Welcome to the
Joint Water Commission
Delivering safe, high-quality drinking water to communities in Washington County, Oregon since 1976
Who We Are
The Joint Water Commission (JWC) is the primary drinking water supplier in Washington County, Oregon, and is responsible for treating, transmitting, and storing drinking water for more than 458,000 customers.
Four agencies share ownership in the JWC - Cities of Hillsboro, Forest Grove, and Beaverton, and the Tualatin Valley Water District (TVWD). The JWC also wholesales water to the City of North Plains.
What We Do
Treatment
Our comprehensive water treatment process includes eight steps from raw water intake to delivery of clean, fresh drinking water right to your tap. Find more details about our process here.
Storage
The Joint Water Commission’s Fernhill Reservoirs play a critical role in ensuring a reliable supply of safe drinking water. These facilities can store up to 40 million gallons.
Transmission
The Joint Water Commission (JWC) sends water to each of its five member agencies through gigantic pipes called "Transmission Lines".
Projects
The Joint Water Commission invests in infrastructure to improve treatment, transmission, storage, and seismic resilience. It also creates plans and programs to strengthen capacity and emergency readiness.
JWC News
From Disco to Drinking Water: JWC Celebrates 50th Anniversary
This year, the Joint Water Commission (JWC) celebrates its 50th anniversary, marking five decades of delivering safe, reliable drinking water to Washington County. The JWC’s Water Treatment Plant (WTP) came…
JWC Celebrates $1.09 Million Federal Grant for Seismic Improvements to Water Treatment Plant Disinfection System
The Joint Water Commission (JWC) welcomed Congresswoman Suzanne Bonamici to the JWC Water Treatment Plant on March 9, 2026, to celebrate a $1.092 million Congressional Project Funding (CPF) grant secured…
The 1996 Floods: How the JWC Kept Water Flowing During Oregon’s Worst Floods
This month marks 30 years since Oregon’s largest flood event.That winter, an unusual confluence of weather events made the floods particularly severe. Abnormally high rainfall and relatively low snowfall saturated…
Award Winning Water: The Joint Water Commission Receives Award for Source Water Protection Efforts
The Joint Water Commission (JWC) recently received an award for efforts towards protecting drinking water sources. This award from the Oregon Health Authority acknowledges protection activities that substantially lower risks…
Joint Water Commission Receives $8.9 Million Grant for Disinfection Retrofit Mitigation Project
The Joint Water Commission (JWC) recently received a Hazard Mitigation Program Grant from FEMA for a replacement disinfection facility. The current project budget is $8.9 million, with the grant covering…
Living Downstream: Eldon S. Mills Dam & Barney Reservoir
The Eldon Mills Dam and Barney Reservoir are located at the headwaters of the North Fork Trask River in Oregon’s northern Coast Range. The dam is composed of rock. It was originally…