 The above segments of LA 47 serve not only as the primary north–south thoroughfare through Chalmette but also provide a vital hurricane evacuation route for residents of St. Bernard Parish and the east bank portion of Plaquemines Parish.LA 47 was designated in the 1955 Louisiana Highway renumbering, replacing former State Route 61.North of I-10, the route turns west along the shore of Lake Pontchartrain and follows Hayne Boulevard from Little Woods to a point near the New Orleans Lakefront Airport.