Trinity River

Trinity Dam Aerial Photograph

Update on Trinity Dam Maintenance: No additional water releases are being made out of Trinity Reservoir. Click news release to learn more.

The Trinity River Division of the Central Valley Project is comprised of: the Trinity Dam, a large storage reservoir; Lewiston Dam, which controls the water released into Trinity River; and Clear Creek Tunnel, which transports water from Lewiston Dam into Whiskeytown Lake in the Sacramento River Basin.

Trinity Dam and Lake: Trinity Dam regulates flows and stores water for various uses. Completed in 1962, Trinity Dam is an earthfill structure that is 538 feet high with a crest length of 2,450 feet. The dam forms Trinity Lake, which has a storage capacity of 2,448,000 acre feet. The lake offers recreation facilities for camping, boating, water skiing, swimming, fishing and hunting.

Trinity Powerplant: Trinity Powerplant at Trinity Dam has two generators with a total capacity of 105,556 kilowatts.

Lewiston Dam and Lake: Lewiston Dam is about 8 miles downstream from Trinity Dam. The dam creates an afterbay to Trinity Powerplant and regulates releases into the Trinity River. Lewiston Dam is an earthfill structure that is 91 feet high and 754 feet long, forming a reservoir with a storage capacity of 14,660 acre feet. The trans-basin diversion begins at Lewiston Lake via Clear Creek Tunnel to Whiskeytown Lake.

Lewiston Powerplant: Lewiston Powerplant at Lewiston Dam has one generator with a capacity of 350 kilowatts.

Clear Creek Tunnel: Clear Creek Tunnel is 10.7 miles long and conveys up to 3,200 cubic feet per second from Lewiston Lake to Judge Francis Carr Powerhouse and Whiskeytown Lake. It is the conduit for the trans-basin diversion.

Judge Francis Carr Powerhouse: Judge Francis Carr Powerhouse, on Clear Creek, has two generators with a total capacity of 154,400 kilowatts.

Whiskeytown Dam and Lake: Located on Clear Creek, Whiskeytown Dam stores Clear Creek runoff and diverted Trinity River flows discharged from Judge Francis Carr Powerhouse. The dam is an earthfill structure that is 282 feet high with a crest length of 4,000 feet. Whiskeytown Lake has a capacity of 241,100 acre-feet and provides recreation facilities for picnicking, camping, swimming, boating, water skiing, fishing and hunting. The Spring Creek Tunnel diverts water from Whiskeytown Lake to the Spring Creek Powerhouse and Keswick Dam on the Sacramento River.

Trinity River Hatchery: The Trinity River Hatchery, operated by the California Department of Fish and Wildlife, has a production capacity of roughly 40 million salmonid eggs. It is located immediately downstream from Lewiston Dam and compensates for the upstream spawning area rendered inaccessible and unusable by the dams.


Trinity River Restoration Program:

Trinity River Restoration Program banner logo

Trinity River Restoration Project is a multi-agency program established by the Department of the Interior and is a collaboration of eight federal, state, county and tribal partners. The project implements Interior's Record of Decision of 2000, a decision document based on environmental analysis as well as public issues and concerns. It directs the agency to restore fisheries of the Trinity River impacted by dam construction and related diversions of the Trinity River Division of the Central Valley Project.

P.O. Box 1300
1313 South Main Street
Weaverville, CA 96093

Phone: 530-623-1800
Fax: 530-623-5944











Last Updated: 3/22/23