n.
High-water stage in which water overflows its natural or artificial banks onto normally dry land, such as a river inundating its floodplain.
Uncontrollable floods likely to cause considerable damage commonly result from excessive rainfall in a brief period, but they may also result from ice jams during the spring rise in rivers, and from tsunamis . Common measures of flood control include improving channels, constructing protective levees and storage reservoirs, and implementing programs of soil and forest conservation to retard and absorb runoff from storms.