Willamette Water Supply Program


willamette water supply yellow pipes on truck

Pipe Specifications:

Awarded four work packages thus far totaling over 20,000 LF of 66” Engineered Steel Pipe with Cement Mortar Lining and Polyurethane Coating.




Tualatin Valley Water District, the City of Beaverton, and the City of Hillsboro

Engineer Firm:

Stantec, Program Manager


Kerr Contractors, Emery & Sons, and Moore Excavation

Steadily underway, the Willamette Water Supply Program (WWSP) will provide a new water source for the planned growth areas in Washington, Multnomah, and Clackamas Counties in Oregon. When complete in 2026, the WWSP will be one of Oregon’s most seismically resilient water systems built to better withstand natural disasters, protect public health, and speed regional economic recovery through restoring critical services more quickly.

Thirty miles of pipeline will weave through the three counties, and bring water from the Willamette River in Wilsonville. A raw water intake will pump water to a new state-of-the-art water filtration plant where multiple treatment processes will produce high-quality drinking water. The system will pump drinking water to reservoir facilities on Cooper Mountain, where a gravity-fed system will transport water to customers and an additional storage facility.

Northwest Pipe is currently producing pipe for multiple work packages for this $1.2 billion project. Thus far, we have been awarded four work packages that mainly include 66” engineered steel pipe with cement mortar lining and polyurethane coating in varying wall thickness from 0.313- to 0.375-inch thick.

Owners of the project selected steel pipe due to its natural resilience during a seismic event. The system is engineered to better withstand natural disasters and the impacts of a large earthquake so that water service can be restored quickly to support emergency services and the community.