Board approves MOU to advance diversion agreement tied to Potter Valley dam decommissioning

The Humboldt County Board of Supervisors voted to approve a memorandum of understanding on Feb. 11 to advance a water-diversion agreement tied to Pacific Gas & Electric Co.’s planned decommissioning of the Potter Valley hydroelectric project on the Upper Eel River. The board approved staff’s recommendation by vote, and the MOU will guide a more detailed agreement due to the parties for review in July.

Why it matters: The Potter Valley project currently diverts water from the Eel to the Russian River; the MOU proposes a new intake and rules for seasonal diversions while also advancing dam removal on the Eel. Supporters said the framework protects fisheries, restores water-right ownership to a tribal entity based in the Eel watershed, and will generate a predictable restoration fund. Opponents warned the MOU leaves potential for future diversion unless terms are strictly enforced.

The MOU’s key terms and mechanics - Water-rights transfer and lease: The draft MOU calls for PG&E’s appropriative water rights used for the project to be transferred to the Round Valley Indian Tribes and then leased back to a joint‑powers entity that would construct and operate a new diversion facility. The Round Valley Indian Tribes would therefore hold the water-right title while leasing diversion use to the Russian‑Eel authority. - Governance and implementing entity: The Eel–Russian Project Authority, formed as a joint powers authority that includes Sonoma Water, the Mendocino Inland Water and Power Commission and Round Valley Indian Tribes, would be the likely owner/operator of the new diversion infrastructure and the entity that applies to the Federal Energy Regulatory Commission (FERC) for any use of PG&E lands and facilities. - Facility design and capacity: The MOU describes a run‑of‑river style intake at the former Cape Horn/Cape Horn Dam area, with conveyance to the existing tunnel; engineering shown in public materials assumes the diverted flow could be conveyed at up to roughly 300 cubic feet per second (cfs). The design would remove the former dam elements and leave a low-profile control structure in the channel rather than a storage…