Program Overview

The Willamette Water Supply System Commission (WWSS Commission) is an Oregon intergovernmental entity formed by Tualatin Valley Water District (TVWD), the City of Hillsboro, and the City of Beaverton.

The WWSS Commission was formed to build the Willamette Water Supply System (WWSS) in response to planned growth in their service areas. The WWSS will provide an additional, resilient water supply for Washington County.

When complete, the WWSS 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.

The Willamette River, one of Oregon’s largest rivers, is the WWSS’s new supply source. The raw water intake is located at the Willamette River Water Treatment Plant in Wilsonville. From there, raw water will be pumped to the WWSS Water Treatment Plant, a new state-of-the-art water filtration plant where multiple treatment processes will produce high quality drinking water. Drinking water will be pumped to reservoir facilities on Cooper Mountain, then will be gravity-fed to additional storage and customers in the TVWD, Hillsboro, and Beaverton service areas. The new system will be completed by 2026.

TVWD has been designated the Managing Agency for the WWSS Commission, and TVWD operates the Willamette Water Supply Program (WWSP) to plan, design, and construct the WWSS.

The Willamette Water Supply Program team is making great progress:

  • TVWD and City of Hillsboro secured $616.6 million in federal financing through the Water Infrastructure Finance and Innovation Act (WIFIA). This financing will lead to millions of dollars of savings for TVWD and City of Hillsboro ratepayers.
  • Construction on three sections of the pipeline (3.75 miles) is complete – 124th Avenue near Tualatin, Kinsman Road in Wilsonville and a segment of the South Hillsboro Pipeline Project under Cornelius Pass Road, south of TV Highway.
  • U.S. Army Corps of Engineers and Oregon Department of State Lands approved the Program’s environmental permits. Land use permitting is in progress for various elements of the Willamette Water Supply Program.

We appreciate the continued cooperation of all the WWSP pipeline and facility neighbors who have allowed access to their property for environmental and geologic studies. Limited access to private property bordering the pipeline route may be requested in the future by Program staff in order to finalize the pipeline design.

For those with property bordering water facilities, we will be in touch with you as our plans progress and if an easement on your property will be needed.

The pipeline route remains a work in progress and will continue to be refined as the design develops.

Program Map & Schedule

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Our Reliable Water

Efficient Regional Coordination

“We’re fortunate to have coordination among our regional water providers, like the Tualatin Valley Water District and the City of Hillsboro, to make sure we have a safe, resilient water supply as the region grows.” ----Councilor Kathryn Harrington, Metro Council District 4

Program Timeline

Developing the new Willamette water source will take over a decade.

Willamette Water Supply Program

Willamette Water Supply Program