Ala. Code § 23-3-3

The Director of Transportation, acting alone or in cooperation with counties, cities, towns or any federal, state or local agency or any other state having authority to participate in the construction and maintenance of highways, is authorized to plan, designate, establish, regulate, vacate, alter, improve, maintain, and provide controlled access facilities for public use wherever such authority or authorities are of the opinion that traffic conditions, present or future, will justify such special facilities; provided, that in the case of designation or vacation, such designations or vacations must be approved by the Director of Transportation. Said authorities may regulate, restrict, or prohibit the use of such controlled access facilities by the various classes of vehicles or traffic in a manner consistent with Section 23-3-1.