Potter Valley Project

Client: U.S. Department of Interior (DOI); Round Valley Indian Tribes of the Round Valley Indian Reservation, California
Project: Potter Valley Hydropower Project (FERC No. P-77)

The Potter Valley Project (PVP), FERC Project No. P-77, is located in Mendocino County, California near the community of Potter Valley. The PVP diverts flows from the Eel River to the Russian River via a water diversion and tunnel at Cape Horn Dam (Van Arsdale Reservoir) on the Eel River. The PVP became operational in 1908 and, since 1930, has been owned and operated by the Pacific Gas and Electric Company (PG&E).   The project was relicensed in 1983 after a protracted and contentious legal battle between PG&E and many other federal, state, and local entities, including the Round Valley Indian Tribes (RVIT). The principle matter of conflict was reduced instream flows in the Eel River.

Beginning in 1998, NRCE staff has aided the U.S. Department of Interior (DOI) in developing instream flow requirements on behalf of the RVIT and other entities. NRCE reviewed and commented on numerous FERC filings by various interested parties (PG&E, RVIT, and others) as well as on Draft and Final Environmental Impact Statements prepared by the FERC and consultants in determining Eel River instream flow requirements. NRCE also prepared the minimum flow proposal for the PVP endorsed by the RVIT, which was eventually accepted by FERC. In doing so, NRCE developed hydrologic models of the Eel and Russian River Basins which have generally been adopted for use in FERC proceedings and proposals. Furthermore, NRCE – in cooperation with the Tribe and DOI – composed a preliminary federally reserved water rights claim for three sources of water: irrigation water requirements based upon practically irrigable acreage; non-agricultural water requirements based on domestic commercial, municipal, and industrial uses; and water requirements for fisheries.