It shall be unlawful for the operator of any school bus, semi-truck consisting of a tractor and trailer, or any motor vehicle with an overall length of more than 27 feet to stop or park any such vehicle on a street within the “Business District”, except to load or unload. Vehicles may stop or stand for a period of time not to exceed what is reasonably necessary to load or unload, and shall be parked in the direction of the traffic flow. It shall be unlawful for the operator of any truck, regardless of length, to park said vehicle within a street intersection, on a crosswalk, in front of a private driveway or on a sidewalk. The City Council may, by resolution, provide truck-parking areas adjoining or adjacent to the business district, and when such parking areas are provided, it shall be the duty of all truck operators to use such parking areas for all parking purposes.