Innovative Stormwater Treatment Technologies: Best Management Practices Manual

Urban stormwater carries a number of pathogens, nutrients, heavy metals, sediment, and other contaminants as surface runoff flows over land. The increase in impervious or paved surfaces associated with development in urban areas reduces the natural infiltration of precipitation into the ground. With impervious cover, precipitation collects and carries contaminants before draining into nearby surface waters. Stormwater runoff from paved surfaces in developed areas can degrade downstream waters with both contaminants and increased volumes of water. This publication aims to make information on innovative stormwater treatment technologies more available to New Hampshire’s urban planners, developers, and communities. Traditional runoff management techniques such as detention basins and infiltration swales may be preferable, but are not always practical for treating urban stormwater. Lack of space for natural solutions is often a problem in existing developed areas, making innovative treatment technologies an attractive alternative. Mostly designed for subsurface installation, urban “retrofits” use less space than conventional methods to treat stormwater. This manual provides information on the innovative stormwater “retrofit” technologies currently available for use in developed areas in New Hampshire