From 2017 through January 2021, federal agencies built about 450 miles of barriers along the U.S. Southwest border. To expedite construction, they waived federal environmental and other laws.
The construction harmed some cultural and natural resources, for example, by blasting at a tribal burial site, altering water flows, and preventing access for endangered species. For example, the barrier system itself can disrupt the natural flow of water in heavy rain events. These rain events can occur regularly along rivers and drainages near the border, and barrier-related obstructions can exacerbate flooding, according to National Park Service and Bureau of Land Management officials. A culturally important site in Arizona was irreparably damaged when contractors used explosives to clear the way for expanding an existing patrol road. The blasting damaged portions of Monument Hill, a site that the Hia-C’ed O’odham, ancestors of the Tohono O’odham, and other Tribes historically used for religious ceremonies and that remains important to several Indigenous communities. In addition, tribal and agency officials and stakeholders have reported that installation of pedestrian barriers has affected wildlife by impeding their movement across the landscape, including in habitat for threatened and endangered species. Although some pedestrian barriers were designed to have small openings at the base to accommodate passage for small animals, bigger animals—such as the Sonoran pronghorn and wolves— are too large to pass through these openings.
Before building, the Department of Homeland Security (DHS) assessed some potential effects of the construction. But federal officials and stakeholders have told the Government Accountability Office (GAO) that they didn’t get enough information from DHS to give meaningful input.
DHS’s U.S. Customs and Border Protection (CBP) and the Department of Defense (DOD) installed about 458 miles of border barrier panels across the southwest border from January 2017 through January 2021. Most (81 percent) of the miles of panels replaced existing barriers. The agencies installed over 62 percent of barrier miles on federal lands, including on those managed by the Department of the Interior. Interior and CBP officials, as well as federally recognized Tribes and stakeholders, noted that the barriers led to various impacts, including to cultural resources, water sources, and endangered species, and from erosion.
Since the administration paused border barrier construction in January 2021, CBP has prioritized efforts to address safety hazards left at incomplete project sites, such as removing exposed rebar. In addition, CBP and Interior have worked together to identify actions to mitigate the impacts on federal lands. As the agencies are both involved in addressing these impacts, GAO says they could benefit from clearly defining their roles and responsibilities for doing so and jointly identifying the costs and time frames to complete all of the identified mitigation actions, consistent with collaboration leading practices. The government watchdog believes that documenting a joint strategy that includes these inputs could help CBP and Interior better ensure that key resource impacts of border barrier construction are mitigated and that decision makers have the information needed to allocate resources.
Before proceeding with barrier construction from 2017 to 2021, CBP took steps to assess the potential impacts of such construction, while relying on waivers of cultural and natural resource-related laws to expedite construction. For example, CBP solicited input from land management agencies, Tribes, and the public. Interior and tribal officials and stakeholders told GAO however that CBP’s information was not sufficiently detailed to facilitate meaningful input. They provided suggestions to GAO for improving CBP’s assessments.
GAO found that CBP has not evaluated lessons learned from its assessments, and says doing so could help the agency better identify potential impacts of any future projects. CBP officials said they have not evaluated lessons learned regarding their assessments because they have not completed the barrier construction projects. They said that they would typically wait to consider such lessons once that occurs. However, GAO pointed out that CBP conducted its efforts to assess the potential impacts of those projects prior to January 2021, which would allow it to consider any lessons from those efforts now, even if it is conducting additional work at the project sites.
GAO is making three recommendations, including that CBP and Interior document a joint strategy to mitigate resource impacts from barrier construction and that CBP evaluate lessons learned from its assessments of potential cultural and natural resource impacts. The agencies agreed with these recommendations and expect to meet them by August 2024.
