Are best-management-practice criteria really environmentally friendly?

In the 1990's, a number of best management practices (BMPs) manuals have be en developed that address the control of urban runoff to protect receiving water quality. More recently, several papers have investigated the effectiv eness of these BMPs in protecting small urban watercourses, and have conclu ded that they do not. Investigations of both design practices and effective ness reveals that there is a lot of ignorance in the scientific and enginee ring community about what constitutes a properly designed BMP and what it r eally achieves, with respect to environmental protection. This paper discus ses the state-of-practice in BMP design in the United States and points out its strengths and weaknesses with respect to real protection of the downst ream receiving water environment. The paper recommends an approach to desig n criteria development that can be applied over a wide variety of climatolo gic, topologic, and geologic conditions to protect receiving waters systems .