Water Quality in the

Hudson River Basin

New York and Adjacent States, 1992–95

U.S. Department of the Interior

U.S. Geological Survey Circular 1165

science for a changing world
A COORDINATED EFFORT

Chief, NAWQA Program

U.S. Geological Survey

Water Resources Division

12201 Sunrise Valley Drive, M.S. 413

Reston, VA 20192

FOR ADDITIONAL INFORMATION ON THE 

NATIONAL WATER-QUALITY ASSESSMENT (NAWQA) PROGRAM:

Coordination among agencies and organizations is an integral part of the NAWQA Program. We thank the 

following individuals and organizations who contributed data, knowledge, time, and expertise.

Illustrations by Douglas Freehafer, Gary R. Wall, Amanda G. Ramsey, and Gretchen L. Wall

Edited by Anne Finch, Michael Eberle, and Elizabeth B. Palcsak 

Manuscript preparation by Gary R. Wall, Amanda G. Ramsey, and Patricia Lee

Summary of Compound Detections and Concentrations tables were designed and 

 built by Sarah Ryker, Jonathon Scott, and Alan Haggland

Cover photograph - Rondout River at Kingston, N.Y.

Back cover photographs - surface water sampling, Mohawk River at Cohoes, N.Y.,

 electrofishing, Esopus Creek at Allaben, N.Y. 

Hudson River Basin Study Unit, contact:

District Chief

U.S. Geological Survey

Water Resources Division

425 Jordan Road

Troy, NY 12180

Information on the NAWQA Program is also available on the Internet via the World Wide Web. You may 

connect to the NAWQA Home Page using the Universal Resources Locator (URL):

http://wwwrvares.er.usgs.gov/nawqa/nawqa_home.html

The Hudson River Basin Study Unit’s Home Page is at URL:

http://ny.usgs.gov/projects/hdsn/

American Museum of Natural History

Cornell University 

Cornell University Cooperative 

 Extension

Freshwater Institute at Rensselaer 

Polytechnic Institute

General Electric Company

Hudsonia

Hudson River-Black River Regulating 

District

Hudson River Foundation

Hudson River National Estuarine 

Research Reserve

Hudson Valley Regional Council

Institute of Ecosystem Studies

New York Botanical Garden

New York City Department of Environmental Protection

New York Sea Grant

New York State Canal Corporation

New York State Department of Environmental Conservation

New York State Department of Health

New York State Department of State 

Coastal Resource Management

New York State Geological Survey

New York State Museum

Rensselaer Polytechnic Institute

River Watch Network, Inc.

Simon’s Rock College

State University of New York at Albany

Suffolk County, N.Y.

Thatcher Research Associates, Inc.

The Nature Conservancy

U.S. Army Corps of Engineers

U.S. Department of Agriculture

U.S. Environmental Protection Agency, 

Region II

U.S. Fish and Wildlife Service

Water Resources Research Institute at 

Cornell University

Westchester County, N.Y.

Steven Anderson, Montgomery 

County Soil Conservation District

Robert W. Bode, Margaret A. Novak, 

and Lawrence E. Abele, New York 

State Department of Environmental Conservation (NYSDEC) Division of Water, Stream 

Biomonitoring Unit

Richard Bopp, Rensselaer Polytechnic Institute, Department of Earth 

and Environmental Sciences

Robert Crowe and other landowners 

who permitted access to stream 

and well sites on private property

Robert A. Daniels, New York State 

Museum, Biological Survey

Larry Rosenmann, NYSDEC Division of Pesticides and Radiation

Ronald Sloan, NYSDEC Division of 

Fish and Wildlife
U.S. GEOLOGICAL SURVEY CIRCULAR

Water Quality in the Hudson River Basin, 

New York and Adjacent States,1992–95

1165

By Gary R. Wall, Karen Riva-Murray, and Patrick J. Phillips

CONTENTS

National Water-Quality Assessment 

Program ........................................................ 1

Summary of major issues and findings ........ 2

Environmental setting and hydrologic 

conditions ...................................................... 4 

Major issues and findings............................... 6

Water-quality conditions in a

national context ............................................ 16

Study design and data collection................... 20

Summary of compound detections and 

concentrations .............................................. 22

References ......................................................... 28

Glossary............................................................. 29
Library of Congress Cataloging in Publications Data

The use of firm, trade, and brand names in this report is for identification purposes only and

does not constitute endorsement by the U.S. Government

 

Free on application to the

U.S. Geological Survey

Information Services

Box 25286 Federal Center

Denver, CO 80225

U.S. DEPARTMENT OF THE INTERIOR

BRUCE BABBITT, Secretary

U.S. GEOLOGICAL SURVEY

Thomas J. Casadevall, Acting Director

Water quality in the Hudson River Basin, New York and adjacent states, 1992-95

by Gary R. Wall ... [et al.].

 p. cm. -- (U.S. Geological Survey circular ; 1165)

Includes bibliographical references (p. )

ISBN 0-607-89232-3

1. Water quality--Hudson River Watershed (N.Y. and N.J.)

I. Wall, Gary R. (Gary Robert), 1967- . II. Series.

TD225.H8W38 1998

363.739’42’09782--dc21 98-13595

1998
U.S. Geological Survey Circular 1165 1

NATIONAL WATER-QUALITY ASSESSMENT PROGRAM

Began in 1991

Began in 1994

Began in 1997

Not scheduled yet

EXPLANATION

Knowledge of the quality of the Nation's streams and aquifers is important because

of the implications to human and aquatic health and because of the significant costs

associated with decisions involving land and water management, conservation, and

regulation. In 1991, the U.S. Congress appropriated funds for the U.S. Geological

Survey (USGS) to begin the National Water-Quality Assessment (NAWQA) Program

to help meet the continuing need for sound, scientific information on the areal extent

of the water-quality problems, how these problems are changing with time, and an

understanding of the effects of human actions and natural factors on water quality

conditions. 

The NAWQA Program is assessing the water-quality conditions of more than 50 of

the Nation's largest river basins and aquifers, known as Study Units. Collectively,

these Study Units cover about one-half of the United States and include sources of

drinking water used by about 70 percent of the U.S. population. Comprehensive

assessments of about one-third of the Study Units are ongoing at a given time. Each

Study Unit is scheduled to be revisited every decade to evaluate changes in waterquality conditions. NAWQA assessments rely heavily on existing information collected by the USGS and many other agencies as well as the use of nationally consistent study designs and methods of sampling and analysis. Such consistency simultaneously provides information about the status and trends in water-quality conditions

in a particular stream or aquifer and, more importantly, provides the basis to make

comparisons among watersheds and improve our understanding of the factors that

affect water-quality conditions regionally and nationally. 

This report is intended to summarize major findings that emerged between 1992

and 1995 from the water-quality assessment of the Hudson River Basin Study Unit

and to relate these findings to water-quality issues of regional and national concern.

The information is primarily intended for those who are involved in water-resource

management. Indeed, this report addresses many of the concerns raised by regulators,

water-utility managers, industry representatives, and other scientists, engineers, public officials, and members of stakeholder groups who provided advice and input to the

USGS during this NAWQA Study-Unit investigation. Yet, the information contained

here may also interest those who simply wish to know more about the quality of water

in the rivers and aquifers in the area where they live. 

 Robert M. Hirsch, Chief Hydrologist

“The Hudson River Basin 

NAWQA program has 

provided the Department 

with crucial information 

and a solid monitoring 

foundation, to create our 

own statewide pesticide 

monitoring program. It is 

our expectation that 

expansion of the 

NAWQA work to 

include other important 

areas of New York State 

will enable us to 

successfully meet all 

State and Federal 

monitoring requirements 

and provide the 

Department with the data 

we need to make 

responsible pesticide 

registration decisions.” 

Larry Rosenmann -

New York State Department of

Environmental Conservation,

Division of Pesticides and

Radiation

“The NAWQA program 

has shown itself to be 

capable of generating 

high quality data of direct 

benefit to State agencies. 

NAWQA has provided 

the model for how 

different programs should 

work together and 

benefit from each other’s 

research.”

Robert Bode -

New York State Department of

Environmental Conservation,

Division of Water
2 Water Quality in the Hudson River Basin, New York and Adjacent States, 1992-95

SUMMARY OF MAJOR ISSUES AND FINDINGS

STREAM-BOTTOM SEDIMENT - Stream-bottom sediments in some 

urban streams and at some sites on large rivers in the Hudson River 

Basin have elevated concentrations of metals, polychlorinated 

biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs) 

compared to results from sites in other NAWQA Study Units; some of 

these concentrations exceed federal or state water-quality standards.

The Sawmill River at Yonkers, the most densely populated urban site studied 

in the Hudson River Basin, had some of the highest concentrations of metals 

in stream-bottom sediments among NAWQA sites nationwide (p. 6). Highly 

urban areas are the source of most of the metals in streams draining urban and 

large watersheds.

The distribution of chromium concentrations in Hudson River stream-bottom sediments is consistent with previous 

observations of a point source of heavy metals on the upper Hudson River (p. 6-7).

Concentrations of lead, mercury, and zinc in stream-bottom sediments were positively related to the percentage of urban 

land within the watershed. Many of the metals concentrations in sediment from urban sites exceeded the proposed 

New York State Department of Environmental Conservation (NYSDEC) Severe Effect Levels for stream-bottom 

sediment (p. 6-7).

NYSDEC proposed Severe Effect Levels for metals were not exceeded in any stream-bottom-sediment samples from 

sites in forested or agricultural watersheds (p. 6).

PCBs persist in stream-bottom sediment despite being banned more than 20 years ago. PCB concentrations in Hudson 

River bottom-sediments exceeded the proposed NYSDEC criteria for human health bioaccumulation at all sites at which 

they were detected (p. 8-9) and were among the highest at NAWQA sites nationwide (p. 16).

Spatial patterns in concentration of PAHs within the basin corresponded with factors such as location in the Hudson 

River Basin and proximity to urban areas (p. 8).

FISH TISSUE - Although banned for more than 20 years, PCBs, DDT and (or) its breakdown products were 

detected in composites of whole fish from many sites, and were most frequently detected in samples from 

sites on large rivers and in small urban watersheds.

PCB concentrations in composite whole-fish samples from the Hudson River at Poughkeepsie and the Mohawk River 

near Utica exceeded the Food and Drug Administration (FDA) action level of 2,000 micrograms per kilogram of edible 

flesh (fillets). This indicates the potential for elevated concentrations in edible portions, and has prompted further 

investigation and fish-consumption advisories for selected species in a 40-mile section of the Mohawk River. 

Consumption advisories remain in effect for most species in parts of the Hudson River (p. 9).

Concentrations of organochlorine compounds other than PCBs in composites of whole fish were below FDA action levels 

for edible flesh at all sites sampled. This suggests that concentrations in edible portions of these samples would not have 

exceeded FDA action levels for those compounds (p. 8).

PCBs, DDT and its breakdown products, and chlordane were more likely to be detected in fish tissue than in streambottom sediments at sites where both whole fish samples and stream-bottom sediment samples were collected. This 

suggests that bioaccumulation through the food chain occurs even where these compounds cannot be detected in streambottom sediment (p. 8).

STREAM ECOLOGY - Most agricultural and urban streams studied supported a smaller number of 

intolerant fish and macroinvertebrate species than that expected in streams with undisturbed chemistry 

and (or) habitat.

Fish communities at the three most highly urbanized sites sampled were numerically dominated by a single fish species. 

Intolerant species were entirely absent or rare at these sites (p. 10-11). 

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U.S. Geological Survey Circular 1165 3

SUMMARY OF MAJOR ISSUES AND FINDINGS

Stream-habitat degradation was severe at channelized sites in cities and was moderate at agricultural sites where streambank vegetation had been removed and where streambank erosion had occurred (p. 11, 17). Benthic macroinvertebrate 

groups sensitive to suspended and (or) deposited sediment appear to be replaced by sediment-tolerant species in streams 

with streambank erosion (p. 11). 

Urban streams in some densely populated watersheds with undisturbed streambanks supported larger numbers of fish 

species intolerant to impaired water quality than urban streams with disturbed streambanks (p. 11, 17). The presence of 

an extensive, forested buffer zone on and adjacent to streambanks appears to mitigate potential adverse effects of urban 

and agricultural land use on fish communties.

SURFACE-WATER AND GROUND-WATER CHEMISTRY - The concentrations of dissolved pesticides and 

nutrients in samples from most sites in the Hudson River Basin were below the national median 

concentrations. In some samples, however, water-quality standards or guidelines for these and other 

constituents were exceeded.

In general, concentrations of pesticides and other dissolved constituents are low in ground water and surface waters of the 

Hudson River Basin. Although 18 different pesticides or pesticide-degradation compounds were detected in three streams 

sampled at least monthly over 2 years (total of 108 samples), only 2 samples contained a pesticide concentration higher 

than a U.S. Environmental Protection Agency (USEPA) drinking-water standard; however, only 12 of the 18 compounds 

have established standards (p. 12).

Atrazine was the most commonly detected pesticide in surface water and ground water and was found in nearly every 

sample in which any other pesticide was detected (p. 13-14). Atrazine is one of the most commonly used pesticides in the 

basin, hence the frequency of its detection with other pesticides is not unusual.

Although pesticides were detected throughout the year, pesticide concentrations in streams were generally highest 

immediately after field application and during the first storm runoff following application (p. 13).

In a spring 1994 survey of 46 stream and river sites in the Hudson River Basin, 32 percent of pesticide detections were 

insecticides in streams draining watersheds with a significant percentage of urban land. This rate of detection was 

3.5 times that of streams draining agricultural or mixed-land-use watersheds. Fifty percent of all insecticide detections 

were in streams draining urban areas, a disproportionate amount given that only 22 percent of the streams sampled 

drained these areas (p. 14). The percentage of insecticide detections in urban areas reflects the use of these products on 

lawns and similar non-agricultural areas.

Pesticides were detected in ground water from 25 percent of wells used for domestic water supply, no more than 

2 pesticides were detected at any individual well (p. 14), and none of these detections were at concentrations above any 

available USEPA drinking-water standard.

Nitrate concentration in ground water indicated the effects of human activity (concentration greater than 3.0 mg/L) in 

38 percent of the samples from beneath agricultural fields, in 23 percent of the samples from beneath urban/residential 

areas, and in 16 percent of the samples from domestic wells (p. 15).

Nitrate concentrations in ground water beneath agricultural areas were above the national median for such areas (p. 18). 

Two of sixteen wells sampled (12.5 percent) had concentrations above the USEPA Maximum Contaminant Level (MCL) 

(10 mg/L), however none of the wells was used as a source of drinking-water (p. 15).

About one-third of the ground-water samples from beneath urban/residential areas contained at least one volatile organic 

compound, but none of the concentrations exceeded any available water-quality standards (p. 19).

