Any person hauling any loose material over the streets of the city shall do so in a tight box or container (to include beds of trucks) properly covered so that such material shall not sift from, bounce, escape or be blown out of the carrying vehicle or permitted to fall upon public property as defined herein; and whenever loading or unloading of any loose material, including lumber or wood, the same shall fall upon the public property it shall be promptly and completely removed from such public property to the satisfaction of the city engineer. (Ord. 152 §2, 1970).