President Donald Trump held up San Diego as an American example of why walls have worked in stemming illegal immigration during his annual State of the Union speech Tuesday night.
Whether that’s true is a nuanced answer — San Diego did see fewer apprehensions of undocumented immigrants at the border south of San Diego after a barrier was finished there in 1996, though it’s generally considered fencing and not a wall.
Trump has been calling for a wall along the U.S.-Mexico border, an ongoing disagreement with members of Congress that caused a 35-day government shutdown and could prompt another if lawmakers don’t come to an agreement by mid-February. He has wavered on language, calling it a wall, steel slats and a steel barrier. He has at times criticized people who call it a fence, but at other times referred to it as a fence himself.
“San Diego used to have the most illegal border crossings in the country,” Trump said. “In response, and at the request of San Diego residents and political leaders, a strong security wall was put in place. This powerful barrier almost completely ended illegal crossings.”
San Diego did have the most illegal border crossings at one point in time, according to data by the U.S. Border Patrol. In 1986 there were about 630,000 undocumented immigrants apprehended in the San Diego sector alone.
The border south of San Diego has had multiple layers of barriers built since 1989, according to a historical look at the issue by the San Diego Union Tribune.
The first layer was comprised of old helicopter landing pads welded together, finished in 1989. It was 46 miles long, rising to heights of 6 feet to 10 feet.
But between 1989 and 1990, apprehensions of undocumented immigrants at the border in the San Diego sector increased, from about 367,000 to 473,000, according to the Border Patrol. That was consistent with a rise in apprehensions across the southern border.
A second layer of fencing made of steel mesh, 13 miles long and 15 feet to 18 feet high, was finished in 1996. Apprehensions of undocumented immigrants in the San Diego sector decreased sharply between 1996 and 1997, from about 484,000 to 284,000. That 40 percent decrease was not consistent with numbers in other border sectors that year.
However, the fencing was not the only significant change in border enforcement in San Diego in the mid-1990s. Operation Gatekeeper was also targeted specifically to San Diego starting in 1994, which involved more agents and technology “concentrated in specific areas.” It included 200 more agents to guard 14 miles of border south of San Diego.
“Between the port of entry at Highway 5 and the ocean, there is a fence, high intensity lights, and three lines of agents, all designed to advertise to potential illegal entrants that illegal entry will result in apprehension,” the nonpartisan Migration News described Operation Gatekeeper. Those apprehended were also fingerprinted electronically, so Border Patrol agents could identify people who tried to illegally cross the border multiple times.
Smaller chain-link fences in high traffic areas also are installed after the first two layers, and a newer, steel 30-foot fence to replace the welded helicopter pads was built between February and October 2018.
Comprehensive figures on illegal border crossings broken down by sector are not yet available for the end of 2018, so the effectiveness of the new fencing is currently unknown.
The most recent figures available for the San Diego sector were 2017, when there were 26,086 apprehensions of undocumented immigrants in that sector. Those crossings had — for the most part — steadily decreased ever since 1997.