral-resource assessments and research. 

Between them, they contain information on 

hundreds of thousands of mineral-deposit 

and processing locations around the world, 

including the sites of more than 1,000 deposits of both metals and nonmetals in New Jersey. Information on these deposits has been 

compiled in cooperation with the NJGS. 

Both data bases are available on CD-ROM.

Biological Resource Studies

The Biological Resources Division, formerly the National Biological Service, conducts research and provides scientific data 

needed for effective management of, and 

preservation of economic benefits related 

to, living resources in and along New Jersey’s rivers and coastlines. As part of the 

Delaware Bay Estuary project, the USGS is 

working with several State and local agencies to develop a Gap Analysis Program to 

help identify plant and animal distribution 

patterns and their relation to land ownership and development. USGS scientists are 

also evaluating the extent of dioxin contamination in fish in the lower Passaic River 

and Newark Bay to provide information for 

natural-resource managers.

Magnetic Field Data Base

Because dense vegetation and soils 

cover most of the rocks in New Jersey, 

geologists must rely on methods other than 

direct observation to assess some aspects of 

the State’s rocks and geologic structures. 

These methods include geophysical studies 

such as aeromagnetic surveys, in which the 

magnetic field is measured from aircraft 

flying low-level, closely spaced flight lines. 

The resulting data are used to help interpret 

the geologic framework of a region. The 

USGS, in cooperation with the NJGS, 

recently created a new, digital magnetic 

field data base and produced a magneticanomaly map of the State, which were compiled from available published and unpublished analog and digital magnetic data. 

Although these data were obtained from 

aeromagnetic surveys conducted at different times, spacings, and elevations, analytical techniques were used to create 

a consistent data set. This procedure results 

in a comprehensive view of the magnetic 

characteristics of the rock units in New 

Jersey, and consequently, increases understanding of the State’s geology. The 

magnetic data have been released in 

cooperation with the NJGS.

Topographic and Geologic 

Mapping

The USGS in cooperation with other 

Federal and State agencies is preparing color 

infrared (CIR) digital orthophotoquad maps 

(DOQ’s) for the all of New Jersey. A DOQ is 

derived from digitized aerial photographs, 

with displacement caused by camera tilt and 

terrain relief removed; it combines the image 

characteristics of a photograph with the geometric qualities of a map. DOQ’s are becoming increasingly popular as components in 

geographic information systems. The 

NJDEP has cooperated in producing the 

statewide CIR aerial photographs from 

which the DOQ’s are being prepared.

The USGS and the NJGS, as part of the 

National Cooperative Geologic Mapping 

Program, have recently completed a new 

suite of 1:24,000-scale geologic quadrangle 

maps, as well as six new 1:100,000-scale 

bedrock- and surficial-geology maps. The 

smaller scale series is part of the State’s 

efforts toward producing a new geologic 

map of New Jersey. The new information 

shown on these maps is useful for solving 

environmental problems; assessing groundwater contamination, engineering hazards, 

and aquifer recharge; addressing land-use 

issues; selecting well locations; and 

planning well construction.

Earth Science Information Centers

Earth Science Information Centers 

(ESIC’s) provide information to the public 

about USGS programs, products, and technological developments. The ESIC in 

Trenton was established under a cooperative agreement between the USGS and the 

NJGS. As part of the national ESIC network, this office provides information on 

such earth-science topics 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 and outreach activities, and access 

to USGS data bases.

USGS state representative

810 Bear Tavern Road, Suite 206

West Trenton, NJ 08628

(609) 771-3900

Fax: (609) 771-3915

Email: dc_nj@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-030-96