Pacific Gas and Electric Company's Potter Valley Hydroelectric Project Delivers on Spring Frost Protection and Late Fall Irrigation Needs

Strategic Insights -

The Pacific Gas and Electric Company (PG&E) has submitted a report to the Federal Energy Regulatory Commission (FERC) detailing the implementation of the Potter Valley Hydroelectric Project's (Project) Article 52 amendment. This amendment allows the Project to provide additional flows to the Potter Valley Irrigation District (PVID) for commercial crop frost protection and late fall irrigation. As per the FERC order, PG&E was required to annually file reports on the status of agency requests for early spring warm water spill flow releases and the sum of all PVID requested contract delivery rates.

Key Takeaways:

  • The Potter Valley Hydroelectric Project has successfully implemented the Article 52 amendment to provide additional flows to the Potter Valley Irrigation District (PVID) for commercial crop frost protection between March 15 and April 14 and for late fall irrigation between October 16 and October 31.
  • The report highlights the Project's compliance with FERC's order to annually file a listing of agency requests for early spring warm water spill flow releases and the status of how the project operated to address these requests while maintaining license compliance.
  • The Project released warm water from the reservoir from April 23, 2025, through May 12, 2025, in response to a B3 water management request by the National Marine Fisheries Service, U.S. Fish and Wildlife, California Department of Fish and Wildlife, and Round Valley Indian Tribes.
  • The intent was to release 300 cfs of warm water, and supplement flow from the needle valve as needed to maintain downstream compliance flows.
  • Table 1 displays the total possible volume of water that could be diverted from the Eel River to the East Branch Russian River during each specific period, with the volume of water available for possible delivery to PVID totaling 24,232 acre-foot (AF) for the 2024/2025 diversion year, but PVID is not allowed to exceed actual water deliveries of 19,000 acre feet by contract with PG&E.
  • The actual water delivered during the 2024/2025 diversion year was 5,403 acre feet, with water deliveries requested by PVID at E5 & E6 totaling 5,824 AF.

Statistics:

  • 300 cfs: the intended rate of warm water release from the reservoir.
  • 64 cfs: the needle valve flows reduced to on April 30, 2025.
  • 5/5/2025: the date when needle valve flows were increased to approximately 300 cfs to supplement declining natural inflow into the reservoir.
  • 24,232 AF: the total possible volume of water available for possible delivery to PVID for the 2024/2025 diversion year.
  • 19,000 AF: the maximum allowed water deliveries to PVID by contract with PG&E.
  • 5,403 AF: the actual water delivered during the 2024/2025 diversion year.

Sources:

  • Pacific Gas and Electric Company, "Article 52, 2017 Late Fall Irrigation and Spring Frost Protection Report", submitted to the Federal Energy Regulatory Commission (FERC) on June 25, 2025.