What is the primary function of Active Treatment Systems (ATS) in stormwater management?

What is the primary function of Active Treatment Systems (ATS) in stormwater management?

• A. Add chemicals to facilitate flocculation, coagulation and filtration of suspended sediment particles.
• B. Remove all dissolved pollutants.
• C. Increase water temperature to speed settling.
• D. Filter without using chemicals.

Answer: (B)

Active Treatment Systems are designed to target dissolved pollutants in stormwater, rather than just the suspended solids that settle out physically. They use active processes—such as chemical dosing, adsorption, precipitation, and sometimes specialty media—to remove contaminants that stay dissolved and wouldn’t be captured by simple filtration or gravity settling. This focus on dissolved pollutants is what makes them distinct from systems that primarily address sediment loads. The option describing removal of all dissolved pollutants captures this purpose, as ATS are meant to actively remove dissolved contaminants that passive methods can miss. In contrast, adding chemicals to mainly help flocculation and coagulation targets suspended particles, not the dissolved fraction; increasing temperature to speed settling isn’t a primary mechanism for ATS, and filtering without chemicals relies on passive processes rather than the active treatment approach that ATS embodies.

Active Treatment Systems are designed to target dissolved pollutants in stormwater, rather than just the suspended solids that settle out physically. They use active processes—such as chemical dosing, adsorption, precipitation, and sometimes specialty media—to remove contaminants that stay dissolved and wouldn’t be captured by simple filtration or gravity settling. This focus on dissolved pollutants is what makes them distinct from systems that primarily address sediment loads.

The option describing removal of all dissolved pollutants captures this purpose, as ATS are meant to actively remove dissolved contaminants that passive methods can miss. In contrast, adding chemicals to mainly help flocculation and coagulation targets suspended particles, not the dissolved fraction; increasing temperature to speed settling isn’t a primary mechanism for ATS, and filtering without chemicals relies on passive processes rather than the active treatment approach that ATS embodies.