To ensure the cleanest possible lake water for the Howard Avenue plant, the south intake was extended 4,200 feet farther into Lake Michigan, out of the path of contamination flowing from the Milwaukee harbor. The result is a substantial improvement in raw water quality. Ozone Disinfection Ozone replaced chlorine as the primary disinfectant when ozone systems were installed at both plants in 1998. Ozone destroys illness-causing microorganisms, controls taste and odor, and reduces chlorinated disinfection byproducts. With ozone in place, the Water Works is poised to comply with upcoming stringent regulations.
Ozone is applied to raw water before coagulation.
The ozonated water then follows the conventional treatment train of coagulation, sedimentation and filtration. The new dual media system facilitates longer filter runs and improved water quality. Further improvements in filter performance were achieved by delivering a polymer to each filter bed after backwashing. The polymer reduces the passage of particulates when a filter is returned to service after backwash. Additional Process Improvements Systems to control lead and copper corrosion were installed at both plants and have been operational since 1996.