Hydroelectric power is a clean, renewable resource that generates electricity without burning fossil fuels or polluting the air.
Our hydroelectric projects generate about three billion kilowatt hours of electricity each year, enough to serve about half of our customers’ power needs.
Our Hydroelectric Projects
Our projects are licensed through the Federal Energy Regulatory Commission.
- The Cowlitz River Project includes Mayfield Dam completed in 1963 and Mossyrock Dam completed in 1968.
- The Nisqually River Project includes Alder Dam and LaGrande Dam, built in 1945, and the original LaGrande powerhouse, built in 1912. This project produces certified green power.
- The Cushman Hydro Project, located on the North Fork of the Skokomish River, has two dams: Cushman No. 1 built in 1925 and Cushman No. 2 built in 1930.
- The Wynoochee River Project has a powerhouse built by Tacoma Power in 1993 at a flood control dam built by the U.S. Army Corps of Engineers in 1972.
Education & Tours
Tacoma Power has an active energy education program. It helps support the Foundation for Water and Energy Education, a great source for basic information about hydro power.
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 make arrangements for a tour, please complete the form below.
Tours are available at all four of Tacoma’s hydro facilities:
In order for our staff to properly prepare, please request your tour at least one month in advance of your desired tour date. We recommend that groups do not exceed 50 people. If you have a special circumstance, please make a note in the “additional information” field below.
Tacoma Power is an active member in the communities where our projects are located.
Tacoma Power maintains a role in the communities through participation in the local chambers of commerce, the White Pass Scenic Byway, the Nisqually River Council, the Lower Columbia Fish Enhancement Group, the Lower Columbia Fish Recovery Board and Forterra.
Our staff members show strong support for their local communities by supporting United Way and assisting many local organizations and schools.