Stormwater treatment measures are systems designed to remove pollutants from stormwater before it reaches the storm drain system. Examples of allowable treatment measures for most projects include: bioretention areas, flow-through planters, infiltration facilities (e.g., trenches, pervious pavements, or subsurface systems), and rainwater harvesting systems. Vault-based treatment systems are only allowed at certain high-density projects that meet the Special Projects criteria described in Appendix J of SCVURPPP’s C.3 Stormwater Handbook.
Stormwater treatment measures are designed to treat a specified volume or flow of stormwater, depending on how they function. Volume-based treatment measures detain stormwater for a certain period and treat primarily through storage and infiltration. Flow-based treatment measures treat pollutants from a moving stream of water through filtration, infiltration, and/or biological processes.
To learn more about selecting, designing and sizing stormwater treatment controls, see the C.3. Stormwater Handbook.