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4 Water Quality in the Hudson River Basin, New York and Adjacent States,1992-95

ENVIRONMENTAL SETTING AND HYDROLOGIC CONDITIONS

Albany

New York 

Glens Falls

Utica Amsterdam

Poughkeepsie

Newburgh

HoosicRi ver

Hudson River

Schoharie Creek

Lake

Sacandaga 

revi Rlli kll a W

Mohawk River

LAND USE MAJOR AQUIFERS

EXPLANATION

MAJOR RIVERS AND STREAMS

0 25 50

10 20 30 MILES

KILOMETERS

Forested

Agricultural

Urban/residential

Water

Other

Land use

0

FORESTED

AGRICULTURAL

URBAN/

RESIDENTIAL

WATER

OTHER

0

10

20

30

40

50

60

70

80

PERCENTAGE OF BASIN

62.3%

24.9%

7.8%

2.6% 2.4%

The Hudson River Basin encompasses about 

13,300 mi2

 (square miles) in eastern New York and 

parts of Vermont, New Jersey, Massachusetts, and 

Connecticut. About 62.3 percent of the Hudson River 

Basin is forested, 24.9 percent is agricultural land 

(including row crops, pasture, vineyards, and 

orchards), 7.8 percent is urban (including commercial 

and industrial land) and residential land, 2.6 percent 

is open water, and 2.4 percent is classified as “other.” 

Agricultural land is predominant in the Mohawk and 

Wallkill River subbasins and in some areas east of the 

Hudson River. Nearly all of the major urban and 

industrial centers in the basin are concentrated within 

a few miles of the Hudson and Mohawk Rivers. 

The headwaters of the Hudson River are in the 

central Adirondack Mountains. The largest tributary 

to the Hudson is the Mohawk River, which nearly 

doubles the flow of the Hudson where they meet at 

Cohoes, N.Y.

Major aquifers in the basin consist mainly of sand 

and gravel and occupy many of the lowland areas 

adjacent to streams and rivers. Many domestic wells 

rely on ground water from fractures in bedrock, but 

no bedrock formations in the basin are considered 

major aquifers. 

More than 80 percent of the people in the Hudson 

River Basin are served by public drinking-water 

supplies that are obtained largely from surface-water 

sources. Domestic supplies, which serve the 

remaining population, are almost entirely dependent 

on ground-water sources. The single largest water 

withdrawal in the basin is for power generation.

0

500

1,000

1,500

2,000

2,500

3,000

3,500

0

10

20

30

40

50

60

70

80

90

100 Ground water

Surface water

Population served, 

 in thousands

(3,842)

(705)

(3,842)

TOTAL

THERMOELECTRIC

IRRIGATION

AND LIVESTOCK

INDUSTRIAL

AND MINING

COMMERCIAL

DOMESTIC

PUBLIC

SUPPLYSUPPLY

PERCENTAGE OF TOTAL

WATER WITHDRAWALS

WATER WITHDRAWALS,

IN MILLIONS OF GALLONS PER DAY
U.S. Geological Survey Circular 1165 5

ENVIRONMENTAL SETTING AND HYDROLOGIC CONDITIONS

Precipitation and streamflow in 1993-94 were above normal 

throughout the Hudson River Basin and resulted in higher than 

normal ground-water levels for the summer months of 1993 and 

1994. In contrast, precipitation, streamflow, and ground-water 

levels were below normal during most of 1995. 

Drought conditions in 1995 were particularly noticeable in the 

Mohawk River at Cohoes, where streamflows for April, May, and 

September 1995 were the lowest on record. Drought conditions 

probably resulted in lower than normal amounts of nutrient, 

pesticide, and sediment runoff from streams in the spring and 

summer of 1995. High flow, Mohawk River at 

Cohoes Falls, Cohoes, N.Y. 

10,000

20,000

30,000

40,000

0

0

10,000

20,000

30,000

40,000

50,000

60,000

70,000

Mean monthly for period of record

Monthly mean during sampling period

1992 1994 1995 1993

1992 1994 1995 1993

STREAMFLOW, IN CUBIC FEET

PER SECOND

44

42

40

38

36

34

32

30

WATER TABLE DEPTH, IN FEET

BELOW LAND SURFACE

Historical monthly water level (1982-95)

Daily mean streamflow during

sampling period

1992 1994 1993

0

1

2

3

4

5

6

7

8

9

PRECIPITATION, IN INCHES

Maximum

Mean

Minimum

Historical monthly precipitation (1950-95)

Monthly mean precipitation

during sampling period

The 1995 drought 

resulted in low streamflow, 

precipitation, and groundwater levels in the Hudson 

River Basin

GROUND WATER LEVELS - East Greenbush, N.Y., 

observation well (Re 703)

STREAMFLOW - Mohawk River at Cohoes, N.Y. 

PRECIPITATION - Albany County Airport 

(Data from National Weather Service)

1995

ODF A J AODF A J AODFA J A

ODF A J AODF A J AODFA J A

ODF A J AODF A J AODFA J A

ODF A J AODF A J AODFA J A

Daily mean water level observed during sampling period

Maximum

Mean

Minimum

Huds on River

Mohawk Ri ver

Low flow, Mohawk River at 

Cohoes Falls, Cohoes, N.Y. 

Photograph by Charles Strain, USGS Photograph by Christopher Ryan, USGS
6 Water Quality in the Hudson River Basin, New York and Adjacent States, 1992-95

MAJOR ISSUES AND FINDINGS

Metals in Stream-Bottom Sediments

Stream-bottom sediments were collected at 44 sites on 35 

streams and rivers across the Hudson River Basin from 

August 1992 through October 1994 for analysis for trace 

elements and organic contaminants. The purpose was to 

(1) assess the presence of these constituents, and (2) detect 

any correlation between land use in the watersheds and the 

chemical quality of bottom sediment in the streams that drain 

them. This section discusses seven selected heavy metals that 

have been shown to adversely affect the quality of streambottom sediments and, thus, pose a risk to the surrounding 

aquatic ecosystem. The New York State Department of 

Environmental Conservation (NYSDEC) has proposed 

concentration screening criteria for metals in stream-bottom 

sediments (New York State Department of Environmental 

Conservation, 1994) (table 1) to indicate the concentrations 

that could affect aquatic organisms. Additional testing is 

generally needed to assess what actual risks to the 

environment are present, however. Sampling sites were 

classified according to the predominant land use in the 

watershed to correlate stream-bottom sediment quality with 

the principal land use in the watershed (fig. 1). Land-use 

categories were defined as follows: 

Urban sites were those in watersheds that are more than 10 

percent urban land and whose population density exceeds 

200 per square mile. 

Large-mixed sites were those in watersheds that encompass 

more than 500 mi2

 but have no single predominant land use 

(that is, less than 35 percent agricultural, less than 90 percent 

forested, and less than 10 percent urban).

Forested sites were those in watersheds that were more than 

90 percent forest. 

“Other” sites are those in agricultural or small (less than 

500 mi2) mixed-land-use watersheds.

Stream-bottom sediment in the Sawmill River at Yonkers, 

the most highly urbanized site (highest population density) 

among those surveyed, had the highest concentrations of 

cadmium (6.9 μg/g, micrograms per gram), copper 

(410 μg/g), mercury (1.4 μg/g), nickel (72 μg/g), and zinc 

(980 μg/g). Sediment at the Fall Kill at Poughkeepsie, 

another urban site, had the highest concentration of lead 

(450 μg/g).

Some of the highest chromium concentrations were along 

the mainstem of the Hudson River. Concentrations were 

highest at Stillwater (160 μg/g) and decreased downstream to 

130 μg/g at Waterford and Poughkeepsie and to 110 μg/g at 

Table 1. Screening criteria proposed by New York State Department 

of Environmental Conservation for metals in stream-bottom sediment

[Effect Levels are in micrograms per gram]

Metal

Effect Level*

Lowest Severe

Cadmium 0.6 9.0

Chromium 26 110

Copper 16 110

Lead 31 110

Mercury .15 1.3

Nickel 16 50

Zinc 120 270

0 10 20 30 40 50 60 70 80 90 100

Cadmium

Chromium

Copper

Lead

Mercury

Nickel

Zinc

Urban

Large-mixed

Forested

Other

Urban

Large-mixed

Forested

Other

Urban

Large-mixed

Forested

Other

Urban

Large-mixed

Forested

Other

Urban

Large-mixed

Forested

Other

Urban

Large-mixed

Forested

Other

Urban

Large-mixed

Forested

Other

Maximum

concentration

(μg/g)

PERCENTAGE OF SITES AT WHICH ONE OR 

BOTH PROPOSED CONTAMINATION

CRITERIA (TABLE 1) WERE EXCEEDED

Metal Land-use category

Severe Effect Level

130

160

88

80

410

250

30

53

450

160

33

90

72

38

49

43

980

330

200

250

6.9

1.9

1.0

1.1

.65

.15

.31

1.4

Lowest Effect Level

Figure 1. Percentage of sites at which one or both New York State 

proposed screening criteria for metals contamination in streambottom sediment were exceeded, and maximum concentrations of 

metals by land-use category. Sites in urban and large-mixed 

watersheds had the highest concentrations and often exceeded 

both criteria. *Effect Levels used by NYSDEC represent two risk levels for metals contamination in sediments. (1) A sediment is considered contaminated if 

either criterion is exceeded. (2) The sediment is considered moderately 

affected if only the Lowest Effect Level is exceeded and severely affected if 

both levels are exceeded.
U.S. Geological Survey Circular 1165 7

MAJOR ISSUES AND FINDINGS

Hastings-on-Hudson. The lowest chromium concentrations 

— 28 and 47 μg/g, respectively — were at sites upstream 

from Stillwater, at Luzerne and Hadley, where the Hudson 

River drains mainly forested land. This distribution pattern 

is similar to that observed previously for heavy-metals 

concentrations in upper Hudson River sediments (Frank 

Estabrooks, New York State Department of Environmental 

Conservation, written commun., 1995) and is consistent with 

a known point source of heavy metals between Hadley and 

Stillwater.

In general, metal concentrations in stream-bottom 

sediment were positively correlated with urban land use 

(fig. 2). This relation was strongest for lead, mercury, and 

zinc. No relation was found between watershed size and 

metals concentration, but the large watersheds contain larger 

amounts of urban land, which probably contributed to the 

higher concentrations of some metals at these sites than sites 

in nonurban watersheds.

Proposed metals criteria were exceeded most frequently at 

sites in urban and large mixed-land-use watersheds. The 

proposed Severe Effect Level was exceeded only in urban 

and large watersheds. Sediment from every urban site 

exceeded the Lowest Effect Level for five of the seven metals 

discussed here, and sediment from several of the forested 

watersheds exceeded this criterion for some metals. Metals 

concentrations that exceed the Lowest Effect Level at sites in 

nonurban watersheds that reflect undisturbed conditions 

could also have an adverse effect on aquatic life (New York 

State Department of Environmental Conservation, 1994).

Semivolatile Organic Compounds in 

Stream-Bottom Sediments

Samples of stream-bottom sediments from 33 sites across 

the Hudson River Basin were analyzed for 79 semivolatile 

organic compounds (SVOCs). Of the 79 SVOCs analyzed, 

27 included organic compounds known as polycyclic 

aromatic hydrocarbons (PAHs). PAHs are formed mainly as 

byproducts of combustion, such as fossil-fuel power 

generation, numerous industrial processes, and forest fires 

(Neff, 1979).

Each of the 33 sites was ranked by concentration for each 

PAH. Because PAHs attach chemically to organic carbon, 

and because the amount of organic carbon in stream-bottom 

sediment differs among sites, PAH concentrations were 

carbon adjusted to allow site-to-site comparisons. The sum 

of the individual PAH ranks for each site was in turn ranked 

to give each site a ranking (representing all 27 PAHs). This 

ranking is given in table 2. Although the percentage of urban 

and industrial land use in the watershed upstream from each 

Table 2. Rank of stream-bottom sediment-sampling sites, in order of 

the total rank of 27 carbon normalized PAH concentrations, and 

percentage of urban and industrial land in the watershed above 

each site

[Lowest rank number corresponds to highest concentration rank]

Site 

rank Site name

Percentage of 

watershed

Urban Industrial

1 Hudson River south of Hastings-on-Hudson 8.61 0.16

2 Mohawk River near Utica 11.89 .30 

3 Patroon Creek at Albany 91.43 8.57 

4 Hallocks Mill Brook at Yorktown Heights 67.92 0

5 Woodbury Creek near Highland Mills 36.36 0

6 Hudson River at Waterford 3.64 .05 

7 Saw Mill River at Yonkers 84.71 .41 

8 Mohawk River at Fonda 5.29 .08 

9 Haviland Hollow Brook near Putnam Lake .81 0

10 Peekskill Hollow Cr at Van Cortlandtville 35.00 .21 

11 Mohawk River near Little Falls 6.96 .13 

12 Hudson River at Poughkeepsie 7.03 .14 

13 Kisco River below Mount Kisco 38.07 1.70 

14 Coeymans Creek near South Bethlehem 8.66 .60 

15 Hoosic River below Williamstown 12.06 .20 

16 Lisha Kill northwest of Niskayuna 77.42 1.94 

17 Fishkill Cr at Stormville Rd nr Hopewell Jct 8.62 0

18 Fall Kill at Poughkeepsie 28.88 .53 

19 Mohawk River at Cohoes 6.93 .13 

20 Schoharie Creek at Esperance 2.21 0

21 Kinderhook Creek at Rossman 8.16 .06 

22 Canajoharie Creek near Canajoharie 1.17 0

23 Hoosic River near Eagle Bridge 8.74 .08 

24 Wappinger Creek near Wappingers Falls 6.28 .05 

25 Rondout Creek at Rosendale 3.35 .10 

26 Claverack Creek at Claverack 11.31 0

27 Esopus Creek at Allaben 1.57 0

28 Moses Kill near Fort Miller .74 0

29 Batten Kill at Battenville 1.11 0

30 Hudson River at Stillwater 2.18 .02 

31 Hudson River south of Lake Luzerne 1.09 0

32 West Canada Creek at Nobleboro 0 0

33 Wallkill River at Gardiner 10.64 .03 

0.01

0.1

1

10

0.1 1 10 100

PERCENTAGE OF WATERSHED

OCCUPIED BY URBAN LAND

MERCURY CONCENTRATION,

IN MICROGRAMS PER GRAM

Data from site with substantial 

urbanization, but a low percentage of 

heavy industry 

Data point 

Figure 2. Mercury concentration in stream-bottom sediment in 

relation to the percentage of urban land in watersheds of the 

Hudson River Basin. Streams draining urban areas generally had 

higher concentrations of mercury in stream-bottom sediments than 

nonurban and urban watersheds without heavy industry.
8 Water Quality in the Hudson River Basin, New York and Adjacent States, 1992-95

MAJOR ISSUES AND FINDINGS

site is to some degree linked with the PAH site ranking (for 

example, Patroon Creek at Albany has the highest percentage 

of urban and industrial land and ranks third among sites), no 

overall relation was found between these two factors. This 

lack of correlation is probably attributable to other factors 

that are difficult to quantify, such as geographic location and 

proximity to point sources.

