(A) Except as provided in ILCS Ch. 625, Act 5, 15-316(g), the City Council, with respect to highways under its jurisdiction, may, by ordinance or resolution, prohibit the operation of vehicles upon any highway, or impose restrictions as to the weight of vehicles to be operated upon any highway, for a total period of not to exceed 90 days, measured in either consecutive or nonconsecutive days at the discretion of the city council, in any one calendar year, whenever any highway by reason of deterioration, rain, snow, or other climate conditions will be seriously damaged or destroyed, unless the use of vehicles thereon is prohibited or the permissible weights thereof reduced.
(B) The City Council, after enacting any such ordinance or resolution, shall erect or cause to be erected and maintained signs designating the provision of the ordinance or resolution at each end of that portion of any highway affected thereby, and the ordinance or resolution shall not be effective unless and until the signs are erected and maintained. To be effective, an ordinance or resolution passed to designate a Class II roadway need not require that signs be erected, but the designation shall be reported to the Department.
(C) (1) The City Council, with respect to highways under its jurisdiction, may also, by ordinance or resolution, prohibit the operation of trucks or other commercial vehicles, or may impose limitations on the weight thereof, on designated highways, which prohibitions and limitations shall be designated by appropriate signs placed on the highways.
(2) Highway commissioners, with respect to roads under their authority, may not permanently post a road or portion thereof at a reduced weight limit unless the decision to do so is made in accordance with § 6-201.22 of the Illinois Highway Code, ILCS Ch. 605, Act 5, § 6-201.22.
(D) The Department shall likewise have authority as hereinbefore granted to the City Council to determine by resolution and to impose restrictions as to the weight of vehicles operated under any highway under the jurisdiction of said Department, and such restrictions shall be effective when signs giving notice thereof are erected upon the highway or portion of any highway affected by such resolution.
(E) When any vehicle is operated in violation of this section, the owner or driver of the vehicle shall be deemed guilty of a violation and either the owner or the driver of the vehicle may be prosecuted for the violation. Any person, firm, or corporation convicted of violating this section shall be fined $50 for any weight exceeding the posted limit up to the axle or gross weight limit allowed a vehicle as provided for in § 74.110(A) or (B) and $75 per every 500 pounds or fraction thereof for any weight exceeding that which is provided for in § 74.110(A) or (B).
(F) The city is authorized to enforce a county weight limit ordinance applying to county highways within its corporate limits and is entitled to the proceeds of any fines collected from the enforcement.
(ILCS Ch. 625, Act 5, § 15-316(a) - (f))