Skagit Power Development, Skagit River & Newhalem Creek Hydroelectric Project, On Skagit River, Newhalem, Whatcom County, WA

Significance: Developed over a 50 year time span by Seattle City Light, the Skagit River Hydroelectric Project consists of three large dams and power plants: Gorge, Diablo, and Ross. Associated with it is the small Newhalem Creek Hydroelectric Project. Many features of the individual plants were significant in being the first of their type, such as the power tunnel at Gorge in 1924, and some of the country's outstanding engineers were associated with the planning, design, and construction of the facilities. At the time of its construction in 1929, Diablo Dam was the tallest thin arch dam in the world, and Diablo Powerhouse had the world's largest overhead crane. In addition, Seattle City Light's emphasis on presenting a showcase for electricity and efforts at public relations were reflected in the project's design and are unique in the industry.
Unprocessed Field note material exists for this structure: FN-8
Survey number: HAER WA-24
Building/structure dates: 1918-1961 Initial Construction