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 of the Gunnison National Park Black Canyon of the Gunnison National Park Black Canyon of the Gunnison National Park is an American national park located in western Colorado and managed by the National Park Service. There are two primary entrances to the park: the south rim entrance is located east of Montrose, while the north rim entrance is south of Crawford and is closed in the winter. The park contains of the long Black Canyon of the Gunnison River. The national park itself contains the deepest and most dramatic section of the canyon, but the canyon continues upstream into Curecanti National Recreation Area and downstream