Geographic location — Several high-ranking sites are in the 

southern part of the Hudson River Basin. Three of these — 

Hallocks Mill Brook at Yorktown Heights (site rank 4), 

Woodbury Creek near Highland Mills (site rank 5), and 

Haviland Hollow Brook near Putnam Lake (site rank 9) — 

are among the top 10 but have no industrial activity, and 

most of the urbanization is residential. Although the rank of 

these sites is probably due to extensive urbanization south of 

the Hudson Highlands, the greater precipitation in the 

highlands (fig. 3) suggests that the elevated PAH 

concentrations could be due to PAH deposition in rainwater 

from industrial areas far beyond this watershed.

Proximity to point sources — Statistics based on watershed 

land use may not adequately reflect the weight that 

individual or small-scale discharges deserve with respect to 

certain contaminants, including PAHs. Thus, the difference 

in rank between the Hudson River at Stillwater (site 

rank 30) and the Hudson River at Waterford (site rank 6), 

less than 20 miles downstream, may be caused by a point 

source(s) between these sites. 

PCBs and Organochlorine Pesticides in 

Stream-Bottom Sediments and Fish

Organochlorine compounds, such as the pesticides DDT 

and chlordane and their degradation compounds, and 

industrial compounds such as polychlorinated biphenyls 

(PCBs) have a long history of use in the Hudson River Basin, 

including several well-known point sources of PCBs in the 

upper Hudson River (near Glens Falls, N.Y.). Although use 

of these compounds was banned in the 1970’s, they persist in 

the stream-bottom sediments and biota of the basin. Results 

presented here are based on analyses of stream-bottom 

sediment and whole-fish samples for concentrations of DDT, 

chlordane, 16 other organochlorine pesticides, and PCBs. 

Stream-bottom sediments were collected at 45 sites 

throughout the Hudson River Basin, and whole-fish samples 

were collected at 24 sites. The sites were of three types: (1) 

on large rivers draining watersheds with a variety of land 

uses, (2) on small streams draining watersheds dominated by 

urban land use, and (3) on small streams draining watersheds 

dominated by nonurban land use.

The most commonly detected organochlorine compounds 

in stream bottom-sediment and fish-tissue samples were 

DDT and (or) its degradation compounds, PCBs and 

chlordane and (or) its degradation compounds (fig. 4). The 

percentage of sites at which all three were detected in both 

stream-bottom sediments and fish was greater for large 

watersheds and small urban watersheds than for sites in 

small nonurban watersheds. These compounds were detected 

more often in fish than in stream-bottom sediments at sites 

where both fish and sediment samples were collected. This 

finding indicates that even though the concentration of these 

compounds at some sites is too low to be detected in 

sediments, they may accumulate over time within fish (and 

other organisms) to levels that can be detected. 

Concentrations of PCBs, DDT, and chlordane in streambottom sediments exceeded proposed NYSDEC criteria for 

human health bioaccumulation (New York State Department 

of Environmental Conservation, 1994) at all or most sites at 

which they were detected (Phillips and others, 1997). DDT 

concentration exceeded the proposed stream-bottom 

sediment screening criterion for human health 

bioaccumulation (0.01 μg/g OC, micrograms per gram of 

organic carbon) at 62 percent of the sites sampled; 

concentrations of PCBs exceeded the criteria (0.0008 μg/g 

OC) at 33 percent of the sites sampled; and chlordane 

concentration exceeded the criteria (0.001 μg/g OC) at 29 

percent of the sites sampled. Human health guidelines for 

fish are based on edible portions (fillets) and are not directly 

comparable with the higher concentrations expected in 

 

4

12

18

24

27

33

5 10

25

13

PA

CT

NEW YORK

NJ Long Island Sound

Long Island

17

40

42

42

40

38

44

44

44

44

46

46

46

46

46

46

46

48

48

48

48

48

48

50

50

50

50

50

55

60

42

5 12 24

46 Line of equal annual precipitation, in inches

Sites at which stream-bottom sediment was sampled – number 

within circle corresponds to PAH site rank (table 2)

Site within 

 highest third

 (ranks 1-11)

0

0

10 20

20

MILES

KILOMETERS

9

7

1

EXPLANATION

Site within 

 lowest third

 (ranks 23-33)

Site within 

 middle third

 (ranks 12-22)

Hudson

Highlands

Hudson River Basin

Figure 3. Sites at which stream-bottom sediment was collected 

for PAH analysis in the lower Hudson River Basin. Some of the 

highest PAH concentrations were in streams draining the Hudson 

Highlands. PAHs in these streams may be from industrial areas 

outside the Hudson River Basin and from deposition in rainwater.
U.S. Geological Survey Circular 1165 9

MAJOR ISSUES AND FINDINGS

whole fish. Comparison of whole-fish results with these 

guidelines can help identify sites with potential humanhealth risks, however. PCBs were the only organochlorine 

compound detected in whole-fish samples from any site at 

concentrations above the U.S. Food and Drug 

Administration (FDA) action level (2,000 μg/kg); all of these 

sites were on the Hudson and Mohawk Rivers (see box at 

right).

Concentrations of PCBs, DDT, and chlordane in streambottom sediments and (or) fish tissue from some sites were 

higher than those considered potentially harmful to fish and 

wildlife. Both PCBs and chlordane concentrations in streamFigure 4. Detection of PCBs, DDT compounds, and chlordane 

compounds in fish tissue and stream-bottom sediments in Hudson 

River Basin watersheds. These compounds were generally detected 

more often and at higher concentrations in fish tissue than streambottom sediments.

Figure 5. Percentage of sites at which proposed NYSDEC 

screening criteria for at least one organochlorine compound in fish 

tissue and stream-bottom sediment were exceeded. Large and 

small urban watersheds regularly exceeded these criteria in fishtissue and stream-bottom sediment.

PCBs in Hudson and Mohawk River Fish

High concentrations of PCBs in fish from parts of the 

Hudson River have been well documented by NYSDEC 

and others. (See reviews in Armstrong and Sloan, 1987; 

and Limburg and others, 1986.) In 1976 restrictions were 

placed on commercial and recreational fishing in the 

Hudson River downstream from Hudson Falls, in 

response to contamination from PCBs. Although fishing 

is currently permitted in parts of the Hudson River, New 

York State Department of Health advisories to “eat none” 

or to “eat no more than one meal per month” remain in 

force for most species (New York State Department of 

Health, 1997).

Concentrations of PCBs in whole-fish samples from 

the Hudson River at Poughkeepsie and from several 

Mohawk River sites downstream from Utica exceeded 

the FDA action level of 2,000 μg/kg. Although the action 

level is based on edible tissue, not the whole-fish 

concentrations measured in this study, these exceedances 

suggest a potential hazard that warrants further 

investigation. Results from the Mohawk River samples 

have prompted further investigation of conditions and 

sources of PCBs by New York State, which issued fishconsumption advisories for selected species from about a 

40-mile reach of the Mohawk River between Oneida and 

Herkimer. Concentrations of all other organochlorine 

compounds detected in 

fish tissue were below FDA 

action levels at all sites.

Although fish samples 

were not collected from 

some of the upper Hudson 

River sites with known 

PCB contamination, high 

concentrations of PCBs 

were detected in streambottom sediments from 

these sites. 

Large Small

urban

Small

nonurban 

n=number of sites







10

0



20

30

40

50

60

70

80

90

100

n=12 n=8 

n=7 

n=12 

n=9 

n=21 

TYPE OF WATERSHED

PERCENTAGE OF SITES

EXCEEDING PROPOSED

NEW YORK STATE CRITERIA

Fish

Sediment

0 20 100 101 102 103 104 40 60 80 100

PCBs DDT Chlordane

Watershed

Percentage of all sites having

detectable concentrations*

Median concentration**

EXPLANATION

 

 





3

12

6

12

5

21

3

12

6

12

5

21

3

12

6

12

5

21

8

12

7

12

9

21

8

12

7

12

9

21

8

12

7

12

9

21

Fish tissue

Sediment

Large

Small urban

Small nonurban

Sample Material

n n

n = Number of samples

<

<

<

<

<

<

<

'<' denotes less than the detection limit

NOTE: Site percentages for fish based on 

 various species; median concentration for 

 fish based on white suckers only.

** Units for fish are micrograms per kilogram 

 wet weight in fish tissue; units for sediment 

 are micrograms per kilogram of dry sediment

 Fish

 PCBs 50

 DDT and Chlordane 5 

*Detection limits, in micrograms per kilogram (μg/kg)

Sediment

 50

 1

 





 








10 Water Quality in the Hudson River Basin, New York and Adjacent States, 1992-95

MAJOR ISSUES AND FINDINGS

0

2

4

6

8

10

12

14

EPT INDEX

None

Slight

WATER-QUALITY

IMPAIRMENT 

Severe

Moderate

LAND USE

Forest Urban Agricultural

2 pts.

2 pts.

2 pts.

2 pts.

3 pts.

3 pts.

3 pts.

bottom sediments exceeded proposed NYSDEC criteria for 

wildlife bioaccumulation (New York State Department of 

Environmental Conservation, 1994) at 29 percent of sites. 

Concentrations of PCBs in sediment exceeded the NYSDEC 

criterion for wildlife bioaccumulation at a higher percentage 

of sites in large watersheds and small urban watersheds (both 

67 percent) than in small nonurban watersheds (5 percent). 

Chlordane concentration exceeded the NYSDEC criterion for 

wildlife bioaccumulation at a higher percentage of small 

urban-watershed sites (67 percent) than at large-watershed 

sites or small nonurban sites (33 and 5 percent, respectively). 

Fish-tissue concentrations of PCBs and DDT exceeded the 

Wildlife Protection Criteria (WPC) (Newell and others, 1987) 

at 50 percent and 21 percent of all sites, respectively. PCBs 

exceeded the WPC at a higher percentage of sites in large 

watersheds and small urban watersheds (75 and 57 percent 

respectively) than in small nonurban watersheds (22 percent). 

DDT exceeded the WPC at a higher percentage of sites in 

large watersheds (38 percent) than in small urban and small 

nonurban watersheds (22 and 0 percent, respectively).

Site-to-site differences in concentrations of PCBs and 

organochlorine pesticides in stream-bottom sediment and 

fish tissue corresponded with land use, particularly the 

locations of point sources of PCBs and the historical usage 

patterns of DDT and chlordane. Median concentrations of 

PCBs in both stream-bottom sediments and white sucker 

tissue were highest in large-river samples, followed by the 

small-urban stream samples (fig. 6). Many of these sites are 

downstream from point sources and (or) industrial areas. The 

highest median concentrations of DDT and chlordane in 

stream-bottom sediments and white sucker tissue were in 

samples from sites in small urban watersheds. This 

corresponds with greater use of both of these pesticides in 

urban settings than in agricultural and forested settings 

during the 1970’s (Phillips and Hanchar, 1996; Rod, 1989). 

Fish and Macroinvertebrate Communities 

in Hudson River Tributaries

Benthic macroinvertebrate community samples were 

collected during summer 1993 from riffles in 28 streams, by 

methods described in Bode and others (1996). Samples were 

processed and data analyzed as a joint effort by USGS 

NAWQA and NYSDEC scientists. Comparison of indices 

such as EPT (the number of mayflies, stoneflies, and 

caddisflies, orders Ephemeroptera, Plecoptera, and 

Tricoptera, respectively, in a sample) with established 

NYSDEC water-quality criteria (Bode and others, 1996) 

indicate that most of the sites surveyed show some 

impairment (fig. 7). Invertebrate communities seem to be 

responding to nonpoint sources of sediment, nutrients, and 

pesticides (Murray and others, 1996). The three most 

severely impaired urban sites were in watersheds that drain 

densely populated cities. Chemical and habitat data indicate 

that these sites are affected by sewage and industrial 

influences, as well as channel modification and urban runoff 

(Murray and others, 1996).

Results from a 1995 fish-community survey of 16 streams 

show a positive relation between the percentage of fish 

intolerant to impaired water quality (species such as brook 

trout and sculpin) and the percentage of forested or other 

undisturbed land in the watershed (fig. 8). Sites in cities with 

densely populated watersheds supported few species and few 

or no intolerant species. Most of these sites were numerically 

dominated by a single tolerant species (Butch and others, 

1996). Biota of streams draining watersheds that are largely 

residential-urban, and those draining agricultural 

watersheds, showed a wide range of responses, partly as the 

Figure 7. Invertebrate-community survey results from a USGS 

sampling of 28 streams in the Hudson River Basin. Most streams 

sampled show some impairment. Severe water-quality impairment 

was observed at sites in the most highly developed urban 

watersheds.

CONCENTRATION OF PCBs, IN

MICROGRAMS PER KILOGRAM 

Hudson R. south of Lake Luzerne

Hoosic River nr. Hoosick Falls

Mohawk River nr. Utica

Mohawk River at Frankfort

Mohawk River nr. Little Falls

Schoharie R. east of Central Br.

Wallkill River at Gardiner

Hudson River at Poughkeepsie

Otsquago Creek at Valley Brook

Canajoharie Creek at Ames

Kinderhook Creek nr. Brainard

Claverack Creek at Claverack

Catskill Creek at Oak Hill

Roeliff Jansen Kill nr. Ancram

Esopus Creek at Allaben

Rondout Creek at Rosendale

Wappinger Creek nr. Salt Point

Lisha Kill at Niskayuna

Patroon Creek at Central Ave.

Crum Elbow Creek nr. Hyde Park

Fall Kill at Poughkeepsie

Fishkill Creek at Hopewell Jct.

Haviland Hollow Br. nr. Putnam L.

Sawmill River at Yonkers

101 102 103 104 105

<

<

<

<

<

<

<

<, Below detection limit (50 μg/kg) 

NYSDEC

Wildlife

Protection

Criterion

Large watersheds

Small nonurban

watersheds

Small urban

watersheds

NOTE: Sites are listed in downstream

order within watershed categories

Figure 6. Concentrations of PCBs in whole carp or white suckers 

from 24 sites in the Hudson River Basin. Concentrations were highest 

and often exceeded the Wildlife Protection Criterion in large rivers 

and some urban streams.
U.S. Geological Survey Circular 1165 11

MAJOR ISSUES AND FINDINGS

result of differences in the extent of an undisturbed forested 

buffer zone between the stream and the farms, residences, or 

roads.

Habitat Factors that Affect Stream Biota

In addition to chemical factors that affect fish and 

invertebrate communities, stream-channel features, such as 

streambanks, can affect the stream biota. Streams that 

drained highly populated watersheds but supported relatively 

healthy fish and invertebrate communities generally had 

undisturbed reaches that provided shade, had natural 

channels with pools and riffles, receive cool ground water in 

summer months, and had stable banks.

Benthic-invertebrate data from 23 stream sites indicate 

that many of the sites where suspended-sediment 

concentrations are high during spring runoff have a lack of 

certain organisms sensitive to high concentrations of 

suspended sediment and associated deposition, particularly 

net-spinning caddisflies (Hydropsychidae and 

Philopotamidae) (fig. 9). Tolerant organisms, such as midges 

(Chironomidae), that can burrow into the sediment or that 

have other adaptations to fine sediment were found in 

relatively high numbers.

