Washington, D.C. — The U.S. Environmental Protection Agency (EPA) released "Greening CSO Plans: Planning and Modeling Green Infrastructure for Combined Sewer Overflow (CSO) Control" to provide municipalities and sewer authorities with tools to help quantify green infrastructure contributions to a CSO control plan. Communities with combined sewers often view green infrastructure as an attractive way to reduce stormwater flows going into their sewer system, thus helping to reduce capital and operational costs at publicly owned treatment works.
EPS said Greening CSO Plans will help communities make cost-effective decisions to maximize water quality benefits. This resource explains how to use modeling tools such as EPA's Storm Water Management Model (SWMM) to optimize different combinations of gray and green infrastructure to reduce both sewer overflow volume and number of overflow events.
More information on CSO plans and remedies is available at http://water.epa.gov/infrastructure/greeninfrastructure/gi_regulatory.cfm#csoplans.