Constantine Engineering provided engineering design and construction management services for Okaloosa County Water and Sewer Department's (OCWS) 8.5 MGD (peak flow) Eglin Main Pump Station (PS) and 2.0 MGD (peak flow) Plew Pump Station; utilities that convey all wastewater previously being received and treated at the Eglin AFB to the Okaloosa County Arbennie Pritchett Water Reclamation Facility (WRF).
The Eglin Air Force Base (Eglin) and the Okaloosa County Water and Sewer Department (OCWS) previously entered into contract in July of 2009 to receive and treat wastewater from various locations. OCWS was requested to design and construct a new conveyance system to replace the two main wastewater treatment facilities located on the Eglin main base; diverting all of the wastewater to OCWS Arbennie Pritchett WRF. The overall design and construction included two submersible lift stations, 3.5 miles of 24" force main (FM), and 3.6 miles of 16" force main.
The scope of the Main PS and FM phases included a new wetwell system, four 160 hp submersible non-clog pumps and variable frequency drives. All controls were elevated and housed within a prefabricated precast electrical building with a diesel driven emergency generator. The pump station and discharge piping were designed to transmit a peak flow of 6.0 million gallons per day (MGD). The anti-floatation designed RFP wetwell was 14" diameter x 22' deep. Pumps were VFD driven controlled with PLC and level transducer controls. Secondary backup floats are included along with two back-up soft start drives. All operations are controlled with local HMI and monitored remotely through fiber connected SCADA. All internal discharge piping, guiderails and pipe supports were constructed of 316L stainless steel. The 3.5 miles of 24" force main included 1925' of directional drilled HDPE pipe and 300' of jacked 36" steel casing under State Road 85.
The scope of the Plew PS and FM phases included retrofitting an existing concrete wetwell with three new 40 hp submersible non-clog pumps; new motor control center; emergency generator. The pump station and discharge piping were designed to transmit a peak flow of 2.0 MGD. Pumps were soft start PLC controlled using level transducer controls with secondary backup floats. The 3.6 miles of 16" force main included 710' of directional drilled HDPE pipe and 130' of jacked 36" steel casing under State Road 85. The new FM runs directly through the main base housing and emergency care facilities with directional drilling under the primary base access gate parkway. Installation required coordination with daily base activities and missions, temporary wastewater bypassing and MOT of FDOT and Military controlled roadways.