SW Pollutants

Stormwater Pollutants

Rain garden used for on-site stormwater management at a commercial property.
Source: LID Center
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A variety of pollutants are typically present in stormwater runoff. Industrial air pollution, automotive exhaust components, brake pad dust, pet waste, lawn fertilizers, sediments, and a host of other contaminants are combined during wet weather events in stormwater runoff. The number of pollutants and the number of sources complicate efforts to provide effective water quality improvements.

Typical Pollutant Concentrations in Stormwater Runoff

Pollutant	Concentration (mg/L)	Source
Biochemical Oxygen Demand (BOD₅)	8 – 12	Organic matter, trash
Chemical Oxygen Demand	40 – 90	Organic matter, trash
Copper	0.011 – 0.047	Automobiles, roofs
Fecal Coliform	1,000 colonies/mL	Pet waste, wastewater collection systems
Lead	0.03 – 0.18	Automobiles, industrial facilities
Total Nitrogen	0.43 – 3.3	Lawns, gardens, atmospheric deposition
Total Phosphorus	0.26 – 1.66	Lawns, gardens
Suspended Solids	50 – 100	Construction sites, roadways
Zinc	0.129 – 0.226	Automobiles, industrial facilities

Sources:

Andoh, R., Urban Runoff: Nature, Characteristics, and Control, Journal of the Institution of Water and Environmental Management, Vol. 8, August 1994.

Center for Watershed Protection, New York State Stormwater Management Design Manual, New York State Department of Environmental Conservation, August 2003. http://www.dec.state.ny.us/website/dow/toolbox/simple.pdf

Schueler, T. Controlling Urban Runoff: A Practical Manual for Planning and Designing Urban BMP, The Metropolitan Washington Council of Governments, Washington DC, 1987.

U.S. EPA, Protecting Water Quality from Urban Runoff, Nonpoint Source Control Branch, EPA-841-F-03-003, February 2003.