Desperate measures: Advocates weigh draining Lake Powell to fill Colorado River

As the Southwestern United States battles a 27-year drought — the longest in 1,200 years — and the Colorado River gets drier and drier, some advocates are pushing for a drastic action: draining Lake Powell, one of the river’s two key reservoirs. Draining the reservoir and letting all its water flow into Lake Mead could reduce evaporation losses by a couple hundred thousand acre-feet, increase hydropower production at Lake Mead and reveal sites sacred to Indigenous people, which the man-made Lake Powell obscures. 

The Glenn Canyon Dam created Lake Powell. Pipes in the dam send water down to turbines, which generate energy, and then into the Colorado River. However, once Lake Powell’s water level dips too low, water can't escape through the main pipes. “Allowing more water to flow through the Glen Canyon Dam — by draining the lake through the existing bypass tubes and newly drilled diversion tunnels near the riverbed — is no longer dismissed out of hand,” Jim Robbins writes for Yale Environment 360. 

The plan to drain Lake Powell, called Fill Mead First, faces many obstacles. The federal government does not include draining the lake as an option in its ten-year plan to manage the Colorado River, and new diversion tunnels would likely take decades to build and cost billions. However, the Glen Canyon Institute is in support of the plan, and Jack Schmidt, director of the Center for Colorado River Studies at Utah State University, said drilling lower pipes is “an utterly reasonable idea.”