Mich. Comp. Laws § 123.275

Sec. 5. Nothing in this act shall in any way impair, impeach, or in any way affect any right of action in law or in equity that may now exist in addition to the provisions of this act for the prevention of building plants or works, named in this act, nor shall this act in any way affect the right of any city or village to enact ordinances for their protection against such building plants or works in this act named. This act shall not apply to sewage disposal tanks, settling basins, apparatus or screens for the treatment of sewage matter, where the same are located within the confines of any city or village whose sewage constitutes part of the total sewage entering such a facility.