Habitat alteration is severe in some urban areas, where 

streams are straightened and (or) channelized and natural 

streambank vegetation is replaced with concrete and 

pavement (fig. 10). Streamflows in these channels fluctuate 

widely because water is quickly routed from paved surfaces 

and storm drains to the stream during storms. Some altered 

channels support only a few tolerant fish species because of 

the uniform channel shape and stream-bottom material and 

the absence of backwaters and pools that provide shelter 

during high flows.

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

<10

n=10

n=10

n=3

10 to <100 ≥100

SUSPENDED-SEDIMENT CONCENTRATION,

IN MILLIGRAMS PER LITER

MEDIAN RATIO OF NET-SPINNING

CADDISFLY ABUNDANCE TO

MIDGE ABUNDANCE

n=number of samples

Figure 9. Median ratio of net-spinning caddisfly abundance to 

midge abundance as it relates to suspended-sediment 

concentration during high flows. Exposed streambanks, like that 

pictured above, are common in agricultural and urban areas; these 

banks are susceptable to erosion, and they supply higher than 

normal amounts of sediment to streams. 

0

100

200

300

400

500

1993 1994

OND J FMAM J J AS

Saw Mill River at Yonkers, N.Y.

A

0

200

400

600

800

1000

1200

1400

1600

1993 1994

OND J FMAM J JAS

STREAMFLOW, IN CUBIC FEET PER SECOND

Esopus Creek at Allaben, N.Y.

B

Figure 10. Streamflow and abundance of fish for: (A) “flashy” 

(sharply changing) streamflow that results from urbanization and 

(B) streamflow more typical of undisturbed conditions. Pie charts 

represent the fish community at each site. Number of slices 

indicates the number of species observed; size of slice represents 

the number of individuals in relation to the other species present. 

Blue indicates species tolerance to impaired water quality; red 

indicates intolerance. Channelized conditions and associated 

flashy streamflow likely contributed to the unbalanced fish 

community observed at the Saw Mill River and similar sites. 

0

10

20

30

40

50

60

70

80

90

100

0 10 20 30 40 50 60 70 80 90 100

PERCENTAGE OF FISH SPECIES

INTOLERANT TO IMPAIRED

WATER QUALITY

PERCENTAGE OF FORESTED LAND IN

WATERSHED UPSTREAM FROM SITE

Figure 8. Percentage of intolerant fish species at a site as a function 

of the amount of forested land within the watershed. The absence or 

rarity of fish intolerant to impaired water quality was associated with 

chemical and (or) habitat impairment more often found in developed 

watersheds than in forested watersheds.
12 Water Quality in the Hudson River Basin, New York and Adjacent States, 1992-95

MAJOR ISSUES AND FINDINGS

Pesticides in Streams and Rivers 

Two surveys of streams and rivers were done in the 

Hudson River Basin to assess the presence and distribution 

of pesticides. The first survey consisted of at least monthly 

sampling at three fixed sites (routinely sampled, long-term 

sites) in the Mohawk River subbasin from March 1994 

through September 1995. Two of these sites — Lisha Kill at 

Niskayuna and Canajoharie Creek near Canajoharie — 

represent streams draining urban/residential and agricultural 

land, respectively, and the third — Mohawk River at Cohoes 

— is downstream from the other sites (fig. 11) and 

represents watersheds that contain a wide variety of land 

uses. The second survey was a synoptic sampling (many 

sites sampled once over a short period of time) of 46 sites on 

41 streams and rivers from late May through late June 1994, 

the period during and immediately after which most 

pesticides are applied.

Fixed-Site Results

Streamwater from the three sites sampled (table 3) 

contained 18 pesticides, specifically, 12 herbicides, 2 

herbicide-degradation products, and 4 insecticides (Wall and 

Phillips, 1996b). Only two of the 108 samples collected 

contained any pesticide at a concentration that exceeded a 

drinking-water standard (either a maximum contaminant 

level (MCL) or health advisory level (HA) established by the 

U.S. Environmental Protection Agency (USEPA)); both were 

from Canajoharie Creek. One sample had an atrazine 

(herbicide) concentration of 4.3 μg/L (the MCL is 3 μg/L), 

and the other had a cyanazine (herbicide) concentration of 

2.1 μg/L (the HA for cyanazine is 1 μg/L).

The highest concentrations of 15 of the 18 pesticides 

detected were in samples from either Canajoharie Creek or 

Lisha Kill; nearly all detections of the three remaining 

pesticides (alachlor, 2,6-diethylanaline, and tebuthiuron) 

were at the Mohawk River site. Canajoharie Creek is 

adjacent to farmland where agricultural chemicals are 

applied; therefore, the detection of the agricultural 

herbicides atrazine, cyanazine, metolachlor, 

pendimethalin, metribuzin, and simazine in the highest 

concentrations in the study was not surprising. Similarly, 

the highest concentrations of all four insecticides detected 

were in samples from the Lisha Kill; this watershed 

contains extensive urban and residential lands. The 

Mohawk River receives water from many tributaries 

draining forested, urban, and agricultural lands; therefore, 

the lower concentrations of pesticides in the Mohawk River 

at Cohoes than in Canajoharie Creek or Lisha Kill can be 

attributed to dilution.

Pesticide concentrations were typically highest during the 

first major runoff-producing storm after the pesticide 

application period and were higher in June and July than in 

the rest of the year (Wall and Phillips, 1996a). The highest 

atrazine concentration in Canajoharie Creek was detected 

during the largest summer stormflow, on July 1, 1994 

(fig. 12). Because a stream in a small watershed generally 

responds faster to storm runoff than those in a large basin, 

the large proportion of agricultural land in the Canajoharie 

Creek watershed resulted in a more rapid increase in atrazine 

concentrations, and higher concentrations, here than at the 

two other sites.

Table 3. Pesticides detected among the three Mohawk River 

subbasin fixed sites, March 1994 through September 1995

[Colors indicate where maximum concentration was detected: yellow, 

Canajoharie Creek; red, Lisha Kill; blue, Mohawk River]

Pesticides

detected

Type of 

product1

Concentration 

(micrograms per liter)

Detection 

limit MCL/HA2 Maximum detected

Atrazine H 0.001 3 4.3

Cyanazine H .004 1 2.1

Metolachlor H .002 70 1.3

Carbaryl I .003 700 .86

Diazinon I .002 .6 .55

Deethylatrazine D .002 na .22

α-HCH I .002 na .21

Prometon H .018 100 .071

Pendimethalin H .004 na .035

Metribuzin H .004 100 .033

Terbacil H .007 90 .023

Alachlor H .002 2 .021

Simazine H .005 4 .018

Molinate H .004 na .016

Tebuthiuron H .01 500 .01

Chlorpyrifos I .004 20 .009

EPTC H .002 na .004

2,6-Diethylanaline D .003 na .003

 

Mohawk River

subbasin

Mohawk River

at Cohoes

Mohawk

River

Hudson

R iver

Schoharie Cr.

Basin

boundary

Canajoharie Cr.

near Canajoharie

County

County

Fulton 

Albany County

Saratoga County

Schoharie

County

Schenectady

County

Montgomery 

Sacandaga

Lake

HUDSON RIVER BASIN

0

0 10 KILOMETERS

5 MILES

Lisha Kill 

at Niskayuna

74°

43°

74°30'

42°30'

Rensselaer County

Figure 11. Locations of fixed sites sampled for pesticides from 

March 1994 through September 1995. Canajoharie Creek and 

Lisha Kill were selected to represent conditions in agricultural and 

urban/residential streams, respectively. The Mohawk River at 

Cohoes was selected to represent streams and rivers draining a 

variety of land uses.

1

H, herbicide; I, insecticide; D, degradation compound.

2

MCL, Maximum Contaminant Level; HA, Health Advisory Level.
U.S. Geological Survey Circular 1165 13

MAJOR ISSUES AND FINDINGS

In general, seasonal patterns of pesticides detected over 

the course of the year mimicked those of atrazine. Atrazine 

concentrations at Canajoharie Creek during June and July 

ranged from 0.04 μg/L to more than 1 μg/L — at least double 

the 0.02 to 0.04 μg/L concentrations detected during the 

remainder of the year. Atrazine concentrations in the 

Mohawk River at Cohoes ranged from 0.04 to 0.37 μg/L 

during the growing season (May through August) and were 

less than 0.04 μg/L during the remainder of the year. The 

sample with the highest atrazine concentration at this site 

was also collected in July 1994, about 1 week after the 

maximum atrazine concentration was observed at 

Canajoharie Creek. This delay in peak concentration is not 

surprising, however, in that the Cohoes site is downstream 

from Canajoharie Creek and receives runoff from several 

other small watersheds (some dominated by agricultural 

land). This explains why peak concentrations were delayed 

and why elevated concentrations were sustained for a longer 

period than in Canajoharie Creek. Atrazine was seldom 

detected in the Lisha Kill, and concentrations exceeded 0.01 

μg/L only from mid-May through July.

Pesticides were detected in a higher percentage of 

samples collected during the growing season than in the 

nongrowing season. Most detections during the nongrowing 

season were probably the result of movement of pesticides to 

ground water and their subsequent discharge to streams and 

rivers.

Deethylatrazine, an atrazine-degradation compound, was 

detected more frequently during the nongrowing season than 

the growing season in both Canajoharie Creek and the 

Mohawk River at Cohoes. This probably results from the 

extended period over which the degradation compound 

forms after the parent compound (atrazine) is applied. 

Although the degradation process permits deethylatrazine to 

persist throughout the nongrowing season, concentrations 

are highest during the growing season.

Synoptic Survey Results

Of the 46 synoptic sites sampled, 85 percent had 

detectable concentrations of at least one pesticide, and four 

sites (9 percent) had detectable concentrations of more than 

five pesticides. The Mohawk River at Cohoes site contained 

detectable amounts of eight pesticides or pesticidedegradation compounds, and the Hoosic River at Eagle 

Bridge had detectable amounts of six pesticides. Both sites 

are in large watersheds with a wide diversity of land use. The 

Lisha Kill at Niskayuna site and the West Creek at 

Warnersville site (in urban and agricultural watersheds, 

respectively) each had five detectable pesticides and one 

detectable degradation compound. The amount of 

agricultural land (33 percent of basin) and urban land 

(7 percent of basin) upstream from the Mohawk River site, 

and the size of the 3,500 mi2

 watershed, probably account 

for the large number of pesticides detected in samples from 

this site.

Among the 46 sites sampled, 15 pesticides were detected: 

8 herbicides, 2 herbicide-degradation compounds, and 5 

insecticides (Wall and Phillips, 1996b). The highest 

concentrations of 12 of the 15 pesticides were in streams and 

rivers draining either agricultural or urban land. The most 

frequently detected herbicides were atrazine and metolachlor 

(85 and 67 percent of sites, respectively), and the most often 

detected insecticides were diazinon and carbaryl (30 and 7 

percent of sites, respectively). 

Most of the pesticides detected in the synoptic survey 

were at low concentrations, ranging from 0.002 to 0.05 μg/L. 

The maximum concentration of any pesticide detected was 

1.6 μg/L (for carbaryl), and no concentration exceeded any 

Canajoharie Creek near

Canajoharie

Lisha Kill at Niskayuna

Mohawk River at Cohoes

1994 1995

MAMJ J ASOND J FMAMJ J AS

0.001

0.01

0.1

1

10

0

10,000

20,000

30,000

40,000

50,000

0.001

0.01

0.1

1

10

0

250

500

750

1,000

1,250

1,500

0.001

0.01

0.1

1

10

0

20

40

60

80

100

120

140

160

180

200

STREAMFLOW, IN CUBIC FEET PER SECOND

ATRAZINE CONCENTRATION, IN MICROGRAMS PER LITER

Atrazine concentration

0.001 μg/L or greater

Atrazine concentration

less than 0.001 μg/L 

Figure 12. Atrazine concentration and streamflow at the three fixed 

sites (locations are shown in fig. 11). The highest concentration of 

atrazine and other pesticides generally occurred during the first 

runoff after pesticide application.
14 Water Quality in the Hudson River Basin, New York and Adjacent States, 1992-95

MAJOR ISSUES AND FINDINGS

0 10 20 30 40 50 60 70 80 90 100

Agricultural

Urban

Ground-water surveys:

PERCENTAGE OF SITES WITH DETECTION

Atrazine

Metolachlor

Deethylatrazine

Diazinon

Prometon

Malathion

1994 synoptic survey 

Metribuzin

Land Use

Surface-water survey:

NOTE: See table 3 for detection limits; 

 detection limit for malathion is 0.005 μg/L

Domestic

available MCL or HA. These samples were collected during 

flow conditions that would not normally produce the highest 

annual concentrations, however. Eight of the nine sites where 

atrazine was not detected were in forested and urban 

watersheds; the ninth was at West Kill, northwest of North 

Blenheim, in a small watershed with mixed land use. 

The sites in urban watersheds had the same number of 

pesticides detected as sites in agricultural and mixed-landuse watersheds — nine pesticides in each of the these 

groups. The types of pesticides at a given site correlated 

closely with land use; insecticides accounted for 32 percent 

of all pesticides detected at urban-watershed sites but only 9 

percent of the pesticides detected at sites in agricultural and 

mixed-land-use watersheds (table 4). Among all 46 sites, 50 

percent of the insecticide detections were in streams draining 

urban watersheds, and 4 of the 15 pesticides detected 

(carbaryl, DCPA, prometon, and malathion) were found only 

at sites in urban watersheds. 

Pesticides were detected at only two of the six forested 

watershed sites: West Canada Creek at Nobleboro and East 

Canada Creek at Stratford. Three herbicides (atrazine, 

metolachlor, and cyanazine) and one herbicide-degradation 

compound (deethylatrazine) were found at the West Canada 

Creek site at concentrations equal to or less than 0.012 μg/L, 

and atrazine and metolachlor were detected at the East 

Canada Creek site at concentrations equal to or less than 

0.007 μg/L. Atrazine and other herbicides are not commonly 

used in forested areas; thus, their presence could be the 

result of atmospheric transport from areas where herbicides 

are applied. 

Although the percentages of herbicide detections at sites 

in mixed-land-use watersheds were similar to those sites in 

agricultural watersheds, the concentrations of herbicides 

were generally lower at sites in mixed-land-use watersheds 

than at sites in agricultural watersheds. 

Pesticides in Ground Water 

Three well networks (agricultural, 16 wells; 

urban/residential, 26 wells; and domestic, 49 wells) were 

sampled to assess the occurrence of pesticides in ground 

water. The first two of these networks were designed to 

identify pesticides in shallow ground water (where the water 

table is less than 40 feet below land surface) in agricultural 

and urban/residential parts of the basin; the third represented 

ground water used for domestic water supply. The 

percentage of detections for the seven most commonly 

detected pesticides among the three networks is shown in 

figure 13; for comparison, the ground-water results are 

paired with results of the 1994 synoptic survey of pesticides 

at 46 stream and river sites across the Hudson River Basin.

