According to an 80-year-old treaty, the USA and Mexico share the water resources of the Colorado and Rio Grande Rivers. However, due to severe drought and high temperatures, Mexico has been unable to meet its water delivery commitments, raising concerns about its ability to uphold its obligations.
Some Mexican politicians argue that they cannot provide what they do not have.
This situation is particularly challenging for farmers in South Texas, who are also suffering from water shortages due to lack of rainfall. They claim that the shortage of water from Mexico is exacerbating a crisis and threatening the future of agriculture in the region. Texas leaders have urged the Biden administration to link aid to Mexico with resolving its water deficit.
Both nations are preparing for another long and hot summer, hoping that storms might replenish the rivers affected by drought in Mexico. However, experts caution against relying solely on short-term solutions like rain dances, given the long-term nature of the problem.

According to a treaty established in 1944, Mexico is obligated to deliver 2.15 billion cubic meters of water from the Rio Grande to the USA every five years. In return, the USA must supply Mexico with 1.85 billion cubic meters of water from the Colorado River annually.
Currently, Mexico is significantly lagging behind in its commitments, as noted by Maria Elena Giner, the U.S. Commissioner of the International Boundary and Water Commission, which oversees the bilateral treaty.
The Rio Grande, known as the Río Bravo in Mexico, is one of North America’s largest rivers, stretching about three thousand kilometers from the Rocky Mountains in Colorado through three U.S. states and five Mexican states to the Gulf of Mexico.
Years of excessive use to support growing farmlands and populations, combined with rising temperatures and droughts due to climate change, are now taking their toll.
Maria Elena Giner, U.S. Commissioner of the International Boundary and Water Commission, explains that the unpredictability of the river is why Mexico’s obligations are based on five-year cycles rather than annually. “There will always be times of deficit and surplus,” she commented.
Several factors contribute to this crisis. Water demand has risen with development along the Rio Grande. The implementation of the North American Free Trade Agreement (NAFTA) in 1994 led to a significant increase in farms and factories in Mexico, many of which produce for U.S. and Canadian markets. Both sides of the border have experienced urbanization and population growth.
Simultaneously, the frequency and intensity of droughts and heatwaves have increased due to climate change. “There are treaties for a stable climate, which are now being applied in an unstable climate,” noted Rueda.
The situation is critical for both countries. Mexican water is stored in the Falcon and Amistad reservoirs, which supply homes and rural areas, but these reservoirs are operating at historically low levels: by mid-June, Amistad was less than 26% of its capacity and Falcon only 9.9%.
Brian Jones, a farmer in the Rio Grande Valley in Texas, warned that farmers are experiencing acute or existing water shortages. He grows irrigated cotton, corn, sorghum, and soybeans in Hidalgo County, Texas, and is a member of the Texas Farm Bureau.
The reduced water deliveries from Mexico, coupled with the lack of rain in the region, represent a significant threat to the state’s citrus sector, Jones said. But even worse is the situation for the sugar industry. “The sugar industry is going away in Texas and will never come back,” he lamented.
However, water scarcity is not only affecting one side of the border. Mexico is facing its most extensive and severe drought since 2011, affecting almost 90% of the country. The water issue has become increasingly urgent, with concerns that several cities, including Mexico City, may be approaching a “Day Zero,” when no water will flow from the taps.
The situation in northern Mexico is particularly dire. Victor Magaña Rueda, a climatologist at the National Autonomous University of Mexico, emphasized that the effects are evident in the alarmingly low levels of reservoirs and even groundwater in the region.
Since February, the entire state of Chihuahua has been suffering from drought, with data until the end of May showing that almost 40% of the state is experiencing “exceptional drought,” the most severe classification. Salvador Alcántar, a legislator in Chihuahua, reported that no rain has fallen for over eight months. He stressed that climate change is a permanent reality and it is crucial to learn how to deal with its consequences. River and groundwater levels are dropping rapidly, and farmers have been struggling with issues for years, as Alcántar explained.
Tensions in the region peaked in 2020 when the Mexican government decided to release water from one of Chihuahua’s reservoirs to meet its water delivery commitments. This triggered severe protests among farmers and culminated in a tragic incident where a woman was shot by the National Guard.
Chihuahua faces new challenges. Mexican legislator Alcántar expressed concern about the water shortage and realistically questioned how they could meet the treaty’s obligations if no water is available. He emphasized that no one can be forced to deliver something they do not have.
A complete renegotiation of the treaty is unlikely. Instead, changes are typically made through agreed-upon protocols between the countries. These protocols can range from data sharing to adjustments in water deliveries.
Discussions about a new protocol to ensure more reliable water deliveries from Mexico stalled at the end of last year while Mexico focused on its elections. With climate scientist Claudia Sheinbaum as president since October, negotiations are back on the table, according to Maria Elena Giner, the U.S. Commissioner of the International Boundary and Water Commission. Giner stated that Mexico has been asked to present a clear plan on how it will handle its current water deficit.
This situation highlights a complex conflict with no clear winners, where the management and sharing of water resources are crucial for the economic development and sustainability of both countries, but also sources of tension and disputes.
The hope for alleviating the water scarcity lies in events such as tropical storms or active hurricane seasons, but predicting when and where these storms will occur and how much rain they will bring is extremely difficult. Relying solely on these natural events would leave Mexico entirely at the mercy of nature regarding its water future, as Magnaña Rueda from UNAM emphasized.
In the short term, Maria Elena Giner acknowledges that there are not many options without available water for distribution. However, she remains optimistic and advocates for tools to improve drought resilience, water conservation, and efficiency.
Claudia Sheinbaum, the newly elected president, has committed to prioritizing the water issue in Mexico. But political changes in the USA could also influence the dynamics of bilateral cooperation when the current five-year cycle ends in 2025.
Vianey Rueda, an expert on the treaty at the University of Michigan, emphasizes the need for water agreements to adapt to a constantly changing climate. Instead of viewing water as a zero-sum game, where one party’s gain implies another’s loss, both sides should recognize that they face similar challenges due to climate change. “We need to stop playing this game and recognize that we both lose. No one wins,” Rueda commented.
This approach reflects the complexity of water management in the context of global climate changes, where cooperation and adaptation are crucial to addressing shared challenges of water scarcity and ensuring long-term sustainability for both countries.