About the Aqua-Filter Stormwater Filtration System
General Information Performance Data Water Quality Treatment Process Design




Back to List of Evaluated Treatments

System Performance

Water Quality Treatment
The Aqua-Filter performed moderately well at removing most analyzed pollutants from stormwater runoff. Its performance did not meet EPA’s recommended level for removal of total suspended solids. The system demonstrated a moderate ability to remove petroleum hydrocarbons and metals, but no significant capacity for nitrogen and phosphorus removal. Like the other systems monitored at UNHSC, the Aqua-Filter does not treat chloride.

The chart at top right reflects this system’s performance in removing total suspended solids, total petroleum hydrocarbons, dissolved inorganic nitrogen, total phosphorus, and zinc. Values represent results recorded over a two-year monitoring period, with the data further divided into seasonal components.

Water Quantity Control
The Aqua-Filter Stormwater Filtration System is designed to be a flow through structure. In general, compact, subsurface systems like this one do not provide peak flow reduction, or runoff volume reduction.

Maintenance
UNHSC researchers replaced the perlite filter cartridges in the Aqua-Filter unit annually, according to manufacturer guidelines. Maintenance requirements include the removal of sediments and floatable contaminants from the Aqua-Swirl, which has one manhole for inspection and clean out. The Aqua-Filter, which has two manholes for inspection and maintenance, requires the periodic replacement of the perlite filter cartridge. Filter cartridge replacement is a “confined space entry,” which requires training and a permit. Both units require frequent inspection and cleaning to maintain effectiveness.

Cold Climate
The Aqua-Filter Stormwater Filtration System’s water quality treatment and water quantity control performance showed some seasonal variations, but not enough to warrant design alterations for cold climates.