Sweetwater Authority advances PFAS pilot and preliminary design amid ratepayer quality concerns

Sweetwater Authority advances PFAS pilot and preliminary design amid ratepayer quality concernsWith a September 2026 deadline for a final design report, the California agency is accelerating treatment studies to meet 2029 federal compliance, supported by survey findings that rank PFAS mitigation as a top customer priority.

Carollo Engineers and Tetra Tech are executing a pilot study and preliminary design report (PDR) scheduled for completion by September 2, 2026.

Bench scale testing begins February 10, 2026, with pilot testing running through August 2026 to determine the optimal treatment blend.

A 2025 customer survey revealed a drop in the agency's satisfaction GPA to 2.96, with water taste and trust identified as the primary drivers of sentiment.

37% of surveyed ratepayers identified PFAS treatment as their top priority for new infrastructure projects.

The agency is preparing for EPA Maximum Contaminant Levels (MCLs) that become effective in April 2029.

Sweetwater Authority has advanced its strategy to address per- and polyfluoroalkyl substances (PFAS) contamination at the Perdue Water Treatment Plant, initiating a pilot project and preliminary design phase aimed at selecting a permanent treatment solution by late 2026. During the January 28, 2026, Governing Board meeting, staff outlined an aggressive schedule to ensure compliance with EPA regulations set to take effect in 2029. The Authority has retained Tetra Tech as the owner’s advisor and Carollo Engineers to conduct the study and design work. Tetra Tech brings significant relevant experience to the advisory role, having previously designed the largest ion exchange PFAS treatment plant for the Orange County Water District and currently partnering with the City of Dayton on the largest dedicated PFAS facility in the U.S. Director of Engineering Sochi Watt presented a timeline that targets the completion of a desktop study by February 9, 2026, followed immediately by bench scale testing starting February 10. The project schedule anticipates the completion of pilot testing by August 21, 2026, with a final Preliminary Design Report (PDR) expected by September 2, 2026. Watt noted that the consultants have been instructed to evaluate "novel approaches" alongside established technologies due to the rapidly evolving nature of PFAS treatment. The scope includes conducting six rapid small-scale column tests to narrow down media options efficiently. "This just kind of removes three to four months from that whole big picture of the pilot test," Watt told the board, emphasizing the need for efficiency to meet the regulatory window. The infrastructure push coincides with the release of the Authority’s 2025 Customer Focus Groups and Survey findings, presented by John Nienstead of Competitive Edge. The survey data highlighted a correlation between water quality perceptions and institutional trust. The agency’s satisfaction GPA dipped to 2.96, down from 3.17 in 2021, a shift Nienstead attributed largely to customers who distrust water quality information or dislike the taste of the tap water. According to the survey, PFAS treatment was the most requested capital project among ratepayers, with 37% identifying it as their top priority, outpolling reservoir capacity restoration and clearwell rehabilitation. "If you undertake a PFAS type of program, is you're addressing the concerns of the people who are giving you the C's, the D's, and the F's," Nienstead advised the board. The urgency of the project is underscored by recent monitoring data. Justin, the Director of Water Quality, confirmed that PFOA and PFOS levels have been detected above the upcoming 2029 federal Maximum Contaminant Levels. Public notifications regarding exceedances were issued in December 2024 and December 2025. Board discussion also linked the survey feedback on "bad taste" and "algae bloom" smells to the specific dynamics of the Sweetwater Reservoir. Director Cox noted that negative quality assessments were concentrated in the Bonita area, which is served by the reservoir where algae blooms impact taste and odor—issues the Authority hopes to resolve with future aeration and destratification projects. Staff confirmed that monthly updates on the PFAS pilot progress will be provided to the board as the agency moves toward the September 2026 design milestone.