Targeting treatment technologies to address specific stormwater pollutants and numeric discharge limits

Stormwater treatment is entering a new phase with stormwater management systems being required to meet specific numeric objectives, as opposed to the historic approach of meeting guidance-document-provided percent removal rates. Meeting numeric discharge requirements will require designers to better understand and apply the physical, chemical, and biological processes underpinning these treatment technologies. This critical review paper focuses on the potential unit treatment operations available for stormwater treatment and outlines how to identify the most applicable treatment options based on the needed pollutant removal goals.

► Targeting runoff treatment for specific pollutants and numeric limits is possible.
► Stormwater chemistry is complex and affects treatability.
► Water chemistry and treatability theory can guide stormwater device designs.