U.S. Department of the Interior

U.S. Geological Survey

USGS Fact Sheet 030-99

December 1999

New Hampshire

Geologic Mapping

On September 30, 1998, representatives of the U.S. Geological Survey

(USGS) joined the Commissioner of

the New Hampshire Department of

Environmental Services (NHDES),

and the New Hampshire State Geologist as they presented Governor

Jeanne Shaheen with the recently

published Bedrock Geologic Map of

New Hampshire (fig. 1). This map

was published by the USGS, in

cooperation with the State of New

Hampshire and the Department of

Energy. USGS scientists participated

in the geologic fieldwork and preparation of the map.

As part of a bedrock aquifer assessment project, USGS geologists

completed bedrock geologic maps of

two 1:24,000-scale quadrangles in

southern New Hampshire to determine if there is a correlation between

rock type and the ground-water yields

from wells drilled in these areas. The

value of bedrock geologic maps for

exploration of ground water in

fractured bedrock in New England is

being investigated.

The USGS also is making a detailed

bedrock geologic map of the Hubbard

Brook watershed, a long-term research area of the U.S. Forest Service

(USFS) in central New Hampshire

and at the nearby Mirror Lake

fractured bedrock research site

(fig. 2). The geologic map data will

be compared to subsurface bedrock

structures observed in the two well

fields at Mirror Lake to determine

how well the subsurface structures

characterize larger areas.

Detailed mapping of surficial geology

by the USGS, in cooperation with the

New Hampshire Department of

Resources and Economic Development and NHDES, has continued for

the last 10 years. About 30 percent of

the State has been mapped and a

variety of map products that show the

distribution of sand, gravel, silt, clay,

and till (unsorted sand, gravel, silt,

and clay) are available. This mapping

is supported by an external source of

funding for the National Cooperative

Geologic Mapping Program. The

USGS program comprises a wide

variety of economic and environmental issues by supporting geologic

mapping projects in New Hampshire.

These issues include forecasting

resource management in the sand and

gravel industry, ground-water management, transportation engineering,

and environmental remediation.

Ground-Water Resources

Many towns and communities in New

Hampshire have limited or no sand

and gravel aquifers that can support

high-yielding water wells. These

towns must rely on surface-water

sources or locate and drill highyielding zones within fractured

bedrock. Typically, bedrock wells

provide low yields, but the USGS, in

cooperation with the NHDES, is

investigating methods of locating

high-yielding zones in bedrock.

In New England, bedrock initially

was fractured more than 90 million

years ago when stresses in the earth

folded and cracked the rock. The

weathering has since produced

surface patterns, that could indicate

the location of underlying large

fractures. Some of these fractures

could act as pathways for groundwater flow that, when intercepted by

drilled wells, have the potential of

yielding large quantities of ground

water for public supply. A series of

Figure 2. Index map of the Bedrock

Regional Aquifer Study area in

southern New Hampshire and at

Mirror Lake, Grafton county, in westcentral New Hampshire.

0 10 Km

Windham

Pinardville

Mirror Lake Study

and Hubbard Brook

Experimental Forest

71o

45o

44o

43o

72o

Mt. Kineo

Woodstock

Southern New Hampshire

Study

Figure 1. The bedrock geologic map of

New Hampshire is presented to

Governor Jeanne Shaheen by

representatives from the USGS and

the NHDES.
science for a changing world

maps showing the location of these

surface patterns statewide was

produced by the New Hampshire

Bedrock Aquifer Assessment project.

As part of this project, the USGS, in

cooperation with the NHDES, is

comparing the quality of well water

with the type of rock in which wells

were drilled. More than 20,000 wells

drilled in New Hampshire since 1982

were geographically located and a

total of 1,353 bedrock wells were

matched with 1,818 water-quality

samples. These correlations will be

used to assess the probable chemical

character of water withdrawn from

various rock types throughout the

State. Chemical constituents of the

bedrock aquifers are being mapped

and analyzed in collaboration with

the New England Coastal Basins

National Water-Quality Assessment

(NAWQA) Program.

A better understanding of the sources

and processes of water flow through

fractures in crystalline bedrock is

needed to protect existing water

supplies and to locate high-yielding

sources of water. New methods for

these purposes are being investigated

by the USGS. Advanced geophysical

techniques (such as borehole radar)

were used to locate the nature and

extent of fractures in bedrock in the

towns of Seabrook and Rye, and at

the USGS Mirror Lake fracturedbedrock research site near Thornton.

The USGS is assessing new methods

for collecting high-resolution digital

images of rocks and fractures below

the surface. A new borehole-camera

technique can obtain digital video

images of the inside of a well above

and below the water surface. The

camera captures an image of the

borehole wall (fig. 3). The images

provide data that can be used to

describe the rock type(s) and fractures

in the boreholes, identify on-site

contamination, and aid in planning

for the collection and interpretation of

other geophysical data.

