Cowlitz River Project

Built in the 1960s, the Cowlitz River Project is Tacoma Power’s largest hydropower facility. It produces enough clean, reliable hydropower each year to serve more than 150,000 homes.

To balance our need for electricity with our responsibility for preserving wildlife and fish habitat, the project includes the Cowlitz Salmon Hatchery and the Cowlitz Trout Hatchery. We own both facilities and the Washington Department of Fish and Wildlife operates them with our funding and support.

To help juvenile and adult fish get safely around Mossyrock Dam and Mayfield Dam, we use a trap-and-haul process at our hatcheries. This includes collecting coho salmon, Chinook salmon, steelhead and cutthroat trout and then transporting them by truck to sites on the Tilton, Cowlitz and Cispus rivers to continue their spawning journey.

We also stock Riffe Lake, Mayfield Lake and Swofford Pond with a variety of fish to enhance recreation and angling opportunities in the area.

In addition, we help protect more than 14,000 acres within the Cowlitz Wildlife Area, a mix of emergent wetland, riparian forested wetland, coniferous forest and mixed deciduous forest. Learn more about our fish and wildlife programs in the area.

The Cowlitz River Project also supports a wealth of outdoor public recreation such as nature watching, hiking, boating, swimming, fishing, hunting, mountain biking and horseback riding. Part of the area is included in the Great Washington Birding Trail.

To get the latest information on river flows, lake levels and boat launch usability, visit MyTPU.org/LakeLevels.

For more information about our programs, contact us at cowlitz@cityoftacoma.org.

Free group tours of Tacoma Power’s hydroelectric facilities are available by appointment to school, civic, business and recreational groups during regular working hours. To learn more about our tour program and to request a tour, please visit our main tour page.