JWC Water Treatment Plant Expansion Project

Increasing Water Capacity, Strengthening Water Infrastructure & Ensuring Clean, Reliable Drinking Water for Customers

In response to the need to provide additional water for growing communities in western Washington County, the Joint Water Commission (JWC) —owned in partnership by the Cities of Hillsboro, Beaverton, Forest Grove and the Tualatin Valley Water District — are working to complete a multi-year water treatment expansion, improvements project, and facility plan for the JWC Water Treatment Plant.

The project, a result of nearly four years of water supply planning, addresses long-term water capacity and strengthens seismic resiliency while bringing the capacity of the plant from 75- to 85-million gallons (of water) per day (mgd) by 2019.

In addition to new and enhanced water treatment capabilities increasing the plant’s treatment capacity and reliability, the project also involves strengthening water infrastructure and planning for a future plant capacity of 105-mgd. A facility plan has been developed to lay the groundwork for the immediate plant expansion as well as phased seismic improvements and expansions until ultimate plant build out.

The JWC currently treats, transmits and stores drinking water for more than 365,000 customers, and is the largest conventional water treatment plant in Oregon.

For additional information on how the project will help provide safe and cost-effective drinking water to the water service partners for current and future needs, contact City of Hillsboro Project Manager Erika Murphy at 503-615-6720 or by e-mail.

Project Details

  • Project Status: Currently under construction
  • Completion: 2019
  • Total Project Value: $35 million
  • Delivery Method: CM/GC
  • Project Manager: Erika Murphy, City of Hillsboro
  • Contractors: Jacobs (formerly CH2M) and Slayden Constructors

December 2018 Project Updates

  • December 2018 JWC WTP Expansion Project Update16” surge basin recycle piping installation is ongoing. Recycle piping distributes filter backwash water collected in the surge basin to solids drying beds and is a component of the solids handling process.
  • Installation of plate settlers at flocculation basin E were completed.
  • Installation of flocculation basin D splitter box is  ongoing. The new splitter box will allow the diversion of water from plate settled flocculation basins D, E, F, and G to new, seismically resilient filter structures.
  • Preparation for filter effluent pipeline connection to the finished water clearwell is ongoing. Clearwell connection and excavation requires the installation of temporary steel piles and welded steel bracing.
  • Filter backwash pump replacement is ongoing.
  • Installation of four new raw water pumps at the Tualatin River intake facility (Spring Hill Pump Station) is ongoing. Installation activities will continue through February 2019.

Additional Resources

  • Joint Water Commission Water Treatment Plant Expansion to 85 MGD – Package 2 – GMP Submittal: The GMP is available for review at the partner agencies: Cities of HillsboroForest GroveBeaverton and the Tualatin Valley Water District (TVWD). For questions, contact Tacy Steele at 503-615-6732.