Today, the State Water Resources Control Board is releasing its long awaited analysis of proposed changes to instream flows in the Stanislaus, Tuolumne, and Merced rivers. As the Board recognizes, these rivers are critically impaired by unsustainable water diversions that have harmed native salmon, fishing jobs, and the health of the Bay-Delta estuary.
This morning the Board released a summary of its proposal, which recommends that 40% of the unimpaired flow remain instream during the February to June period, within an adaptive management range of 30-50% of the unimpaired flow (for more background on this proceeding and what “unimpaired flow” means, see this fact sheet). The full analysis will be available later this afternoon. In the coming weeks, we will be digging into the details with several of our colleagues, and preparing comments on both the scientific basis for this flow proposal and potential means to reduce water supply impacts of balancing instream flows with water use for farms and cities. Below are some initial reactions:
The Board’s proposal of 40% of the unimpaired flow as a starting point falls short of what scientists, state and federal agencies, and conservation and fishing groups have concluded is necessary to restore and sustain salmon and the health of these rivers. For instance, in 2013 the California Department of Fish and Wildlife concluded that 50-60% of the unimpaired flow must remain instream to protect salmon. While habitat restoration and other measures must complement improvements in flow, the available science indicates that flows higher than 40% are necessary in conjunction with such measures. We will be carefully reviewing the scientific basis for the Board’s conclusion that these flows are likely achieve the objective of increasing salmon populations (the so called “Salmon doubling goal” required by the water quality control plan and state and federal law).
That said, the Board’s proposal does increase flows compared to the status quo, particularly on the Tuolumne and Merced rivers. It’s not dramatically different from the status quo on the Stanislaus River, where the Board has previously estimated that median unimpaired flows were 40%.
On the water supply side, the Board’s summary estimates that the proposal will have virtually no water supply impacts in nearly 50% of years (wet and above normal years). The vast majority of water supply impacts occur in critically dry years, when water is short for everyone. But, given the Board’s repeated and multiple waivers of water quality standards during the current drought, it’s highly questionable whether these protections would ever be implemented and these water supply impacts realized.
The Board estimates that the proposal would reduce agricultural revenues by 2.5% on average, before water users implement any mitigation measures to reduce such impacts. There are clearly opportunities to reduce such impacts through improved agricultural water use efficiency, canal lining, groundwater storage projects, and the like.
Similarly, the proposal likely will reduce surface water supplies for San Francisco and communities in the Bay Area that use water from the Tuolumne River. The drought has shown that these communities can substantially reduce water use without harming the economy, and investments in water recycling, improved efficiency, stormwater capture, and other tools can help ensure a healthy economy and environment.
Ultimately, while the Board’s proposal is a step in the right direction, it falls short of what the science shows is needed to protect and restore the health of these rivers and their native salmon, the health of the Bay-Delta estuary, and the thousands of fishing jobs that depend on healthy salmon runs. Depriving these rivers of the flows that the science says is necessary to keep them healthy is not a “balanced” approach – it is simply a continuing failure to grapple with our over-allocated system. A better approach would be to provide the flows that the science supports, and invest in the alternative water supply measures that are abundant and untapped. If you care about salmon or the Delta, now is the time to speak up in favor of improving flows in the Lower San Joaquin River and its tributaries.