Colfax Water Treatment Plant Project
A Major Investment in Placer County’s Water Future
Construction is underway on the new Colfax Water Treatment Plant—an important investment in reliable, safe drinking water for foothill communities in central Placer County. As PCWA’s first new treatment facility in more than a decade, the project reflects a long-term commitment to regional water reliability, smart planning, and sustainable infrastructure.
When complete, the $36 million plant will more than double the community’s current treatment capacity and serve as a cornerstone project that supports a broader Colfax to Applegate regionalization program for un-served and under-served areas along the Interstate 80 corridor.
About the Project
Location: Just outside of downtown Colfax, offering safer access and room for expansion
New Capacity: Increasing from 1.24 to 2.0 million gallons per day, expandable to 3.0 MGD
Construction Timeline: Began June 2025, expected to take approximately 2.5 years
Project Cost: $36 million
Funding Support: Includes a $10 million zero-interest loan and $2.5 million in principal forgiveness from the State Water Resources Control Board
The new plant will replace the original Colfax Water Treatment Plant, built in 1958 and nearing the end of its service life. The new facility is designed with scalability and efficiency in mind, helping ensure a secure water supply today while planning for the needs of tomorrow.
Benefits to the Region
The Colfax Water Treatment Plant will deliver long-term benefits for both existing customers and foothill communities by:
- Improving water reliability in foothill communities like Colfax, Shady Glen, Heather Glen, and Weimar
- Supporting PCWA’s voluntary consolidation program, which helps small, struggling water systems connect to a larger network with more resources
- Enhancing system resilience to drought and emergency situations
- Providing operational flexibility to move water across service areas as needed
- Increasing fire protection capacity with upgraded infrastructure
Regional Strategy
This project is the first phase in a larger, multi-step effort to modernize PCWA’s water treatment infrastructure along the I-80 corridor. It will be followed by the planned Ophir Water Treatment Plant, a larger facility scheduled to begin construction in 2026. Together, these two plants will strengthen PCWA’s treated water delivery system, supporting planned growth and increasing the agency’s ability to respond to future challenges.
A Partnership Approach
The Colfax Water Treatment Plant is being delivered through a strong local-state partnership. Funding is made possible in part by the State Water Resources Control Board through California’s Drinking Water State Revolving Fund, which provides low-interest and zero-interest financing for critical drinking water projects. This funding structure helps PCWA move forward with major infrastructure improvements while protecting local ratepayer funds.
California Required Disclosure: Funding for this project has been provided in full or in part through an agreement with the State Water Resources Control Board. California’s Drinking Water State Revolving Fund is capitalized through a variety of funding sources, including grants from the United States Environmental Protection Agency and state bond proceeds. The contents of this document do not necessarily reflect the views and policies of the foregoing, nor does mention of trade names or commercial products constitute endorsement or recommendation for use.
