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Nisqually River Project

Alder Dam is one of two Nisqually River dams

Tacoma Power began generating electricity from the water of the Nisqually River nearly 100 years ago. The original diversion dam, completed in 1912, was replaced in 1945 with Alder Dam and LaGrande Dam. The Nisqually River Project is Tacoma Power's second-largest hydroelectric resource, generating enough power to serve nearly 43,000 Northwest homes.

Alder Dam forms the 3,000-acre Alder Lake. It’s ideal for boating, fishing, swimming and camping. Tacoma Power provides several top-quality recreational facilities at Alder Lake.

As part of its responsibility for owning the Nisqually River Project, Tacoma Power provides fisheries and wildlife habitat programs while providing recreational opportunities. Kokanee planting, nesting boxes for wood ducks and bluebirds, and improving elk forage are just a few of the programs in and around Alder Lake and the surrounding 3,500 acres of wildlife land.

A second federal license for the Nisqually River Project was issued in 1997. The license was developed with the Nisqually Tribe, Nisqually River Council and agencies, including the Washington Department of Fish and Wildlife, U.S. Fish and Wildlife Service and the National Marine Fisheries Service.

Alder Lake offers beautiful views of Mt. Rainier

Alder Lake is the reservoir formed by Alder Dam. The beautiful lake, with striking views of Mt. Rainier, attracts more than 100,000 people yearly for boating, camping, fishing, swimming, picnicking and other outdoor fun.

Tacoma Power‘s federal license guides the priorities for managing the elevation of Alder Lake. The highest priority is maintaining downstream river flows at or above a specified minimum. When natural river flow is less than the required minimum - mostly during summer and early fall - additional water must be taken from Alder Lake to achieve the minimum downstream flow. The added flows improve rearing habitat for salmon and steelhead, and are greater than what would naturally occur without the dams.

The next highest priority is keeping the lake's elevation high during the prime recreation months.

Alder Lake is considered a small reservoir and is unable to provide downstream flood control. Even so, Tacoma Power lowers the elevation of the lake when possible during winter months to enable some capture of high water inflows from rainstorms and snow melt.

The 45-acre reservoir behind LaGrande Dam is not publicly accessible because of the steep, rugged terrain.


Take a Tour

Free group tours of the Nisqually River Project facilities are available by appointment to school, civic, business and recreational groups during regular working hours. To make arrangements for a tour, please click here to complete the form.