‘Cooking the Fish’: Irrigators and Environmentalists Disagree Over Reducing Eel River’s Flow at Scott Dam

The public comment period for a proposed reduction in the diversion of water from the Eel River into the East Branch of the Russian River is now closed. PG&E, which still owns and operates the Potter Valley Project, has asked regulators for permission to reduce the flow into the East Branch from 75 cubic feet per second (cfs) to 25. The utility is also asking for the flexibility to cut the flow to five cfs if the water temperature at a gage near Scott Dam exceeds 16 degrees Celsius. That’s about 60 degrees Fahrenheit, which creates dangerous conditions for juvenile salmon. Last year, only 145 adult steelhead were counted at a fisheries station at Cape Horn Dam, downstream of Scott Dam.

Scott Greacen is the Conservation Director for Friends of the Eel River, which has long fought for the full removal of the Potter Valley Project. On August 1first, he reported, “The water coming out of the needle valve right now is 17.44 degrees Celsius. That is already approaching the point where pikeminnow, not native to the Eel, but introduced via the Lake Pillsbury reservoir, begin to out-compete juvenile steelhead. And as water temperatures continue to rise into the 19, 20, 21 degree range, you’ll eventually see mortality of all the juvenile steelhead.”

Water is released from Lake Pillsbury into a stretch of the Eel River from a needle valve at the bottom of Scott Dam, which impounds the reservoir. From there, it makes its way to a diversion tunnel that directs the water to Potter Valley and the Russian River. Due to seismic concerns, the Division of Dam Safety has instructed PG&E to leave a set of gates on top of the dam open all year round, lowering the level of the lake. Initial engineering analysis has indicated that the dam is more susceptible to earthquake damage than was previously known. Lowering the lake level is a precautionary safety measure.

But no one is satisfied with PG&E’s proposal. Environmental advocates and fishermen are raising the alarm about high water temperatures and low fish numbers, while irrigators are frustrated about getting drought-year quantities of water following such a wet winter. “We’re suddenly dealing with an issue that isn’t due to naturally occurring conditions,” said Janet Pauli, chair of the Mendocino County Inland Water and Power Commission and a director of the Potter Valley Irrigation District. She’s dismayed that Russian River water users may have to ration water like they did in 2020 and 2021. But this year, the lake is down due to the new seismic policy, not lack of water. “So it’s very similar to what would happen under natural conditions, if the lake never filled up in the winter time. If it just got to a certain height and that’s as far as it got,” she explained.

There’s no word on when the temporary variance would be implemented. The project license requires that flows to the East Branch be reduced to 35 cfs by mid-September. Potter Valley would still be allowed its contract amount of 50 cfs, though Pauli says that in drought years, the district has agreed to limit its water use.

“I think we’re all practical enough to know that if you normally have a bucket of water, and that’s what you get to use, you deal with it,” she said. “If you have half a bucket of water, you deal with it. You lose crop. You lose income. You lose quality of the crop you have left. But at least you can somehow try to manage under really extreme and unusual circumstances like the drought of 2021. This year, we’re not in that situation at all.”

PG&E has also filed a plan for a long-term flow regime, which, if approved, would go into effect next year and remain in place until decommissioning. Under that plan, flows into the East Branch would be between five and 25 cfs, which PG&E predicts would result in “a reduction of habitat for rainbow trout and other aquatic species” in the Russian River.

Greacen says the wild fish in the Eel should take precedence over the hatchery fish in the Russian, which are easily replaced by planting. “The problem is, we are pumping water down the East Branch Russian River right now that isn’t needed in the East Branch Russian River,” he contends. “Its original purpose was to support a rainbow trout fishery in the East Branch that’s fish planted by the Department of Fish and Wildlife for a recreational fishery. That’s nice. But the value of that fishery compared to the remaining few thousand wild steelhead in the Upper Eel is completely insignificant.”

PG&E has asked for variances in the flow regime for 7 out of the last ten years, when it was able to raise the gates on top of Scott Dam. It told the Federal Energy Regulatory Commission that, “The need for flow variances demonstrates that current license-prescribed flows will be unobtainable in nearly all years with the gates permanently inoperable and the reservoir storage restriction in place.”

But Pauli says that, as of right now, there is plenty of water in Lake Pillsbury to support the minimum instream flows of 75 cfs into the Russian River. As for reducing the flows, “It’s not warranted at this time,” she declared. “There should be a mechanism that allows PG&E to, based on discussions with what’s called the Drought Working Group, which are agencies and stakeholders on both sides, that we should be able to adjust these flows based on what the current conditions really are…We are calling it an arbitrary decision to immediately to go to a dry year classification, which reduces our flows significantly.”

But Greacen is chagrined that FERC has still not taken action on the request to cut back on the diversion. He warns that, “There’s a real risk that by the time FERC actually decides whether to approve this plan, it’ll be too late for it to have any effect, and we will have in essence cooked many of the fish.”