The North Acton Water Treatment Plant was completed in September of 2009 and has a capacity of .5 MGD. Raw water from the Marshall and Kennedy sources is pumped to the treatment facility where the water is first strained and aerated. The aeration process raises the pH of the water and provides the initial oxidation of the iron. The aerated water then flows to the rapid mix chambers for chemical addition, specifically: potassium permanganate for oxidation of the manganese, potassium hydroxide for additionalpH adjustment; and aluminum chlorohydrate for coagulation. The chemically treated water then flows to the flocculation tanks to form floc and then into the equalization tanks. From there the pretreated water flows into the mebrane tanks and is filtered through the ultrafiltration membranes via the suction of the permeate pumps. This permeate water is discharged into the clearwell where it is further treated with sodium hypochlorite for disinfection and sodium fluoride for fluoridation. After traveling through a series of baffles, the water is pumped into the distribution system.
Backpulse and Clean-in-Place (CIP) tanks are also included for the backwashing and cleaning of the membranes. In general, the backwash water from the process is sent into the recycling tanks. From there the supernatant is pumped to the rapid mix tanks for additional treatment and the collected solids are sent to the on-site lagoons.