Since 1955, the most significant change to LA 24 has been the widening of much of the highway to four lanes. Previously, the designation existed solely on the west side of Bayou Terrebonne between Schriever and Houma. The opposite roadway, though discontinuous, had been part of the state highway system since 1930 as State Route 965, which became LA 659 in the 1955 renumbering. In the late 1970s, it was incorporated into the route of LA 24 to carry westbound traffic from Houma north to a point near the present US 90 interchange, which was soon to be constructed. By the late 1980s, the east bank roadway had been extended and improved to give LA 24 a continuous four-lane corridor between Schriever and Houma.