In addition to the powers now possessed by it, any parish or municipality may construct, acquire, improve, operate, and maintain tunnels, causeways, bridges, or any combination of such facilities, including all necessary approaches, fixtures, accessories, and equipment, in, over, through, or under the waterways of the state, the Gulf of Mexico, or any lakes, canals, bayous, bays, or inlets within the state or opening thereinto, and may pay the cost of such construction, acquisition, or improvement.
La. Roads, Bridges and Ferries § 48:831