(1) Boundaries indicated as approximately following the centerlines of streets, highways or alleys shall be construed to follow such centerlines.

(2) Boundaries indicated as approximately following platted lot lines shall be construed as following such lot lines.

(3) Boundaries indicated as approximately following the city limits shall be construed as following the city limits.

(4) Boundaries indicated as following a shoreline or bulkhead line shall be construed to follow such shoreline or bulkhead line and, if change in the shoreline or bulkhead line occurs, shall be construed as following the original shoreline or bulkhead line; boundaries indicated as approximately following the centerlines of streams, rivers, canals, lakes or other bodies of water shall be construed to follow such centerlines.

(5) Boundaries indicated as parallel to or extensions of features indicated in subsections (1) through (4) of this section shall be so construed. Distances not specifically indicated on the official zoning map shall be determined by the scale of the map.

(6) If the actual location of physical features varies from those shown on the official zoning map or in other circumstances not covered by subsections (1) through (4) of this section, the board of adjustment shall interpret the district boundaries.