The highest number of pesticides and the highest 

concentrations were in the 16 agricultural-network wells; 

seven pesticides or pesticide-degradation compounds were 

detected, three of which (atrazine, deethylatrazine, and 

metolachlor) were in samples from more than two of the 

wells. At least one pesticide was detected in 69 percent of the 

agricultural-network wells. Metolachlor and diazinon were 

found in 1 of the 26 urban-network wells; no other urban 

wells were found to contain any pesticides. 

Five pesticides were detected in the domestic-well 

survey, but no more than two pesticides were detected in 

any domestic well. At least one pesticide was detected in 

12 of 49 wells (24.5 percent) used for domestic water 

supply. All concentrations of pesticides in the domestic 

wells were less than 0.3 μg/L except for one detection of 

prometon (1.3 μg/L), a herbicide used to control most 

annual and perennial broadleaf and grassy weeds in nonagricultural areas.

Table 4. Synoptic survey pesticide detections, by watershed land 

use

Watershed land-use 

category and number of sites in each

Number of 

pesticide 

detections

Percentage of detections as

Herbicide and 

herbicide-degradation 

compound

Insecticide

Urban (10) 31 68 32

Agricultural (14) 53 91 9

Mixed (16) 54 91 9

Forested (6) 6 100 0

Figure 13. Detection of seven selected pesticides in three groundwater surveys and in a 1994 synoptic survey of streams throughout 

the Hudson River Basin. Among the ground-water surveys, pesticides 

were most often detected in shallow ground water beneath 

agricultural areas, but detection percentages in streams were 

generally highest.
U.S. Geological Survey Circular 1165 15

MAJOR ISSUES AND FINDINGS

Nitrate in Ground Water and Streams

The networks of urban, agricultural, and domestic 

wells and synoptic stream sites used for pesticide 

sampling also were used to sample for nitrate. Samples 

for pesticide and nitrate analysis were collected 

simultaneously from the wells, but the samples from 

streams were collected during the late summer of 1993, 

during low-streamflow conditions.

Of the 91 ground-water samples collected from the 

three networks, 53 percent had detectable (greater than 

0.05 mg/L as N) concentrations of nitrate; 38 percent of 

the agricultural-network wells had nitrate concentrations 

greater than 3.0 mg/L, a concentration considered by 

Madison and Brunett (1984) to indicate human 

influence. This is not surprising for wells in agricultural 

areas, where fertilizer and manure are applied seasonally. 

Of the 26 wells in the urban/residential network, 23 

percent had concentrations greater than 3.0 mg/L, as did 

16 percent of the wells in the domestic-well network. 

Among the agricultural- and urban/residential-network 

wells where nitrate was detected, nearly half (48 percent) 

had concentrations indicative of human influence.

Among the wells and streams sampled, only 5 of the 137 

samples had detections above the MCL, and all of these 

samples were from wells. Only one domestic-well sample 

had a nitrate concentration above the drinking-water 

standard, and this sample (16 mg/L) was from a dug well 

where ground water was only 6.5 feet below land surface; 

both the open surface of a dug well and the shallow depth to 

water make this well highly susceptible to such 

contamination. None of the wells which exceeded the MCL 

were used for drinking water. 

The highest median concentration (1.30 mg/L) of nitrate 

was in samples from the agricultural wells. The maximum 

concentration of 26 mg/L was in a sample of ground water 

beneath an office park (urban/residential area) in which lawn 

fertilizer probably was applied. Of the stream samples, 93 

percent contained detectable concentrations of nitrate, but 

the highest concentration was only 1.4 mg/L, and the median 

concentration for all the stream sites was 0.35 mg/L.

What is Nitrate?

Nitrate is the form of nitrogen most commonly 

and most easily assimilated by plants. Nitrate forms 

naturally in soil from transformations of nitrogen, 

nitrogen-based fertilizers, manure, or urea. 

Nationwide, nitrate is the most widespread 

contaminant in ground water, and because most 

ground water eventually discharges to surface 

water, nitrate in ground water can pose a potential 

threat to surface-water quality. Direct surface runoff 

of waters from agricultural areas and discharge 

from wastewater treatment facilities can also 

contribute to elevated nitrate concentrations and 

degrade the quality of streamwater.

Human ingestion of water with nitrate 

concentrations in excess of the MCL (10 mg/L) can 

lead to a sometimes fatal blood disorder in infants 

called methemoglobinemia or “blue-baby 

syndrome.” 

0 10 20 30 40 50 60 70 80 90 100

GROUND-WATER SURVEYS

PERCENTAGE OF SITES OR WELLS

 0.05 mg/L

 3 mg/L

 

 10 mg/L

SYNOPTIC

STREAM

SURVEY

(46 sites)

Land Use

Agricultural

(16 wells)

Urban/Residential

(26 wells)

Domestic

(49 wells)

EXPLANATION

Concentration of

 nitrate exceeded

Significance of concentration

 Detection limit 

 Higher concentrations in ground

 water indicate human influence 

 

 MCL

Figure 14. Percentage of nitrate concentrations in wells and 1993 

synoptic stream-sampling sites that exceeded the indicated 

concentrations. Nitrate was most often detected in a synoptic survey 

of surface water, but never at concentrations greater than 1.4 mg/L. 

The highest concentrations were in ground water from beneath 

agricultural fields.
16 Water Quality in the Hudson River Basin, New York and Adjacent States, 1992-95

WATER-QUALITY CONDITIONS IN A NATIONAL CONTEXT

Comparison of Stream Quality in the Hudson River Basin 

with Nationwide NAWQA Findings

Nutrient concentrations at most 

streams sampled were below the 

national median. Streams with the 

lowest concentrations were generally in forested areas; the stream with 

the highest concentrations drained a 

highly urbanized watershed.

Pesticide concentrations were below the 

national median in the two streams sampled that drain agricultural land. The aquatic life criteria for atrazine was exceeded at 

one site in July 1994. The stream with pesticide concentrations above the national 

median contained elevated concentrations 

of the insecticides diazinon and carbaryl. 

This watershed contains a large percentage 

of lawn and turf areas to which diazinon 

and carbaryl are commonly applied.

Albany

Utica

Hudson River

New York City 

Mohawk River

Albany

Utica

Hudson River

New York City 

Mohawk River

Albany

Utica

Hudson River

Mohawk River

New York City 

NUTRIENTS in water

Concentrations of organochlorine 

compounds at most sites surveyed 

were above the national median, and 

most were among the highest 25 percent. Most of the elevated concentrations were due to very high 

concentrations of PCBs in stream-bottom sediments and (or) fish tissue. 

Some of the highest concentrations of 

PCBs in the Nation are in the Hudson 

River; concentrations of PCBs in 

some urban watersheds tributary to 

the Hudson River are also high. New 

York State sediment screening guidelines, are exceeded for PCBs in many 

streams, and for DDT residues in 

some streams draining urban areas.

ORGANOCHLORINE PESTICIDES and PCBs

in stream-bottom sediment and fish tissue

PESTICIDES in water

Seven major water-quality characteristics were evaluated for stream sites in each 

NAWQA Study Unit. Summary scores for each characteristic were computed for all 

sites that had adequate data. Scores for each site in the the Hudson River Basin were 

compared with scores for all sites sampled in the 20 NAWQA Study Units during 

1992–95. Results are summarized by percentiles; higher percentiles generally 

indicate poorer quality compared with other NAWQA sites. Water-quality 

conditions at each site also are compared to established criteria for protection of 

aquatic life. Applicable criteria are limited to nutrients and pesticides in water, and 

semivolatile organic compounds, organochlorine pesticides, and PCBs in sediment. 

(Methods used to compute rankings and evaluate aquatic-life criteria are described 

by Gilliom and others, in press.)

Greater than the 75th percentile

(among the highest 25 percent

of NAWQA stream sites)

Between the median and the 75th percentile

Between the 25th percentile and the median

Less than the 25th percentile

(among the lowest 25 percent

of NAWQA stream sites)

EXPLANATION

Ranking of stream quality relative to all 

NAWQA stream sites — Darker colored 

circles generally indicate poorer quality. 

Bold outline of circle indicates one or more 

aquatic life criteria were exceeded.
WATER-QUALITY CONDITIONS IN A NATIONAL CONTEXT

Comparison of Stream Quality in the Hudson River Basin

with Nationwide NAWQA Findings

U.S. Geological Survey Circular 1165 17

Fish communities at all six sites differed from those communities expected 

under minimally impaired conditions, and degradation of the communities 

at four of these six sites was above the national median. The most severely 

impaired fish communities were from two streams in densely populated 

watersheds and one stream in a mostly agricultural watershed. These sites 

were characterized by the absence or rarity of pollution-intolerant species, 

and most of these sites were numerically dominated by species that feed on 

a wide variety of foods. These communities could be responding to a combination of several distrubances including nonpoint-source nutrients and 

pesticides, destruction of forested buffer zones, point-source discharges of 

sewage and industrial waste, and (or) stream channelization.

CONCLUSIONS

Compared to other NAWQA 

Study Units, some streams, particularly those draining urban areas and 

large watersheds, had elevated concentrations of trace elements and 

semivolatile organic compounds in 

stream-bottom sediment, and organochlorine pesticides and PCBs in 

stream-bottom sediment and fish tissue. Stream habitat and fish communities in urban and agricultural 

streams were also impaired relative 

to streams in other Study Units. Pesticide and nutrient concentrations 

were generally lower at sites sampled in the Hudson River Basin than 

those sites in other Study Units.

Albany

Utica

Hudson River

Mohawk River

New York City 

Albany

Utica

Hudson River

Mohawk River

New York City 

Albany

Utica

Hudson River

Mohawk River

New York City 

Concentrations of trace elements in stream-bottom sediments from most sites in the 

Hudson River Basin were 

near or above the national 

median. Trace-element concentrations were particularly 

high in urbanized watersheds.

Concentrations of semivolatile 

organic compounds — including PAHs, phthalates and phenols — in stream-bottom 

sediment were above the National median for all sites in the 

Hudson River Basin. Two of 

the highest national concentrations of these compounds were 

in the two most urbanized sites 

sampled in the Hudson River 

Basin; concentrations of 1 phthalate and at least 5 PAHs exceeded the aquatic life criteria 

at these sites.

Albany

Utica

Hudson River

Mohawk River

New York City 

Degradation of fish habitats along urban 

streams in the Hudson River Basin is greater 

than the national median, largely as a result of 

channel straightening and other forms of bank 

alteration. Stable habitats such as pools were 

absent or poorly developed along many 

reaches, and large fluctuations in streamflow 

were common. Stream habitats in two agricultural watersheds were degraded by bank 

erosion and removal of tree canopy; degradation at these sites also slightly exceeded the 

national median. Stream habitat in a residential watershed, with a wide forested buffer, 

and in a mostly forested watershed was relatively undisturbed, and degradation was below the national median.

SEMIVOLATILE ORGANIC COMPOUNDS

in stream-bottom sediment

FISH-COMMUNITY DEGRADATION

STREAM-HABITAT DEGRADATION

TRACE ELEMENTS in streambottom sediment
18 Water Quality in the Hudson River Basin, New York and Adjacent States, 1992-95

WATER-QUALITY CONDITIONS IN A NATIONAL CONTEXT

Comparison of Ground-Water Findings in the Hudson River Basin

with Nationwide NAWQA Findings

Utica

Poughkeepsie

Albany

New York City

Radon levels in the Hudson 

River Basin were generally 

lower than the national median, 

although radon levels in water 

from a few individual domestic-use wells were above the 

national median.

New York City

Utica

Poughkeepsie

Albany

Nitrate concentrations in the 

Hudson River Basin were below 

the national median for the shallow urban and domestic well 

samples but above the national 

median for the shallow agricultural well samples. Concentrations and exceedances of 

drinking-water criteria were 

highest in agricultural areas, although these waters are not widely used for drinking-water 

supply.

RADON

NITRATE

EXPLANATION

Drinking-water aquifers

Domestic well survey

Shallow ground-water areas

Agricultural area

Urban area

Five major water-quality characteristics were evaluated for ground-water studies in each 

NAWQA Study Unit. Ground-water resources were divided into two categories:

(1) drinking-water aquifers, and (2) shallow ground water underlying agricultural or 

urban areas. Summary scores were computed for each characteristic for all aquifers and 

shallow ground-water areas that had adequate data. Scores for each aquifer and shallow 

ground-water area in the Hudson River Basin were compared with scores for all aquifers 

and shallow ground-water areas sampled in the 20 NAWQA Study Units during 1992–

95. Results are summarized by percentiles; higher percentiles generally indicate poorer 

quality compared with other NAWQA ground-water studies. Water-quality conditions 

for each drinking-water aquifer also are compared to established drinking-water 

standards and criteria for protection of human health. (Methods used to compute 

rankings and evaluate standards and criteria are described by Gilliom and others, in 

press.)

Ranking of ground-water quality relative 

to all NAWQA ground-water studies — 

Darker colored circles generally indicate 

poorer quality. Bold outline of circle 

indicates one or more standards or criteria 

were exceeded

Greater than the 75th percentile

(among the highest 25 percent

of NAWQA ground-water studies)

Between the median and the 75th percentile

Between the 25th percentile and the median

Less than the 25th percentile

(among the lowest 25 percent

of NAWQA ground-water studies)

NOTE: The area mapped as part of the domesticwell survey reflects the spatial extent of two physiographic regions in which the survey was conducted, 

rather than the location and extent of aquifers sampled in this survey. The areas mapped as shallow 

ground-water areas correspond to the location and 

extent of aquifers underlying the agricultural and 

urban areas studied.
U.S. Geological Survey Circular 1165 19

WATER-QUALITY CONDITIONS IN A NATIONAL CONTEXT

Comparison of Ground-Water Findings in the Hudson River Basin

with Nationwide NAWQA Findings

Utica

Poughkeepsie

Albany

New York City

Utica

Poughkeepsie

Albany

New York City

Pesticides were detected most frequently in agricultural areas, and the frequency exceeded the national median. Concentrations in these samples were 

generally low, however, and no concentrations exceeded any available waterquality standard. Pesticide detection for the domestic-well and shallow-urban 

well samples was below the national median, and none of the concentrations 

in these samples exceeded any available water-quality standard.

Shallow urban wells had the most 

frequent detection of volatile organic 

compounds (VOCs). About one-third 

of those wells contained one or more 

VOCs; this detection rate is high 

relative to the national median. No 

VOC concentrations exceeded any 

water-quality standard, however, and 

the concentrations were low. Fewer 

than 7 percent of the domestic wells 

contained VOCs — a detection 

frequency lower than the national 

median.

CONCLUSIONS

Compared to other NAWQA Study 

Units, ground-water quality in the Hudson River Basin is similar to the median 

for comparable areas sampled nationally. 

