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Assessing the performance of wet swale (wetland channel)

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

photo of swale with water

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

Swales retain solids and associated pollutants by settling and 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. If the swale is designed for infiltration, see Assessing the performance of bioretention.

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