Willow Lake WPCP Headworks and Primary Treatment Improvements

Slayden was selected as the CM/GC on this $92 MM Headworks and Pumping Plant Project for the City of Salem. This fast track project included construction of new headworks, influent and primary pump station, bar screen facility, two electrical buildings, two new primary clarifiers, effluent analyzer building, and an effluent diversion structure. Specific work components included installation of a 120’ x 220’, 50’ deep excavation, Z sheet shoring system with a double row of tie backs. Also included were ten dewateringwell points with rates in excess of ten to fifteen million gallons per day (mgd). This water was pumped to a large settling basin before being discharged to the Willamette River.

Other work components included excavation of over 100,000 cy of soils and placement of over 20,700 cy of complex concrete at numerous structures, and the supply and install of a $13 MM mechanical piping and equipment package that included thirteen flygt submersible pumps (seven of these pumps were 20” discharge with 133 HP motors). This project also included three 65’ tall barscreens, two conveyors, two washer compactors, two primary clarifiers, 35 slide gates, 30 total pumps ranging in size from 2” to 20”, approximately 40 dezuric valves many of which were electrically actuated, and mechanical piping ranging from 4” through 12”. Also, 300’ of new large diameter (96”) influent piping 30’ below grade and over a mile and a half of numerous other inner connecting plant piping runs (4” up through 60”). Slayden also managed the complex electrical, instrument, and control packages along with the startup of the facilities. Close coordination with the existing plant operation made this a successful project that was completed on time and with no interruptions to service.

Total Project Value: $92.3 million

Slayden Construction Role: CM/GC

Owner: City of Salem