PAGE, Ariz. - The first sign of serious trouble for the drought-stricken American Southwest could be a whirlpool.
It could happen if the surface of Lake Powell, a man-made reservoir along the Colorado River that's already a quarter of its former size, drops another 38 feet down the concrete face of the 710-foot Glen Canyon Dam here. At that point, the surface would be approaching the tops of eight underwater openings that allow river water to pass through the hydroelectric dam.
The normally placid Lake Powell, the nation's second-largest reservoir, could suddenly transform into something resembling a funnel, with water circling the openings, the dam's operators say.
If that happens, the massive turbines that generate electricity for 4.5 million people would have to shut down - after nearly 60 years of use - or risk destruction from air bubbles. The only outlet for Colorado River water from the dam would then be a set of smaller, deeper and rarely used bypass tubes with a far more limited ability to pass water downstream to the Grand Canyon and the cities and farms in Arizona, Nevada and California.
Such an outcome - known as a "minimum power pool" - was once unfathomable here. Now, the federal government projects that day could come as soon as July.
Worse, officials warn, is the possibility of an even more catastrophic event. That is if the water level falls all the way to the lowest holes, so only small amounts could pass through the dam. Such a scenario - called "dead pool" - would transform Glen Canyon Dam from something that regulates an artery of national importance into a hulking concrete plug corking the Colorado River.
Anxiety about such outcomes has worsened this year as a long-running drought has intensified in the Southwest. Reservoirs and groundwater supplies across the region have fallen dramatically, and states and cities have faced restrictions on water use amid dwindling supplies. The Colorado River, which serves roughly 1 in 10 Americans, is the region's most important waterway.
The 1,450-mile river starts in the Colorado Rockies and ends in the Sea of Cortez in Mexico. There are more than a dozen dams along the river, creating major reservoirs such as Lake Powell and Lake Mead.
On the way to such dire outcomes at Lake Powell - which federal officials have begun both planning for and working aggressively to avoid - scientists and dam operators say water temperatures in the Grand Canyon would hit a roller coaster, going frigid overnight and then heating up again, throwing the iconic ecosystem into turmoil. Lake Powell's surface has already fallen 170 feet.
Lucrative industries that attract visitors from around the world - the rainbow trout fishery above Lees Ferry, rafting trips through the Grand Canyon - would be threatened. And eventually the only water escaping to the Colorado River basin's southern states and Mexico could be what flows into Lake Powell from the north and sloshes over the lip of the dam's lowest holes.
"A complete doomsday scenario," said Bob Martin, deputy power manager at Glen Canyon Dam, as he peered down at the shimmering blue of Lake Powell from the rim of the dam.
- - -
'A catastrophe for the entire system'
In August, the Bureau of Reclamation announced it would support studies to find out if physical modifications could be made to Glen Canyon Dam to allow water to be released below critical elevations, including dead pool. That implies studying such costly and time-consuming construction projects as drilling tunnels through the Navajo sandstone at river level, said Jack Schmidt, a Colorado River expert at Utah State University.
"There was a time in my professional career that if anybody from Reclamation ever said that, they'd be fired on the spot," said Schmidt, who served as the chief of the U.S. Geological Survey's Grand Canyon Monitoring and Research Center during the Obama administration. Even raising that issue is "a huge sea change telling you how different the world is."
This year, the Biden administration called on the seven states of the Colorado River basin to cut water consumption by 2 to 4 million acre-feet - up to a third of the river's annual average flow - to protect power generation and avoid such dire outcomes. But negotiations have not produced an agreement. And the Interior Department has not yet mandated those cuts, despite missing its own August deadline to reach an agreement.
But these types of ominous scenarios are starting to be considered. With Lake Powell at one-quarter full, Reclamation has begun a feasibility study on the prospect of harnessing the deeper bypass tubes for power generation. The entity that markets Glen Canyon's electricity - the Western Area Power Administration, known as WAPA and part of the Energy Department - is working with two national laboratories to assess what electricity would be available for purchase if Glen Canyon shut down.
And construction is also underway on a project to install deeper pipes to protect the city of Page, Ariz., and its 7,000 residents, from losing its supply of drinking water.
The chances of hitting minimum power pool (lake elevation 3,490 feet above sea level) within the next two years is part of Reclamation's minimum probable forecast, and more likely scenarios have water levels staying above that threshold. But researchers including Schmidt have documented how Reclamation's projections have been too optimistic in recent years amid the warming climate and historic drought that is wringing water out of the West on a grand scale.
"The critical part about what's been happening and what climate change is forcing us to do is: We have to look more at the extremes," said Tom Buschatzke, director of Arizona's Department of Water Resources, said in an interview. "We've got to plan for the low end."
