BATON ROUGE, La. — As the floodwaters swallowed Lyn Gibson’s two-story home, she hacked away on a hole near the roof, desperately trying to get to safety. She used a saw, a screwdriver and her feet, knocking her way through wood, vinyl and sheet rock. “I just kept picking and hitting and prying until I could get a hole big enough,” the slightly-built, 115-pound woman said.