Tenn. Code § 13-3-406
From and after the time when the platting jurisdiction of any regional planning commission of any region has attached by virtue of the making and adoption of a major road plan as provided in § 13-3-402, no county or court or board or officer thereof or any other public officer or authority shall accept, lay out, open, improve, grade, pave or light any road or lay or authorize water mains or sewers or connections or other facilities or utilities to be laid in any road located within such region and outside of the boundaries of municipal corporations, unless such road has been accepted or opened or has otherwise received the legal status of a public road prior to the attachment of the planning commission's jurisdiction, or unless such road corresponds in its location and lines with a road shown on a subdivision plat approved by the planning commission or on a road plat made and adopted by the planning commission; provided, that the county legislative body of such county may accept or lay out any other road or adopt any other road location; provided further, that the resolution or other measure for such acceptance, laying out or adoption is first submitted to the planning commission for its approval and, if disapproved by the commission, receives the favorable vote of not less than a majority of the entire membership of the county legislative body; and a road approved by the planning commission upon such submission, or accepted, laid out, or adopted by the commission, shall have the status of an approved road location as fully as though it had been originally shown on a subdivision plat approved by the planning commission or on a plat made and adopted by the planning commission. In the case, however, of any state highway constructed or to be constructed in the region by the state of Tennessee with state funds as a part of the state highway system, the submission to the planning commission shall be by the commissioner of transportation, who shall have the power to overrule the disapproval of the planning commission.
T.C.A. § 13-3-406