Reclamation said in a statement it now relies on a more recent 30-year climatology window - 1991 to 2020 - to make forecasts, which leaves out the wet years of the 1980s and incorporates more drought, which "will improve accuracy and remove some biases."
Buschatzke has also been raising the alarm about Lake Powell reaching dead pool - an elevation 120 feet below the threshold for producing power.
"It is a possibility. I can't tell you the probability," he said. "But that's an outcome that would be not only an ecological disaster, but the world would have its attention on such an outcome in a very negative way."
If that happens, "you're not going to have a river," he added. "It would be a catastrophe for the entire system."
- - -
'Huge problems for the Grand Canyon'
In the 23rd year of the Western drought, Lake Powell's once crowded boat ramps end in sand. Dirt bikes roar across newly exposed shores. Exquisite arches and rock formations, lost when the reservoir filled in the 1960s, are re-emerging.
As the water has receded, so has the ability to produce power at Glen Canyon, as less pressure from the lake pushes the turbines. The dam already generates about 40 percent less power than what has been committed to customers, which includes dozens of Native American tribes, nonprofit rural electric cooperatives, military bases, and small cities and towns across several southwestern states. These customers would be responsible for buying power on the open market in the event Glen Canyon could not generate, potentially driving up rates dramatically.
The standard rate paid for Glen Canyon's low-cost power is $30 per megawatt hour. On the open market, these customers last summer faced prices as high as $1,000 per megawatt hour, said Leslie James, executive director of the Colorado River Energy Distributors Association.
"That will be very financially damaging," said Bryan Hill, the utility manager for Page, one of the cities that relies on the dam's low-cost hydropower for one-third to half of its electricity needs. "Huge, for everybody. For businesses. For single moms. It will be a financial hardship."
Glen Canyon's electricity is important for the nation in other ways. The dam is what's known as a "black start" facility for the country's largest nuclear plant, the Palo Verde Generating Station in Arizona. This means the dam could bring the nuclear plant back online if it shut down and needed to restart.
In September, Glen Canyon sent about 80 megawatts of power to California for three hours at the height of its record-breaking heat wave, helping the state narrowly avoid rolling blackouts. It was the second time in the past few years that the dam has been called on to ramp up during emergencies threatening the electric grid, said Adam Arellano, an executive with the Western Area Power Administration.
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It could happen if the surface of Lake Powell, a man-made reservoir along the Colorado River that's already a quarter of its former size, drops another 38 feet down the concrete face of the 710-foot Glen Canyon Dam here. At that point, the surface would be approaching the tops of eight underwater openings that allow river water to pass through the hydroelectric dam.
The normally placid Lake Powell, the nation's second-largest reservoir, could suddenly transform into something resembling a funnel, with water circling the openings, the dam's operators say.
If that happens, the massive turbines that generate electricity for 4.5 million people would have to shut down - after nearly 60 years of use - or risk destruction from air bubbles. The only outlet for Colorado River water from the dam would then be a set of smaller, deeper and rarely used bypass tubes with a far more limited ability to pass water downstream to the Grand Canyon and the cities and farms in Arizona, Nevada and California.
Such an outcome - known as a "minimum power pool" - was once unfathomable here. Now, the federal government projects that day could come as soon as July.
Worse, officials warn, is the possibility of an even more catastrophic event. That is if the water level falls all the way to the lowest holes, so only small amounts could pass through the dam. Such a scenario - called "dead pool" - would transform Glen Canyon Dam from something that regulates an artery of national importance into a hulking concrete plug corking the Colorado River.
Anxiety about such outcomes has worsened this year as a long-running drought has intensified in the Southwest. Reservoirs and groundwater supplies across the region have fallen dramatically, and states and cities have faced restrictions on water use amid dwindling supplies. The Colorado River, which serves roughly 1 in 10 Americans, is the region's most important waterway.
The 1,450-mile river starts in the Colorado Rockies and ends in the Sea of Cortez in Mexico. There are more than a dozen dams along the river, creating major reservoirs such as Lake Powell and Lake Mead.
On the way to such dire outcomes at Lake Powell - which federal officials have begun both planning for and working aggressively to avoid - scientists and dam operators say water temperatures in the Grand Canyon would hit a roller coaster, going frigid overnight and then heating up again, throwing the iconic ecosystem into turmoil. Lake Powell's surface has already fallen 170 feet.
Lucrative industries that attract visitors from around the world - the rainbow trout fishery above Lees Ferry, rafting trips through the Grand Canyon - would be threatened. And eventually the only water escaping to the Colorado River basin's southern states and Mexico could be what flows into Lake Powell from the north and sloshes over the lip of the dam's lowest holes.
"A complete doomsday scenario," said Bob Martin, deputy power manager at Glen Canyon Dam, as he peered down at the shimmering blue of Lake Powell from the rim of the dam.
