No driveway shall be so constructed or graded as to leave a step, a sharp depression, or other obstruction on the sidewalk. The grade shall be as nearly as possible the same as that of the adjoining sidewalk. It shall be unlawful to have the surface finish of any driveway where the same crosses the sidewalk constructed of such materials as to render it slippery or hazardous to pedestrians, or to have the grade of the portion vary from the grade of the sidewalk, or be other than level.
Penalty, see § 94.999