Donald Trump’s US border wall, vulnerable to flash floods, needs large storm gates left open for months

From the article:

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.

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John Ladd, whose cattle ranch extends along the border for about 10 miles west of tiny Naco, said the Border Patrol and the Army Corps of Engineers began installing 18-foot bollards on his property in 2008, adding “lift gates” that could be opened during the summer to allow floodwaters through.

Ladd, who supports Trump and his wall project, said his span of the border now has about 70 gates, and U.S. agents use a forklift to raise them at the beginning of every summer. They initially were designed to be hoisted by agents using the winch on their Border Patrol vehicles, Ladd said, but the gates were so heavy that “the front end of their trucks would start lifting off the ground.”

When the gates were first installed on Ladd’s ranch, smugglers would drive through the openings with loads of marijuana, he said, so the Border Patrol lowered the height of the opening to four feet. The vehicle incursions have stopped, but illegal crossings and smuggling increase along his property during the summer months when the gates are left open, the rancher said.

“They know as soon as the Border Patrol opens them,” he added, referring to traffickers in Mexico.

[...]

But Villareal and other Border Patrol officials said the storm gates, and their need to be left open all summer, amount to a relatively minor challenge that can be compensated for using technology such as cameras and sensors — along with more agents.

They also say a barrier with openings is preferable to no barrier at all, and the gaps can help them by funneling foot traffic into areas where they can concentrate their interdiction efforts.

[...]

The gates have created logistical problems for U.S. officials, who must physically lift and lower the gates with the changing of the seasons. In the fall, Border Patrol crews sometimes struggle to close the gates on Ladd’s Arizona ranch, he said, because the openings accumulate rocks and sand during the summer.

Despite what border officials said about sensors, Ladd said agents have told him they cannot leave sensors in the stream channels and canyons while the gates are open because they, too, risk being swept away by flash floods. He said he has not seen an increase in summer patrols, either.