Mich. Comp. Laws § 103.5

Sec. 5. The council shall have power to regulate and prohibit the placing of signs, awnings, awning posts, and of other things upon or over sidewalks, and to regulate or prohibit the construction and use of openings in the sidewalks, and of all vaults, structures and excavations under the same; and to prohibit and prevent obstructions, encumbrances or other nuisances upon the walks.