Mexico Keeps Water Dispute Out of USMCA Renegotiation

Mexico's rejection of incorporating 1944 Water Treaty compliance into the USMCA review signals that the Sheinbaum administration is managing the dispute as a bilateral technical matter rather than a trade issue, limiting its scope amid the ongoing USMCA renegotiation. With Mexico having delivered only 28% of its five-year water obligation and a technical agreement now setting a minimum annual delivery of 432 million m3, agricultural producers, irrigation districts, and water-intensive industries in border states face continued operational uncertainty tied to drought conditions and cross-border water governance.

Mexican President Claudia Sheinbaum rejected that her government has faced pressure from the United States to incorporate water delivery compliance into the formal USMCA review, following a request by Republican Sen. John Cornyn of Texas to do so.

"Well, if there is an agreement, I do not know why (they would ask to include it in the treaty review). Maybe the senator is not aware of it," Sheinbaum said.

Cornyn made the request through a letter sent in February to US Trade Representative Jamieson Greer, asking that Mexico's compliance with the 1944 Water Treaty be addressed within the USMCA review process, currently underway.

Sheinbaum said the two countries have already reached a technical agreement to address Mexico's water delivery shortfall, making the legislative push unnecessary. She described the current stage as a matter of logistics rather than politics. The technical agreement, announced jointly by US Secretary of State Marco Rubio and Secretary of Agriculture Brooke Rollins, establishes a minimum delivery of 432 million m3/y of water and incorporates infrastructure planning and long-term adaptation measures for the Rio Bravo basin.

Water Legal Framework

Under the 1944 Water Treaty, the legal framework governing water allocations from the Tijuana, Colorado and Bravo rivers, from Fort Quitman, Texas, to the Gulf of Mexico, Mexico is required to deliver 2,158 million m3 of water to the United States over five-year cycles. In exchange, the United States delivers water from the Colorado River. Mexico receives two-thirds of the Rio Bravo's flow and its tributaries, while the United States is entitled to one-third.

Mexico is currently more than three years into the current cycle and has delivered approximately 28% of its obligation, according to treaty data. Both governments have signed an annex allowing Mexico to regularize deliveries in the next cycle based on actual water availability. Officials on both sides have reaffirmed that the treaty remains in force.

Sheinbaum attributed Mexico's shortfall to prolonged drought rather than noncompliance. "In the last five years Mexico could not deliver the amount of water, not because it did not want to, but because those were years of severe drought. So, there were no conditions to deliver the water," she said. The treaty, she noted, explicitly allows for delayed deliveries during drought cycles, provided volumes are replenished in subsequent years.

"We agreed on a water delivery given that there is a shortfall from the previous five years, in line with the amount of water that exists, because you cannot deliver water that we do not have or affect human water consumption in our country or agricultural irrigation," Sheinbaum said. She added that her government maintains ongoing communication with the governors of Tamaulipas, Nuevo Leon, Chihuahua and Coahuila, border states that could be affected by delivery volumes.

Tensions over the issue escalated in December 2025, when President Donald Trump accused Mexico of failing to meet its treaty obligations and linked water deliveries to broader trade disputes. Trump threatened a 5% tariff if Mexico failed to deliver 200,000 acre-feet of water by Dec. 31 and later publicly claimed Mexico owed Texas 1.3 million acre-feet. Emergency technical and diplomatic meetings began Dec. 9 to address US demands.

Experts cautioned that the conflict extends beyond the treaty itself. Eduardo Vázquez, Director, Agua Capital, and Raúl Rodríguez Márquez, President, Water Advisory Council, cited delayed deliveries, underused infrastructure, prolonged drought, and weaker institutional capacity as underlying structural challenges. Vázquez suggested the water issue was being used as leverage in broader negotiations. "Maybe it is not even really about the treat y… It is probably commercial issues. But Trump has it at hand, and can use it," he said.

Progress in bilateral talks was reported in April 2025, when Mexican Agriculture Minister Julio Berdegué, Rollins and US Undersecretary of State Chris Landau held discussions on 2025 deliveries and plans to modernize irrigation systems in districts 014 in Baja California; 005 and 009 in Chihuahua; and 025 and 026 in Tamaulipas. "We will continue working together for the benefit of both countries," Berdegué said. Rollins acknowledged progress but noted that US farmers are still awaiting relief. "American agriculture has been asking for this relief for years and has not received it," she said.

To address longer-term water efficiency, Mexico launched the National Irrigation Modernization Program, which aims to upgrade systems across more than 200,000ha, benefiting at least 225,000 farmers across 18 irrigation districts in 13 states, including Sonora, Chihuahua, Coahuila, Durango, Sinaloa and Tamaulipas, among others. The program seeks to raise agricultural output while reducing water use, freeing resources for aquifer recharge and urban consumption in water-stressed regions near the Rio Bravo. Six projects are currently under execution, while 10 others are in the bidding process.