The compromise was wrested with forceps: the Biden administration announced on Monday, May 22, a “historic” agreement with seven states in the American West to reduce their consumption of water drawn from the Colorado River, threatened by more than twenty years of drought aggravated by global warming.

This plan, announced after a year of tense negotiations, offers a reprieve for this major river, which originates in the Rocky Mountains and empties into the Sea of ??Cortez in Mexico. The river supplies about 40 million people with water and irrigates millions of acres of arable land, but in recent years its flow has dropped by about a third: its level was so low that the American West was at risk of disaster.

The agreement plans to save 3.7 billion cubic meters of water by 2026, according to the statement from the Interior Ministry. At this date, further reductions will be necessary. California, Nevada and Arizona have agreed to reduce their water consumption from the river by 13%. Three-quarters of this volume will be offset by the federal government, which will provide $1.2 billion to help farmers and cities consume less, according to US media. The remaining quarter will have to be saved without compensation.

Interior Minister Deb Haaland hailed the Biden administration’s “commitment” to “finding consensus solutions in the face of climate change and persistent drought.” “The entire western United States is on the front lines of climate change. We must work together to face this crisis,” California Governor Gavin Newsom said in a statement.

Model in crisis

This consensual tone masks the very real tensions around the river. The Colorado watershed is regulated by a historically biased 1922 treaty: overconsumption was inevitable due to the erroneous estimate of the average river flow taken as the basis. This treaty is based on the “first come, first served” rule. California farmers can draw more water from the river than Arizona and Nevada combined.

The shortcomings of this model came to light last year. After twenty years of drought, the two largest reservoirs in the American West, Lake Powell and Lake Mead, have reached historic lows. The situation was so critical that the authorities feared that their level would fall below that of the hydroelectric turbines of the dams, which would have interrupted the production of electricity and prevented the river from flowing downstream.

Faced with this crisis, the federal government first asked the seven bordering states – Wyoming, Utah, Colorado, New Mexico, California, Nevada and Arizona – to agree to reduce their consumption by a quarter, but the negotiations got bogged down and the deadlines set for finding a compromise were postponed several times. The talks turned into a confrontation between California, the most advantaged by the system, and the six other states, which asked it to do the majority of the efforts.

To break the deadlock, Washington threatened in April to cut to the chase: The Biden administration has publicly considered imposing cuts evenly on California, Nevada, and Arizona. This proposal would have completely upset the law in force for a century and probably caused a long legal battle.

The exceptionally rainy winter in the region has helped to ease tensions: the cuts announced are ultimately less ambitious than expected, as the flow of the river has increased. But scientists are already warning that this respite could only be short-lived. “We now have a prospect for raising the level of our reservoirs in the short term,” said Katie Hobbs, Governor of Arizona.