In determining the boundaries of districts as shown on the Zoning Map, the following shall apply:
(a) Where zoning district boundaries are indicated as streets, existing lot or property lines, the mean level of water bodies, right-of-way lines of railroads and the city corporation lines, or such lines extended, such lines shall be considered to be such boundaries.
(b) In all cases where a zoning district boundary line divides a lot under single ownership, the Board of Zoning Appeals, upon recommendation by the Planning Commission and request by the landowner that up to fifty (50) feet on either side of the district boundary be rezoned to one (1) of the districts into which it is divided, may order on the basis of hardship, that such a zoning classification be made effective.
(c) Insofar as possible, when preparing new zoning district boundaries, the Planning Commission shall draw such boundaries to coincide with existing lot or property lines, right-of-way lines or the mean level of water bodies, or such lines extended.
(d) In case of uncertainty as to the true location of a zoning district boundary line in a specific case, the determination thereof shall be made by the Zoning Administrator.