The Ypsilanti Community Utilities Authority (YCUA) was formed in 1974 when the Charter Township of Ypsilanti and the City of Ypsilanti combined their respective water departments. YCUA purchases water from the Detroit Water and Sewerage Department and distributes it to about 112,000 people. The YCUA wastewater system includes more than 200 miles of collection sewers, more than 60 miles of interceptor sewers, almost 23 miles of sanitary force mains, 32 pump stations, and the wastewater treatment plant. The wastewater treatment plant provides tertiary treatment and disinfection before discharge to the Lower Rouge River. The design treatment capacity of the wastewater treatment plant is 51.2 mgd.
Before deciding on the 4320s, Kennedy Industries along with YCUA operations and maintenance personnel performed an extensive energy study of the aeration mixers. The old mixers varied by manufacturer, horsepower, thrust, and input kW to operate. The goal of this study was to evaluate the mixers in terms of both performance as well as energy usage. Over a couple of weeks Kennedy and YCUA personnel installed an Acuvim 2 W power monitor on one of the 4320 mixers at the plant and on each of the other manufacturer’s equipment for comparison purposes. The mixers were monitored at five-minute intervals and all electrical data was transmitted via cellular modem and sent to Kennedy’s servers so that YCUA could view the results in real time on a secure web site.