Water Resources
National finalist
Gold Award

Anchor QEA

Project: Lake Chelan Hydroelectric Project
Client: Chelan County Public Utility District

Photo courtesy of Anchor QEA
Anchor QEA designed and constructed a new fish habitat channel in the lower Chelan River.

When the time came for the Chelan County Public Utility District to renew its long-term operating license for the Lake Chelan Hydroelectric Project, it first had to forge a partnership with the numerous stakeholders that had evolved over more than 70 years of hydroelectric operations — state and federal agencies, American Indian tribes, environmental groups, fishermen, kayakers and local communities — while maintaining the capacity to generate electricity for some 20,000 homes in the area.

The need was for more water, colder water and better spawning habitats for cutthroat trout and salmon.

Anchor QEA’s task was to enhance flows in the lower Chelan River and create a spawning area by taking water that had already passed through the powerhouse turbines and pumping it up to the head of the lower reach of the river. This allowed water to be used both for power generation and for the fisheries habitat.

The firm also designed and constructed a new habitat channel within the existing Chelan River channel, replicating a natural channel with gravel sizes suitable for spawning, providing favorable flow depths and velocities, and creating channel complexity by adding features such as boulders and large woody debris along with riparian vegetation. An engineered log jam and grouted boulder sill were also added to help divert high flows away from the new channel.

Within weeks of the opening of the new habitat, more than 250 Chinook salmon spawning nests were counted, a clear sign of success.

“Restoring the lower Chelan River and riparian habitat will allow the public and scientists to better understand how restoration can work with a little help from humans,” said Tom Tebb, director of the state Department of Ecology’s Central Regional Office.

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