The provisions of this chapter do not require any changes or improvements to be made to lawfully existing structures. However, when an improvement is made to any existing structure, the provisions of §
145-31 shall apply.
The following provisions shall apply whenever
any improvement is made to an existing structure located within any
identified floodplain area:
A. No expansion or enlargement of an existing structure
shall be allowed within any floodway area that would cause any increase
in the elevation of the one-hundred-year flood.
B. No expansion or enlargement of an existing structure
shall be allowed within any area that would, together with all other
existing and anticipated development, increase the one-hundred-year
flood elevation more than one foot at any point.
C. Any modification, alteration, reconstruction, or improvement,
of any kind to an existing structure, to an extent or amount of 50%
or more of its market value, shall constitute a substantial improvement
and shall be undertaken only in full compliance with the provisions
of this chapter.
D. Any modification, alteration, reconstruction, or improvement
of any kind to an existing structure, to an extent or amount of less
than 50% of its market value, shall be elevated and/or floodproofed
to the greatest extent possible.