The last southbound Interstate 5 exit before the U.S.-Mexican border was expected to be closed, beginning Monday, for pipe installation work, but that is no longer the case.. The work is taking place near the Camino De La Plaza off-ramp in San Ysidro, according to Caltrans. WATCH HERE WATCH HEREThere had been some concern that those who do not exit on time would be directed across the border into Mexico. On Monday afternoon, though, Caltrans said that " Caltrans will no longer be closing close the Camino De La Plaza 'Last U.S. Exit' off-ramp at southbound Interstate 5 (I-5) in San Ysidro." Still happening: Nearby residents can expect increased noise and traffic in the area, Caltrans officials said.