Water delivery cuts hurt farmers, fail to benefit fish

AgAlert, California Farm Bureau Federation, by Siskiyou County Farm Bureau President Ryan Walker November 30, 2022

The year 2022 has been one that few growers in Siskiyou County want to repeat. Following Gov. Gavin Newsom’s drought emergency order, the California Water Resources Control Board imposed emergency regulations to establish minimum flows in the Shasta and Scott rivers. Historic curtailments in water deliveries cost farmers millions of dollars of lost production.

As the year comes an end, it is worth considering what environmental benefit was achieved for such a substantial cost to agriculture. Unfortunately, now that flow and water data from the season is complete, it is very clear that denying farmers irrigation supplies provided no meaningful environmental benefit for threatened coho salmon and other fish.

Snowpack is the primary source of water in the Scott River, while springs drive the Shasta River system. The one great takeaway on the Scott River is that mandates can’t make water. How the Scott River operates during a particular year is almost entirely a function of the amount of water stored in the form of snow in the mountains surrounding Scott Valley.

When minimum flows were first discussed for the Scott River, water users noted that demand for water by agriculture had little to do with river function. Except for the wettest years, the undammed river disconnects and goes subterranean in certain stretches every summer once snowpack is depleted. Uninterrupted river flows and accessibility of spawning areas happens only once our overgrown forest goes dormant and we receive a heavy fall rain. Massive water curtailments for agriculture had no effect on this pattern.

Still, the water board by July 14 completely curtailed all surface-water diversions and groundwater pumping. The only farmers permitted to irrigate in Scott Valley were groundwater users who had entered into voluntary agreements before the irrigation season to reduce annual pumping by 30%. Nonetheless, the river level dropped.

As of mid-November, well after the end of the irrigation season, the Scott River flow was only a small fraction of the required minimum. This wasn’t due to water diversions for irrigation or to pumping by farmers, which had ceased months earlier. In the end, what the water board succeeded in proving—through sweeping curtailments—was that water flow in the Scott had little to do with agricultural water demand. The state should consider the facts and build water storage facilities to mitigate impacts of reduced snowpack in dry years. Officials should also promote groundwater recharge and watershed management that helps fish in the Scott River—without imperiling our agricultural economy.

The story in the Shasta River watershed is very different from the Scott but equally frustrating. Springs within the system act to stabilize water flow through the year. When agricultural water use was curtailed, river flows did increase. Because the State Water Board minimum flows were set so high, the flows in the Shasta were substantially higher than average despite the three-year drought. While the river flowed at elevated levels, agricultural water users watched their fields and stock-water ponds dry to dust. The environmental benefits of all this water flowing past dry or fallowed fields proved to be minimal at best.

The stated purpose for maintaining minimum flows in the Shasta was to safeguard cool water temperatures and sufficient dissolved oxygen levels for over-summering coho salmon. For many years, the Shasta Valley Resource Conservation District has maintained flow and water quality records along the Shasta River. Its data show that curtailments had virtually no effect on annual average river temperature or dissolved oxygen.

A very telling experiment happened late in August when Shasta River Water Association, frustrated at not receiving a response to their request for emergency livestock water, violated the state’s curtailment order and turned on diversion pumps. The river flow downstream dropped from mandated levels of 50 cubic feet per second to less than 20 CFS for about a week. This dramatic flow drop had no effect on average daily water temperature or dissolved oxygen, according to Shasta Valley RCD data. In short, increased flows do not necessarily help fish. In fact, it is possible that mandated high flows actually hurt over-summering habitat by diluting the value of cold-water springs along the river.

Farmers know expensive lessons are often the best learned. Hopefully, the state will learn that minimum flows are poor tools. Many things can be done to help fish populations. But one-size-fit-all mandates from policymakers in Sacramento are destined to fail.

We need solutions driven by local stakeholders who can consider the unique function and resources of each watershed. There are indeed solutions that can do far better for farms and fish.

Permission for use is granted. However, credit must be made to the California Farm Bureau Federation

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