Pesticides were most frequently 

detected in agricultural areas, and the 

rate of detection exceeded the national 

median. No concentrations exceeded 

drinking-water standards; however, 

drinking-water standards do not exist for 

some pesticides detected. VOC detection frequency exceeded the national 

median among urban wells sampled, but 

the concentrations detected in these 

wells were generally low. Nitrate and dissolved-solids concentrations in some 

wells in each of the three networks sampled exceeded drinking-water standards. 

Radon concentrations were among the 

lowest 25 percent nationally. 

Dissolved-solids concentrations in the shallow urban wells were 

above the national median, and dissolved-solids concentrations at 

34 percent of the urban wells exceeded the USEPA drinking-water 

standard. Dissolved-solids concentrations in samples from the agricultural and domestic wells also were above the national median, 

but fewer than 20 percent of these values exceeded the USEPA 

drinking-water standard.

DISSOLVED SOLIDS

Utica

Poughkeepsie

Albany

New York City

PESTICIDES

VOLATILE ORGANIC COMPOUNDS 
20 Water Q ality in the H dson River Basin New York and Adjacent States 1992-95

STUDY DESIGN AND DATA COLLECTION

One of the principal 

ways by which 

NAWQA attempts to 

describe water-quality 

conditions is through 

multiple lines of 

evidence (Hirsch and 

others, 1988). Site 

selection in the Hudson 

River Basin emphasized 

overlap of study 

components, particularly 

those related to stream 

chemistry and ecology. 

Overlap between 

“stream-chemistry” and 

“ecology” sites is 

summarized in the table 

below and depicted 

geographically in 

relation to land use in 

the figure at right.

In addition to the 

overlapping of sampling 

components, the 

distribution of sites 

throughout the basin and 

among the land-use 

categories was given 

considerable weight in 

site selection. The sites selected for one-time (synoptic) as 

well as long-term (Fixed Site) sampling were chosen to 

provide broad representation of streams and rivers draining 

forested, agricultural, urban/residential, and mixed land-use 

watersheds. Because water quality in forested watersheds 

(areas dominated by green in the figure above) typically 

shows little effect of human activities, only a few sites were 

sampled in such watersheds. In contrast, the variability of 

water quality is considerably greater among streams draining 

urban/residential and agricultural land; therefore, the number 

of sites needed to characterize water quality in these areas is 

high.

Two types of ground-water surveys were done; one was 

designed to reflect the effects of land use, the other to 

address the quality of drinking water from domestic wells. 

The two land-use surveys were designed to address the 

quality of shallow ground water beneath agricultural and 

urban/residential areas, which was poorly documented in 

upstate New York prior to these surveys.

Table 5. Number and type of stream-chemistry sites used in each stream-ecology-site category for the Hudson River Basin Study Unit

[Values indicate number of sites where both stream chemistry and ecological data were collected]

Type of stream-chemistry site

Ecology-site category

Fish community

survey (18 sites)

Algae and macroinvertebrate survey

(38 sites)

Ecological assessment (8 sites)Contaminants in fish 

tissue (26 sites)

Fixed Sites (14 sites) 8 9 8 11

Synoptic sites (46 sites) 18 38 8 18

Stream-bottom sediments (51 sites) 18 30 8 14

Click here to download the data collection network and land use maps (PDF, 2MB)
U.S. Geological Survey Circular 1165 21

STUDY DESIGN AND DATA COLLECTION

Study 

component Type of data collected and purpose Sites sampled

Number of 

sites

Sampling

frequency and 

period

Stream Chemistry

Fixed Sites Continuous streamflow and sampling for major ions, 

organic carbon, suspended sediment, and nutrients. 

 To document concentrations and loads.

Streams and rivers draining agricultural, urban, forested, and large 

(mixed-land-use) watersheds. 

14 Monthly plus storms, 

1993-95.

Intensive Fixed Sites Commonly used pesticides, including triazine 

herbicides.

To determine peak concentrations. 

Subset of fixed sites within Mohawk 

River Basin, including an urban 

site, an agricultural site, and a site 

at the Mohawk River mouth.

3 Monthly to weekly, 

1994-95. 

Synoptic sites Major ions, organic carbon, suspended sediment, 

nutrients, pesticides, and bacteria.

To show regional variability in water quality. 

Fixed sites and additional sites representative of major patterns of land 

use throughout the Hudson River 

Basin.

46 Early spring 1993, late 

summer 1993, late 

spring 1994.

Stream-bottom 

sediments

Trace elements, organochlorine and semivolatile 

organic compounds in stream-bottom sediment. 

To indicate regional variability in the chemical quality 

of stream-bottom sediment. 

Depositional zones of most Fixed and 

synoptic sites. 

51 Once during 1992-94.

Stream Ecology

Contaminants in fish 

tissue

Trace metals in fish livers and organochlorine

compounds in whole fish.

To describe spatial distribution of contaminants.

 A subset of stream sites sampled for 

stream-bottom sediments and 

synoptic site sampling.

26 Once or twice in 1992 

and (or) 1994.

Intensive ecological 

assessments

Composition and relative abundance of fishes; streamhabitat characterization.

To describe annual and within-stream variation; provide 

data for long-term monitoring.

Subset of Fixed Sites. 8 July-Sept. 1993-95 

(7 sites), and 1993-

94 (1 site); two additional sections sampled at each of 3 

sites in 1994.

Ecological synoptic 

survey — algae and 

macroinvertebrates

Species composition and abundance from macroinvertebrate and algal samples; habitat characterization. 

To describe spatial variation in biological communities 

and water and habitat quality.

Subset of synoptic sites. 38 Once during July -

August 1993.

Ecological synoptic 

survey — fish

Composition and relative abundance of fishes; streamhabitat characterization.

To describe spatial patterns in biological communities 

and water and habitat quality.

Subset of synoptic sites. 10 Once during August 

1995.

Ground-Water Chemistry

Survey of domestic 

wells 

Major ions, nutrients, commonly used pesticides, volatile organic compounds (VOCs), and radionuclides.

To document chemical quality of domestic water 

supplies. 

Domestic water wells throughout 

Hudson River Basin. Well depth 

ranged from 7 to more than 100 

feet below land surface.

49 Once in 1994.

Near-surface groundwater under 

agricultural fields 

Major ions, nutrients, commonly used pesticides, 

VOCs, and radionuclides. Wells were in or next to 

row-crop fields, pastures, or barns.

To characterize ground-water quality in agricultural 

areas. 

Shallow monitoring wells finished in 

Mohawk River Basin glacial and 

post-glacial deposits, generally 50 

feet deep or less. 

18 Once in 1994.

Near-surface groundwater under urban 

areas

Major ions, nutrients, commonly used pesticides, 

VOCs, radionuclides, and trace metals. Wells were in 

or next to lawns and schoolyards in residential areas.

To characterize ground-water quality in residential 

areas. 

Shallow monitoring wells finished in 

Mohawk River Basin glacial and 

post-glacial deposits, generally 50 

feet deep or less. 

26 Once in 1994.

Variation along 

ground-water flow 

paths

Major ions, nutrients, commonly used pesticides.

To characterize the fate and transport of chemicals 

along ground-water flow paths.

Shallow and deep monitoring wells, 

tile drains, and drainage ditches 

located on a corn-soybean farm.

32 Most sites at least 

twice, in 1993, 1994, 

or 1995.

Special Stream Studies

Nutrient processes Nutrients, dissolved oxygen, temperature, and algae 

species composition, abundance, and biomass.

To determine processes affecting nutrients.

Mainstem sites, agricultural drains, 

and small tributaries within Canajoharie Creek watershed. 

14 Once in spring 1995.

Base-flow pesticide 

study.

Commonly used pesticides and major ions.

To identify characteristics of source areas of pesticides 

to Canajoharie Creek.

Mainstem sites, agricultural drains, 

tile-drain outflows, and small tributaries within Canajoharie Creek 

watershed.

14 Once in spring 1995.
SUMMARY OF COMPOUND DETECTIONS AND CONCENTRATIONS

22 Water Quality in the Hudson River Basin, New York and Adjacent States, 1992-95

Herbicide

(Trade or common

name)

Rate

of

detection b

Concentration, in μg/L

0.001 0.01 0.1 1 10 100 1,000

The following tables summarize data collected for NAWQA studies from 1992-95 by showing results for the Hudson River

Basin Study Unit compared to the NAWQA national range for each compound detected. The data were collected at a wide variety of

places and times. In order to represent the wide concentration ranges observed among Study Units, logarithmic scales are used to

emphasize the general magnitude of concentrations (such as 10, 100, or 1,000), rather than the precise number. The complete dataset

used to construct these tables is available upon request.

Concentrations of herbicides, insecticides, volatile organic compounds, and nutrients detected in ground and surface waters of the

Hudson River Basin Study Unit. [mg/L, milligrams per liter; μg/L, micrograms per liter; pCi/L, picocuries per liter; %, percent; <, less than;

- -, not measured; trade names may vary]

EXPLANATION

Range of surface-water detections in all 20 Study Units

Detection in the Hudson River Basin Study Unit

Range of ground-water detections in all 20 Study Units

Drinking water standard or guideline a

Freshwater-chronic criterion for the protection of aquatic life a

Herbicide

(Trade or common

name)

Rate

of

detection b

Concentration, in μg/L

0.001 0.01 0.1 1 10 100 1,000

Prometon 

(Gesagram)

13%

4%

Pronamide 

(Kerb, propyzamid)

<1%

0%

Propanil

(Stampede, Surcopur)

<1%

0%

Simazine

(Aquazine, Princep) 

8%

<1%

Tebuthiuron 

(Spike, Perflan)

1%

1%

Terbacilc 1%

0%

Insecticide

(Trade or common

name)

Rate

of

detection b

Concentration, in μg/L

Carbarylc

(Sevin, Savit)

12%

0%

Carbofuranc

(Furadan)

<1%

0%

Chlorpyrifos 

(Dursban, Lorsban)

1%

0%

p,p'-DDE 

(p,p'-DDT metabolite)

0%

<1%

Diazinon 16%

2%

alpha-HCH 

(alpha-lindane)

<1%

0%

Malathion 

(malathon, Cythion)

<1%

1%

0.001 0.01 0.1 1 10 100 1,000

Alachlor

(Lasso)

4%

0%

2,6-Diethylaniline

(Alachlor degradate)

<1%

0%

Atrazine

(AAtrex, Gesaprim)

75%

19%

Deethylatrazinec

(Atrazine degradate)

43%

16%

Cyanazine 

(Bladex, Fortrol)

29%

11%

2,4-D

(2,4-PA)

1%

0%

DCPA

(Dacthal)

<1%

0%

Diuron 

(Karmex, Direx)

1%

1%

EPTC

(Eptam)

<1%

1%

Metolachlor

(Dual, Pennant)

55%

17%

Metribuzin

(Lexone, Sencor)

3%

3%

Molinate

(Ordram)

<1%

1%

Napropamide

(Devrinol)

<1%

0%

Neburon

(Neburex, Noruben)

1%

0%

Pebulate

(Tillam)

<1%

0%

Pendimethalin

(Prowl, Stomp)

7%

6%

(Sinbar)
SUMMARY OF COMPOUND DETECTIONS AND CONCENTRATIONS

U.S. Geological Survey Circular 1165 23

1,1,1-Trichloroethane --

1%

1,1-Dichloroethane --

1%

total Trihalomethanes --

11%

Volatile organic

compound

(Trade or common

name)

Rate

of

detection b

Concentration, in μg/L

Methyl tert-butyld

ether (MTBE)

--

6%

0.01 0.1 1 10 100 1,000 10,000 100,000

Dissolved ammonia 90%

81%

Dissolved ammonia

plus organic nitrogen

as nitrogen

57%

27%

Dissolved phosphorus as phosphorus

58%

29%

Dissolved nitrite plus

nitrate

92%

61%

Other Rate

of

detection b

Concentration, in pCi/L

Radon 222 --

94%

1 10 100 1,000 10,000 100,000

Nutrient

(Trade or common

name)

Rate

of

detection b

Concentration, in mg/L

0.01 0.1 1 10 100 1,000 10,000 100,000

Volatile organic

compound

(Trade or common

name)

Rate

of

detection b

Concentration, in μg/L

0.01 0.1 1 10 100 1,000
SUMMARY OF COMPOUND DETECTIONS AND CONCENTRATIONS

24 Water Quality in the Hudson River Basin, New York and Adjacent States, 1992-95

Herbicides, insecticides, volatile organic compounds, and nutrients not detected in ground and surface waters of the Hudson River Basin

Study Unit.

Herbicides

2,4,5-T

2,4,5-TP (Silvex, Fenoprop)

2,4-DB (Butyrac, Butoxone, Embutox Plus, Embutone)

Acetochlor (Harness Plus,

Surpass)

Acifluorfen (Blazer, Tackle

2S)

Benfluralin (Balan, Benefin,

Bonalan, Benefex)

Bentazon (Basagran, Bentazone, Bendioxide)

Bromacil (Hyvar X, Urox

B, Bromax)

Bromoxynil (Buctril, Brominal)

Butylate (Sutan +, Genate

Plus, Butilate)

Chloramben (Amiben,

Amilon-WP, Vegiben)

Clopyralid (Stinger, Lontrel, Reclaim, Transline)

Dacthal mono-acid (Dacthal

metabolite)

Dicamba (Banvel, Dianat,

Scotts Proturf)

Dichlorprop (2,4-DP, Seritox 50, Kildip, Lentemul)

Dinoseb (Dinosebe)

Ethalfluralin (Sonalan, Curbit)

Fenuron (Fenulon, Fenidim)

Fluometuron (Flo-Met,

Cotoran, Cottonex, Meturon)

Linuron (Lorox, Linex, Sarclex, Linurex, Afalon)

MCPA (Rhomene, Rhonox,

Chiptox)

MCPB (Thistrol)

Norflurazon (Evital, Predict, Solicam, Zorial)

Oryzalin (Surflan, Dirimal)

Picloram (Grazon, Tordon)

Propachlor (Ramrod, Satecid)

Propham (Tuberite)

Thiobencarb (Bolero, Saturn, Benthiocarb, Abolish)

Triallate (Far-Go, Avadex

BW, Tri-allate)

Triclopyr (Garlon, Grandstand, Redeem, Remedy)

Trifluralin (Treflan, Gowan,

Tri-4, Trific, Trilin)

Insecticides

3-Hydroxycarbofuran (Carbofuran metabolite)

Aldicarb sulfone (Standak,

aldoxycarb, aldicarb metabolite)

Aldicarb sulfoxide (Aldicarb metabolite)

Aldicarb (Temik, Ambush,

Pounce)

Azinphos-methyl (Guthion,

Gusathion M)

Dieldrin (Panoram D-31,

Octalox, Compound 497,

Aldrin epoxide)

Disulfoton (Disyston, DiSyston, Frumin AL,

Solvirex, Ethylthiodemeton)

Ethoprop (Mocap, Ethoprophos)

Fonofos (Dyfonate, Capfos,

Cudgel, Tycap)

