SANTA TERESA, New Mexico (Border Report) — An imposing 30-foot steel barrier is rising above the southern New Mexico desert, part of the Trump administration’s push to wall-off the Mexican border.

Workers on Friday could be seen digging trenches and fastening steel bollards to a concrete base several miles east of Columbus, New Mexico, an empty stretch where in years past U.S. Border Patrol agents often reported catching drug smugglers and groups of migrants coming over from Mexico.

The structure is replacing miles of squat steel vehicle barrier easily bypassed by smugglers on foot. Its height also poses a challenge both to migrants and drug cartel members who’ve used ladders to get over sections of older 18-foot steel bollard in nearby Santa Teresa, New Mexico.

“Smuggling organizations prefer to use these rural areas because they believe there’s going to be an opportunity for them to be more successful. So erecting a fence of this size that is so robust that can potentially just deter these (incursions) is a big plus for us,” said Mario Escalante, acting supervisory agent of the U.S. Border Patrol El Paso Sector.

Contractors say they’ve built 6 miles of border wall since August and have 40 more miles to go. The area for years has presented smugglers an opportunity to reach New Mexico Highway 9 to Columbus, then Interstate 10 West to Tucson and Phoenix in Arizona, and eventually, California.

Unlike other parts of the country where federal officials are struggling to obtain right-of-way over private land, wall construction in New Mexico has been swift. The upgraded barrier here sits on federal land.

But that doesn’t mean no opposition or litigation.

Environmentalists: Wall threatens survival of wildlife

Immigrant advocates point to a dramatic decrease in migrant apprehensions in recent months to question the need for “exaggerated” structures. And local environmentalists have joined a lawsuit to stop the wall. They say the fence endangers wildlife of the region such as bobcats, javalinas and mountain lions.

“Before they built the wall there was nothing to prevent (these species) from going back and forth across the border line. Now there is. We have made it very clear that the wall will harm wildlife,” said Kevin Bixby, executive director of the Southwest Environmental Center in Las Cruces.

Bixby said the nature conservancy group has set up cameras to capture wildlife in the desert west of Santa Teresa, and that it is plentiful. “We captured photos and videos of mountain lions, mule dear, bobcats, javelina, coyotes, foxes, badgers. All those species are too big to get through the wall,” Bixby said. “The wall is going to create a barrier to their movement, their ability to get to the water, the mates, the gene pool they need to survive.”

He expects some individual animals to die, but more importantly, he said, the wall will divide populations across the border, making the smaller population vulnerable to extinction — for lack of food in the short-term and due to inbreeding in the long-term.

Bixby said the group expressed its concerns to the Army Corps of Engineers, which is in charge of supervising wall construction. “I don’t think we ever got an answer,” he said.

He added that the lawsuit to stop construction under the argument that military funds are improperly being used to pay for various wall projects, is moving through the courts, but that the federal government got the green light to keep building in the meantime.

Border Report reached out to the Corps for comment but got no response on Friday. A federal official at the construction site stated that environmental studies are done before any section of wall is started.

Bixby said that Congress in the mid-2000s gave the executive waiver authority under national security grounds to not comply with dozens of federal environmental laws. “Every time a new section of wall is built, the government uses this waiver authority so it doesn’t have to comply with the Endangered Species Act and all kinds of laws,” he said. “I think it was used five times by George W. Bush and some 15 times by the Trump administration.”

Why build a bigger wall when migrants are turning themselves in?

Both Bixby and Fernando Garcia, executive director of El Paso’s Border Network for Human Rights, said the scope of border wall construction doesn’t match the reality of the migrant issue.

Garcia earlier told Border Report that the Department of Homeland Security was “inflating” its apprehension statistics last year by including hundreds of thousands of lawful asylum seekers as “apprehensions.”

“They were not trying to evade or sneak by the Border Patrol; they were presenting themselves to (agents) to exercise their right to petition for protection under U.S. asylum laws,” he said.

Bixby noted that drug-smuggling occurs primarily at established ports of entry, not at remote points like where the wall is being built.

These charts show how much drugs are seized at ports of entry (light orange) and how much in between legitimate land crossings.

“Most of that is taking place at the ports of entry, the drugs are coming in inside vehicles. They aren’t being crossed, for the most part, out in the desert so walls aren’t going to stop that,” he said.

The Border Patrol, however, welcomes the wall.

“It’s been the case not just recently, but over the past decade: Tactical infrastructure helps our mission. Any time you give us additional tools, it certainly helps us,” Escalante said.

Visit the homepage for the latest exclusive stories and breaking news about issues along the United States-Mexico border.