The Auburn Water District is seeking proposals to perform periodic operational maintenance cleaning of a total of three (3) backwash lagoons located at both 74 Walsh Avenue and 25 Southbridge Street Court Water Treatment Plants as shown below. The drinking water treatment process includes removal of iron, manganese and arsenic via greensand pressure filters from which the backwash is deposited into open lagoons. No flocking agents are used in the treatment process. The proposal shall include pricing for all work to clean, process and legally dispose of the backwash residue at an approved and licensed facility. The lagoons are rectangular shaped with sloping sides and a flat bottom. The sides and bottom of the lagoons are lined with crushed stone which shall remain in place and cleaned of accumulated backwash sediment. The depth of the residuals varies and is estimated to be at a maximum depth of approximately 5+/- feet. (see attached photos)
