Sec. 9-4.305.  Uncertainty of zone boundaries.
   Where uncertainty exists as to the boundaries of any zone as shown on any zoning map, or part thereof, the following rules of construction shall apply:
   (a)   Where such boundaries are indicated as approximately following street and alley lines or lot lines, such lines shall be construed to be such boundaries.
   (b)   In the case of unsubdivided property and where a zone boundary divides a lot, the locations of such boundaries, unless the same are indicated by dimensions, shall be determined by the use of the scale appearing on such zoning map.
   (c)   Where a public street or alley is officially vacated or abandoned, the zoning regulations applicable to abutting property on each side of the center line shall apply up to the center line of such vacated or abandoned street or alley on each respective side thereof.
   The Commission shall determine such uncertainties.
(§ 8116, T.O.O.C.)