The future of the American west hung in the balance after seven states remained at a stalemate over who should bear the brunt of the enormous water cuts needed to pull the imperiled Colorado River back from the brink.
Negotiators, who have spent years trying to iron out thorny disagreements, ended their talks on Friday without a deal – one day before a critical deadline to form a plan that had been set for Saturday.
The end of these talks has thrust the basin, and those who rely on its essential water resources, into uncertain territory.
In the region where water has long been the source of survival and conflict, the challenges that hindered consensus were as steep as the stakes are high.
Snaking across 1,450 miles (2,300km) from the Rocky Mountains into Mexico, the Colorado supplies roughly 40 million people in seven states, 5.5m acres (2.23m hectares) of farmland and dozens of tribes. The waters fuel an estimated $1.4tn in economic activity, and raised bustling cities, including Los Angeles, Phoenix and Las Vegas. The sprawling basin is also home to diverse ecosystems, with scores of birds, fish, plants and animals, and provides critical habitat for more than 150 threatened or endangered species.
But the river has been overdrawn for more than a century. As demand continues to grow, rising temperatures and lower precipitation caused by the climate crisis are taking an increasingly larger share of declining supplies, a trend only expected to worsen as the world warms.
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Up to 4m acre-feet of cuts are needed to bring the basin back into balance – an amount equal to more than a quarter of its annual average flow. One acre-foot, a unit denoting the amount of water that can cover a football field one foot deep, is equal to roughly 326,000 gallons – enough to supply roughly three families for a year.
A record snow drought plaguing the region this year is expected to reduce water supplies further, which added another layer of urgency to the talks.
“There needs to be unbelievably harsh, unprecedented cuts” that will affect water users in major ways, said Dr Brad Udall, senior water and climate research scientist at Colorado State University’s Colorado Water Center. “Mother Nature is not going to bail us out.”
Colorado, Utah, Wyoming and New Mexico, which form the upper-basin states – have resisted any cuts to their share, insisting lower-basin states – California, Arizona and Nevada – are responsible for creating the deficit. Because they are situated closer to the headwaters, their supply doesn’t come from the reservoirs that the lower basins draw from.