Tennessee Code Title 7. Consolidated Governments and Local Governmental Functions and Entities § 7-51-804

(a) No ordinance required to be filed with the commissioner of transportation shall be effective as to the operation of any train until fifteen (15) days after the service of a copy of such ordinance upon the registered agent of the railroad operating such train.

(b) As to any railroad failing to furnish to the commissioner the name and address of its registered agent for service of process, any ordinance affecting the operation of the trains of such railroad shall become effective upon receipt of the certified copy thereof by the commissioner.