S.C. Code Ann. § 56-21-70

The Department of Behavioral Health and Developmental Disabilities may adopt and promulgate rules and regulations governing and controlling use of the roads, streets and parking facilities by operators of vehicles within the area and lands of the State Hospital and Midlands Center. No such rules and regulations shall be in conflict with any State law on the subject, all of such State laws being hereby declared in force and applicable to the roads, streets and parking facilities under the control and authority of the Office of Mental Health. Copies of the rules and regulations shall be filed with the administrative heads of both institutions, the Secretary of State, the Code Commissioner, the city of Columbia and the magistrate's office in Upper township in Richland County.