Placer County’s water system is in for a major tune-up. The Placer County Water Agency has mapped out nearly $295 million in capital projects that will stretch from the foothills to the freeway, rebuilding plants, rehabbing buried pipes and trying to stay ahead of both growth and wildfire season.
The agency rolled out the effort on March 4 with photos and a short newsletter that spotlighted the new Colfax water treatment plant now under construction, a planned 10-MGD Ophir plant to serve western Placer, and a long list of pipeline fixes, including crossings buried beneath Interstate 80. Agency leaders are pitching the spending as a long-haul “renewal-and-replacement” push meant to keep taps running and hydrants ready as the county builds out.
What PCWA Posted
In its March 4 update on Placer County Water Agency on Facebook, PCWA laid out roughly $295 million in capital work that centers on new and upgraded treatment plants along with a multiyear pipeline rehabilitation program.
The post notes that PCWA operates around 50 pipeline crossings under Interstate 80 between Roseville and Alta, and that the first phase of that rehabilitation effort is slated to begin in 2026. On PCWA’s website, the agency describes the broader effort as a renewal-and-replacement program that “repairs and replaces aging infrastructure to prevent failures and keep service reliable 24/7.”
Colfax And Ophir Timelines
The Colfax plant is first up in the construction queue. The replacement project broke ground in 2025 and will boost treatment capacity from about 1.2 million gallons per day to roughly 2.0 MGD, with design room to eventually expand to 3.0 MGD, according to coverage of the agency announcement by ACWA.
On the western side of the county, the Ophir Water Treatment Plant is planned as a phased build. PCWA staff told the board that Phase 1 will add 10 MGD of capacity, with the agency targeting full operation by 2030 after bidding and construction, according to reporting in Placer Sentinel.
Old State Highway Project And Neighborhood Impacts
Below the pavement, PCWA is pairing up with the South Placer Municipal Utility District for the Old State Highway Pipeline Replacement Project. The plan is to replace and upsize aging water mains, swap out older hydrants, and replace sewer mains and laterals along the corridor, with trenching and paving timed together so crews are not tearing up the same street twice, according to SPMUD.
Residents and commuters will feel some of that work. Officials are warning drivers to expect alternating one-way traffic and intermittent closures while construction moves through the area.
How The Work Is Being Paid For
Agency materials and budget reporting indicate that the extra capacity is largely funded through developer-paid water-connection charges so that “growth pays for growth,” while the renewal-and-replacement side is backed by customer rates and targeted grants, as outlined in budget coverage by Placer Sentinel.
The Colfax replacement landed a significant boost from the State Water Board’s SAFER program. The project received a $10 million zero-interest loan and a $2.5 million grant, according to the State Water Resources Control Board.
What To Expect Next
PCWA says the first phase of Interstate 80 pipeline crossing rehabilitation is scheduled to kick off in 2026. As work ramps up, the agency plans to use online project pages and e-news updates to spell out detours, construction windows and timelines. Customers are being urged to track maps and schedules on PCWA’s website.
Agency leaders say that by phasing projects and coordinating closely with local districts, they intend to keep water service reliable while crews dig into the county’s aging infrastructure.
