Mich. Comp. Laws § 397.179: Appointed board members; number; right to appoint; term; vacancy.

Sec. 9.

If an agreement prescribes appointed board members, the board shall consist of not fewer than 5 and not more than 8 members. The agreement may provide that the right to appoint 1 or more board members rotates between 2 or more municipalities. A term shall not be more than 4 years. A member shall serve until the appointment and qualification of a successor. A vacancy shall be filled for the unexpired term by the participating municipality that appointed the member whose position is vacant.