(a) A municipality that has a population of more than 500,000 and that is located in a county with a population of more than one million may join a separate authority.
(b) If a municipality described by Subsection (a) joins an authority created under this chapter and another separate authority is subsequently established in the county in which the municipality is located, the municipality may:
(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 that has requested, participated in, or received a benefit of capital improvements made by an authority shall on its transfer to a different authority or participation with more than one authority continue to honor reimbursement obligations resulting from the improvements.