80 years ago, the United States and Mexico agreed to share the waters of the two major rivers that flow through both countries: the Rio Grande and the Colorado. The treaty was signed when water was not as scarce as it is today.

Water from Mexico flows to Texas’s half-billion-dollar citrus industry and dozens of cities near the border. On the Mexican side, some border states such as Baja California and Chihuahua rely heavily on water coming from the American side of the Colorado River.

Now these water distribution systems are facing one of the biggest challenges in their history. Mexico is about 265 billion gallons behind on its water deliveries to the United States.

Unpredictable weather patterns due to climate change, growing populations, aging infrastructure and significant water waste have led to water shortages in both countries and escalated tensions along the border.

Maria-Elena Giner is the U.S. commissioner of the International Boundary and Water Commission, the binational agency that oversees and resolves disputes under the 1944 water treaty.

Mexico is “at the lowest level ever” in the contract’s history, Giner said. The contract runs in five-year cycles, and the current deadline for deliveries is not until October 2025.

But “the problem is that they are so far behind that it will be very difficult, if not statistically impossible, for them to make up that gap,” Giner said.

Victor Magaña Rueda, an environmental scientist at the National Autonomous University of Mexico, said no country could survive without the water of another, describing the 1944 treaty as a first step.

“Now we probably need to think about how we manage water and how both sides adapt to the changes we are experiencing in terms of climate,” Rueda said.

Tensions in the US are increasing

State lawmakers say the last sugar mill in Texas closed earlier this year due to water shortages, and officials don’t want the same thing to happen to the state’s citrus industry, which is concentrated in the lower Rio Grande Valley, and other agricultural businesses that rely on Mexican water.

Ten members of a bipartisan congressional delegation called on the U.S. Congress to withhold funding and aid to Mexico – with the exception of funds for border control – until the country delivers the water it needs.

“Farmers and ranchers across South Texas continue to face financial pressures and could suffer a similar fate to the sugar industry if Mexico continues to withhold water,” the lawmakers wrote in May. “In addition, the lack of reliable water supplies impacts communities and threatens the quality of life for many American citizens living along our border.”

Texas Rep. Henry Cuellar signed the letter, saying it was not the first time he had seen Mexico fall behind on water deliveries.

But the unpredictability of this cycle has brought considerable hardship to members of his congressional district in southwest Texas along the Rio Grande.

“Mexico hasn’t even responded to this, which to me means one thing,” Cuellar said of the letter last month. “It means that the potential loss of money is probably less important to their communities right now than the water. Their silence shows that they are more interested in water than money right now.”

Texas Republican Monica de la Cruz, another Texas House member who signed the letter, spoke before Congress in May to highlight the loss of agriculture and industry in South Texas.

“If we can’t save our farmers, then Mexico doesn’t deserve to have money given to them,” the Republican said. “We want our water – we demand our water.”

While Congress has not yet allocated funds to the government for the next fiscal year, which begins in October, and could therefore consider an interim bill to avert a shutdown, the risk of financial losses for Mexico is rather theoretical at this point.

As urgent as the water supply from Mexico may seem, it is not the only water problem in Texas. In Texas and several other states in the US, a significant amount of water is wasted due to infrastructure breaks and leaks.

The state lost an estimated 129 billion gallons of water in 2022, the latest figures available from water loss audit data submitted by public water utilities to the Texas Water Development Board.

Water policy in Mexico

To address Texas’ water shortage, state officials last year proposed a solution: a “minute,” or contract amendment, that would allow Mexico to pay for water supplies directly to South Texas, rather than initially giving two-thirds to the Mexican state of Tamaulipas, as the contract currently requires.

But satisfying hunger in South Texas in front of its own citizens was probably a hopeless undertaking given this year’s presidential elections in Mexico.

Negotiations on the treaty changes have been completed and both countries were supposed to sign the treaty in December last year. However, Mexico has not yet received official approval, said Giner of the International Boundary and Water Commission.

Several Mexican officials contacted for this article declined to comment officially on Mexico’s water shipments to Texas and future contract negotiations.

But on the Mexican side of the border, the country is grappling with its own water problems in addition to water disputes with the United States. A crisis in Mexico City this year left many of its 22 million residents without clean water as the city braced for the possibility of a water shortage.

These pressures, coupled with a rapidly growing population, have caused the country to fall significantly behind in its water deliveries to the United States.

In April, Mexico’s current president, Andrés Manuel López Obrador, said the country would focus on ensuring water supplies for its population.

“Priority must be given to domestic water, which is used by people and not by companies,” he said. “We are looking for a solution to the problem of drought and water scarcity – we are working on that.”

New President-elect Claudia Sheinbaum is expected to take a similar approach when she takes office in October, said Rueda, an environmental scientist.

Problems before the last election

This five-year cycle is not the first time that Mexico has fallen behind in supplying water to the United States.

Towards the end of the last cycle, which ended just days before the 2020 U.S. presidential election, Mexico had supplied most, but not all, of its water to the United States.

Mexico tried unsuccessfully to take water from a dam in the state of Chihuahua. Three days before the official deadline, Mexico and the United States reached an agreement that allowed Mexico to transfer water from the Amistad and Falcon reservoirs along the border to the United States to avoid a shortage.

However, the diversion of the reservoir water has nearly depleted northern Mexico’s entire water reserves, making the country even more vulnerable to future disruptions.

In the event that Mexico is unable to supply its entire water supply in the current cycle, the agreement provides for the transfer of a water debt for one cycle.

So if Mexico does not catch up by the end of this cycle, it can pay off its debt until the end of the next cycle. Minute 234 stipulates that no country can accumulate a deficit in two consecutive five-year cycles.

Mexican environmental scientist Rueda said some farmers in Mexico wanted to terminate the contract with the United States because they needed the water for their crops.

However, this would have devastating consequences for the population of both countries as a whole.

“If we terminate the agreement, it will be a real disaster for the region, just because of the selfishness of a few,” he said.

Copyright: NPR