23 Mile Sewer & Pump Station

The project consisted of a 1.5-mile-long trunkline sanitary sewer extension along 23 Mile Road east of Card Road to the eastern Township boundary.  The sewer was designed to serve the entire northeast corner of the Township.  The project consisted of approximately 8,000 linear feet of 10-36-inch gravity sewer, 1,300 linear feet of 20-inch force main, and a 7 cfs submersible pump station.

Spalding DeDecker (SD) provided survey, design, and construction contract administration services for the project.  The Preliminary Design Phase was done as part of a request from several property owners requiring sanitary sewer service for proposed developments within the sewer’s service district.  SD identified an outlet, determined the sewer alignment and ultimate capacity requirements, and prepared a project cost estimate.  A group of property owners used this information to develop an agreement for financing the project.

A new pump station was designed and constructed at the northwest corner of 23 Mile Road and North Avenue.  The pump station is equipped with three submersible pumps.  One pump is used to pump the expected dry weather flows of approximately 185 gpm.  Two pumps will be required to pump the maximum design flow of 3,200 gpm, with the third pump acting as a standby pump.

Flows enter the pump station through a proposed 36″ PVC gravity sewer.  The pump station lifts and discharges the flow into a 20” HDPE force main that eventually discharges the flow to a 36” gravity sewer.

The pumps are controlled based on the sewage level within the wet well.  An ultrasonic system transmits the wet well level to signal the pumps to turn on or off. Floats are used as back-up level controllers for low and high level alarms.  The pump station is connected to the Township’s existing Supervisory Control and Data Acquisition (SCADA) system.  The system is capable of logging events such as pump starts and stops, security events, and the status of various system components.

SD’s services included project estimates and consultations, topographical survey, detailed site, mechanical, and structural drawings and specifications, obtaining all construction permits and approvals from local and state agencies, and easement documentation preparation.  SD also assisted the Township in acquiring and reviewing bids.  As part of the project, SD also performed the construction contract administration on the project.

Funding

The majority of this project was funded privately by a group of property owners who were developing the property within the sewer’s service district.  The Township provided funding for the submersible pump station and force main portion of the project.