See Inside Lake Powell’s Glen Canyon Dam

This article was originally published by High Country News.

By Luna Anna Archey / High Country News

Glen Canyon Dam was built primarily to store excess Colorado River water during wet years, so it could be released during dry spells and used to generate power. Now, with aridification depriving the river of those excess flows, both functions are imperiled. In April, Lake Powell fell perilously close to the point at which dam operators would have to stop sending water through the turbines, depriving the grid of enough electricity to power about a quarter of a million homes annually. It would also drain between $100 million and $200 million annually from dam electricity sales, some of which helps fund endangered species recovery, salinity control and water studies on the Colorado River. Officials have released extra water from upstream dams and are currently letting less of it flow through Glen Canyon Dam, raising water levels just enough to keep the turbines spinning. —Jonathan Thompson

Glen Canyon Dam’s intake points for the water to power the plant’s eight turbines will be above the water line — the minimum power pool — if the lake level drops another 33 feet. If that happens, the plant will not be able to generate power, though it would need to be maintained in case the water level rises in the future.

See the full photo story on the High Country News website.