(a) If a tax is authorized at an election under Section 49.107, Water Code, the district may impose a tax to provide money:
(1) necessary to construct or acquire, maintain, and operate improvements, works, plants, and facilities considered essential or beneficial to the district; or
(2) adequate to defray the cost of the maintenance, operation, and administration of the district.
(b) An election for the imposition of taxes authorized by this section must be ordered by the board.