Topographic Mapping

USGS topographic maps of New

Hampshire’s White Mountain National Forest are scheduled for

revision in 1999. In an agreement

between the USGS and the U.S.

Forest Service (USFS), the USFS will

update the maps to show additional

features required for national forest

management. The source images for

these map revisions are digital

orthophoto quadrangles (DOQ’s) that

were produced from aerial photographs taken from 1992 through

1994. These DOQ’s of the White

Mountain National Forest are available to the public from the USGS.

As part of the National Aerial

Photography Program (NAPP), the

USGS obtained new black-and-white

aerial photographs of southern New

Hampshire in the spring of 1998. The

collection of photographs for the

remainder of the State is scheduled

for 1999. NAPP photographs also are

available to the public through the

USGS.

Many of the New Hampshire

1:24,000-scale and 1:25,000-scale

topographic maps are scheduled to be

revised during the next several years.

The USGS plans to work with State

and Federal agencies and Earth

Science Corps volunteers to improve

map content.

Biological Diversity

An important issue in the northeastern United States is how best to

allocate limited resources for land

conservation to maintain diverse plant

and animal populations. In New

Hampshire, USGS scientists are

constructing computer-based models

to predict distributions of vertebrates

and to determine the degree of

protection through land conservation

that is needed for regions of high

vertebrate diversity. Digital maps

describing land-cover patterns,

vertebrate species distributions, and

conservation areas are being used as

tools to help provide critically needed

information on relations between the

distribution of terrestrial vertebrates

and habitats in the region. The results

of the project may assist government

officials and land managers in

making sound decisions for land

conservation. The work is being

supported by the New Hampshire

Fish and Game Department and the

U.S. Fish and Wildlife Service.

Water Quality

In 1991, the USGS began the

NAWQA Program to describe the

quality of the Nation’s water resources, and to identify the natural

and manmade factors that affect it.

The program provides information

that is useful to water-resource

policymakers and managers at

National, State, and local levels. Parts

of central and eastern New Hampshire are included in the 22,900-

square-mile New England Coastal

Basins NAWQA study area, which

also encompasses western and central

Maine, eastern Massachusetts, and

most of Rhode Island. In New

36.740

36.760

36.780

36.800

36.820

36.840

36.860

36.880

36.900

36.920

36.940

36.960

36.980

37.000

37.020

37.040

S W N E S

Fracture

N26°E, 46°E

DEPTH, IN METERS BELOW TOP OF CASING

Figure 3. A digital optical image that

represents an “unrolled” 360-degree

scan of the borehole wall.
New Hampshire

Hampshire, this area includes the

drainage basins of the Merrimack,

Androscoggin, and Saco Rivers, as

well as the smaller coastal drainage

basins. A 3-year effort of intensive

field-data collection began in 1998

with the collection of streambed

sediment, fish tissue, and water

samples. The amount of nutrients

flowing to coastal waters from the

major rivers in eastern New England

and the influence of various levels of

urbanization on water quality in

streams and aquifers and on stream

ecology will be assessed by this

monitoring.

As part of the effort, existing groundwater-quality data were analyzed to

determine if concentrations of arsenic

in ground water—at levels of concern

to public health—are related to

regional geology. The USGS compared arsenic data from 800 publicsupply wells in eastern New England

and found that arsenic was present in

more than 46 percent of wells drilled

in metamorphic rocks that contain

appreciable amounts of calcium

carbonate. In contrast, arsenic was

detected in only 22 percent of wells

drilled in other rock types (fig. 4). A

better understanding of the potential

effect of regional geology on groundwater quality will help water managers in siting wells that comply with

U.S. Environmental Protection

Agency (EPA) drinking-water

standards.

The USGS, in cooperation with the

NHDES and the EPA, is studying the

movement and degradation of chemical (tetrachloroethylene) contamination in parts of a glacial-drift rivervalley aquifer in Milford (fig. 5). The

aquifer is an important source of

water for commercial and State fish

hatcheries, supplying more than

2 million gallons of water per day

(Mgal/d). Before the contamination

was identified, the aquifer had

supplied more than 1 Mgal/d to two

municipal water-supply wells.

Through extensive monitoring of

contaminant levels and the modeling

of ground-water flow, the USGS is

providing information to the State

and EPA to help assess and improve

the design and operation of the

remediation effort.

A new collaborative study between

the USGS and the University of New

Hampshire will examine the inflow of

ground water, nutrients, and contaminants to the Great Bay Estuary in

southeastern New Hampshire. Factors

such as water use, land use, and

ground-water flow affect the amount

and quality of ground and surface

water discharged to the Bay. The

quantity and quality of ground water

flowing into the Bay and the effects

of this influx of fresh water on marine

environments and ecosystems have

not been studied previously. The

study results will be used to determine the extent to which ground

water is a factor in determining the

overall water quality of this estuarine

system.

