The Westside WWTP Effluent Disinfection involved the installation of a new chemical feed disinfection process to the existing WWTP, which was built in the 1960s. The project included an above-grade chemical feed building for the disinfection process. The building contains bulk storage tanks for sodium hypochlorite and sodium bisulfite used in treating wastewater effluent from this facility. A new below-grade chlorine contact basin was also constructed as a part of the project. This structure was 18 feet deep, 70 feet wide and 160 feet long, and it contained interior baffle walls and an adjacent drainage vault structure for draining and cleaning during seasonal usage.

All structures were on auger cast piles which ranged in size from 24 to 30 inches in diameter and were 60 to 72 feet deep. The project also included extensive electrical control system work and the integration of new control system hardware for the existing system. Whiting-Turner was successful in achieving a 10-day complete bypass of plant flows. Plant flow rates ranged from 16 to 47 MGD during our bypass operation with 12 diesel bypass pumps ranging from 6- to 18-inch pump sizes.