Michigan Compiled Laws, Chapter 124. Municipalities § 124.457

Sec. 7. A political subdivision or a portion of a city, village, or township bounded by lines described in section 4  1 may become a member of a public authority after the public authority's formation under this act upon resolution adopted by a majority vote of the members elected to and serving on the legislative body of the political subdivision requesting membership for all or a portion of the political subdivision and upon resolution adopted by a 2/3 vote of the members serving on the board of the public authority approving an amendment to the articles of incorporation of the public authority adding all or a portion of the political subdivision. The amendment to the articles of incorporation shall be executed by the clerk of the political subdivision, all or a part of which is being added and shall be filed and published in the same manner as the original articles of incorporation.