Well #6 Pumping Station & Society Road Treatment Plant — East Lyme, Connecticut

Well Permitting — LEI's hydrogeologists identified a high yielding, confined stratified drift aquifer as a significant source of new water for the town. LEI designed a 16" X 36" gravel packed well, screened between 85 and 115 feet below grade with a safe yield of 600 GPM. LEI conducted extended duration aquifer pump tests, completed three-dimensional groundwater modeling, and conducted extensive environmental studies to obtain a DEEP Water Diversion Permit for this source.

Treatment Plant Schematic Design — LEI worked closely with the Water Department and First Selectman to select the optimum location for the pumping station and treatment plant building, which was complicated by the well site being adjacent to a town school. The plant was designed to treat not only the flow from Well #6, but also to be expandable to also treat adjacent Well #1 in the future.

Chemical storage and feed facilities were provided for potassium permanganate, fluoride, and phosphate, while bulk storage facilities were provided for sodium hydroxide, and in the future for liquid chlorine. Filter backwash water was connected to the town sanitary sewer system via four equalization basins and an air gap structure.

Pump Station Features — A 36' X 52' brick-faced block building houses the well and pump, chemical storage, and three 9-foot diameter manganese greensand filter vessels. The building was designed to architecturally match the newly constructed Junior High School. A vertical turbine well pump is controlled by a variable frequency drive unit, which allows the town to vary the pumping rate, especially during filter backwashing.