The Green and Colorado river flows might seem like a bounty of moisture in a parched desert of sandstone arches and prickly cacti, but in fact it’s just the opposite.

After the driest winter on record, officials this spring want to raise the level of badly depleted Lake Powell on the Colorado River to keep its hydropower humming. To do so, they plan to eventually let out as much as a third of the water in Flaming Gorge Reservoir upstream on the Green River in Wyoming and Utah, which would exceed a record 2022 surge that kept electricity flowing.

Lake Powell, held back by Glen Canyon Dam, supplies inexpensive and carbon-free electricity to more than 350,000 homes. But it comes at a growing cost elsewhere in a contested river basin relied upon heavily by ranchers, industries and some 40 million residential water customers.

At Flaming Gorge in southwestern Wyoming, Buckboard Marina owners Tony and Jen Valdez are eyeing water levels expected to decline by 10 feet (3 meters) by late summer because of the releases. It will mean an ever-longer drive to the water’s edge to launch boats.

“Of course we’re concerned,” Jen Valdez said. “And it will probably get to a point where we’ll need to be more concerned.”

A balancing act to keep up power production

If everything goes to plan — and with no relief from the weather — Flaming Gorge will fall by as much as 27 feet (8 meters) a year from now, leaving Buckboard Marina even more high and dry.

Though it’s likely only a temporary solution amid long-term drought, there will be effects downstream, too, as U.S. Bureau of Reclamation water managers plan to keep more water than usual from flowing out of Lake Powell on the Arizona-Utah line.

Downstream, Lake Mead near Las Vegas is on track to resemble lows four years ago that revealed formerly submerged boats and human remains.

The drastic measures are necessary to keep the Powell waterline high enough to run the power-generation turbines without air getting into the system and causing damage, federal officials say.

Hydropower is a renewable resource — when there’s water

From cities and tribes to rural electric cooperatives and public utility districts, some 155 customers receive hydropower electricity from Glen Canyon Dam and other federal generators. None relies 100% on hydropower.

Many are in disadvantaged communities and all are not-for-profit entities that pay for, among other things, the costs to operate and maintain the dam and the federal government’s investments in it.

The federal Western Area Power Administration has contractual obligations to provide a certain amount of electricity to its customers. A loss of hydropower would require WAPA to seek power elsewhere that likely would be more expensive and not renewable, said Leslie James, executive director of the nonprofit Colorado River Energy Distributors Association.

“If Glen Canyon hydropower is reduced to zero or a low amount, it will have different impacts on what they charge communities,” James said.

It’s a situation James said she hasn’t seen in her 48 years helping electricity customers in Arizona, Colorado, Nevada, New Mexico, Utah and Wyoming.

Replacing federal hydropower with market purchases has forced rate increases for the past five years at Heber Light & Power southeast of Salt Lake City, with the latest increase hitting 13%, said Emily Brandt, the utility’s energy resource manager.

Keeping Lake Powell up could bring environmental costs

Increasingly frequent drought, evaporation and water demand — especially to irrigate alfalfa for the cattle industry — have shrunk the level of Lake Powell to 3,526 feet (1,075 meters) above sea level — just 23% of full capacity.

To keep generating power, the reservoir can’t fall below 3,490 feet (1,200 meters), which is the level of the water intakes for Glen Canyon Dam’s electricity generators.

That has never happened since the 710-foot (220-meter) dam was completed in 1963 and Lake Powell was gradually filled to full capacity in 1980.

In 2022, the Bureau of Reclamation released an unprecedented 500,000 acre-feet (617 million cubic meters) of water from Flaming Gorge to raise Lake Powell. The latest Flaming Gorge releases to maintain Lake Powell’s power generation could eventually total double that amount.

Meanwhile, the plan to hold back 1.5 million acre-feet (1.85 billion cubic meters) in Lake Powell will result in the Hoover Dam producing 40% less electricity at an even lower Lake Mead downstream.

Another downside: Warm water from Lake Powell’s surface could encourage the spread of smallmouth bass, an invasive fish that competes with a threatened native species, the humpback chub, in the Colorado River downstream from Glen Canyon Dam. Groups including the Grand Canyon Trust urge water managers to mix in deeper, cooler water to keep the Grand Canyon inhospitable to smallmouth bass.

A decades-long trend of worsening drought

The strongest releases from Flaming Gorge in the days and weeks ahead will be calibrated to help native fish in the Green River, a Colorado River tributary.

Eventually Flaming Gorge will dip from 83% full to an estimated 59% full. The 2022 releases from Flaming Gorge were followed by a wet winter, which alleviated water worries across the region for a time.

“We kind of got saved by Mother Nature,” said Valdez, the Buckboard Marina owner.

A wet year or two won’t be enough to reverse a quarter-century-long “ megadrought ” resulting at least in part from human-caused climate change. But Valdez is optimistic that wet weather will return like before.

“Hopefully we can expand into doing some other things,” Valdez said. “Because it’s going to come back eventually.”

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Pineda reported from Los Angeles.

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