This week, Arizona, California, and Nevada reached a breakthrough agreement to reduce their water consumption from the drought-troubled Colorado River. Assuming all the river basin states and the federal government approve the deal, the next step would likely involve negotiations with Mexico, considering the substantial impacts the deal could have on the country.
Spanning 1,450 miles and ending in Mexico, the river provides drinking water for over 40 million people in the U.S. and Mexico and drives a $1.4 trillion economy on the U.S. side. The river is subject to a handful of treaties, some of which address the Colorado River dispute, a long-running quarrel between the U.S. and Mexico over water rights.
But in recent years, the countries’ relationship, when it comes to the river at least, has entered a new era of agreement and mutual advancement, as both countries face unprecedented drought and a need to revamp water systems.
“On earlier occasions, what I’ve seen is two countries that had a bilateral water management agreement where the gains from one country would equal the losses of the other country,” Carlos de la Parra, who leads Restauremos El Colorado, an environmental nonprofit, tells TIME. “They’ve migrated into a regional approach, realizing that it’s the same river, it’s the same basin and investments on one side of the border will benefit both sides of the border.”
Read more: The Colorado River Drought Is a Cautionary Climate Tale
A century ago, the river was a thriving wetland, navigable by large boats. Today, with typically less snowpack in the Rocky Mountains feeding the river and rising temperatures linked to climate change contributing to evaporation, drought conditions have skyrocketed over the past 20 years. Increased water use in the face of rapid development across urban centers in the region has also exacerbated the strain.
Negotiations across the border
In the U.S., seven states rely on the Colorado River basin as a major water source. Divided into two regions, Colorado, New Mexico, Utah, and Wyoming form the upper basin. California, Arizona, and Nevada compromise the lower basin. The water diverted to Mexico is primarily for the Mexicali Valley and the cities of Mexicali, Tecate, and Tijuana.
Under a 1944 treaty established between the U.S. and Mexican governments, Mexico was allotted a guaranteed annual quantity of water. The agreement had flaws though. It didn’t mention water quality, and in the 1960s when the river’s salinity rose dramatically, the water directed to Mexico was too salty for human consumption or agriculture. Following farmer protests and threats from the Mexican government to take the dispute to the International Court of Justice, the U.S. agreed to an updated treaty in 1973 that ensured equal water quality.
Most recently in 2017, the two governments revisited the negotiating table to strike Minute 323, a nine-year deal that set standards for how water should be allocated during surpluses and reduced during droughts. It also committed both countries to pledge resources and funding for environmental restoration.
John Shepard, senior advisor at the Sonoran Institute, a non-profit that advocates for Colorado River restoration, notes that a new deal could be on the horizon. “If the lower basins agreed to cuts as they’re being articulated in this agreement, then Mexico will likely agree to a proportional share of cuts.”
Details behind the lower basin’s proposal remain unclear, but Shepard believes the plan could definitely impact Mexico’s water supply, for better or worse. As water moves down the river and through dams to Mexico, the quantity and salinity can change, depending on the basin states’ habits, hence the need for more analysis and cross-border discussion, he says.
For example, “if there are any cuts related to some of the agricultural districts in Arizona that provide return flows [water traveling downstream], then those could potentially impact the Cienega de Santa Clara [wetlands in Mexico],” he says.
An opportunity for sustainability
Keeping the river and its ecosystems healthy has been a source of argument over the years. In the U.S. the prevailing view has been that it’s Mexico’s responsibility to protect and restore the delta because it’s chiefly located in Mexico, where it then flows into the Gulf of California. Mexico has argued that the U.S. should take responsibility because the country’s management and control of the river caused poor water quality and decimated habitats.
Now, experts on both sides of the border are working to find a more collaborative way forward.
“There’s a saying that, ‘a crisis is a terrible thing to waste.’ In many ways, that’s how I’m approaching this,” De la Parra says. “Many people like myself are hard at work, thinking about how we can capitalize the crisis and move the irrigation district and other water uses into a more productive, more sustainable model.”
Read more: How to Save the Colorado River and the American West
Communities reliant on the Colorado River in both the U.S. and Mexico face a similar challenge: Around 80% of their water consumption goes towards agriculture, and half of the basin’s water is used to grow feed for livestock. Reducing dependency on the river largely depends on transforming the agriculture industry.
“For an irrigation district that has always relied on deliveries from the United States, now that the shortages are coming, they’re hard pressed to learn how to manage an agricultural industry that is more modern and resilient,” De la Parra says. Researchers have suggested switching to less water intensive crops and upgrading sustainable farming practices.
A need for funds
Under the U.S. lower basin deal announced this week, by agreeing to water cuts, districts across the region would qualify for federal grants reaching about $1.2 billion. The grants are part of the Inflation Reduction Act, which pledged billions of dollars last year to climate resilience and upgrading water infrastructure.
De la Parra points out that if Mexico cuts its water consumption from the river too, affected communities would also need some sort of compensation plan. “[Cuts] are going to have to come with additional investment, either from the Mexican federal government, the state government, private entities, or the U.S. via an agreement with Mexico,” he says.
But De la Parra is hopeful of the river’s future. A decade ago, he says, it would’ve been unfathomable to see this scope of international investments, shared water infrastructure, and both countries jointly working to restore the delta.
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