When any driveway crosses the sidewalk of any street or alley within the City for the purpose of passing to and from such street or alley to any lot or building, it shall be the duty, and it is hereby required, upon notice from the Director of Public Works, that the owners of lots abutting or adjoining such street shall pave and curb the same, at their own expense, in such manner as the Director shall require, and keep the same in repair.