A growing number of illegal immigrants are crawling through San Diego's vermin-infested storm drains to avoid the Border Patrol. The 23-mile system of pipes surfaces in hundreds of storm grates and manhole covers in the industrial Otay Mesa area. Muddy immigrants make their way through the narrow pipes, which often carry toxic industrial sludge. They climb out of manholes and storm grates in Otay Mesa and take public transportation, taxis or are picked up in private vehicles to get from there to downtown San Diego, officials said. Border agents are have begun working with city engineers to map out the...