La. Roads, Bridges and Ferries § 48:301
The highway authorities of the state, parishes and municipalities of Louisiana, acting alone or in cooperation with each other or with any federal, state, or local agency or any other state having authority to participate in the construction and maintenance of highways, may plan, designate, establish, regulate, vacate, alter, improve, maintain and provide controlled-access facilities for public use whenever they determine that traffic conditions, present or future, justify such special facilities. However, within municipalities, the exercise of this power is subject to such municipal consent as is necessary by law.
In addition to the specific powers granted in this Part, they also have, relative to controlled-access facilities, all additional authority now or hereafter vested in them relative to highways or streets within their respective jurisdictions. They may regulate, restrict, or prohibit the use of controlled-access facilities by the various classes of vehicles or traffic in a manner consistent with R.S. 48:1(12).
La. Roads, Bridges and Ferries § 48:301