Scott Dam that controls the flow coming out of Lake Pillsbury, a piece of infrastructure slated to be removed [Picture from the Mendocino County Farm Bureau]
The Department of Reclamation has put $2 million towards the next phase of designing a facility to continue diverting water from the Eel River into the Russian after PG&E removes the Potter Valley hydropower project dams.
Congressman Jared Huffman made the announcement at the south boat ramp of the Coyote Valley Dam at Lake Mendocino on Friday, along with representatives from state and federal agencies, the Round Valley Indian Tribes, and conservation groups. He told the assembled dignitaries that, “I drafted language in Congress to create this new program for the Bureau, the Aquatic Ecosystem Restoration Program, very much with that kind of win-win water solution in mind — In fact, with this project in mind.”
The Aquatic Ecosystem Restoration Program is part of Biden’s Bipartisan Infrastructure Law. The check is made out to Sonoma Water, so the Eel Russian Project Authority, a group of governmental agencies and conservation groups, can bring the design of the diversion facility to 60%. Sonoma Water, which is part of the Authority, used a grant from the state Department of Water Resources to design the facility to its current 30%. The Authority is planning to build a set of pumps on the Eel River in Potter Valley, just above where Cape Horn Dam is now. If all goes according to plan, these will divert water through the tunnel between the watersheds seasonally, during high flows.
Huffman and Bureau of Reclamation Commissioner Camille Calimlin Touton indicated that future funding for the full design and construction of the facility is not entirely unlikely.
“I suspect at least in part they’re going to be looking at me to bring some money home,” Huffman told a friendly crowd. “That’s part of what I do.” He added that he suspects the Bureau’s “commitment to the design phase of this project signals a significant federal interest in seeing this project through, and I think this gives us an opportunity to explore construction funding when we get to that phase as well.”
“This was the first iteration of Aquatic Ecosystem Restoration Program funding,” Touton said. “It’s brand new. We have $250 million as part of the Bipartisan Infrastructure Law. I anticipate that as we move forward, there will be other funding announcements.”
PG&E, which owns and operates the Potter Valley Project, said last week that it needs an extra six months to file its final surrender application and decommissioning plan, nudging the date to next summer. Janet Walther, Senior Manager of hydropower licensing with PG&E, says she doesn’t expect it to delay the removal.
She thinks that, once the Federal Energy Regulatory Commission, or FERC, grants the utility approval to remove the infrastructure, it would take a year to remove Scott Dam. “But we do not really have those details yet,” she acknowledged. “We have not yet finalized our work with our resource agencies to really determine the logistics and how that works. And the least impacts to the fisheries.”
Grant Davis, General Manager of Sonoma Water, spoke in the van on the way from Lake Mendocino to Cape Horn in Potter Valley. The roads to the dam were dotted with large signs beseeching viewers to save Lake Pillsbury, the reservoir impounded by Scott Dam. Davis anticipates that Sonoma County water users will have to pay a surcharge to keep the facility going, once it is in place and everyone knows how well it works and how much water it makes available. “I think the folks that are actually getting the water would be the ones that would be providing that level of funding,” he predicted. He thought the presence of Touton, from the Bureau of Reclamation, and Chuck Bonham, the Director of California Department of Fish and Wildlife, indicated that, “This is an exciting project. One that would certainly compete very well for federal and state dollars. And those dollars would be identified hopefully to help construct the facility.”
Don Seymour, Deputy Director of engineering with Sonoma Water, gave some details about water supply, which the agency has studied with modeling. “Without any interventions, such as curtailing water rights or reducing minimum flows lower than they’re supposed to be,” he qualified; “Lake Mendocino could go dry one to two times out of 10 years, on average….there could be interventions that could prevent that, but you are risking the water supply for 100,000 plus people that are above Dry Creek. So this is a big deal.”
And he said that a system called Forecast Informed Reservoir Operations, or FIRO (essentially using precise weather predictions with lots of data points to determine when it’s safe to release or retain water) is keeping tens of thousands of acre feet in the reservoirs. Since 2021, a pilot program has allowed the Army Corps of Engineers, which owns and operates Lake Mendocino, to retain 11,000 acre feet that would have otherwise been released for flood control. In Lake Sonoma, there is another project underway that’s retaining an additional 19,000 acre feet.
“That’s like another small reservoir,” he said. “That’s not through building any infrastructure. That’s completely through just re-operation and using advanced forecasting techniques that are becoming available.”
Josh Fuller, a scientist with the National Oceanic and Atmospheric Administration, thinks the new facility will have benefits to salmon, by opening up prime habitat above Scott Dam. “NOAA Fisheries has done quite a bit of research above Scott Dam, and the habitat available up there,” he said. “We know that there are probably 100 miles for Chinook salmon and 200 miles for steelhead trout. A lot of high-value habitat, perennial streams, high-gradient streams where steelhead in particular can out-compete invasive pikeminnow. That’s a big concern in the river.”
Fuller and Bonham both anticipate that PG&E’s delay in filing its decommissioning application will prevent a longer delay later. There is currently a CDFW fish-counting station at Cape Horn Dam, and Bonham intends to continue “to have a monitoring program that’s overlaid with the restoration, so we can track success over time.”
Lake County, which has long argued for the preservation of Lake Pillsbury, did not send representatives to Lake Mendocino. Huffman placed the decision to remove the dams squarely on the shoulders of the Potter Valley Project’s owners. “I have, as you know, long supported the two-basin solution, which does embrace removal of Scott Dam,” he noted; “and that probably doesn’t make me the most popular guy in Lake County…But it’s PG&E’s dam, and they’re removing it.”
