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Assessing the performance of bioretention

Green Infrastructure: Bioretention practices can be an important tool for retention and detention of stormwater runoff. Because they utilize vegetation, bioretention practices provide additional benefits, including cleaner air, carbon sequestration, improved biological habitat, and aesthetic value.

photo of bioretention with water

A properly functioning bioretention practice should drain within 48 hours of a runoff event

Bioretention practices include biofiltration and bioinfiltration best management practices. Biofiltration (bioretention with underdrains) is designed to retain solids and associated pollutants by filtering. A typical method for assessing the performance of of BMPs with underdrains is therefore measuring and comparing pollutant concentrations at the influent and effluent. Bioinfiltration (bioretention BMP without underdrains) are more difficult to assess, although considering only potential impacts to surface waters, a properly functioning infiltration system is considered to be highly performing.

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