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