Big Bend Border Facts

What We Know – What Federal Reports Confirm – Why It Matters Here

WHAT IS BEING PROPOSED IN THE BIG BEND?

According to DHS Federal Register postings and reporting:

Construction authority has been activated for ~175 miles of the Rio Grande corridor in the Big Bend region, including through Big Bend Ranch State Park and Big Bend National Park.

DHS is waiving 28 federal laws, including:

National Environmental Policy Act (NEPA)
National Historic Preservation Act (NHPA)
Native American Graves Protection and Repatriation Act (NAGPRA)
Wild and Scenic Rivers Act (WSRA)

The mapped footprint includes border wall sections through:

Rio Grande Village
Hot Springs Historic District
Cottonwood Campground
Santa Elena Canyon Overlook
Big Bend Ranch State Park river corridor
The La Junta Archeological District around Presidio and Redford

WHAT DO FEDERAL OVERSIGHT REPORTS CONFIRM ABOUT THE IMPACT?

The Government Accountability Office (GAO) found that border walls constructed between 2017–2021:

Caused damage to cultural sites, including tribal burials.
Disrupted wildlife movement and endangered species habitat.
Altered natural water flow and contributed to flooding.
Damaged artesian wells and groundwater systems.
Waived environmental and historic preservation laws.

GAO concluded:

Impacts were significant.
Agencies did not adequately evaluate lessons learned.
Mitigation responsibilities remain unclear.

The Federal Governments own accounting indicates border walls cause significant harm.

FLOODING AS DOCUMENTED RISK

Multiple case studies demonstrate fence-induced flooding:

Organ Pipe Cactus National Monument (AZ)
Storm debris accumulated against fencing, creating a dam.
Floodwaters surged to 7 feet deep.
Foundations were scoured and damaged.

Nogales, AZ / Sonora (2008)

Border infrastructure blocked storm channels.
Floodwaters backed up.
Mexico declared a disaster zone.

Rio Grande Floodplain (Texas)

Independent hydrologists and IBWC engineers repeatedly warned that bollard walls in floodplains increase obstruction risk.

The Rio Grande in the Big Bend is characterized by:

Monsoonal surges
Debris-heavy flash flooding
Dynamic sediment transport
Treaty obligations under the 1970 Boundary Treaty

The Rio Grande floodplain is not appropriate for rigid obstruction.

HOW WILL THIS AFFECT WILDLIFE & ECOLOGY?

Big Bend is:

An International Dark Sky Reserve
A climate refugium
A north-south wildlife corridor
Habitat for black bear, mountain lion, and threatened and endangered species.
The most intact Chihuahuan Desert ecosystem in the United States.

A 2024 study published in Frontiers in Ecology and Evolution (100-mile camera study in AZ) found:

Only 9% of wildlife interactions with steel bollard wall resulted in successful crossing.
That is an 86% reduction compared to vehicle barriers.
0% crossing success for deer, black bear, mountain lion, and turkey.

This is the first quantitative large-mammal crossing dataset of its kind.

Pollinators and Lighting

Recent USGS research in South Texas found:

7% of butterflies altered course.
20% of moths failed to cross.

Artificial lighting:

Disrupts nocturnal species
Affects bats (primary pollinators of agave and cacti)
Alters predator-prey behavior

Border infrastructure is not just vertical steel — it includes:

Cleared corridors
Access roads
Stadium lighting
Surveillance towers
Habitat loss extends beyond the footprint of the wall.

CULTURAL RESOURCES AND LAW WAIVERS

The current Big Bend waiver suspends protections under laws that normally require:

Archaeological survey
Tribal consultation
Environmental impact statements
Public comment

GAO documented blasting damage to Monument Hill (Tohono O’odham sacred site) under prior waivers. Road and wall construction would destroy untold numbers of archeological sites, most of which have never been documented.

Big Bend contains:

Thousands of prehistoric archeological sites
Historic ranching settlements
Cross-border cultural landscapes
Wild and Scenic River corridors
Waiver authority removes mandatory review processes.

