It's really happening.
President Donald Trump is expected to sign an executive order on Wednesday to begin funding and construction of a border wall between the US and Mexico, fulfilling one of his longest-held campaign promises.
It's highly unlikely that Mexico will pay for the wall — Mexican lawmakers have repeatedly said they wouldn't — so the substantial cost will likely fall on the US government.
To get a sense of just how massive the undertaking of the wall would be, analysts at Bernstein calculated the possible costs in a note to clients in July. The estimated cost would be at least $15 billion, according to the analysts, and possibly as much as $25 billion.
The Bernstein note made some assumptions based on Trump's previous proposals, and since Trump has not yet provided the exact dimensions of the wall, we'll have to work with those for now.
The Bernstein analysts based their cost estimate on the current price of the existing border fencing, along with additional costs Trump's proposed wall would incur.
"The cost to build the 'easiest' sections of the existing fence were between $2.8 [million to] $3.9 million per mile, according to the US Government Accountability Office," the Bernstein note said. "However, given that these figures exclude labor costs, land acquisition costs, and relate to construction in accessible areas with favorable construction conditions, the cost of Trump's wall is widely expected to be greater than $15 billion and perhaps as much as $25 billion."
The analysts predicted the wall would be 40 feet tall and 1,000 miles long, go 7 feet underground (to prevent tunneling), and be 10 inches thick. The simplest construction material to use would be concrete, according to the analysts — and based on concrete prices and the estimated size of the wall, that cost alone would be around $700 million.
Bernstein noted that materials suppliers in the southwestern US and Mexico could stand to gain significantly from the project's construction, since it would be difficult to transport the large amounts of materials needed across long distances:
"What is less clear at this stage is whether US- or Mexico-based suppliers will benefit. In fact, despite arguments concerning which government will pay for construction, the large quantities of materials required may necessitate procurement from both sides of the border. Cemex appears best positioned regardless, with cement, RMX, and aggregates facilities throughout the border region. Other companies who we would expect to benefit the most include CalPortland, GCC, Martin Marietta, and Vulcan."
Additionally, the topography along the border would make building the wall challenging:
"The border presents huge topographical challenges to construction. It runs through remote desert in Arizona, over rugged mountains in New Mexico, and, for two-thirds of its length, along rivers. The region also includes protected wildlife refuges, Indian territory, and ranches whose owners are unlikely to willingly agree to sell their land to the federal government. Allowances must be made for flooding, since the border crosses numerous floodplains."
Add onto that the fact that Trump has pledged $550 billion in infrastructure spending and reportedly has already prioritized $137 billion in projects across the US, and it appears there will be a lot more government spending by the Trump administration.
At the time, the Bernstein analysts said the wall sounded "ludicrous," but now their analysis may come in handy as the plan is coming to fruition.
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