Lewis River

PacifiCorp’s 510 megawatt (MW) capacity Lewis River hydroelectric facilities are located in rural southwestern Washington. The first dam site, Merwin, is approximately 10 miles east of Woodland, about 40 miles northeast of Portland, Ore. Constructed between 1931 and 1958, the Lewis River projects are located in a scenic area near Mount St. Helens in the Cascade mountain range.

PacifiCorp operates several recreational facilities associated with the Lewis River projects. These facilities include 318 camping sites, 268 picnic sites, several boat ramps, swimming beaches, fishing access, and day use areas.

More information about the Lewis River Project

Relicensing documents

See license applications and supporting technical documents for the Lewis River hydroelectric projects – Merwin, Swift and Yale. 

Fish passage projects

Construction work began in April 2011 on new fish passage facilities at the Lewis River project. The new facilities collect adult fish at Merwin Dam and transport them upstream of Swift Dam where they are released to move up the river to spawn. 

Aquatic fund applications, annual reports and close-out reports

PacifiCorp and Cowlitz PUD are soliciting 2023/2024 proposals as of July 28, 2023 for Resource Project funding, Bull Trout projects and design-only projects to benefit fish recovery throughout the North Fork Lewis River, with priority given to federal ESA-listed species.

License implementation

ACC / TCC documents, meetings & reports

Review documents and reports for the Aquatics Coordination Committee (ACC) and the Terrestrial Coordination Committee (TCC) for Lewis River.

Aquatic Technical Subgroup (ATS)

See information for the Aquatic Technical Subgroup, including aquatic monitoring and evaluation, and hatchery operating plans. 

Wildlife, recreation & shoreline management

Review wildlife habitat management plans, Recreation Advisory Committee documents and Shoreline Management Plans. 

Project contact

Todd Olson
Director, Compliance
825 NE Multnomah Street, Suite 1800
Portland, OR 97232
(503) 813-6657