Risks to the Glen Canyon Dam that the resulting flood would scour the bottom few hundred feet of the Grand Canyon, overtop Hoover Dam, and cause severe damage all along the lower Colorado River. In the event of a complete dam failure with Lake Powell at high pool, about of water would surge out of Lake Powell at an initial depth of over . Downstream communities and perhaps every dam along the river, excluding possibly Hoover Dam, as well as riverside lowlands, would be inundated or severely damaged. Located downstream from Glen Canyon Dam are Hoover Dam forming Lake Mead, Davis Dam forming Lake Mohave, Parker
Black Canyon Diversion Dam Black Canyon Diversion Dam Black Canyon Diversion Dam (National ID # ID00282) is a dam in Gem County, Idaho. The concrete dam was originally completed in 1924, then re-constructed between 1951 and 1955, by the United States Bureau of Reclamation. Its structure has a height of 183 feet, and a length of 1902 feet at its crest. It impounds the Payette River for the diversion of water into the Black Canyon and North Side Main irrigation canals, and the generation of about 2 megawatts of hydroelectric power, part of the Bureau's larger Boise Project. The dam is owned and operated