Erie County selected KS Associates to design a solution for capacity problems at the Stonewood Sanitary Pump Station. The existing Stonewood Drive Pump Station serviced a residential subdivision comprised of 141 homes on approximately 55.7 acres. During rain events the station was overloaded causing sanitary overflows. Additionally, the force main from this pump station discharged into a sanitary sewer tributary to another overloaded pump station located on Marshall Avenue. The goal set forth for this project was to provide relief to both pump stations by upgrading the Stonewood Pump station and re-routing the effluent to a point downstream of the Marshall Avenue Pump Station.
The Stonewood Pump Station was a wet wet/dry well configuration equipped with two suction lift pumps operating at 234 gpm. In an effort to make all of the County’s pump stations consistent, the owner requested that the new pump station be configured with submersible pumps. KS Associates prepared a Preliminary Engineering Report evaluating the existing pump station, tributary area and outlining multiple solutions for both the pump station configuration and force main alignment. As a result of the report, it was decided that a new wet well would be constructed adjacent to the existing wet well. Instead of bypassing the existing wet well with a gravity sewer, the influent line to the new wet well would be installed directly into the existing wet well. This provided additional wet well storage capacity and maintained station operation during construction.
The submersible pumps selected for the new pump station were designed to provide 485 gpm. At the request of the owner the new pump motors were set for three-phase power. However, the existing power feed to the pump station was single phase. KS Associates, Inc. worked with the local electric utility company to provide three-phase power by reusing the existing forcemain easement. In order to provide relief to the Marshall Avenue Pump Station several force main alignment alternatives were evaluated. The recommended alignment routed the new force main 2,250 lineal feet (L.F.) north to the existing Pipe Creek Interceptor Sewer.
KS Associates performed customary bidding services for the Owner including distributing bid documents, issuing addenda, and attending the bid opening. The low bidder came in at $430,216, which was 8.2% below the Engineer’s Estimate.
The County requested that KS provide construction administration services and a full-time resident project representative (RPR) for the construction phase of the project. Construction started in June 2005 and substantial completion was achieved in September 2005. KS held monthly progress meetings with the contractor and the owner, processed pay estimates, reviewed certified payroll reports and processed change orders.