It shall be the duty of every person using or occupying in any manner or for any purpose whatsoever any house, store, shop or tenement of any kind, and all persons having charge of churches and public buildings of every description, and the  owners of unoccupied houses and unimproved lots situated on any paved street in the City, and of their agents, within three hours in a business area and within ten hours in a residential area, after the fall of any snow, unless the snow shall have fallen between the hours of 6:00 p.m. and 6:00 a.m. of the following morning in which case it shall be removed before 11:00 a.m. in a business area and before 6:00 p.m. in a residential area, or in the case of the formation of any ice on the sidewalk, to remove or clear the  same away, or cause the same to be removed or cleared away from the sidewalks fronting the residences, stores, houses, churches, stables, buildings or lots so used, occupied or owned by them or under their charge, in such manner as to leave the sidewalk clean and free from snow and ice, and in such manner as not to obstruct the passage of the water in the gutters. It shall further be the duty of such persons or their agents to keep the gutters leading to the sidewalks situated in the front or at the rear or side of such tenements  above named free from snow and ice and every obstruction, and free from dirt, trash and filth. (1967 Code §19-8)