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Potter Valley Hydroelectric ProjectFERC Project No. 77

Overview & History

Stakeholder MeetingMarch 9, 2017

Paul KubicekPG&E, Senior Consulting Scientist

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Potter Valley Project

• 9.4-MW hydroelectric project

• Sufficient to power ~6,900 homes

• Inter-basin diversion of water from upper mainstem Eel River to upper Russian River (East Branch)

• Initial construction completed in 1908

• Operated under FERC license #77

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Eel River above Lake Pillsbury - Spring

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Eel River above Lake Pillsbury - Fall

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Lake Pillsbury

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Scott Dam / Lake Pillsbury

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Eel River below Lake Pillsbury

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Cape Horn Dam / Van Arsdale Reservoir

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Eel River below Cape Horn Dam

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Eel River above Outlet Creek

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Van Arsdale Reservoir & Intake

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Penstock

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Penstock

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Potter Valley Powerhouse

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Potter Valley Powerhouse Tailrace

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PVID East Canal & East Branch Russian River

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Lake Mendocino

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Potter Valley Project History

• Cape Horn Dam, diversion, & powerhouse (1905-08) -Eel Power & Irrigation Co. / Snow Mt. Water & Power Co. (1906)

• Scott Dam (1920-21) / 10-ft high increase (1925)

• Water for irrigation (1924)

• PVID irrigation contract (1926)

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Potter Valley Project History

• PG&E acquired project (1930)

• Generating unit upgrades (1930s-50s)

• Tunnel intake reconstructed (1971-72)

• Powerhouse bypass (2009-10)

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Cape Horn Dam

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Cape Horn Dam

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Penstock Under Construction

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Powerhouse Generator in Transit

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Potter Valley Powerhouse ~1910

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Scott Dam Looking Upstream

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Scott Dam

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Scott Dam without Gates

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Cape Horn Dam Fish Ladder

• Concrete pool & weir ladder constructed “shortly after” Cape Horn Dam

• Van Arsdale Fisheries Station (CDFW)– Egg taking station, as early as 1915

– First fish counts began 1922/23

• Major improvements (1987)– Increased attraction flow

– Realigned ladder entrance

– Modified pools in ladder

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Cape Horn Dam Fish Ladder - Original

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Cape Horn Dam Fish Ladder – Current

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Van Arsdale Fisheries Station

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Van Arsdale Fisheries Station

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Van Arsdale Fish Screen

• Horizontal travelling screen (built 1971-72)

• Twin inclined plane screens (built 1994-95)– Compressed air sparger system

– Archimedes screw pump

– Fish bypass

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Van Arsdale Fish Screen - Original

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Van Arsdale Fish Screen - Current

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FERC Relicensing (1922-83)

• FPC 50-year license (1922)

• Protracted relicensing process (1970-83)

– Study Agreement (1979) to evaluate flows

– 3-Year Fisheries Study (1979-82)

– Settlement Agreement (1982)

• New FERC License (1983)

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FERC Relicensing 1983 to Present

• 10-Year Fisheries Study (1985-96)

• ESA listing for Chinook salmon & steelhead (1999, 2000)

• NMFS Biological Opinion – RPA (2002)

• Amended FERC license (2004)

– Balancing of water needs

– Annual monitoring ongoing

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Amended FERC License: Balancing of Water Needs

• Power production

• Eel River fisheries protection

• Russian River– Irrigation (PVID & SCWA)

– Fisheries protection

• Recreation– Lake Pillsbury storage

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Current Project Operations

• 2004 – April 14, 2022– Per requirements of NMFS RPA & Amended FERC

License

• Beyond April 14, 2022– Requirements to be determined through FERC relicensing

process

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Questions?