Lake Powell could lose the ability to generate power by early 2027

Water levels near historic lows at Lake Powell have caused concerns about the reservoir’s ability to generate power.

The reservoir on the Arizona-Utah border sits at an elevation of about 3,522 feet, roughly 3 feet above the record low set in April 2023.

And conditions are deteriorating quickly. A new federal forecast released projects that Lake Powell will receive just 2% of its average inflow this month.

For the full water year, inflow is expected to reach only 36% of the 30-year average.

The U.S. Bureau of Reclamation has said it intends to keep the reservoir above 3,500 feet because Glen Canyon Dam hits minimum power pool at 3,490 feet, the point at which it can no longer reliably generate hydropower.

Below that level, water can only be released through the river outlet works, bypassing the power plant entirely.

“Those waters bypass the power plant, take water out at a lower elevation and that water just goes right out into the river,” said Jack Schmidt, director of the Center for Colorado River Studies at Utah State University.

Operating that close to minimum power pool also threatens the dam’s infrastructure. The bureau has said that when water drops to 3,490 feet, air gets pulled into the current the way it would in a whirlpool.

That air forms tiny bubbles that can wreak havoc inside the dam’s turbines, a phenomenon known as cavitation.

“Those little air bubbles, when they explode in the turbine, they create shock waves that destroy the turbines,” Schmidt told KTAR News 92.3 FM.

Glen Canyon Dam provides power for about 5 million people across the Southwest.

The bureau’s projections show Lake Powell could hit minimum power pool as soon as March 2027.

What’s being done to stabilize the reservoir

Schmidt compared the second-largest reservoir in the U.S. to a bathtub.

“How do you regulate water in a bathtub? You either open the faucet, or you shut down the drain,” Schmidt said.

He said the faucet represents water that flows into the reservoir through the natural watershed and from upstream releases.

In April, the bureau announced it would release up to 1 million acre-feet of water from Flaming Gorge Reservoir on the Wyoming-Utah border to help prop up Lake Powell, but the additional water did little to reverse the trend.

“The releases from Flaming Gorge have slowed the rate of decline, but they have not stopped it,” Schmidt said.

To plug the drain, the bureau said it would reduce releases from Lake Powell to Lake Mead by nearly 1.5 million acre-feet.

That tradeoff carries its own consequences.

“The implications of this mean less water being released into the Grand Canyon. This affects commercial river running, this affects the Grand Canyon ecosystem,” Schmidt said.

The seven states that share the Colorado River are negotiating a new operating agreement that would govern how they divide a shrinking supply.

An announcement is expected soon.

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