Drought threatens coal plant operations — and electricity — across the West

Driving through the Wyoming sagebrush west of Cheyenne, the clouds of dust rising from the road give way to giant plumes of steam shooting into the warming sky.

This is the Jim Bridger power plant, one of the largest coal-fired power sources in the nation and an enormous emitter of carbon dioxide pollution. At the plant's edge there's a reservoir, lined with rocks and clumps of drying grass. The plant sucks up about 16 million barrels of water each day, using it to power more than million homes across six western states, all the way to Oregon.

But there's a problem that looms for the coal plant operator and the customers that rely on it for electricity. This water is piped here from the Green River, a tributary of the rapidly shrinking Colorado River. Now, amidst a decades-long drought and a shortage of water downstream across the Southwest, future conservation in the basin could mean industrial users like Jim Bridger see their water shut off, says Wyoming State Engineer Brandon Gebhart.

"They would be likely the first one shut off. Unless they were able to find a different source of water, we would have to just shut off their water and not allow them to divert," Gebhart says.

The western U.S. hasn't been this dry for more than 1,200 years, but 30 western coal plants continue to suck up 156 million gallons a day of the region's scarce water, according to the Energy Information Administration. Now the very plants whose emissions help drive climate change are at risk of shutdowns, because the water they need to operate has fallen to unprecedented levels.

Some utilities are already sending warnings, telling federal regulators that the drought could threaten coal plant operations. But there's uncertainty at the state level over which officials are responsible for managing drought risk to power plants and the threat of brownouts and blackouts.

Old coal plants like Jim Bridger have for decades been critical to the grid, says David Eskelsen, spokesman for Rocky Mountain Power, a division of PacifiCorp, which operates the Wyoming plant. "With all the concerns about the use of fossil fuels, climate change, and the use of water in this way," Eskelsen says, "that has to be balanced against the role that these particular power plants play in the stability of the regional transmission system."

But rising water scarcity in the West means the stability of coal plants like Jim Bridger is no longer a sure thing, says Joe Smyth, research manager at the Energy and Policy Institute, a utility watchdog group.

"If you don't have water to cool it, you can't run it, right? Like it's not a minor risk. It is a very disruptive event," he says, "If you're not aware of those risks, then you are not really operating your power plants responsibly."

Who ensures that coal plants have enough water?

Drought threatens coal plant operations and customers across the US. Earlier this year in its reliability assessment, the North American Electric Reliability Corporation issued a warning that drought in the Missouri River Basin could affect power plants, including coal plants, that use river water for cooling. In the west, the risk of low water is leading to new alerts for Wall Street investors.

In its latest filing with the Securities and Exchange Commission, New Mexico utility PNM outlines the risks of drought to its coal plants on the San Juan river, a tributary of the Colorado. "If inadequate precipitation occurs in the watershed that supplies that region, PNM may have to decrease generation at these plants," the utility writes, "Drought conditions or actions taken by the court system, regulators, or legislators could limit PNM's supply of water, which would adversely impact PNM's business."

But for a coal plant like Jim Bridger, it can be unclear who is regulating this risk at ground-level, where power shortages could affect millions of Americans.

The Wyoming Public Service Commission (PSC) officially regulates plant operator Rocky Mountain Power, but the PSC's chief counsel John Burbridge tells NPR his office has not taken steps to ensure there's enough water to keep the power on. He says the PSC defers to the state engineer. "We trust that once [the utilities] have the state engineer's permit they do have enough water," Burbridge says, "You know it's the old Ronald Reagan thing, 'Trust, but verify.'"

But the state engineer Gebhart says a water right isn't a promise of water forever for coal plants. "The granting of a water right does not guarantee an amount of water," he says. "It allows them to use water when it's available."

Gebhart's office gave Jim Bridger its water rights from the Green River in 1968 – the coal plant started operating in 1974. In the scheme of Wyoming's Green River Basin, that isn't very old. Some local farms have water rights dating back to the 1880s, and they would have the seniority to keep their water over relatively newer users like Jim Bridger, Gebhart says.

Last week Wyoming and other upper basin states of the Colorado River missed the federal government's deadline to propose cuts to help with the low water levels downstream at Lake Powell and Lake Mead.

