At risk: Officials must address Amistad Dam integrity

One of the first major issues the Rio GrandeValley’s new congressional delegation should address is the condition of the Amistad dam.

The dam, connecting Del Rio, Texas, and Ciudad Acuña, Mexico, is the primary water-control structure for the lower part of the Rio Grande, including the Rio GrandeValley. Falcon Dam lies between here and there, but Amistad has a greater capacity. It is deeper and has less surface area, which means less water will evaporate. For this reason water conservation officials with the International Boundary and Water Commission and the Texas Commission on Environmental Quality Watermaster’s Office keep as much water as possible at Amistad, especially in light of dry conditions that have plagued South Texas for the past few decades. For example, on Dec. 1 Amistad water levels were at 46.7% of the reservoir’s capacity while Falcon held only 14.4% of its lower capacity.

The Army Corps of Engineers has given the 53-year-old structure a Class II rating, the second-most-critical on its priority list. The rating means its condition is of “urgent” concern regarding structural safety, as its risk of failure is “too high to assure public safety.”

Low water levels caused by the drought in 1994 revealed that the limestone base upon which the dam was built is deteriorating and forming sinkholes beneath the concrete. If the deterioration causes the dam to fail, the rush of water and rising river levels could affect up to 400,000 people directly — in addition to millions more who would be affected indirectly from the loss of trade, irrigation water and municipal water supplies.

FalconLake, even at capacity, couldn’t handle the ensuing conditions alone.

Determining and executing a mitigation plan will take a lot of people, a lot of time and a lot of money, and the sooner the process begins the better.

For this reason, South Texas members of Congress — both Democrats and Republican — need to combine their efforts to raise awareness among their colleagues to the urgency of the situation. It likely would be easier to secure steady, moderate levels of funding for repairs and contingency measures, such as reinforcing levees and possibly mapping out a possible floodway, rather than a large emergency allocation if inaction now leads to further deterioration and even greater repair.

As the dam is jointly owned by the United States and Mexico, our southern neighbors need to do their part. International negotiations can take time and the earliest possible start can help officials and engineers on both sides coordinate their efforts.

Former President Trump and current President Biden both have made our nation’s infrastructure a priority, so members of Congress from both sides of the aisle should be willing to give the integrity of our nation’s 12th-largest reservoir the attention it needs. A unified front from our border lawmakers can help ensure that they appreciate the possible crisis that is growing as the dam’s base continues to erode, and take immediate action to prevent the largest water-control structure on the Rio Grande from failing and becoming a dam shame.