Methiocarb (Slug-Geta,

Grandslam, Mesurol)

Methomyl (Lanox, Lannate, Acinate)

Methyl parathion (PenncapM, Folidol-M, Metacide,

Bladan M)

Oxamyl (Vydate L, Pratt)

Parathion (Roethyl-P, Alkron, Panthion, Phoskil)

Phorate (Thimet, Granutox,

Geomet, Rampart)

Propargite (Comite, Omite,

Ornamite)

1,2-Dichloropropane (Propylene dichloride)

1,3,5-Trimethylbenzene

(Mesitylene)

1,3-Dichlorobenzene (mDichlorobenzene)

1,3-Dichloropropane (Trimethylene dichloride)

1,4-Dichlorobenzene (pDichlorobenzene, 1,4-

DCB)

1-Chloro-2-methylbenzene (o-Chlorotoluene)

1-Chloro-4-methylbenzene (p-Chlorotoluene)

2,2-Dichloropropane

Benzene

Bromobenzene (Phenyl

bromide)

Bromochloromethane

(Methylene chlorobromide)

Bromomethane (Methyl

bromide)

Chlorobenzene

(Monochlorobenzene)

Chloroethane (Ethyl chloride)

Chloroethene (Vinyl chloride)

Chloromethane (Methyl

chloride)

Dibromomethane (Methylene dibromide)

Dichlorodifluoromethane

(CFC 12, Freon 12)

Dichloromethane (Methylene chloride)

Dimethylbenzenes

(Xylenes (total))

Ethenylbenzene (Styrene)

Ethylbenzene (Phenylethane)

Hexachlorobutadiene

Isopropylbenzene

(Cumene)

Methylbenzene (Toluene)

Naphthalene

Propoxur (Baygon, Blattanex, Unden, Proprotox)

Terbufos (Contraven,

Counter, Pilarfox)

cis-Permethrin (Ambush,

Astro, Pounce, Pramex,

Pertox, Ambushfog, Kafil,

Perthrine, Picket, Picket

G, Dragnet, Talcord, Outflank, Stockade, Eksmin,

Coopex, Peregin, Stomoxin, Stomoxin P, Qamlin, Corsair, Tornade)

gamma-HCH (Lindane,

gamma-BHC, Gammexane, Gexane, Soprocide,

gamma-hexachlorocyclohexane, gamma-benzene

hexachloride)

Volatile organic

compounds

1,1,1,2-Tetrachloroethane

(1,1,1,2-TeCA)

1,1,2,2-Tetrachloroethane

1,1,2-Trichloro-1,2,2-trifluoroethane (Freon 113,

CFC 113)

1,1,2-Trichloroethane

(Vinyl trichloride)

1,1-Dichloroethene

(Vinylidene chloride)

1,1-Dichloropropene

1,2,3-Trichlorobenzene

(1,2,3-TCB)

1,2,3-Trichloropropane

(Allyl trichloride)

1,2,4-Trichlorobenzene

1,2,4-Trimethylbenzene

(Pseudocumene)

1,2-Dibromo-3-chloropropane (DBCP, Nemagon)

1,2-Dibromoethane (EDB,

Ethylene dibromide)

1,2-Dichlorobenzene (oDichlorobenzene, 1,2-

DCB)

1,2-Dichloroethane (Ethylene dichloride)

Tetrachloroethene (Perchloroethene)

Tetrachloromethane (Carbon tetrachloride)

Trichloroethene (TCE)

Trichlorofluoromethane

(CFC 11, Freon 11)

cis-1,2-Dichloroethene

((Z)-1,2-Dichloroethene)

cis-1,3-Dichloropropene

((Z)-1,3-Dichloropropene)

n-Butylbenzene (1-Phenylbutane)

n-Propylbenzene (Isocumene)

p-Isopropyltoluene (pCymene)

sec-Butylbenzene

tert-Butylbenzene

trans-1,2-Dichloroethene

((E)-1,2-Dichlorothene)

trans-1,3-Dichloropropene

((E)-1,3-Dichloropropene)

Nutrients

No non-detects
SUMMARY OF COMPOUND DETECTIONS AND CONCENTRATIONS

U.S. Geological Survey Circular 1165 25

1,2-Dichlorobenzene --

3%

1,2-Dimethylnaphthalene

--

21%

1,3-Dichlorobenzene --

3%

1,4-Dichlorobenzene --

12%

1,6-Dimethylnaphthalene

--

58%

1-Methyl-9H-fluorene --

45%

1-Methylphenanthrene

--

85%

1-Methylpyrene --

76%

2,2-Biquinoline --

18%

2,3,6-Trimethylnaphthalene

--

45%

2,6-Dimethylnaphthalene

--

97%

2,6-Dinitrotoluene --

3%

2-Ethylnaphthalene --

36%

2-Methylanthracene --

67%

4,5-Methylenephenanthrene

--

79%

9H-Carbazole --

70%

9H-Fluorene --

70%

Concentrations of semivolatile organic compounds, organochlorine compounds, and trace elements detected in fish tissue and streambottom sediment of the Hudson River Basin Study Unit [μg/g, micrograms per gram; μg/kg, micrograms per kilogram; %, percent;

<, less than; --, not measured; trade names may vary]

EXPLANATION

Range of detections in fish tissue in all 20 Study Units

Detection in stream-bottom sediment or fish tissue in the Hudson River Basin Study Unit

Range of detections in stream-bottom sediment in all 20 Study Units

Guideline for the protection of aquatic life e

Semivolatile

organic compound

Rate of

detection b

Concentration, in μg/kg

0.1 10 100 1,000 10,000 100,000 1

Semivolatile

organic compound

Rate of

detection b

Concentration, in μg/kg

0.1 10 100 1,000 10,000 100,000 1

Acenaphthene --

67%

Acenaphthylene --

91%

Acridine --

42%

Anthracene --

97%

Anthraquinone --

82%

Benz[ a ]anthracene --

100%

Benzo[ a ]pyrene --

97%

Benzo[ b ]fluoranthene

--

100%

Benzo[ c ]cinnoline --

6%

Benzo[ ghi ]perylene --

67%

Benzo[ k ]fluoranthene

--

100%

Butylbenzylphthalate --

91%

C8-Alkylphenol --

12%

Chrysene --

97%

Di- n -butylphthalate --

97%

Di- n -octylphthalate --

36%

Dibenz[ a,h ]

anthracene

--

55%
SUMMARY OF COMPOUND DETECTIONS AND CONCENTRATIONS

26 Water Quality in the Hudson River Basin, New York and Adjacent States, 1992-95

Dibenzothiophene --

70%

Diethylphthalate --

48%

Dimethylphthalate --

18%

Fluoranthene --

100%

Indeno[1,2,3- cd ]

pyrene

--

88%

Isoquinoline --

21%

Naphthalene --

58%

N-Nitrosodiphenylamine

--

18%

Phenanthrene --

97%

Phenanthridine --

21%

Phenol --

97%

Pyrene --

97%

Quinoline --

15%

bis(2-Ethylhexyl)

phthalate

--

97%

p-Cresol --

91%

total-Chlordane 41%

29%

p,p'-DDE 89%

62%

total-DDT 96%

62%

Dieldrin 

(Panoram D-31)

30%

13%

Endosulfan I 

(alpha-endosulfan)

--

2%

gamma-HCH

(lindane) 

4%

0%

Heptachlor epoxide

(heptachlor degredate)

2%

0%

PCB, total 76%

33%

Pentachloroanisole 2%

0%

Trace element Rate

of

detection b

Concentration, in μg/g

Arsenic 48%

100%

Cadmium 76%

100%

Chromium 88%

100%

Copper 100%

100%

Lead 24%

100%

Mercury 84%

98%

Nickel 88%

100%

Selenium 100%

100%

Zinc 100%

100%

0.01 0.1 1 10 100 1,000 10,000

Semivolatile

organic compound

Rate of

detection b

Concentration, in μg/kg

0.1 10 100 1,000 10,000 100,000 1

Organochlorine

compound

(Trade name)

Rate

of

detection b

Concentration, in μg/kg

0.01 0.1 1 10 100 1,000 10,000 100,000
SUMMARY OF COMPOUND DETECTIONS AND CONCENTRATIONS

U.S. Geological Survey Circular 1165 27

Semivolatile organic compounds, organochlorine compounds, and trace elements not detected in fish tissue and stream-bottom 

sediment of the Hudson River Basin Study Unit.

Semivolatile

organic

compounds

1,2,4-Trichlorobenzene

2,4-Dinitrotoluene

2-Chloronaphthalene

2-Chlorophenol

3,5-Dimethylphenol

4-Bromophenylphenylether

4-Chloro-3-methylphenol

4-Chlorophenylphenylether

Azobenzene

Isophorone

N-Nitrosodi-n-propylamine

Nitrobenzene

Pentachloronitrobenzene

bis (2-Chloroethoxy)methane

Organochlorine

compounds

Aldrin (HHDN, Octalene)

Chloroneb (chloronebe,

Demosan, Soil Fungicide

1823)

DCPA (Dacthal, chlorthaldimethyl)

Endrin (Endrine)

Heptachlor (Heptachlore,

Velsicol 104)

Hexachlorobenzene (HCB)

Isodrin (Isodrine, Compound 711)

Mirex (Dechlorane)

Toxaphene (Camphechlor,

Hercules 3956)

alpha-HCH (alpha-BHC,

alpha-lindane, alphahexachlorocyclohexane,

alpha-benzene hexachloride)

beta-HCH (beta-BHC,

beta-hexachlorocyclohexane, alpha-benzene

hexachloride)

cis-Permethrin (Ambush,

Astro, Pounce, Pramex,

Pertox, Ambushfog, Kafil,

Perthrine, Picket, Picket

G, Dragnet, Talcord, Outflank, Stockade, Eksmin,

Coopex, Peregin, Stomoxin, Stomoxin P, Qamlin, Corsair, Tornade)

delta-HCH (delta-BHC,

delta-hexachlorocyclohexane, delta-benzene

hexachloride)

o,p'-Methoxychlor

p,p'-Methoxychlor (Marlate, methoxychlore)

trans-Permethrin

(Ambush, Astro, Pounce,

Pramex, Pertox, Ambushfog, Kafil, Perthrine,

Picket, Picket G, Dragnet,

Talcord, Outflank, Stockade, Eksmin, Coopex, Peregin, Stomoxin, Stomoxin

P, Qamlin, Corsair, Tornade)

1,2,4-Trichlorobenzene

2,4-Dinitrotoluene

2-Chloronaphthalene

2-Chlorophenol

3,5-Dimethylphenol

4-Bromophenyl-phenylether

4-Chloro-3-methylphenol

4-Chlorophenylphenylether

Azobenzene

Isophorone

N-Nitrosodi-n-propylamine

Nitrobenzene

Pentachloronitrobenzene

bis (2-Chloroethoxy)methane

Trace elements

No non-detects

a

 Selected water-quality standards and guidelines (Gilliom and others, in press).

b Rates of detection are based on the number of analyses and detections in the Study Unit, not on national data. Rates of detection for herbicides and

insecticides were computed by only counting detections equal to or greater than 0.01 μg/L in order to facilitate equal comparisons among compounds, which had widely varying detection limits. For herbicides and insecticides, a detection rate of "<1%" means that all detections are less than

0.01 μg/L, or the detection rate rounds to less than one percent. For other compound groups, all detections were counted, and minimum detection 

limits for most compounds were similar to the lower end of the national ranges shown. Method detection limits for all compounds in these tables

are summarized in Gilliom and others (in press).

c

 Detections of these compounds are reliable, but concentrations are determined with greater uncertainty than for the other compounds and are reported

as estimated values (Zaugg and others, 1995).

d The guideline for methyl tert-butyl ether is between 20 and 40 μg/L; if the tentative cancer classification C is accepted, the lifetime health advisory 

will be 20 μg/L (Gilliom and others, in press).

e

 Selected sediment-quality guidelines (Gilliom and others, in press).
28 Water Quality in the Hudson River Basin, New York and Adjacent States, 1992-95

REFERENCES

Armstrong, R.W. and Sloan, R.J., 1987, PCB patterns in 

Hudson River fish: resident freshwater species, in C.L. 

Smith (ed.), Fisheries Research in the Hudson River – 

Proceedings of the Hudson River Environmental Society Conference: Albany, N.Y., State University of New 

York Press, p. 304-324.

Bode, R.W., Novak, M.A., and Abele, L.E., 1996, Quality 

assurance workplan for biological stream monitoring in 

New York State: New York State Department of Environmental Conservation, 89 p.

Butch, G.K., Dalton, F.N., Lent, H.G., and Murray, P.M., 

1996, Water resources data – New York, water year 

1996: U.S. Geological Survey Water-Data Report NY96-1, 398 p.

Gilliom, R.J., Mueller, D.K., and Nowell, L.H., in press, 

Methods for comparing water-quality conditions among 

National Water-Quality Assessment Study Units, 1992-

95: U.S. Geological Survey Open-File Report 97-589.

Hirsch, R.M., Alley, W.M., and Wilber, W.G., 1988, A summary of the U.S. Geological Survey National WaterQuality Assessment Program: U.S. Geological Survey 

Open-File Report 88-95, 7 p.

Limburg, K.E., Moran, M.A., and McDowell, W.H., 1986, 

The Hudson River ecosystem: New York, SpringerVerlag, 344 p.

Madison, R.J. and Brunett, J.O., 1994, Overview of the 

occurrence of nitrate in ground water of the United 

States, in National water summary, 1984: U.S. Geological Survey Water-Supply Paper 2275, p. 93-105.

Neff, J.M., 1979, Polycyclic aromatic hydrocarbons in the 

aquatic environment — Sources, fates and biological 

effects: London [U.K.], Applied Science Publishers, 

262 p.

Newell, A.J., Johnson, D.W., and Allen, L.K., 1987, Niagara 

River biota contamination project—fish flesh criteria 

for piscivorous wildlife: New York State Department of 

Environmental Conservation, Division of Fish and 

Wildlife, Bureau of Environmental Protection Technical 

Report 87-3, 182 p.

New York State Department of Environmental Conservation, 

1994, Technical guidance for screening contaminated 

sediments: Albany, N.Y., Division of Fish and Wildlife, 

Division of Marine Resources, 36 p.

New York State Department of Health, 1997, Chemicals in 

sportfish and game – 1997-1998 health advisories: 

Albany, N.Y., New York State Department of Health, 

Division of Environmental Health Assessment, 15 p.

Phillips, P.J., and Hanchar, D.W., 1996, Water-quality assessment of the Hudson River Basin in New York and adjacent States — Analysis of available nutrient, pesticide, 

volatile organic compound, and suspended-sediment 

data, 1970-90: U.S. Geological Survey WaterResources Investigations Report 96-4065, 76 p.

Phillips, P.J., Riva-Murray, Karen, Hollister, H.M., and Flanary, E.A., 1997, Distribution of DDT, chlordane, and 

total PCB's in bed sediments in the Hudson River 

Basin: New York State and the Environment, v. 3, no. 1, 

p. 26-47. 

