Stormwater wetlands are shallow systems that collect runoff and store it in permanent pools. They are populated by marshland vegetation that help treat the water and allow pollutants to settle at the bottom like they do in natural wetlands, which allows them to support wildlife.
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Stormwater wetlands collect runoff and store it in a permanent, shallow pool. Marshland vegetation helps treat the water and allows pollutants to settle to the bottom. Because stormwater wetlands seek to imitate the functions of natural wetlands, these systems can become aesthetic assets to the community and provide habitat for local wildlife. Stormwater wetlands are often constructed in regions where native soil conditions do not allow for infiltration or where the groundwater table is exposed or close to the surface. Stormwater wetlands can also be created in low-lying areas through the use of impermeable liners to induce year-round inundated soil saturation. Wetland vegetation generally consists of open water, emergent plants, low/high marsh, and upland plants.