|Urban Stormwater Management in the United States (2008)|
Report in Brief
The rapid conversion of land to urban and suburban areas has profoundly altered how water flows during and following storm events, putting higher volumes of water and more pollutants into the nation's rivers, lakes, and estuaries. These changes have degraded water quality and habitat in virtually every urban stream system. To help address this problem, Congress in 1987 amended the Clean Water Act, expanding the U.S. Environmental Protection Agency's (EPA) oversight from about 100,000 point source permittees (wastewater discharged from industries and sewage treatment plants) to more than 500,000 permittees in order to encompass stormwater discharges from municipal areas, industry, and construction sites. Adding to the challenge of more permittees, it is much more difficult to collect and treat stormwater than wastewater. In light of these challenges, EPA asked the National Research Council to review its stormwater program. The report finds that the program will require significant changes if it is to improve the quality of the nation's waters. This report calls for an entirely new permitting structure that would put authority and accountability for stormwater discharges at the municipal watershed level. A number of additional actions, such as conserving natural areas, reducing hard surface cover (e.g., roads and parking lots), and retrofitting urban areas with features that hold and treat stormwater, are recommended.