Running out of time and options to save water along the drying Colorado River, federal officials said they’re considering whether to release less water from the country’s two largest reservoirs downstream to Arizona, California and Nevada.
Without enough snow this winter, the water level at Lake Powell — the country’s second-largest reservoir — will drop below a critical level by next November, according to a new report from the U.S. Bureau of Reclamation. Below that point, the Glen Canyon Dam will no longer be able to generate electricity and experts worry whether conditions will worsen to the point that the structure will no longer be able to send water downstream at all.
Conditions on the Colorado River are worsening quicker than expected. The seven states in the river basin made little progress saving water over the summer and Colorado is heading into its third La Niña winter in a row, likely indicating below-average snowpack. A worst-case scenario, once considered only as a hypothetical, now presents a very real threat.
“It’s going to be ugly,” Mark Squillace, a water law professor at the University of Colorado, said. “The bottom line is there just isn’t going to be enough water available.”
The path forward for Reclamation, the states and dozens of Native American tribes is narrowing, Brad Udall, a water and climate scientist with Colorado State University, said, calling the implications “beyond serious.”
If the federal government comes in too strong, requiring massive cuts to water use, the entire scheme could devolve into a morass of expensive and time-consuming lawsuits, Udall said. Not strong enough and the river dwindles further, endangering the way of life for more than 40 million people and an estimated $1.4 trillion chunk of the national economy.
Reclamation officials announced Friday that they will consider whether to turn down the faucet for downstream states next year and in 2024. A draft plan should be ready by spring.
“The Interior Department continues to pursue a collaborative and consensus-based approach to addressing the drought crisis affecting the West,” Secretary of the Interior Deb Haaland said in a news release. “At the same time, we are committed to taking prompt and decisive action necessary to protect the Colorado River and all those who depend on it.”
Additional information from Reclamation officials was not immediately available.
Especially in recent years, the upper-basin states of Colorado, New Mexico, Utah and Wyoming have repeatedly pointed to the lower-basin states of Arizona, California and Nevada as the main source of imbalance within the basin. Arizona and California specifically have been using more water than they’re allotted for years while the upper-basin states have always used less than they’re allowed.
Federal officials are unlikely to step in and order specific cuts from major water users like the Imperial Irrigation District in California or cities like Los Angeles and Phoenix. Instead, the agency’s power rests within the massive reservoirs holding the water supply to those downstream states and Mexico, Squillace said.
By reducing the amount of water reduced downstream, Reclamation can push states to absorb the cuts without dictating how they do it.
Squillace estimated that Reclamation appears likely to lean on an existing outline of water-saving measures to make the process even more palatable and to avoid being sued by unhappy states or water managers.
That framework began in the first few years of the ongoing megadrought, which started drying the American West around 2000, about the same time that the region’s demand for water surpassed its supply. The seven states agreed in 2007 to what are now known as the Interim Guidelines, setting limits to how low Lake Mead’s water elevation can drop before supply to Arizona, Nevada and Mexico will be cut. With that plan, California’s share, the largest in the basin, wouldn’t change.
The drought worsened still and the states agreed to more cuts in 2019, including steps to cut California’s water supply, and then again in 2021.
The agreements combined into five tiers of cuts, increasing in severity as Lake Mead sinks lower. To date, three of those tiers have been triggered and Squillace said he anticipates Reclamation to expedite the remaining two, which would save nearly 1.4 million acre-feet.
For context, an acre-foot is a volumetric measurement of water, a year’s worth for two average families of four. That potential 1.4 million acre-feet falls short when held up to the range of 2 million to 4 million acre-feet Reclamation has asked the seven states to save.
Other offers from Arizona, California and Native American tribes in the lower basin might push water savings over the 2 million acre-foot mark, Rhett Larson, a water law professor at Arizona State University, said. But those deals aren’t finalized yet and it’s unclear if they’d remain on the table if federal officials move first.
All these savings might be enough to avoid the worst-case scenario by next November, Jennifer Gimbel, senior water policy scholar at Colorado State University, said.
The worst at the moment appears to be if the water elevation at Lake Powell were to drop below 3,490 feet, which is a possible — if unlikely — scenario without enough snow this winter, according to a 24-month study released by Reclamation officials last month. Below that point, the Glen Canyon Dam can no longer generate electricity, which would almost certainly trigger rate increases, particularly for poor, rural and indigenous communities in the region.
Just below that elevation sit the tubes through which the dam normally releases water downstream through the Grand Canyon and into Arizona, Nevada, California and Mexico, Udall said. If water continues to sink, federal officials will have to switch from those tubes to a largely untested emergency bypass system.
“They’ve never been operated year in and year out,” Udall said.
During a flood in 1983, a small flaw in the dam’s emergency spillways caused a devastating phenomenon called cavitation, which tore apart the structure’s concrete, threatening the entire system.
Should something similar happen again the bypass tubes might have to be shut down, meaning federal officials could not pass any water from Lake Powell downstream, Udall said.
“We cannot even risk a small chance of that happening,” he said.
Even if a slew of potential cuts can help keep Powell afloat, more will have to be done to save the region moving forward, Gimbel noted.
“These are temporary measures. That’s the frustration for so many people right now, we have to take care of the immediate problem and we know it’s not a long-term solution,” Gimbel said. “Mother nature is teaching us how to be humbled.”
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