The City of Clyde, Ohio, in order to meet the requirements of a consent decree from the Ohio EPA, installed a one-million-gallon flow equalization basin on the grounds of the City’s wastewater treatment plant. The basin’s inside dimensions measure 120 ft long x 100 ft wide x 14 ft deep. During high incoming flow events, excess flow is screened in the combined sewer overflow (CSO) diversion chamber and is directed to the basin by gravity. Plant personnel can drain the basin by gravity using the plant’s supervisory control and data acquisition (SCADA) system. An automated tipping bucket flushing system is used to flush accumulated solids and debris from the basin floor.
The monolithic placement of a 1,950 cubic yard mat foundation for the bottom of the equalization basin was 4-ft thick x 105-ft wide by 125-ft long and use slag cement helped to reduce thermal stress in the mass concrete. Slag cement was used at 40% replacement level in the mat foundation basin floor and at 25% replacement in basin walls. The aggressive environment this wastewater treatment application entails requires a durable concrete. Use of slag cement in basin floor and walls met specified strength criteria, provided desired sulfate resistance, reduced permeability, and reduced susceptibility to alkali silica reaction.
Project credits: City of Clyde, Ohio, Owner; GGJ Inc, Engineer; Adena Corporation, Contractor; Huron Cement Products Co., Inc., Concrete; St Marys Cement Inc. (U.S.), Slag Cement.