Bruce Cahoon Water Treatment Plant, Harwich
DCI staff helped the Town of Harwich complete a new 6 MGD water treatment plant.
The Town of Harwich had been planning for the construction of a new iron and manganese filtration treatment plant for several years. The proposed plant was designed for 6 million gallons per day (MGD). The new plant will treat the groundwater effluent from Well Field No. 1, the future flow from Well Field No. 2.
The Massachusetts DEP reviewed the 6 MGD design in the fall and winter of 2009 and issued their Approval to Construct a Water Treatment Facility (BRP WS 24) in February 2010.
DCI staff assisted the Town in public bidding and overseeing the construction of the project under M.G.L. in two phases – a Ch. 30 water main project and a Ch. 149 building project. The initial phase included construction of 7,100 linear feet of 16-inch-diameter water main in March 2010. In summer 2010, the Water Department solicited bids for the vertical construction of the plant and tie into Phase 1.
In September 2010, the Town received eight bids. A Notice to Proceed with construction was issued in October 2010 and the plant came online in November 2011. The new 6 MGD treatment plant consists of a 4,700 square foot metal span structure, two residual lagoons, five iron and manganese removal filters, process piping, NaOCl and NaOH chemical feed rooms and associated MEP and HVAC equipment. DCI staff provided full-time construction oversight and resident engineering services. The oversight and resident services included shop drawing review; design associated with a pre-cast blow-off chamber and revised civil site plans, requisition review and documenting general observations that work has been completed in accordance with project plans and specifications.