Water Information

The amount of water in New

Hampshire’s rivers, streams, lakes,

and reservoirs is measured and

monitored by the USGS hydrologic

data-collection program. These data

are used for

• forecasting floods and droughts

• flood warning and flood-plain

management

• water-resources planning

• designing and operating projects

for water supply, hydroelectric

power, flood control, and pollution

control

• designing bridges and culverts, and

• hydrologic research.

Long-term records are needed to

evaluate the responses of hydrologic

systems to natural climatic variations

and human-induced stresses so that

potential problems can be defined

early and appropriate planning and

management actions can be taken by

local and State agencies. Streamflow

monitoring also provides baseline

Figure 5. Aquifer boundary, groundwater withdrawal locations, and the

extent of contaminant plume in

Milford.

0 0.5 MI

0 0.5 KM

NEW HAMPSHIRE

Concord

Milford

State Fish

Hatchery Commercial

Fish Hatchery

Contaminant

source area

100

10

1,000

Streamflow direction

Souhegan River

EXPLANATION

10

Boundary of aquifer

Line of equal total

 volatile organic

 concentration in parts

 per billion (ppb)

Former municipal

 well (1988)

Withdrawal well

Direction of

 contaminant flow

Figure 4. Types of rock with the

percentage of wells where arsenic

concentrations exceeded a

detection limit of 5 micrograms per

liter or greater in the New England

Coastal Rivers Basin study area.
Printed on recycled paper

USGS office locations USGS State Representative

The USGS has 44

employees in 

New Hampshire

Pembroke

361 Commerce Way

Pembroke, NH 03275-3718

(603) 226-7800

FAX (603) 226-7894

USGS Home Page

http://www.usgs.gov

Reports and products

1-888-ASK-USGS

data on the flow characteristics of

rivers and streams. In New Hampshire, surface-water data are collected

(fig. 6) from a network of 52 stations,

and a ground-water-monitoring

network provides monthly waterlevel data for 28 wells. Records are

published monthly and annually. The

network is operated by the USGS, in

cooperation with the NHDES, U.S.

Army Corp of Engineers, several

towns, municipalities, and utility

companies.

Real-time streamflow data, by way of

satellite and telephone telemetry, are

available on the World Wide Web for

37 locations in New Hampshire at:

http://nh.water.usgs.gov

This real-time streamflow information is critical for the flood forecasting and response activities of the

National Weather Service, the New

Hampshire Office of Emergency

Management, and other State and

local officials.

Changing patterns in water use

require that available supplies and

demands be carefully evaluated.

Without adequate information,

decisionmakers are not equipped to

address critical and competing

demands related to water supply,

hydropower, snowmaking, water

quality, and the potential effects of

streamflow withdrawals on ecosystems. In 1995, 450 million gallons of

freshwater were used in New Hampshire (fig. 7).

The USGS, in cooperation with the

NHDES, Water Division, is working

to improve the State’s water-use

information. Completion of a statewide water-use data base is planned

for 1999. This data base will include

site-specific data, as well as compilations at the county and major drainage-basin levels. The data-basemanagement system permits water to

be tracked from the point of withdrawal to the point of return into the

environment. These water-use data

will be available to Federal and State

agencies, educators, consultants, and

other organizations or individuals

concerned with water resources.

Wildlife

A concern about the decline of the

American woodcock during the last

three decades across most of eastern

North America has encouraged USGS

scientists to study the demographics

and habitat requirements of the

popular game bird. In New Hampshire, the research is being carried out

in cooperation with the U.S. Fish and

Wildlife Service (USFWS), the New

Hampshire Fish and Game Department, Dartmouth College, the Wildlife Management Institute, and the

Ruffed Grouse Society. Two separate

woodcock populations are recognized

and managed by the USFWS. Both

populations have dwindled since the

early 1970’s, with a greater drop in

the eastern region (2.5 percent per

year) than in the central region (1.6

percent per year). To understand how

habitat modification is affecting the

populations, USGS biologists are

studying sources of mortality, survival rates, and patterns of woodcock

movement and habitat use. Results of

these studies will help management

agencies set harvest regulations and

identify beneficial forest management

practices. The goal of the Federal

American Woodcock Management

Plan is to stabilize and increase

woodcock populations to 1985 levels

by the year 2005.

Figure 6. A technician is preparing to

measure streamflow by lowering a

current meter from a cable car

suspended over a river in New

Hampshire.

 Figure 7. Total freshwater use by

category in New Hampshire (1995).

Thermoelectric

51 percent

Commercial

11 percent

Industrial 13 percent

Mining 2 percent Agricultural 

1 percent

Domestic 20 percent

Other 

1 percent

Total does not equal 100% due to rounding.