It shall be the duty of the occupant or occupants of the ground floor of any business house or mercantile establishment in the city to keep clean and clear, the space in the rear of any such lot, house or mercantile establishment, between the rear of the building and the alley line, including all filth, sewage, sweeping, dung, papers, boxes, ashes, lumber, kindling, wood, glass, weeds, vegetables, slops, litter of any kind, except as to such refuse or filth deposited by other occupants of the building. In all cases, it shall be the duty of all occupants of any building in the city to cause the matter set forth in this chapter to be collected and removed in accordance therewith. (Prior code § 9-211)