As one of the three largest pump stations serving the City of Hermitage and surrounding areas, the Pine Hollow Pump Station needed to be replaced after a series of infrastructure failures and an overflow event. This station, constructed in the early 1970s and last upgraded over 30 years ago, was dealing with significant growth and inflow/infiltration (I/I) affecting flows from the northern drainage area of the region. Following a comprehensive review by RETTEW and the Hermitage Municipal Authority, the decision was made to completely replace the Pine Hollow Pump Station and incorporate the Authority’s first dedicated monitoring station for I/I.

The challenging site was adjacent to steep terrain and floodplain, which limited accessible working areas. As key conveyance infrastructure, the project required continuous operations of the existing pumping and control systems while the new pump station was constructed next to the existing system. With a combined capacity of 4.2 mgd, the upgraded Pine Hollow Pump Station cost approximately $4 million dollars and was constructed over a period of 15 months. RETTEW handled all aspects of the capacity and hydraulic evaluation, Pennsylvania Department of Environmental Protection permitting, and detailed design. Further, RETTEW provided for public bidding and construction administration of the project.

Additional improvements included replacing the emergency power and automatic transfer switch, integrating I/I monitoring, rehabilitating controls, and tying into the Authority’s SCADA system. The buried infrastructure was carefully developed in cooperation with a precast concrete manufacturer to allow for access and placement on the narrow site and to incorporate maintenance features desired by the Authority.