BOUNDARIES OF AUTHORITY.
Tex. TRANSP Code § 452.704.
in effect(a) Except as provided by Section 452.707 , the territory proposed to be included in an authority must contain all territory:
(1) in the county of the principal municipality; and
(2) in each unit of election that has the majority of its population in the county of the principal municipality.
(b) The territory may include territory in a county having a population of more than 52,000 adjacent to the county of the principal municipality.
(c) Notwithstanding Section 311.032 , Government Code, or other law, this section is not severable.