Tenn. Code Ann. § 65-6-127

Any railroad company owning or operating any railroad or any part thereof in the state, whether chartered under the laws of this state or under the laws of any other state or states, is empowered to build cut-off lines, branch lines, and other lines for the purpose of the better and more expeditious handling of the public business in the transportation of freight and passengers, and to construct, build, or extend any main line, branch line, or other line into, and to serve, other and different territory, and to build second main or double tracks, turnouts, switches, spur tracks, side-tracks, stations, depots, and terminal facilities.