Summary

This manual provides detailed guidance for engineers and siteplanners on how to plan and design urban best management practices (BMPs)to remove pollutants and protect stream habitats. Describes water quality and habitat impact in streams that result in uncontrolled watershed development. Contains a simple method for estimating pollutant export from development sites. Presents a series of tools to assist the site designed in selecting the best BMP option for a site. Provides detailed design guidance on seven major urban BMP practices in use in the Washington metropolitan are: extended detention ponds, wet ponds, infiltration basins and trenches, porous pavement, water quality inlets and vegetative practices. Each BMP is reviewed from the standpoint of stormwater management benefits, pollutant removal, physical feasibility, costs, maintenance requirements, and impact to the environment and adjacent communities. A list of recommended design standards that enhance BMP performance is also included.