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An effort to build new raw water facilities for the west side of the Portland-metro area is well under way in Wilsonville.

The facilities are at the site of the existing Willamette River Water Treatment Plant, which was developed in partnership between the city of Wilsonville and Tualatin Valley Water District in 2002. It was designed and built with the intention of future expansion, which is now coming to pass.

Now, the Willamette Water Supply Program – a partnership between the Tualatin Valley Water District and the cities of Beaverton and Hillsboro – is carrying out this expansion as part of a massive $1.3 billion project involving construction of over 30 miles of pipeline, a new water treatment plant in Sherwood, pump stations, and other infrastructure to supply water to customers in unincorporated Washington County as well as Beaverton and Hillsboro.

The raw water intake facilities being built by general contractor Kiewit Corporation consist of expanded or upgraded fish screens, an intake pipe, a caisson, a pump station building and related equipment. Once completed, raw water from will be pumped through a 66-inch pipeline from Wilsonville to a new state-of-the-art water filtration plant in Sherwood’s Tonquin Employment Area. Ground is scheduled to be broken on that plant later this year.

In Wilsonville, part of the work also includes seismic earthwork. It’s scheduled for completion in June.

Construction of the raw water facilities is being done in phases; completion is expected by 2024. The full Willamette Water Supply Program effort will not wrap up until at least 2026.

Right now, crews from Condon-Johnson & Associates, Pacific Foundation, Kiewit Corporation and subcontractors are involved in drilling related to the seismic earthwork on the lower site near the river. Preparation is under way for installation of the southern end of the 66-inch pipeline.

On the upper (north) side of the site, crews last month began installing new water and sewer utilities and connections to existing utilities. Those pieces will serve a new electrical building that provides power for the pump station and other infrastructure.

Meanwhile, Arrowhead Creek is receiving a trenchless crossing. Crews are building and excavating the launch and receiving shafts. Work on the trenchless pipeline crossing itself is set to begin in April.

Late last month, workers began installing a large underground vault (to hold a large meter and valves) in the northwest corner of the upper side of the site.

To learn more about the project, visit: .