In February, sitting under nearly 80 inches of snow, residents of Boston dreamed of the great melt. But city planners were less excited, especially those working with the EPA. For with every great stormsnow or raineventually comes buckets of stormwater. The rivers of urban run off from man-made surfaces -- roads, freeways, sidewalks, roofed structures, parking lots, airports and industrial sites among othersare teeming with all sorts of debris -- oil, grease, pesticides, road salts, metals, bacteria and viruses, and toxic chemicals from automobiles among others. Urban terrain, unlike soil does not have the ability to filter or biodegrade contaminants like natural soil does. And the threat to human health by urban runoff is not only due to materials scoured from surfaces, but also from the infrastructure of the sewer system itself. Storm water systems are often combined with sanitary sewer systems en route to sewage treatment plants. Excessive storm water can cause this joint system to overflow, resulting in sewage contamination of waterways. Urban runoff is usually collected by storm sewers and discharged directly into waterways, and many sources of discharge go uncontrolled and untreated. Constructed Creeks is the primary reference on stormwater science and management that is intended for policy makers and active citizens, as well as scientists looking for tools to educate with.

William G. Wilson is an associate professor in the Department of Biology at Duke University. He is the author, most recently, ofConstructed Climates: A Primer on Urban Environments, also published by the University of Chicago Press.

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