Stormwater filtration Best Management Practices
Filtration Best Management Practices (BMPs) treat urban stormwater runoff as it flows through a filtering medium, such as sand or an organic material. They are generally used on small drainage areas (5 acres or less) and are primarily designed for pollutant removal. Filtering BMPs are designed only for pollutant removal, and do not reduce peak flows for flood control or channel protection. These BMPs have not been widely applied in cold climates (CWP, 1997), but some filtering systems have the potential to be valuable BMPs in these regions.
The following practices typically employ an underdrain, which captures most of the runoff that enters the BMP. For information on these BMPs with no underdrain, see Infiltration practices.
Other filtration BMPs, including pre-treatment practices
- Green roofs (+)
- Turf
- Vegetated filter strips
- Manufactured devices
- MIDS Calculator screen shots for inputs for bioretention without an underdrain (bioinfiltration). Click on an image for enlarged view.
Screen shot showing Watershed tab for bioretention without an underdrain. See Step 6.
- File:Permeable pavement credits underdrain.jpg
