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Missouri

Pacific Northwest

Rio Grande, Colorado,

and Great Basin and Great Basin 

South Atlantic-Gulf

and Tennessee

Great Lakes, Ohio, Upper Mississippi,

and Souris-Red-Rainy 

New England

& Mid-Atlantic 

Lower Mississippi,

Arkansas-White-Red,

and Texas-Gulf

#

California

Hawaii

Alaska

0 20 40 60 80 100

Toluene

Chloroform

Methyl tert-butyl ether

Trichloroethene

Perchloroethene

cis-1,2-Dichloroethene

m- and p-Xylene

Benzene

Chloromethane

1,2,4-Trimethylbenzene

o-Xylene

Dichloromethane

1,1,1-Trichloroethane

Carbon disulfide

Bromodichloromethane

VOC

Groups

Gasoline hydrocarbons

Gasoline oxygenates

Organic synthesis compounds

Solvents

Trihalomethanes (THMs)

Assessment level of 0.02 microgram 

 per liter

Fifteen most frequently detected VOCs at an assessment level 

of 0.02 microgram per liter

DETECTION FREQUENCY IN PERCENT

Concentrations of the 15 most frequently detected VOCs

0.001 0.01 0.1 1 10 100 1,000 10,000

1,2,4-Trimethylbenzene

Toluene

Chloroform

Methyl tert-butyl ether

Trichloroethene

Perchloroethene

cis-1,2-Dichloroethene

m- and p-Xylene

Benzene

Chloromethane

o-Xylene

Dichloromethane

1,1,1-Trichloroethane

Carbon disulfide

Bromodichloromethane

CONCENTRATION IN MICROGRAM PER LITER

April-September detected 

concentration

April-September median 

detected concentration 

October-March detected 

concentration

Long-term method 

detection limit 

Assessment level 

Maximum Contaminant 

Level

Drinking Water Advisory 

October-March median 

detected concentration 

EXPLANATION

Health Advisory Level 

Detected concentration 

less than the assessment 

level of 0.02 microgram 

per liter

0 20 40 60 80 100

BTEX gasoline hydrocarbons

Solvents

Trihalomethanes

Gasoline oxygenates

Other gasoline-related hydrocarbons

 Compounds used in organic synthesis

Fumigants

Refrigerants

PREDOMINANT USE/SOURCE

April-September (410 samples)

October-March (459 samples)

Detection frequency of VOC predominant use/source groups at an 

assessment level of 0.02 microgram per liter

DETECTION FREQUENCY, IN PERCENT

U.S. Department of the Interior

U.S. Geological Survey

Scientific Investigations Map 2937

Occurrence of Volatile Organic Compounds in Selected Urban Streams in the United States, 1995–2003

By David A. Bender, Curtis V. Price, and Joshua F. Valder

Study basics

The U.S. Geological Survey’s National Water-Quality Assessment (NAWQA) Program sampled 

37 urban streams throughout the United States for volatile organic compounds (VOCs) from 1995 

to 2003. These urban streams were selected to (1) characterize stream water quality from areas 

draining predominantly residential and commercial land uses and (2) determine which natural and 

human factors affect stream quality. Initial interpretation of the VOC data set is focused on determining which VOCs commonly are found, the range of concentrations, and the temporal distribution (Lopes and Price, 1997).

The 37 urban streams sampled had drainage areas that ranged from 23 to 13,000 square kilometers with a median of 71 square kilometers. The urban streams are located in eight major 

surface-water regions within the conterminous United States, Alaska, and Hawaii. The urban 

streams were sampled for VOCs monthly for about 1 year with some storm samples collected at 

selected sites (Lopes and Price, 1997). A total of 869 samples (410 samples in the warmer months 

and 459 samples in the cooler months) were collected and were analyzed for 85 individual VOCs. 

Data are available at http://infotrek.er.usgs.gov/pls/nawqa/nawqa.home

Site selection criteria

Urban stream located in a metropolitan statistical area with a population greater than 250,000.

Urban stream located in a NAWQA study unit.

