The open, unmanned gates in remote areas already have allowed for the easy entry of smugglers and migrants into the United States.
At locations along the U.S. southern border where such gates already are in operation, Border Patrol agents must manually raise them every year before the arrival of the summer thunderstorms that convert riverbeds into raging torrents that carry massive amounts of water and debris, including sediment, rocks, tree limbs and vegetation.
Trump’s wall, which features 30-foot metal bollards spaced four inches apart, effectively acts as a sewer grate that traps the debris; when clogged, the barriers cannot withstand the power of the runoff.
Because the gates typically are located in isolated areas that lack electricity, they cannot be operated from afar. That requires the Border Patrol to leave the gates open for months, increasing the need for U.S. agents to monitor the sites because smugglers and other border-crossers can enter through the large gaps and advance northward following stream channels and narrow canyons to avoid detection.
The flooding risks are one of the biggest engineering challenges to the president’s vision of a linear man-made structure spanning hundreds of miles of desert, canyons and mountains. But the Trump administration has said little about how it plans to manage the hydrology of the border region.
Though Trump has boasted that his new “border wall system” will be an impermeable force against illegal crossings and drug trafficking, the need for open gates is another notable weakness that smugglers and migrants can exploit to slip through the barrier and evade capture.
Smugglers have learned how to cut through the new steel bollards using common tools they can buy at hardware stores, and some have demonstrated that the wall can be climbed with handmade ladders and rope. And most of the hard narcotics that enter the United States via Mexico pass through official border crossings, hidden in vehicles and among cargo, not through the remote areas where Trump’s new barriers are being erected.
Roy Villareal, chief of the Border Patrol’s Tucson sector, which covers most of Arizona, described the addition of the floodgates as an example of how his agency has learned to adjust to the realities of the Southwest’s extreme weather and topography.
“The border is so diverse,” Villareal said. “You have to plan for water flow. . . . People think it’s just this monolithic wall, sort of like the Great Wall of China, where you drop it into place and that’s all there is to it. And that’s not the reality at all.”