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.

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