Combined sewer overflows (CSOs) occur when storm water mixed with sewage overflows into the Maumee River, Ottawa River and Swan Creek. The City is working with the U.S. and Ohio EPAs on a Long Term Control Plan, which identifies how it will address CSOs.

The information below lists combined sewer overflows by date, location and duration. You may click on the CSO number below, or a CSO dot on the map, to see a more detailed locator map.