(a) Before the board issues bonds, the board, on its own motion or on request of a landowner in the district, may petition the commissioners court for the addition of land to or exclusion of land from the district.
(b) If the commissioners court unanimously determines from the evidence that the best interests of the persons and property in the district will be served by adding or excluding land, the commissioners court shall enter in its records the appropriate findings and order adding or excluding land.