Mich. Comp. Laws § 247.853

Sec. 3. (1) If a highway authority does not consent to accept jurisdiction over a highway proposed for transfer, within 90 days after its consent is requested in writing, unless an extension of time is agreed to by both parties, the state or county highway authority proposing the transfer may initiate proceedings for final determination of the question of the transfer of highway jurisdiction in accordance with the provisions of this act. (2) If the proposed transfer of jurisdiction is dependent upon the future opening of a new, relocated highway and approval of the new highway by both parties is required by law and the parties have not agreed to the transfer of jurisdiction as a condition of approval of the new highway, then the 90-day period shall not begin to run until the date that both parties approve the new highway.