As drought shrivels Lake Powell, millions face power crisis

Lake Powell, a reservoir created by flooding the Colorado River, in the 22nd year of a mega drought. Photograph: John Gastaldo/ZUMA Press Wire/REX/Shutterstock

Bob Martin, the deputy power manager at the Glen Canyon dam, gestures at the band of whitish, chalky residue running along the steep canyon walls towering above the Colorado River.

“That’s where the water level used to be,” says Martin. “It’s fallen lower than even the lowest end of the scale thought possible when the dam was constructed.”