This project consisted of constructing a new 400 MGD Raw Water Pump Station and support facilities located on the west shore of Lake Fork in Wood County, Texas. BAR constructed all of the 30,000+ CY cast-in-place concrete structure utilizing its on-site concrete batch plant. The pumping system installed consisted of four, 5,500 HP, 13.2 KV horizontal split case centrifugal pumps discharging into exposed steel discharge lines that climbed vertically inside the pump station then turned horizontal, exited the pump station, and tied into buried discharge headers outside the station. This design allowed for expansion of up to a total of 10 pumps. Two soft starters and two variable frequency drives power these four pumps. The suction and discharges for these pumps include 54” ball valves and 36” pump control cone valves. The interior discharge piping was hydrostatically tested at 259 psi. Other mechanical systems installed by BAR under this project include an intake screen and purge system, flume dewatering pumps, a hydrant supply pump, sumps pumps, a pump motor cooling water system, surge tanks & compressors, a bridge crane, and a sodium hypochlorite feed system. Outside of the pump station, the discharge headers pass through a buried, cast in place valve vault housing 108” butterfly valves. BAR also constructed several separate structures including an operator house, a maintenance building, and a boat ramp. BAR installed an extensive vertical excavation support system and dewatering system due to the seventy plus foot depth excavation, sandy soil, and proximity to the lake. BAR self-performed the on-water excavation of the Pump Station’s intake channel utilizing a track backhoe mounted to a barge. This channel excavated material was side-cast and remained in the lake. Additionally, BAR removed the earthen retaining berm that resulted in the initial flooding of the pump station’s intake. Functionally, this facility is able to be controlled locally or remotely by SCADA.
After initial commissioning, it was discovered that the original design required major modifications to the discharge piping including replacing butterfly valves with check valves. BAR worked with the Owner and Engineer to troubleshoot and ultimately rework the discharge piping so that the pump station functioned correctly.
