Barriers to a Border Wall

Although the latest spending bill did not include funds for it, President Donald Trump is not backing down from his pledge to build a nearly 2,000-mile wall along the Mexican border. Designs are being solicited, and construction of prototype barriers is scheduled to begin in San Diego this summer. But fulfilling Trump’s signature campaign promise won’t be easy. Mexico says it won’t pay, Democrats are opposed, and even GOP allies suggest a wall spanning the full border is unrealistic. Here are some other challenges facing the project:

Current barriers

The U.S. first began erecting physical fencing in 1990, though most was built beginning in 2006. Today roughly one-third of the Southern border features barricades of some type:

BOLLARD FENCE

Constructed of upright posts embedded in the ground, these barriers are designed to deter mass crossings.

STEEL MESH

This modern style of fencing is double-layered, which makes it harder for border crossers to cut through it with bolt or pipe cutters.

LANDING MAT

Made from Army-surplus carbon steel laid down for helicopters in the Vietnam War, it’s one of the oldest types of barriers used.

PEDESTRIAN

NORMANDY

These crisscrossed posts are meant to impede vehicles. But smugglers have driven over them by laying down wooden ramps.

VEHICLE

MAP KEY

Illegal entries 2013–15

= 10,000

APPREHENDED SHOWN IN GRAY

Existing fencing

Pedestrian

Vehicle

None

[The following text appears within a map. Please see hardcopy or PDF for actual map.]

L.A.

San Diego

San Ysidro

WEATHER

San Diego County has 14 miles of multilayer fencing, plus cameras and lights. But people can still scramble across under the blankets of fog common to the area.

97,000

Tijuana

CALIFORNIA

53,000

Calexico

Mexicali

BAJA CALIF.

Pacific Ocean

Colorado River

19,000

Yuma

San Luis

Río Colorado

Gulf of California

ARIZONA

Phoenix

Sonoran Desert

U.S.

MEXICO

DEADLY TERRAIN

Barriers and patrols in cities have funneled migrants to the Sonoran Desert. While some make it across the waterless expanse on foot, thousands have perished.

393,000

Sasabe

Nogales

Nogales

SIGHT LINES

Some existing fence segments obscure views. Before landing-mat panels were replaced in Nogales, agents couldn’t see smugglers coming or the rocks sometimes thrown.

SONORA

Douglas

Agua Prieta

Cananea

NEW MEXICO

61,000

Columbus

Palomas

Nuevo Casas Grandes

Las Cruces

El Paso

Ciudad Juárez

EROSION AND DRAINAGE ISSUES

Border towns have flooded when fencing hampered water flow. Outside El Paso, accumulated debris and sand reduced the barrier’s height by 2 ft.

Rio Grande

CHIHUAHUA

Chihuahua

9,000

BIG BEND NATIONAL PARK

DISRUPTING WILDLIFE

Big Bend National Park is known for its biodiversity. Animals here would suffer if a wall hindered migration routes or access to food and water.

Presidio

Ojinaga

U.S.

MEXICO

COAHUILA

TEXAS

A RIVER RUNS THROUGH IT

A 1970 treaty with Mexico stipulates that structures should not disrupt the natural flow of the Rio Grande, whose winding path makes construction difficult.

51,000

Del Rio

Ciudad Acuña

Eagle Pass

Piedras Negras

124,000

Laredo

Nuevo Laredo

NUEVO LEÓN

Monterrey

Roma

LAND RIGHTS

Much of the Texas border is private ranchland. Of hundreds of lawsuits filed over parcels taken for the Secure Fence Act of 2006, a fifth are still outstanding.

Gulf of Mexico

531,000

McAllen

Reynosa

Brownsville

Matamoros

The entire border spans 1,991 miles–that’s nine times the distance from Earth to the International Space Station

TIME GRAPHIC BY EMILY BARONE AND LON TWEETEN

100 MILES

100 KM

Checking the flow

[The following text appears within a chart. Please see hardcopy or PDF for actual chart.]

APPREHENSIONS ON THE MEXICO BORDER

1.5 million

1 million

500,000

0

408,870

2000

’05

’10

2016

[The following text appears within a map. Please see hardcopy or PDF for actual map.]

WHERE MIGRANTS COME FROM

El Salvador

13%

Mexico

56%

Honduras

10%

Guatemala

17%

Other

4%

BASED ON APPREHENSIONS IN 2015

MAINTAINING THE FENCES

$784

Average cost to repair each breach

9,287

Number of breaches from 2010 to ’15

$2.3 billion

Total fencing costs from 2007 to ’15

THE PROTOTYPES

4 to 8

Number of designs to be selected for prototypes

$20 million

Cost to build the prototypes (funding already appropriated)

473

Number of companies expressing initial interest in wall construction

SOURCES: GAO; DHS; FEDBIZOPPS.GOV; UNIVERSITY OF TEXAS AT AUSTIN (FENCE LOCATIONS); NEWS REPORTS; CRS. NOTE: ILLEGAL ENTRIES 2013–15 FROM FEBRUARY 2017 GAO REPORT.