A structure or use of a structure or premises which lawfully existed before the enactment of these provisions but which is not in conformity with these provisions may be continued, subject to the following conditions:
A.
Existing structures and/or uses located in any Floodway District shall not be expanded or enlarged (unless the effect of the proposed expansion or enlargement of flood heights is fully offset by accompanying improvements).
B.
Any modification, alteration, repair, reconstruction or improvement of any kind to a structure and/or use located in any floodplain district to an extent or amount of less than 50% of its market value shall be elevated and/or floodproofed to the greatest extent possible regardless of its location in the floodplain district.
C.
The modification alteration, repair, reconstruction or improvement of any kind to a structure and/or use regardless of its location in a floodplain district to an extent or amount of 50% or more of its market value shall be undertaken only in full compliance with the provisions of this and any other applicable ordinance.
D.
Uses or adjuncts thereof which are or become nuisances shall not be permitted to continue.