Tenn. Code Ann. § 69-11-125: Local regulation restricted

(a) Except as provided in subsection (b), no municipality, county, nor any group of counties, or other person, shall regulate, supervise, or provide for the regulation or supervision of any dams or reservoirs within their jurisdictions, including the construction, maintenance, operation, removal, or abandonment of dams or reservoirs, nor to limit the size of a dam or reservoir or the amount of water that may be stored in dams or reservoirs, where the exercise of such authority would conflict with the powers and authority vested in the commissioner by this chapter.

(b) Home rule municipalities in counties with a population of over six hundred thousand (600,000) according to the 1970 federal census, or any subsequent federal census, may exercise an option by ordinance to adopt regulations governing, supervising or otherwise controlling such dams and reservoirs within the city or county within a period of one (1) year from April 1, 1974, or in the case of local governments created after July 1, 1974, within one (1) year following the creation of such government, which shall be consistent with these regulations but may be more restrictive and require municipal approval of such plans and specifications.

(c) If, at any time, the commissioner determines that the political subdivision's regulations or their enforcement are inconsistent or less stringent than state requirements, the commissioner shall require the political subdivision to comply with state regulations.