Michigan Compiled Laws, Chapter 123. Local Government § 123.167

Sec. 7. This act shall not repeal any existing statutory charter or ordinance provisions providing for the assessment or collection of water or sewage system rates, assessments, charges, or rentals by a municipality, but shall be construed as an additional grant of power to any power now prescribed by other statutory charter or ordinance provisions, or as a validating act to validate existing statutory or charter provisions creating liens which are also provided for by this act.