La. Roads, Bridges and Ferries § 48:833
Parishes or municipalities proceeding under this Sub-part may enter on any lands, waters, and premises for the purpose of making surveys, soundings, and examinations. If deemed advisable, any such parish or municipality may exercise the right of expropriation and may institute condemnation proceedings under the provisions of the general laws providing for the construction and maintenance of highways and bridges in Louisiana or of any other pertinent general law of Louisiana for the purpose of acquiring any property to be used in connection with such construction. In any condemnation suit, the court having jurisdiction may issue such orders as are just to the parish, municipality, state and owners of the property to be condemned. Upon the institution of any such condemnation proceedings and upon tender of a bond or other security in sufficient sum to secure the owner or owners for damages and upon approval of the bond or other security by the court, the parish or municipality may take immediate possession of the property which is the subject matter of the condemnation proceedings and may enter thereon.
The State of Louisiana hereby expressly grants to any such parish or municipality full servitudes and rights of way in, through, across, and under or over any lands or property owned by the state which are necessary or convenient to the construction, acquisition, or efficient operation of any such causeways, tunnels, bridges, or combination thereof.
La. Roads, Bridges and Ferries § 48:833