Trump's wall, by one estimate, could cost $70 billion

If President Trump wants to see his border wall completed while he is still in office, he may have to convince members of Congress to cough up a lot more money than he originally promised the project would cost. Many times more, in fact, if a report from Democrats on the Senate Homeland Security and Governmental Affairs Committee is to be believed.

The report, issued Tuesday afternoon, uses information provided by the Department of Homeland Security in its requests for funding for similar barrier projects to extrapolate from cost estimates for a wall stretching almost the entire distance of the southern border.

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At the high end, the estimate tops out at nearly $70 billion, far more than the $12 billion Trump promised during his presidential campaign, and three times the $21.6 billion that an internal DHS report came up with in February.

Average Cost of Border Barrier
Average Cost of Border Barrier

To be sure, the report was authored wholly by the committee's Democratic members, who are uniformly opposed to the wall project in the first place and have every reason to paint it in as poor a light as possible. For example, the report appears to assume that the wall would extend across the entire border, virtually unbroken except in a few areas. DHS officials have said that in some areas the wall could be more of a fence and that in others electronic surveillance might be sufficient.

However, even if the estimate in the report is off by half, it would still represent a major upward shift in the project's cost. And regardless of the precision of the estimate, the report does raise some troubling questions about one of Trump's signature campaign promises.

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The report notes that internal estimates of the per-mile cost of a barrier wall have been increasing the longer DHS studies them. "The per-mile cost of the construction extrapolated from the FY 2017 supplemental request totals $16.1 million per mile and FY 2018 totals over $36.6 million per mile," the report finds.

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In addition, the price tag for building the wall does not include either the cost of acquiring the privately-owned land the government would have to build it on or the costs of maintaining the structure after it is completed.

The committee looked at what the federal government had paid for borderland in the past when estimating the potential cost of the project.

"In total, the U.S. government paid an average price per acre of $42,600," they found. "In one case in Cameron County, Texas, a landowner was initially offered $233,000 for 3.1 acres. After a three-year legal battle, the government eventually paid at least $4.7 million, a nearly 2,000 percent increase over the initial offer."

In many cases, where the government moved to take land from unwilling owners, cases have dragged on in court for years. "CBP has informed Committee staff that in over 90 instances, condemnation cases remain unresolved nearly 10 years later and the fence has not been built in those locations. The potential liability of the pending condemnation cases is $21 million."

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An effort to acquire land stretching the full length of the border could be more expensive by order of magnitude.

Finally, the report points out that maintenance of the wall once it's built could run to $150 million per year.

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