(a) A municipality with a population of at least 250,000 according to the most recent federal decennial census and located in a county that has no principal municipality with a population of more than 1.1 million according to the most recent federal decennial census may join a separate authority by complying with this chapter.
(b) If a municipality described by Subsection (a) joins a separate authority and another separate authority is subsequently established in a county that has no principal municipality with a population of more than 1.1 million according to the most recent federal decennial census, any municipality in that county that has voted to participate with any authority created under this chapter may at the time of the creation of the new authority:
(1) remain in the authority that was created first;
(2) join the new authority in the county in which the municipality is located; or
(3) participate with both authorities.

(c) A municipality in which capital improvements have been made at its request by an authority must on its transfer to a different authority or participation with more than one authority continue to honor reimbursement obligations resulting from the improvements.