 By the early 1970s, a project was underway to reconstruct LA 47 as a modern four-lane highway connecting Chalmette with the new Gulf Intracoastal Waterway bridge.This involved the construction of a new roadway embankment through the swamp running parallel to the existing two-lane highway as well as a new fixed span bridge across Bayou Bienvenue.The entire corridor was intended to become part of I-410, a planned southern loop around New Orleans designated in 1969 that would connect with I-10 on either side of the city.