(1) “Alterations,” or “repairs,” or either of them, means only such alterations or repairs that may affect the safety of the dam or reservoir, as determined by the commissioner;

(2) “Commissioner” means the commissioner of environment and conservation, the commissioner's duly authorized representatives, and in the event of the commissioner's absence or a vacancy in the office of commissioner, the deputy commissioner;

(3) “Dam” means any artificial barrier, together with appurtenant works, that does or may impound or divert water, and that either:

(A) Is or will be twenty feet (20′) or more in height from the natural bed of the stream or watercourse at the downstream toe of the barrier, as determined by the commissioner; or

(B) Has or will have an impounding capacity at maximum water storage elevation of thirty (30) acre-feet or more. Any such barrier that is or will be less than six feet (6′) in height, regardless of storage capacity, or that has or will have a maximum storage capacity not in excess of fifteen (15) acre-feet, regardless of height, is not considered a dam, nor shall any barrier, regardless of size, be considered a dam, if, in the judgment of the commissioner, such barrier creates an impoundment used only as a farm pond. “Diversion weirs,” “roadbeds,” “water tanks,” and “wastewater impoundment barriers” as defined in this section are not dams;

(4) “Days” means calendar days, including Sundays and holidays;

(5) “Division” means the division of water management of the department of environment and conservation;

(6) “Diversion weir” means a structure substantially within the bed of a stream, designed to impound water only during low flow conditions, and that would not cause substantial overflow of water onto the downstream floodplain in the event of failure;

(7) “Enlargement” means any change in, or addition to, an existing dam or reservoir, that does or may raise the water storage elevation of the dam;

(8) “Farm pond” means any impoundment used only for providing water for agricultural and domestic purposes for the owner or occupant of the farm, the owner's or occupant's family, and invited guests, such as livestock and poultry watering, irrigation of crops, recreation, and conservation, but does not include any impoundment for which the water, or privileges or products of the water, are available to the general public;

(9) “Owner” means any person who owns an interest in, controls, or operates a dam;

(10) “Person” means any individual, firm, association, organization, partnership, business trust corporation, company, county, municipal or quasi-municipal corporation, public utility, utility or other district, the state of Tennessee and its departments, divisions, institutions, and agencies, and the duly authorized officers, agents, and representatives thereof, or any combination of any of the above. “Person” does not include the United States government nor any agency owned by the United States or any agency thereof, nor those who own a dam or reservoir leased to or operated by the United States or an agency thereof, nor those dams licensed by the federal power commission;

(11) “Reservoir” means any basin that contains or will contain the water impounded by a dam;

(12) “Roadbed” means the earth support work of a road that is not intended to impound water and that does not impound water continuously;

(13) “Wastewater impoundment barrier” means an artificial barrier impounding a body of wastewater for the purpose of treatment and designed so that no surface runoff from areas adjacent to the barrier is introduced into the impoundment;

(14) “Water” means that liquid, including solids or other matter dissolved or suspended in the liquid, that is or will be impounded;

(15) “Water storage elevation” means the maximum elevation of water surface that can be obtained by the dam or reservoir; and

(16) “Water tank” means a vessel designed and used to hold water.