It's still unclear when this possible diversion of Colorado River water from the upper basin could happen. Eskelsen notes that Jim Bridger has a "contingency" at another nearby reservoir – although it, too, is on the Green River and also could be at risk. Ultimately while coal plants like Jim Bridger can ask the state engineer for guidance, they're on their own to make sure they have water supplies to keep operating into the future, says water expert Patrick Tyrrell, the former Wyoming state engineer. "That's not the state engineer's job," he says, "The primary responsibility is on them themselves."

Future plans for Western coal plants

The Jim Bridger coal plant isn't scheduled to close for good until 2037. The Biden administration is aiming for a fossil-free electric grid by 2035. While some Western states like Colorado have committed to shutting down all their coal plants in the next decade, others are considering a different direction.

States like Wyoming, which produces about 40% of the country's coal, hope to keep their coal plants running using new technology that would compress and trap their carbon emissions underground before they escape and cause global warming. In recent years, Wyoming's legislature has mandated that utilities with coal plants explore installing "carbon capture and sequestration" technology. And landmark federal climate legislation features new incentives for carbon capture and storage, including upping the tax credit for storing carbon emissions underground from $50 to as much as $85 per ton.

But installing this technology in a mega-drought that shows no signs of relenting poses serious risks, says Avner Vengosh, professor of environmental quality at Duke University. Carbon capture requires even more water than these Western coal plants already use. In a recent filing with the Wyoming Public Commission, PacifiCorp estimates that carbon capture increases a coal plant's water usage by about 35-40%.

Regardless of what happens with carbon capture and storage, Rocky Mountain Power plans to convert two of Jim Bridger's four units from coal to natural gas in 2023. But even with gas as a fuel instead of coal, the plant would still use the same amount of water, says Eskelsen. "The boiler is still the same and the cooling cycle is still the same," he says.

Locals push for less water-intensive energy

About 50 miles southwest of the Jim Bridger coal plant on the Green River is the Buckboard Marina. Families drive their boats down a long steep road to get to the shore.

Because of the drought, the water has dropped about six feet from a year ago, says Tony Valdez, co-owner of the marina, pointing to the old waterline where the sagebrush abruptly turns to sand. Now Valdez and his wife and co-owner, Jen Valdez, must continuously gauge the water to adjust the ramp to the boats. "It's just straight down," she says. "It's like a slip and slide."

Last month, the Valdez family attended a meeting at a local middle school with farmers, ranchers, and another marina owner about the shortage of water in the Colorado River Basin. "With our water dropping, you know our concern is, where's our marina go?" Tony Valdez asks, "Where's the water come from, if it ain't falling from the sky?"

This drought has forced new questions about the water intensity of energy sources throughout the Colorado basin, says Wahleah Johns, the director of the office of Indian energy policy at the Department of Energy. She says that's particularly true in the Navajo or Diné Nation, which is shifting away from coal. The Four Corners power plant, not scheduled to close until 2031, draws from the San Juan River, part of the dwindling Colorado River basin. Johns says as the Diné consider alternative energies, they're thinking about the legacy of coal, water, and pollution.

"The biggest question that communities had is, 'How much water is this gonna use?' And particularly around solar power in comparison to coal." While solar needs some water in the production of the panels, it doesn't have a water footprint once it is installed. "We had to show, you know, very little water is gonna be used."

Johns is a member of Diné nation, "My family, we haul water, we don't have access to water. I mean [close to] 40% of my nation has to haul water every other day," she says, "Those folks have an understanding of how precious water is."

Back at the marina in Wyoming, Tony Valdez remembers his life working in coal plants, including Jim Bridger. "My dad worked in 'em, my brother worked in 'em, I worked in 'em." Valdez knows how much water coal plants use and says that's why he's interested in renewable energy.

"So why are we still pushing that sh*t up in the air when we have wind, we have solar, we have all this stuff that does not impact water?" he asks, "We're pumping water through pipes to power plants to produce power, when there's so many other things that you could possibly do."

This reporting was supported with a grant from The Water Desk at the University of Colorado Boulder. [Copyright 2022 NPR]