cbp.gov
“Border Patrol expects that security improvements introduced by the new border wall may increase the threat of cross-border tunneling.”
Human flood detection
Since the border between the U.S. and Mexico is once again an immigration battleground, the war to staunch the flow of undocumented crossers from Mexico to San Diego is being fought in the frontier’s byzantine flood control and smuggling tunnels. So says the Homeland Security department’s Office of Inspector General.
“Since 1990, Border Patrol has discovered approximately 190 cross-border tunnels through manual methods such as human observation of traffic patterns, law enforcement efforts, and routine patrol operations,” per a newly released February 23 audit report. “For example, the San Diego sector has 36 storm drain tunnels that require 24/7 monitoring by patrol agents. These storm drain tunnels must often remain open to allow for normal operations and, absent technology capability, require direct p