Michigan Compiled Laws, Chapter 125. Planning, Housing and Zoning § 125.2468

Sec. 18. (1) An authority board may carry out an improvement, provide for the payment of an improvement by the issuance of bonds as provided in section 32,  1 and determine that the whole or any part of the cost of an improvement shall be defrayed by special assessments against property located within the authority district and especially benefited by the improvement. The cost of architectural, engineering, legal, and accounting services and all expenses, including expenses under section 37,  2 incident to the proceedings for the making and financing of the improvement shall be considered to be a part of the cost of the improvement.

(2) A road under the jurisdiction of either the state transportation department or the board of county road commissioners shall not be improved under this act without the written approval of the state transportation department or the board of county road commissioners. As a condition to the granting of the approval, the state transportation department or the board of county road commissioners may require 1 or more of the following:

(3) The authority board may proceed to carry out an improvement unless a petition objecting to the improvement is filed with the authority board at or before the hearing provided in section 19  3 signed by record owners representing 1/5 of the votes that could be cast in an election under section 9(5)(a). 4

(4) An authority board may require the filing of a petition supporting an improvement meeting the requirements of subsection (5) before proceeding with an improvement under this act.

(5) If a petition objecting to an improvement is filed as provided in subsection (3), or if the authority board requires a petition supporting an improvement before proceeding, the authority board shall not proceed with the improvement until a petition supporting the improvement signed by record owners representing 2/3 of the votes that could be cast in an election under section 9(5)(a) is filed with the authority board.

(6) A petition filed under this section may be supplemented as to signatures by the filing of an additional signed copy or copies of the petition, and the validity of the signatures on a supplemental petition shall be determined by the records as of the day of filing the supplemental petition.