No person shall cause a truck or other vehicle while being used for commercial purposes to enter upon, use, or traverse any portion of any park area or any park road except in the service of the Department at the request of the employees of the Department, or by express permission of the manager for a special activity not inconsistent with park use; provided, that, the provisions of this section shall not apply to City roads or state highways. [Ord. 126 § 1, 1997.]