Nine Mile Dam

Nine Mile Falls Dam is a dam on the Spokane River, in the unincorporated community of Nine Mile Falls, Washington. It was built on the site of the falls in 1908, creating Nine Mile Reservoir. The dam was designed by the New York engineering firm of Sanderson & Porter, and originally constructed to satisfy the power needs of the Spokane and Inland Empire Railroad interurban trolley lines.Washington Water Power (now the power company Avista) purchased the site in 1925, and continues to operate it as one of its six hydroelectric generating plants on the Spokane River. The 58-foot-high cyclopean masonry dam and its powerhouse, storehouse, ten cottages and other structures were placed on the National Register of Historic Places in 1990.