Supplemental maps. The supplemental maps indicated below are hereby adopted and, with others that may hereafter be officially adopted for special purposes indicated, shall have the same force and effect as the Zoning Map and are included as a part of the Zoning Map:

Right-of-way. Where boundaries are indicated in the right-of-way of streets or watercourses, such boundaries shall be the center line of the right-of-way.

Property lines. Where boundaries approximately follow property lines and are not more than 25 feet therefrom, the property line shall be the district boundary.

Parallel to street or road. Where boundaries are parallel to a street or road and are fixed by dimensions on the Zoning Map, the distances shall be measured from the right-of-way line where a plan is on file with the Norfolk County Registry of Deeds or, in the absence of such plan, from a line parallel to and 25 feet from the center line of the traveled way.

Scale. Where distances are not specified on the Zoning Map nor otherwise determined from the above provisions, the scale of the Zoning Map shall be used to determine the location of the district boundary.

Undefined boundaries. The determination of boundaries in question not defined herein or on the Zoning Map shall lie with the Board of Appeals.

Split lots. Where a lot is transected by a zoning district boundary, the regulations of these bylaws applicable to the larger part of the area of such lot may also, at the option of the lot owner, be deemed to govern in the smaller part beyond such zoning district boundary but not to exceed 30 linear feet beyond such zoning district boundary, if the smaller part has frontage on an accepted way.