- - -
'A catastrophe for the entire system'
In August, the Bureau of Reclamation announced it would support studies to find out if physical modifications could be made to Glen Canyon Dam to allow water to be released below critical elevations, including dead pool. That implies studying such costly and time-consuming construction projects as drilling tunnels through the Navajo sandstone at river level, said Jack Schmidt, a Colorado River expert at Utah State University.
"There was a time in my professional career that if anybody from Reclamation ever said that, they'd be fired on the spot," said Schmidt, who served as the chief of the U.S. Geological Survey's Grand Canyon Monitoring and Research Center during the Obama administration. Even raising that issue is "a huge sea change telling you how different the world is."
This year, the Biden administration called on the seven states of the Colorado River basin to cut water consumption by 2 to 4 million acre-feet - up to a third of the river's annual average flow - to protect power generation and avoid such dire outcomes. But negotiations have not produced an agreement. And the Interior Department has not yet mandated those cuts, despite missing its own August deadline to reach an agreement.
But these types of ominous scenarios are starting to be considered. With Lake Powell at one-quarter full, Reclamation has begun a feasibility study on the prospect of harnessing the deeper bypass tubes for power generation. The entity that markets Glen Canyon's electricity - the Western Area Power Administration, known as WAPA and part of the Energy Department - is working with two national laboratories to assess what electricity would be available for purchase if Glen Canyon shut down.
And construction is also underway on a project to install deeper pipes to protect the city of Page, Ariz., and its 7,000 residents, from losing its supply of drinking water.
The chances of hitting minimum power pool (lake elevation 3,490 feet above sea level) within the next two years is part of Reclamation's minimum probable forecast, and more likely scenarios have water levels staying above that threshold. But researchers including Schmidt have documented how Reclamation's projections have been too optimistic in recent years amid the warming climate and historic drought that is wringing water out of the West on a grand scale.
"The critical part about what's been happening and what climate change is forcing us to do is: We have to look more at the extremes," said Tom Buschatzke, director of Arizona's Department of Water Resources, said in an interview. "We've got to plan for the low end."
Reclamation said in a statement it now relies on a more recent 30-year climatology window - 1991 to 2020 - to make forecasts, which leaves out the wet years of the 1980s and incorporates more drought, which "will improve accuracy and remove some biases."
Buschatzke has also been raising the alarm about Lake Powell reaching dead pool - an elevation 120 feet below the threshold for producing power.
"It is a possibility. I can't tell you the probability," he said. "But that's an outcome that would be not only an ecological disaster, but the world would have its attention on such an outcome in a very negative way."
If that happens, "you're not going to have a river," he added. "It would be a catastrophe for the entire system."
- - -
'Huge problems for the Grand Canyon'
In the 23rd year of the Western drought, Lake Powell's once crowded boat ramps end in sand. Dirt bikes roar across newly exposed shores. Exquisite arches and rock formations, lost when the reservoir filled in the 1960s, are re-emerging.
As the water has receded, so has the ability to produce power at Glen Canyon, as less pressure from the lake pushes the turbines. The dam already generates about 40 percent less power than what has been committed to customers, which includes dozens of Native American tribes, nonprofit rural electric cooperatives, military bases, and small cities and towns across several southwestern states. These customers would be responsible for buying power on the open market in the event Glen Canyon could not generate, potentially driving up rates dramatically.
The standard rate paid for Glen Canyon's low-cost power is $30 per megawatt hour. On the open market, these customers last summer faced prices as high as $1,000 per megawatt hour, said Leslie James, executive director of the Colorado River Energy Distributors Association.
"That will be very financially damaging," said Bryan Hill, the utility manager for Page, one of the cities that relies on the dam's low-cost hydropower for one-third to half of its electricity needs. "Huge, for everybody. For businesses. For single moms. It will be a financial hardship."
Glen Canyon's electricity is important for the nation in other ways. The dam is what's known as a "black start" facility for the country's largest nuclear plant, the Palo Verde Generating Station in Arizona. This means the dam could bring the nuclear plant back online if it shut down and needed to restart.
In September, Glen Canyon sent about 80 megawatts of power to California for three hours at the height of its record-breaking heat wave, helping the state narrowly avoid rolling blackouts. It was the second time in the past few years that the dam has been called on to ramp up during emergencies threatening the electric grid, said Adam Arellano, an executive with the Western Area Power Administration.
Officials fear 'complete doomsday scenario' for drought-stricken Colorado River
PAGE, Ariz. - The first sign of serious trouble for the drought-stricken American Southwest could be a whirlpool. It could happen if the surface of Lake Powell, a man-made reservoir along the Colorado River that's already a quarter of its former size, drops another 38 feet down the concrete face...
