EFFECTIVENESS OF COMMONLY USED URBAN BEST MANAGEMENT PRACTICES

The United States Environmental Protection Agency (USEPA) Office of Water began the process to develop Effluent Limitation Guidelines (ELGs) for the construction and development industry five years ago in 1999. The ELGs, which will be implemented through the National Pollutant Discharge Elimination System permit program, will require the use of Best Available Technology (BAT) in the form of stormwater management and erosion and control best management practices (BMPs) to control stormwater runoff from new development and redevelopment sites. The validity and completeness of the data used as a basis for formulating the ELGs is important to the National Association of Home Builders (NAHB), because the new ELGs would impact how land is developed and, ultimately, the cost of housing. In order to assess whether sufficient information existed for drawing conclusions regarding BMP performance, PBS&J:Reviewed and analyzed the current body of knowledge of BMP effectiveness to control, reduce, or eliminate sediment, nutrients, and oil and grease from stormwater associated with land disturbance activities, andAssessed whether there are sufficient data to conclude which BMPs represent Best Available Technologies (BATs).The results of the assessment and analyses support the following major conclusions: 1) the performance efficiency of even the most commonly used BMPs to control pollutants in storm water runoff has not been tested to the extent that is needed to select BMPs that represent BAT on a widespread basis, and 2) the effluent quality of treated storm water discharges has largely been ignored in research projects designed to study storm water BMPs, so the actual impact of treated storm water discharges on aquatic systems is largely undocumented.