Spanaway is located in Pierce County, Washington approximately fifteen miles south of Tacoma. The Spanaway community was experiencing difficulties with manganese in their water distribution system. Tonka Water, a U.S Water Brand, was chosen to provide a new system based on quality of equipment and level of expertise.
The water treatment system includes an OptaCell Plus™ pressure filter system and high rate IMAX™ media. The Spanaway Water Company has a 900 gpm system for manganese removal using an 8’x15’ 3-cell OptaCell Plus filter with IMAX media at 8.2 gpm/sq ft. loading rate. This project was designed to fit in a very small footprint.
Chlorine is utilized to keep the media activated during the filtration process. Manganese solids are accumulated in the media bed, which is backwashed intermittently to remove these solids. The OptaCell Plus filters are designed with isolated cell compartments above and below the underdrain for a total of three individual filter cells. This filter cell design allows for an individual cell to be backwashed or taken completely off line while the others remain online. Each filter cell supplied includes the Simul-Wash™ backwash process. This backwash system provides tremendous backwash savings through decreased backwash water usage compared to other pyrolusite filter systems.