Urban stream that has sustained flow and well defined drainages.

Urban stream that has minimal or no point-source discharges.

Urban stream that predominantly drains residential/commercial land use.

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One or more of 85 VOCs were detected in about 89 percent of samples in warmer months 

(April through September) and in about 95 percent of samples in cooler months (October 

through March).

A median of 5 VOCs were detected in warmer months, and 7 VOCs were detected 

in cooler months.

•

•

General findings

Fifty-six different VOCs were detected in urban streams at an assessment level of 

0.02 microgram per liter.

Thirteen VOCs had detection frequencies greater than 10 percent.

The 15 most frequently detected compounds are from five predominant use/source 

groups (gasoline hydrocarbons, trihalomethanes (disinfection by-products), gasoline oxygenates, solvents, and one organic synthesis compound).

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•

Concentrations were typically less than 1 microgram per liter.

No concentrations were larger than U.S. Environmental Protection Agency’s 

(USEPA) Maximum Contaminant Levels (U.S. Environmental Protection Agency, 

2004).

Methyl tert-butyl ether had some concentrations larger than the lower limit of 

USEPA’s Drinking Water Consumer Advisory of 20-40 micrograms per liter (U.S. 

Environmental Protection Agency, 2004).

•

•

•

National Map Showing Urban Stream Sites in Major Surface-Water Regions

Fumigants Gasoline 

hydrocarbon

Compounds used in 

organic synthesis Solvents

Bromomethane

trans-1,3-Dichloropropene

cis-1,3-Dichloropropene

1,2-Dibromoethane

1,2,3-Trichloropropane

tert-Butylbenzene 2-Propenenitrile

Hexachlorobutadiene

Methyl acrylate

Bromoethene

trans-1,4-Dichloro-2-butene

Ethyl methacrylate

1,1-Dichloropropene

2,2-Dichloropropane

1,3-Dichloropropane

Bromochloromethane

Iodomethane

3-Chloro-1-propene

Methyl acrylonitrile

Methyl methacrylate

1,2,3-Trichlorobenzene

Dibromomethane

1,1,1,2,2,2-Hexachloroethane

1,1,2-Trichloroethane

1,2,4-Trichlorobenzene

2-Hexanone

4-Chlorotoluene

1,1,1,2-Tetrachloroethane

Bromobenzene

Conclusions

One or more VOCs were frequently detected in urban stream samples.

More VOCs were detected in urban stream samples in cooler months (median of 7 VOCs) than in warmer months (median 

of 5 VOCs).

A large number of individual VOCs (56) were detected at least once in urban stream samples.

Gasoline hydrocarbons are the most frequently detected compounds in urban streams.

Most concentrations are less than 1 microgram per liter.

No VOCs had concentrations greater than USEPA’s Maximum Contaminant Levels or Health Advisory Levels.

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References

BTEX (benzene, toluene, ethylbenzene, and xylenes), other gasoline-related 

hydrocarbons, and gasoline oxygenates were detected more frequently in 

cooler months.

Compounds used in organic synthesis, fumigants, and refrigerant compounds 

also were detected more frequently in cooler months.

Solvents and trihalomethanes did not differ markedly between the warmer 

and cooler months.

•

•

•

Twenty-nine VOCs not detected in urban streams 

(from Seaber and others, 1987) listed by predominant use/source group

Aberjona River, Winchester, Massachusetts.

(Photograph by K.W. Campo, U.S. Geological Survey)

Lopes, T.J., and Price, C.V., 1997, Study plan for urban stream indicator sites of the National Water-Quality Assessment 

Program: U.S. Geological Survey Open-File Report 97–25, 15 p.

Seaber, P.R., Kapinos, F.P., and Knapp, G.L., 1987, Hydrologic unit maps: U.S. Geological Survey Water-Supply Paper 2294, 

63 p.

U.S. Environmental Protection Agency, 2004, 2004 Edition of the drinking water standards and health advisories: Washington, 

D.C., Office of Water, EPA 822-R-04-005.