Murray, K.R., Phillips, P.J., and Rouse, G.L., 1996, Relations among benthic invertebrate communities, environmental conditions, and land use in streams of the 

Hudson River Basin, New York, 1993. American Geophysical Union 1996 Spring Meeting Supplement, 

v. 77, no. 17, p. S117.

Rod, S.R., 1989, Estimation of historical pollution trends 

using mass balance principles — Selected metals and 

pesticides in the Hudson-Raritan Basin, 1880-1980: 

Pittsburgh, Carnegie-Mellon University, unpublished 

dissertation, 212 p.

Wall, G.R., and Phillips, P.J., 1996a, Pesticides in surface 

waters of the Hudson River Basin — Mohawk River 

subbasin: U.S. Geological Survey Fact Sheet 237-96, 

4 p.

_____ 1996b, Pesticides in surface waters of the Hudson 

River Basin, New York and adjacent States: U.S. Geological Survey Fact Sheet 238-96, 4 p.

Zaugg, S.D., Sandstrom, M.W., Smith, S.G., and Fehlberg, 

K.M., 1995, Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory - Determination of pesticides in water by C-18 solid-phase 

extraction and capillary-column gas chromatography / 

mass spectrometry with selected-ion monitoring: U.S. 

Geological Survey Open-File Report 95-181, 49 p.
GLOSSARY 

U.S. Geological Survey Circular 1165 29

The terms in this glossary were compiled from 

numerous sources. Some definitions have been modified 

and may not be the only valid ones for these terms.

Aquifer - A water-bearing layer of soil, sand, gravel, or 

rock that will yield usable quantities of water to a well.

Atmospheric deposition - The transfer of substances from 

the air to the surface of the Earth, either in wet form (rain, 

fog, snow, dew, frost, hail) or in dry form (gases, aerosols, 

particles).

Background concentration - A concentration of a 

substance in a particular environment that is indicative of 

minimal influence by human (anthropogenic) sources.

Bank - The sloping ground that borders a stream and 

confines the water in the natural channel when the water 

level, or flow, is normal.

Base flow - Sustained, low flow in a stream; ground-water 

discharge is the source of base flow in most places.

Basin - See Drainage basin.

Benthic invertebrates - Insects, mollusks, crustaceans, 

worms, and other organisms without a backbone that live 

in, on, or near the bottom of lakes, streams, or oceans.

Bioaccumulation - The biological sequestering of a 

substance at a higher concentration than that at which it 

occurs in the surrounding environment or medium. Also, 

the process whereby a substance enters organisms through 

the gills, epithelial tissues, dietary, or other sources.

Biota - Living organisms.

Blue-baby syndrome - A condition that can be caused by 

ingestion of high amounts of nitrate resulting in the blood 

losing its ability to effectively carry oxygen. It is most 

common in young infants and certain elderly people.

Breakdown product - See Degradation compound.

Channelization - Modification of a stream, typically by 

straightening the channel, to provide more uniform flow; 

often done for flood control or for improved agricultural 

drainage or irrigation.

Chlordane - Octachloro-4,7-methanotetrahydroindane. An 

organochlorine insecticide no longer registered for use in 

the United States. Technical chlordane is a mixture in 

which the primary components are cis- and transchlordane, cis- and trans-nonachlor, and heptachlor.

Community - In ecology, the species that interact in a 

common area.

Concentration - The amount or mass of a substance 

present in a given volume or mass of sample. Usually 

expressed as micrograms per liter (water sample) or 

micrograms per kilogram (sediment or tissue sample).

Constituent - A chemical or biological substance in water, 

sediment, or biota that can be measured by an analytical 

method.

Contamination - Degradation of water quality compared to 

original or natural conditions due to human activity.

Criterion - A standard rule or test on which a judgment or 

decision can be based.

Cubic foot per second (ft3

/s, or cfs) - Rate of water 

discharge representing a volume of 1 cubic foot passing a 

given point during 1 second, equivalent to approximately 

7.48 gallons per second or 448.8 gallons per minute or 

0.02832 cubic meter per second.

Degradation compounds - Products resulting from 

transformation of an organic substance through chemical, 

photochemical, and (or) biochemical reactions.

Detection limit - The concentration below which a 

particular analytical method cannot determine, with a high 

degree of certainty, a concentration.

DDT - Dichloro-diphenyl-trichloroethane. An 

organochlorine insecticide no longer registered for use in 

the United States.

Discharge - Rate of fluid flow passing a given point at a 

given moment in time, expressed as volume per unit of time.

Dissolved solids - Amount of minerals, such as salt, that 

are dissolved in water; amount of dissolved solids is an 

indicator of salinity or hardness.

Drainage basin - The portion of the surface of the Earth 

that contributes water to a stream through overland runoff, 

including tributaries and impoundments. 

Drinking-water standard or guideline - A threshold 

concentration in a public drinking-water supply, designed 

to protect human health. As defined here, standards are 

U.S. Environmental Protection Agency regulations that 

specify the maximum contamination levels for public water 

systems required to protect the public welfare; guidelines 
GLOSSARY

30 Water Quality in the Hudson River Basin, New York and Adjacent States, 1992-95

have no regulatory status and are issued in an advisory 

capacity.

Drought - Commonly defined as being a time of less-thannormal or less-than-expected precipitation.

Ecosystem - The interacting populations of plants, animals, 

and microorganisms occupying an area, plus their physical 

environment.

Environmental setting - Land area characterized by a 

unique combination of natural and human-related factors, 

such as row-crop cultivation or glacial-till soils.

EPT richness index - An index based on the sum of the 

number of taxa in three insect orders, Ephemeroptera 

(mayflies), Plecoptera (stoneflies), and Trichoptera 

(caddisflies), that are composed primarily of species 

considered to be relatively intolerant to environmental 

alterations.

Erosion - The process whereby materials of the Earth's 

crust are loosened, dissolved, or worn away and 

simultaneously moved from one place to another. 

FDA action level - A regulatory level recommended by the 

U.S. Environmental Protection Agency for enforcement by 

the FDA when pesticide residues occur in food 

commodities for reasons other than the direct application of 

the pesticide. Action levels are set for inadvertent pesticide 

residues resulting from previous legal use or accidental 

contamination. Applies to edible portions of fish and 

shellfish in interstate commerce.

Fertilizer - Any of a large number of natural or synthetic 

materials, including manure and nitrogen, phosphorus, and 

potassium compounds, spread on or worked into soil to 

increase its fertility.

Fish community - See Community.

Fixed Sites - Sites on streams at which streamflow is 

measured and samples are collected for temperature, 

salinity, suspended sediment, major ions and metals, 

nutrients, and organic carbon to assess the broad-scale 

spatial and temporal character and transport of inorganic 

constituents of streamwater in relation to hydrologic 

conditions and environmental settings. 

Ground water - In general, any water that exists beneath 

the land surface, but more commonly applied to water in 

fully saturated soils and geologic formations.

Habitat - The part of the physical environment where 

plants and animals live.

Headwaters - The source and upper part of a stream.

Health advisory - Nonregulatory levels of contaminants in 

drinking water that may be used as guidance in the absence 

of regulatory limits. Advisories consist of estimates of 

concentrations that would result in no known or anticipated 

health effects (for carcinogens, a specified cancer risk) 

determined for a child or for an adult for various exposure 

periods.

Herbicide - A chemical or other agent applied for the 

purpose of killing undesirable plants. See also Pesticide.

Human health advisory - Guidance provided by U.S. 

Environmental Protection Agency, State agencies, or 

scientific organizations, in the absence of regulatory limits, 

to describe acceptable contaminant levels in drinking water 

or edible fish.

Hydrograph - Graph showing variation of water elevation, 

velocity, streamflow, or other property of water with 

respect to time.

Insecticide - A substance or mixture of substances intended 

to destroy or repel insects.

Intolerant organisms - Organisms that are not adaptable to 

human alterations to the environment and thus decline in 

numbers where human alterations occur. See also Tolerant 

species.

Invertebrate - An animal having no backbone or spinal 

column. See also Benthic invertebrate.

Kill - Dutch term for stream or creek.

Main stem - The principal course of a river or a stream.

Major ions - Constituents commonly present in 

concentrations exceeding 1.0 milligram per liter. Dissolved 

cations generally are calcium, magnesium, sodium, and 

potassium; the major anions are sulfate, chloride, fluoride, 

nitrate, and those contributing to alkalinity, most generally 

assumed to be bicarbonate and carbonate.

Maximum Contaminant Level (MCL) - Maximum 

permissible level of a contaminant in water that is delivered 

to any user of a public water system. MCLs are enforceable 

standards established by the U.S. Environmental Protection 

Agency.
GLOSSARY 

U.S. Geological Survey Circular 1165 31

Mean - The average of a set of observations, unless 

otherwise specified.

Median - The middle or central value in a distribution of 

data ranked in order of magnitude. The median is also 

known as the 50th percentile.

Method detection limit - The minimum concentration of a 

substance that can be accurately identified and measured 

with present laboratory technologies.

Micrograms per liter (μg/L) - A unit expressing the 

concentration of constituents in solution as weight 

(micrograms) of solute per unit volume (liter) of water; 

equivalent to one part per billion in most stream water and 

ground water. One thousand micrograms per liter equals 

1 mg/L.

Midge - A small fly in the family Chironomidae. The larval 

(juvenile) life stages are aquatic.

Milligrams per liter (mg/L) - A unit expressing the 

concentration of chemical constituents in solution as weight 

(milligrams) of solute per unit volume (liter) of water; 

equivalent to one part per million in most stream water and 

ground water. One thousand micrograms per liter equals 

1 mg/L.

Monitoring well - A well designed for measuring water 

levels and testing ground-water quality.

Nitrate - An ion consisting of nitrogen and oxygen (NO3

-

). 

Nitrate is a plant nutrient and is very mobile in soils.

Nonpoint source - A pollution source that cannot be 

defined as originating from discrete points such as pipe 

discharge. Areas of fertilizer and pesticide applications, 

atmospheric deposition, manure, and natural inputs from 

plants and trees are types of nonpoint source pollution.

Nutrient - Element or compound essential for animal and 

plant growth. Common nutrients in fertilizer include 

nitrogen, phosphorus, and potassium.

Organochlorine compound - Synthetic organic 

compounds containing chlorine. As generally used, term 

refers to compounds containing mostly or exclusively 

carbon, hydrogen, and chlorine. Examples include 

organochlorine insecticides, polychlorinated biphenyls, and 

some solvents containing chlorine.

Pesticide - A chemical applied to crops, rights of way, 

lawns, or residences to control weeds, insects, fungi, 

nematodes, rodents or other "pests."

Physiography - A description of the surface features of the 

Earth, with an emphasis on the origin of landforms.

Point source - A source at a discrete location such as a 

discharge pipe, drainage ditch, tunnel, well, concentrated 

livestock operation, or floating craft.

Polychlorinated biphenyls (PCBs) - A mixture of 

chlorinated derivatives of biphenyl, marketed under the 

trade name Aroclor with a number designating the chlorine 

content (such as Aroclor 1260). PCBs were used in 

transformers and capacitors for insulating purposes and in 

gas pipeline systems as a lubricant. Further sale for new use 

was banned by law in 1979.

Polycyclic aromatic hydrocarbon (PAH) - A class of 

organic compounds with a fused-ring aromatic structure. 

PAHs result from incomplete combustion of organic carbon 

(including wood), municipal solid waste, and fossil fuels, as 

well as from natural or anthropogenic introduction of 

uncombusted coal and oil. PAHs include benzo(a)pyrene, 

fluoranthene, and pyrene.

Pool - A small part of the stream reach with little velocity, 

commonly with water deeper than surrounding areas.

Radon - A naturally occurring, colorless, odorless, 

radioactive gas formed by the disintegration of the element 

radium; damaging to human lungs when inhaled.

Riffle - A shallow part of the stream where water flows 

swiftly over completely or partially submerged obstructions 

to produce surface agitation.

Runoff - Excess rainwater or snowmelt that is transported 

to streams by overland flow, tile drains, or ground water.

Sediment - Particles, derived from rocks or biological 

materials, that have been transported by a fluid or other 

natural process and are suspended or settled in water.

Semivolatile organic compound (SVOC) - Operationally 

defined as a group of synthetic organic compounds that are 

solvent-extractable and can be determined by gas 

chromatography/mass spectrometry. SVOCs include 

phenols, phthalates, and polycyclic aromatic hydrocarbons 

(PAHs).
GLOSSARY

32 Water Quality in the Hudson River Basin, New York and Adjacent States, 1992-95

Species - Populations of organisms that may interbreed and 

produce fertile offspring having similar structure, habits, 

and functions.

Stream-bottom sediment - The material that temporarily 

is stationary in the bottom of a stream or other watercourse.

Streamflow - A type of channel flow, applied to that part 

of surface runoff in a stream whether or not it is affected by 

diversion or regulation.

Study Unit - A major hydrologic system of the United 

States in which NAWQA studies are focused. Study Units 

are geographically defined by a combination of ground- and 

surface-water features and generally encompass more than 

4,000 square miles of land area.

Surface water - An open body of water, such as a lake, 

river, or stream.

Stream reach - A continuous part of a stream between two 

specified points.

Suspended sediment - Particles of rock, sand, soil, and 

organic detritus carried in suspension in the water column, 

in contrast to sediment that moves on or near the streambed.

Synoptic sites - Sites sampled during a short-term 

investigation of specific water-quality conditions during 

selected seasonal or hydrologic conditions to provide 

improved spatial resolution for critical water-quality 

conditions. 

Tolerant species - Those species that are adaptable to 

(tolerant of) human alterations to the environment and often 

increase in number when human alterations occur.

Trace element - An element found in only minor amounts 

(concentrations less than 1.0 milligram per liter) in water or 

sediment; includes arsenic, cadmium, chromium, copper, 

lead, mercury, nickel, and zinc.

Volatile organic compounds (VOCs) - Organic chemicals 

that have a high vapor pressure relative to their water 

solubility. VOCs include components of gasoline, fuel oils, 

and lubricants, as well as organic solvents, fumigants, some 

inert ingredients in pesticides, and some by-products of 

chlorine disinfection.

Water-quality criteria - Specific levels of water quality 

which, if reached, are expected to render a body of water 

unsuitable for its designated use. Commonly refers to waterquality criteria established by the U.S. Environmental 

Protection Agency. Water-quality criteria are based on 

specific levels of pollutants that would make the water 

harmful if used for drinking, swimming, farming, fish 

production, or industrial processes.

Watershed - See Drainage basin.
Wall, Riva-Murray, and Phillips • Water Quality in the Hudson River Basin

Albany

USGS Circular 1165 • 1998

New York 

Glens Falls

Utica

Amsterdam

Poughkeepsie

Newburgh

Hudson River

Lake Sacandaga 

Mohawk Rive r

Wallkill R.

National Water-Quality Assessment (NAWQA) Program

Hudson River Basin

NAWQA