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.
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