20-169. Powers of local authorities.
Local authorities, except as expressly authorized by G.S. 20-141 and 20-158, shall have no power or authority to alter any speed limitations declared in this Article or to enact or enforce any rules or regulations contrary to the provisions of this Article, except that local authorities shall have power to provide by ordinances for any of the following:
(1) Regulating traffic by means of traffic or semaphores or other signaling devices on any portion of the highway where traffic is heavy or continuous.
(2) Prohibiting other than one-way traffic upon certain highways.
(3) Regulating the use of the highways by processions or assemblages.
(4) Regulating the speed of vehicles on highways in public parks.
(5) Authorizing law enforcement or fire department vehicles, ambulances, and rescue squad emergency service vehicles, equipped with a siren to preempt any traffic signals upon city streets within local authority boundaries or, with the approval of the Department of Transportation, on State highways within the boundaries of local authorities. The Department of Transportation shall respond to requests for approval within 60 days of receipt of a request.
Signs shall be erected giving notices of the special limits and regulations under subdivisions (1) through (4) of this section.