Planning for the Mossyrock Dam began in the 1940s but opposition from local fishers and
Washington State's Fish and Wildlife Department delayed construction. During
World War II, the city of
Tacoma, Washington, purchased its electricity from the
Bonneville Power Administration and from
Seattle, with costs of up to $1 million/year. To generate its own electricity,
Tacoma City Light (now Tacoma Power) built several dams, including the Mossyrock Dam. Plans for the Mossyrock Dam were announced in 1948 but met stiff opposition. The
Washington State Legislature enacted a fish sanctuary on the Cowlitz River that initially blocked the project. Tacoma City sued, with its suit being raised to the
US Supreme Court a total of three times. After that, construction of the dam was approved. Construction began in 1965 and ended in 1968. On October 13, 1968, the dam's power plant generated its first electricity. Several towns were forced to evacuate ahead of the rising dam waters including
Kosmos,
Nesika, and
Riffe. Tacoma City Light originally proposed naming the facility the "Homer T. Bone Dam", in honor of Senator
Homer Bone of Tacoma. ==Power plant==