Combined Sewer Overflow (CSO) Projects

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Combined sewers convey both storm (rain) water and wastewater (sewage) in one piping system. Historically, more than 800 communities across the United States built combined sewers once indoor plumbing became commonplace in the late 1800s.

During normal rain events with ¼-inch of rainfall or more, the combined system capacity can become overwhelmed, resulting in a mixture of storm water and wastewater overflowing into area waterways. This is referred to as a combined sewer overflow (CSO) event, which causes a threat to public health and the environment.

Our Consolidated Collection Sewer (CCS) projects are working to mitigate CSOs in the parts of Indianapolis where overflows occur and cause the greatest negative impact to our rivers, streams and treatment system as a whole.

Consolidated Collection Sewer Projects (CCS)

E. 10th Street/N. Kealing Avenue

Windsor Park

Market Street/Pine Street