If a toll is administered on a project by the Department of Transportation, the toll must be used to pay for the construction, maintenance costs, and other expenses for only that project. A toll project that is in excess of one hundred fifty million dollars may only be initiated as provided in Chapter 37 of Title 4.
No toll may be imposed on passage of any vehicle on federal interstate highways in this State which were in existence as of January 1, 1997, unless the imposition is otherwise affirmatively approved by the General Assembly in separate legislation enacted solely for that purpose.