La. Roads, Bridges and Ferries § 48:304
The highway authorities may designate and establish controlled-access highways as new and additional facilities or may designate and establish an existing street or highway as included within or being a controlled-access facility.
They may provide for the elimination of intersections at grade of controlled-access facilities with existing state and parish roads or municipal streets by grade separation or service roads or by closing off roads and streets at the right of way boundary line of the controlled-access facility. After the establishment of any controlled-access facility, no highway or street which is not part thereof shall intersect it at grade. No municipal, parish or state highway, or street, or other public way shall be opened into or connected with any controlled-access facility without the consent and previous approval of the highway authority having jurisdiction over the facility. Such consent and approval shall be given only if the public interest is served thereby.
Provided however that notice of intent to establish such controlled-access facility within a municipality or within five miles thereof shall be delivered to the executive offices of such municipality together with plats outlining in reasonable detail the proposal not less than thirty days prior to the undertaking of such construction.
Provided further that in the event of objection to such proposal by the governing authorities of such municipality the same shall not be undertaken except after a public hearing by the board of highways.
After such public hearing a decision by the board of highways relative thereto shall be final.
La. Roads, Bridges and Ferries § 48:304