What is a Combined Sewer and Combined Sewer Overflow?

Combined Sewers are underground pipes and tunnels that gather wastewater from homes and businesses and rainwater and snow-melt from roofs and driveways. This water is combined as it flows to Lakewood’s wastewater treatment plant.  

This design was common a century ago and, under normal circumstances, helps keep pollution out of the Rocky River and Lake Erie. During heavy rain or snow events, however, this infrastructure was designed to overflow via designated overflows, which can discharge pollutants to our community waters.

Combined Sewer Overflows are required under the federal Clean Water Act to be controlled to only activate in limited circumstances.  This is one reason why the City of Lakewood is investing in several important projects to improve system performance.