Combined Sewer Overflow Facilities Plan for the Cleveland Westerly District

The Northeast Ohio Regional Sewer District (NEORSD) is the agency responsible for wastewater treatment in the metropolitan Cleveland area. Within its jurisdiction are three wastewater treatment facilities, interceptors sewers and combined sewer overflows. As a part of NEORSD's National Pollutant Discharge Elimination System (NPDES) permit requirement, NEORSD is undertaking the lead role in combined sewer overflow (CSO) management. One of several CSO facilities planning efforts has been completed resulting in recommendations for a comprehensive CSO control plan for the Westerly service area. This is one of several comprehensive plans that will culminate with a NEORSD District-Wide Long Term CSO Control Plan (LTCP).The Westerly service district is approximately 10,000 acres. It is bound by four receiving waters; Rocky River to the west, Big Creek to the south, Cuyahoga River to the east and Lake Erie to the north, the area is served by four interceptor systems and various regulating structures to maximize wet weather capacity in the collection system. Over 70 fixed weir regulating structures, 8 automated regulators, and 8 hydrobrake structures are operated to route flow to the Westerly WWTP for treatment. Located on Lake Erie, the facility is designed to provide treatment to flows up to 100 million gallons per day (mgd). NEORSD also operates a CSO Treatment Facility (CSOTF) to treat Westerly District CSOs. The CSOTF, adjacent to the Westerly WWTP, functions both as a storage basin and treatment facility capable of storing 6.0 million gallons (mg) of CSO for full treatment at the WWTP or provide primary treatment of CSO for up to 300 million gallons per day (mgd). Twenty-five CSOs are located throughout the Westerly District to provide relief to the collection system.Following a rigorous study and characterization of Cleveland's complex collection system, a CSO control plan estimated at 126 million has been recommended. The plan includes several technologies to maximize use of the existing system as well as new facilities, which will control CSOs to the desired level.