Prototypes of US president Donald Trump’s proposed border wall with Mexico have stood up to assaults by special forces during testing, an official has said.
Forces based in Florida and US Customs and Border Protection special units spent three weeks trying to breach and scale the eight prototypes in San Diego, using pneumatic drills, saws and other tools and climbing devices, the insider said.
A Customs and Border Protection report on the tests identifies strengths and flaws in each design, but does not pick an overall winner or rank them, though it does point to steel barriers topped by concrete as the best overall design, the official said.
The report recommends combining elements of each, depending on the terrain. The official likened the process to a Lego design, pulling pieces from different prototypes.
Carlos Diaz, a spokesman for Customs and Border Protection, said the agency is still in "the testing phase" and that results are being evaluated.
He said combining elements of different prototypes instead of picking a winner is consistent with previous statements by officials. He noted that the agency said in its bidding guidelines that a minimum height of 18ft would be a key characteristic. He said he did not have additional details on test results.
The administration has asked for 1.6 billion dollars this year to build or replace 74 miles of barriers in Texas’ Rio Grande Valley and San Diego, and plans to request another 1.6 billion dollar next year.
A proposal by Customs and Border Protection calls for spending 18 billion dollars over 10 years to extend barriers to cover nearly half the border, though it is unclear if Mr Trump supports that plan.
The agency proposes 316 miles of additional barrier by September 2027, bringing total coverage to 970 miles. It also seeks 407 miles of replacement or secondary fencing.
Contractors were awarded between 300,000 and 500,000 dollars for each prototype. These were built last autumn to guide future construction of one of Donald Trump’s signature campaign pledges. Four were concrete and four were made of other materials.
Ronald Vitiello, the agency’s acting deputy commissioner, said after visiting the prototypes in October that he was struck most by the 30ft heights, which are significantly higher than existing barriers. Taller barriers are undoubtedly more effective, but whether the cost is justified will be up for debate.
Mexico has steadfastly rejected Mr Trump’s demand that it should pay for the wall.