Filters
Alternative stormwater filtration options
Filters are designed like a bioretention but without the plants. They use 100% sand for their media mix and have a defined pretreatment area.
They often have underdrains included, and filter stormwater without relying as heavily on infiltration.

5 Things to Know About Filter Practices:
- They require a two cell design: a sedimentation basin, and a filtration area
- They have proven pollutant removal
- They are ideal for commercial and industrial sites because of their ability to remove hydrocarbons and metals that tend to be present at those sites
- They are not as common as bioretention, despite their pollutant removal abilities: they have fewer cobenefits, such as aesthetics and habitat potential for native species
- They typically serve drainage areas less than one acre
Related Resources
View All ResourcesDesign Spec
Design Spec: Filtering Practices, 2011Developed by the Virginia Department of Conservation and Recreation, this design specification (Version 1.8, 2011) provides guidance on the design...
