Mich. Comp. Laws § 123.332

Sec. 2. When any public corporation shall have acquired any water or sewage disposal system, and, by subsequent incorporation, annexation or other change of boundaries, the land in which any part of such system lies shall have been placed within the boundaries of any other public corporation, the legislative or governing body of such other public corporation, if it desires to acquire that part of such system lying within its boundaries, shall submit the question of acquiring the same to vote of its qualified electors at a regular or special election.