Tennessee Code Title 54. Highways, Bridges and Ferries § 54-5-129

If any county, county commission or road board, district, city, town, person or corporation desires immediately to improve any section of the state highway system as designated and established by the commissioner, the commissioner may enter into an agreement with the county, county commission, or road board, district, city, or town officials, or other parties, to finance the construction or reconstruction of the highway or section of the highway, and any funds advanced to the commissioner pursuant to the agreement shall be repaid without interest, as and when the general assembly may provide the funds, and the commissioner may apportion the funds for the improvement.