SFPUC warns 40% Bay‑Delta flow requirement could force steep rationing; environmental groups press for stronger flows

The Public Safety and Neighborhood Services Committee held a hearing on the State Water Resources Control Board’s proposed Bay‑Delta Water Quality Control Plan and heard a detailed presentation from the San Francisco Public Utilities Commission (SFPUC), followed by more than a dozen public speakers representing environmental groups, fisheries interests, residents and business groups.

SFPUC Assistant General Manager Stephen Ritchie told the committee the Tuolumne River and Hetch Hetchy system are central to the Bay Area’s supply: the Tuolumne supplies an estimated 85 percent of the San Francisco regional water system and the SFPUC serves roughly 2,600,000 customers across the Bay Area. Ritchie said the state board’s draft proposal to require about 40 percent of unimpaired flows on San Joaquin River tributaries during February through June — with possible variability between 30 and 50 percent mentioned in the draft — is significant because it would reduce water available for storage and increase the frequency and severity of dry‑year shortages.

“We think the state board’s proposal is very fuzzy, not very clear on exactly what it’s going to accomplish and how it’s going to accomplish it,” Ritchie told the committee, later saying implementation uncertainty raises litigation risk and could force the PUC to pursue large, costly supply projects (additional storage, purified‑water reuse or desalination) or pay premiums for transfers to protect service levels. In one analysis Ritchie described, the board’s proposal could increase the frequency of shortages from about one in 10 years to two or three in 10 years and could produce rationing in the range of 20–50 percent during extended drought scenarios depending on demand assumptions.

Ritchie and the SFPUC said they prefer negotiated settlements and "functional flows" — targeted, measurable flow actions combined with habitat restoration and other measures — rather than a single blunt percentage. The PUC emphasized planning for more severe droughts and said the agency has invested in long‑range planning and storage but warned the scale of supply projects required to offset a 40 percent unimpaired flow requirement would be large.

Environmental and fisheries groups strongly urged the committee to back the state board’s effort or go further. Speakers from the Sierra Club, Bay Institute, Baykeeper, Tuolumne River Trust and fishing associations described long‑term declines in salmon and other native species and argued that increased freshwater flows are a necessary element of ecosystem recovery. John Rosenfield of the Bay Institute said technical analyses in the Supplemental Environmental Document show flows below 50 percent are unlikely to produce temperatures and habitat sufficient for juvenile salmon in some tributaries: “flows less than 50% will not result in temperatures that are cold enough for salmon during the months that they need it,” he said.

Tuolumne River Trust’s Peter Dreikmeier acknowledged SFPUC’s storage capacity but argued that settlements and conservation should not be used as an excuse to delay stronger protections. He said the trust favors roughly 50 percent of unimpaired flow as a compromise to meet biological goals, and he urged the Bay Area to lead by supporting robust flow standards and not letting settlement talks be used to indefinitely postpone regulatory action.

Other public commenters raised a range of points: some urged the Board to act promptly because ecosystems are deteriorating; others urged preserving local water supplies and warned that deep rationing or costly infrastructure could harm housing production and economic plans. Adrian Covert of the Bay Area Council urged support for voluntary settlements to resolve implementation details, warning that the SED’s requirements — if implemented without alternatives — could force substantial investments or re‑examination of local general plans.

Committee members thanked presenters and public speakers and said they had more to deliberate. Supervisor Feuer moved to file the hearing; the motion was recorded and the committee filed the hearing without objection. The committee noted the matter will reach the full Board of Supervisors for further consideration.