Board hears Scott and Shasta flow update; staff to draft scientific basis reports and economic analysis under AB 263 timeline

The State Water Resources Control Board received an extended briefing on November 4 about flow implementation, monitoring and long‑term planning for the Scott and Shasta River watersheds.

Board staff framed the discussion as a two‑track effort: continuing implementation of the existing drought emergency flow requirements while preparing long‑term analysis to support future decisions. Dan Schultz and other Division of Water Rights staff said consultants are drafting scientific basis reports that will analyze fish benefits across a range of potential baseline minimum flows; those drafts will be released for public comment prior to peer review. An economic analysis is being prepared in parallel to estimate costs and benefits of implementing long‑term baseline flows and will include an agricultural production model under development in the Office of Research, Planning and Performance (ORPP).

AB 263: schedule and implementation flexibility Staff described AB 263, recently enacted by the Legislature and effective Jan. 1, which extends the current emergency regulation through Jan. 1, 2031 or until permanent rules are adopted, whichever comes first. AB 263 preserves the existing implementation flexibilities in the emergency regulation (conditional curtailments, groundwater Local Cooperative Solutions, Watermaster coordination and other voluntary mechanisms) while requiring the board to provide annual public updates on progress toward permanent rules.

Key monitoring and implementation observations - Scott River: staff reported the Scott Valley experienced improved groundwater levels from 2020–2025; flows met the emergency minimums this irrigation season despite a relatively low early snowpack. Groundwater Local Cooperative Solutions received 35 applicants covering 11,293 acres (~63% of groundwater‑irrigated acreage), and about 96 meters are installed or scheduled. - Shasta River: staff summarized Applied River Sciences’ summer 2025 field study (pool temperatures, DO, macroinvertebrates) and described a short CDFW‑coordinated test of an alternative August flow regime in the Shasta (targeting 40–60 cfs around a nominal 50 cfs minimum). Storms and visibility limited survey work and coordination challenges were noted.

CDFW fisheries update California Department of Fish and Wildlife staff reported preliminary counts for the returning brood year that reared and outmigrated during the regulation period. CDFW staff said about 2,757 Chinook salmon have passed through the Scott counting station to date (below the 1978–2023 mean of ~4,758) and about 5,823 Chinook have passed the Shasta counting station (near longer‑term averages). CDFW observed juvenile salmonids and other fishes in both watersheds during summer baseflow snorkel surveys and described increased observations in reaches that remained wetted under the emergency flows. CDFW emphasized that the current baseline flows were intended to “avoid the extinction vortex” and to minimize population collapse while longer‑term analyses are completed.

Public comment and stakeholder input Tribes, NGOs, commercial fishing representatives and other stakeholders urged that staff tie flow options to specific biological outcomes (for example, smolts per spawner or recovery targets) rather than only flow volumes, request additional compliance points (gauges) beyond a single downstream compliance location, and incorporate water‑year‑specific flows or scaling that allows harvestable surplus and recovery scenarios in wet years. Stakeholders also urged clear timelines to complete scientific and economic work and recommended the board direct staff to pursue permanent rules within the AB 263 timeframe.

Next steps Staff said draft scientific basis reports and draft modeling reports will be issued for public comment (the Shasta modeling work is further along). The ORPP agriculture production model will be completed and used in the economic analysis; staff plans to solicit input from tribes, fishing industry representatives and agricultural communities as drafts are developed. Staff summarized that the scientific basis reports, economic analysis and updated modeling are intended to be used to inform potential future options: permanent flow regulation, water‑quality control planning, or other local solutions.

No formal board action was taken; the item was informational and public comment‑heavy. Board members asked staff to return with proposed flow ranges for review in the near term and to keep the board informed of timelines so the board can decide whether and how to pursue permanent rules within the AB 263 period.

Quote: “The existing baseline minimum flows were intended to avoid the extinction vortex, minimize further collapse of our existing fish stocks,” CDFW staff said during their presentation.

Article note: this report consolidates staff presentations, CDFW monitoring updates, stakeholder testimony and the staff summary of next steps related to the Scott and Shasta flow work under the AB 263 framework.