High Quality Content by WIKIPEDIA articles! The Culmback Dam (also known as the George Culmback Dam or the Snoqualmie National Forest Dam) is a large rockfill hydroelectric and water supply dam on the Sultan River, a tributary of the Skykomish River, in Washington. Built in 1965, the dam measures 640 feet (200 m) long at the crest and 262 feet (80 m) high. The elevation of the crest is 1,450 feet (440 m) above sea level. Its reservoir, Spada Lake, provides water for 70 to 75 percent of Snohomish County, and the powerhouse downstream of the dam produces 112 megawatts. Some critics charge that the dam has strongly impacted the runs of salmon and other migratory fish in the Sultan River by depleting gravel and sediment needed to line the riverbed. The dam’s operator counters that Culmback Dam dramatically reduces flooding events, benefiting fish populations and the surrounding communities. The dam was named in honor of George Culmback, a former mayor of Everett.