Texas Reservoirs Face Unprecedented Water Levels Amid Ongoing Drought

Two of Texas's most important reservoirs are seeing lower water levels than ever before. The Falcon International Reservoir and the Amistad International Reservoir, situated along the Texas-Mexico border, have been experiencing significant decreases in water levels in recent months. These alarming trends are bringing them closer to their lowest-ever recorded levels, a situation that has raised concerns among local residents and officials alike.

As of August 7, the Amistad Reservoir is only 25.2 percent full, with a water level of 1,048.77 feet above sea level, while the Falcon Reservoir is even lower at just 13.3 percent full, measuring 255.51 feet above sea level. Notably, this time last year, these reservoirs were significantly fuller, with Amistad at 1,066.54 feet and Falcon at 259.28 feet. The Amistad Reservoir even reached a record-low of 1,047.15 feet on July 17 this year, surpassing its previous record of 1,052.48 feet from August 2022.

These reservoirs, which were built for flood control, water storage, and hydroelectric power, are results of collaborative efforts between the United States and Mexico. The Amistad Dam and Falcon Dam were established under a 1944 treaty that outlined the water contributions from both countries. However, the ongoing drought conditions, which have been affecting the region for years, are now exacerbating the water shortages.

In recent reports, both the U.S. and Mexico are obligated to contribute water to these reservoirs. Interestingly, while Mexico is behind on its water contributions, both reservoirs are receiving considerably less water from the U.S. than they did during the 1980s. Between 2011 and 2020, the Amistad Reservoir saw a staggering 33 percent reduction in water flow compared to the 1980s, accounting for approximately 4.6 million acre-feet less water. Meanwhile, the Falcon Reservoir recorded a 21.5 percent decrease during the same timeframe.

This decline in water flow can be attributed to the ongoing megadrought that has been affecting the U.S. Southwest for decades. Not only are these reservoirs impacted, but others like Lake Mead and Lake Powell are also experiencing severe reductions in water levels. Experts note that the current drought began around the turn of the century and has been consistently worsening, with minimal rainfall providing only fleeting relief.

According to Hannah Cloke, a professor of hydrology at the University of Reading, this megadrought is unique in its longevity compared to previous droughts that have occurred in this region. While heavy rainfall can temporarily refill reservoirs, the prevailing drought conditions often lead to rapid evaporation and depletion. The consequences of severe drought can be detrimental to agricultural ecosystems and water supplies, leading to reduced productivity and diminished groundwater resources essential for fresh water in cities and towns.

Climate change is expected to further exacerbate these challenges, increasing temperatures and altering rainfall patterns across the Southwest. Antonia Hadjimichael, an assistant professor in geosciences at Penn State University, indicates that rising temperatures—driven by human-caused climate change—are a significant factor in the reduced water flow observed today. Unlike previous droughts, which were primarily due to lack of precipitation, the current scenario is compounded by increasingly high temperatures.

Moreover, under the 1944 treaty, Mexico is expected to contribute 1,750,000 acre-feet of water from its Rio Grande tributaries every five years. However, they are currently about 900,000 acre-feet behind and have until October 2025 to fulfill this obligation.

The diminishing water levels in both the Falcon and Amistad reservoirs may necessitate local water suppliers to explore alternative sources. IBWC Commissioner Maria Elena Giner has emphasized the need for strategic planning to enhance drought resilience within the region. As the situation evolves, it remains critical for stakeholders to address these challenges effectively.

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