EFFECTIVENESS & ECONOMIC IMPACT

Research on prior fence expansion (Secure Fence Act era) found:

Fencing reduced migration modestly.
U.S. GDP declined due to reduced labor participation.
Cost per migrant prevented estimated at ~$30,000 in lost output.
Fence repair costs averaged $784 per breach (GAO-18-397T).
Replacement costs averaged $4.84 million per mile (2011–2016 data).
Maintenance is ongoing and expensive.

Big Bend’s economy relies heavily on:

Tourism
Ecotourism
River recreation
Dark sky tourism
International visitation
Fragmentation affects recreation access and landscape value.

BIG BEND IS A HISTORICALLY LOW CROSSING SECTOR

CBP December 2025 data (as reported):

Big Bend Sector: 178 apprehensions
Rio Grande Valley: 1,371 apprehensions (same month)

The Big Bend sector has historically been:

Largest by geography
Lowest by crossing volume

Infrastructure decisions should reflect geography and risk.

Why This Matters

Big Bend is:

An iconic National Park
A wild and scenic river
Texas’ largest state park
An International Dark Sky Reserve
Rich in biodiversity
A cultural borderland thousands of years old
A floodplain governed by international treaty

Federal audits, peer-reviewed science, and historical flood events document:

Hydrologic risk
Wildlife fragmentation
Cultural site damage
Long-term mitigation uncertainty

IMPACTS ARE NOT THEORETICAL. THERE IS ABUNDANT DOCUMENTED PRECEDENT.

SOURCES

Federal Oversight

U.S. Government Accountability Office (GAO). Southwest Border: Additional Actions Needed to Address Cultural and Natural Resource Impacts from Barrier Construction. GAO-23-105443. Sept. 2023. https://www.gao.gov/products/gao-23-105443

U.S. Government Accountability Office. Progress and Challenges with the Use of Technology, Tactical Infrastructure, and Personnel to Secure the Southwest Border. GAO-18-397T. March 2018. https://www.gao.gov/products/gao-18-397t

Peer-Reviewed Research

Harrity, E., Traphagen, M., Bethel, M., Facka, A. (2024). USA-Mexico border wall impedes wildlife movement. Frontiers in Ecology and Evolution. DOI: 10.3389/fevo.2024.1487911
https://www.researchgate.net/publication/386430124_USA-Mexico_border_wall_impedes_wildlife_movement

Middleton, B. A. (2024). USGS study on pollinator movement and border infrastructure (South Texas). https://pubs.usgs.gov/publication/70265980

Trouwborst, A., Fleurke, F., Dubrulle, J. (2016). Border Fences and their Impacts on Large Carnivores, Large Herbivores and Biodiversity. Review of European Comparative & International Environmental Law. https://repository.tilburguniversity.edu/server/api/core/bitstreams/032dfcbe-57b9-4e72-a369-18ed6898e5e6/content

Peters, R., et al. (2018). Nature Divided, Scientists United. BioScience. https://trophiccascades.forestry.oregonstate.edu/sites/default/files/peters2018_wall.pdf

Flood Case Documentation

Associated Press. Border blunder: Security fence causes flooding. Aug. 25, 2008 https://www.nbcnews.com/id/wbna26396487

Del Bosque, M. (2018). Trump’s Border Wall Could Cause Deadly Flooding in Texas. Texas Monthly. https://www.texasmonthly.com/news-politics/trumps-border-wall-cause-deadly-flooding-texas-federal-officials-planning-build-anyway/

Reese, A. (Scientific American). Trump’s Border Wall Could Cause Flooding in Texas. https://www.scientificamerican.com/article/trumps-border-wall-could-cause-flooding-in-texas/

Big Bend Project Scope

Karas, S. (2026). Feds waive environmental protections to fast-track Big Bend wall. Big Bend Sentinel https://bigbendsentinel.com/2026/02/18/feds-waive-environmental-protections-to-fast-track-big-bend-wall/

Economic & Effectiveness Research

Allen, T., Dobbin, C. de C., Morten, M. (2018). Border Walls. NBER Working Paper No. 25267. ACLU Border Rights Center et al. (2019). Death, Damage, and Failure. https://www.nber.org/system/files/working_papers/w25267/revisions/w25267.rev1.pdf?utm_campaign=PANTHEON_STRIPPED&utm_medium=PANTHEON_STRIPPED&utm_source=PANTHEON_STRIPPED