The area of a ﬂat valley ﬂoor that a river, swollen by spring melt and spring rains in some parts of the country, and by hurricanes and tropical storms in others, will cover when it overﬂows its usual course or banks is its ﬂoodplain. It is an area in which you will probably not be able to buy ﬂood insurance from a private company. Floodplain incursions are measured according to a river’s history—a variety of frequencies depending on the region’s hydrology and the upstream control by dams. The hundred-year ﬂoodplain is inundated once a century; the one-year ﬂoodplain, annually. The means of managing ﬂoodplain regions includes dikes, ﬂoodways, and zoning and building codes—these regulated by community or state law, unless they do not meet federal government, especially Federal Emergency Management Agency (FEMA), minimum standards; then federal law applies.