Mich. Comp. Laws § 113.4

Sec. 4. The by-laws and ordinances of any such city and the rules and regulations of the council, and of the board of health or other board or boards of such city heretofore in force and not inconsistent with this act shall remain in force after the passage of this act and are hereby declared to be reenacted by virtue of and under the powers conferred by this act until altered amended or repealed by the council or such board as the case may be.