Heavy rains flowing through the Ohio city of Springfield’s combined sewer system overwhelmed the wastewater treatment plant. The city averaged 50 to 70 CSOs per year, discharging up to 90 mgd to the Mad River.In 2012, the city agreed with the Ohio EPA to build a 100 mgd high-rate treatment wet weather clarifier and to have the agreement added to its NPDES permit. The agency gave the city a July 2015 deadline.The review committee evaluated bids and selected the WWETCO FlexFilter compressible media filtration system from WesTech Engineering. “The technology was brand new,” says Bill Young, acting plant superintendent. “Only
