The degree of flood protection sought by the provisions of this article
is considered reasonable for regulatory purposes and is based on acceptable
engineering methods of study. Larger floods may occur on rare occasions.
Flood heights may be increased by man-made or natural causes, such
as ice jams and bridge openings restricted by debris. This article
does not imply that areas outside any identified flood-prone area,
or that land uses permitted within such areas will be free from flooding
or flood damages.