Flooding Along the Fence: Hydrological Impacts Along the Rio Grande at Eagle Pass, Texas

Background

In addition to allowing fence construction, the Real ID Act of 2005 and Secure Fence Act of 2006 allowed the Secretary of Homeland Security to waive all environmental laws that could have held up fence construction in proposed locations (NBW, 2014; Nunez-Neto & Garcia, 2007). As a result, the federal government did not conduct a comprehensive study of the hydrologic impact of the fence prior to fence construction. Local accounts within these communities suggest that the fence may be exacerbating flooding, diverting floodwaters, and stalling recessional flood flows.

Changes in the hydrologic regime of the river brought on by the fence have the potential to disrupt geomorphic processes along the border. For example, although not along the Rio Grande, Organ Pipe Cactus National Monument in Arizona received monsoonal rains in 2008. Washes that normally cross the fence were flooded and debris piled up in the grates meant to allow water to flow through the fence. The fence and water flows quickly created dams filled with debris, sediment, and water and the area underwent millions of dollars of damage (McCombs, 2011). Residents described a similar situation in Eagle Pass, Texas when large floods hit the area in 2010, 2013, and 2014. Locals said that the river rose above the fence and when the floodwaters began receding, debris trapped behind the fence acted like a dam, causing areas in the city to be inundated with water longer than they would have without the presence of the fence (Cantu, personal communication).