FLOODSTAGE
Flood stage
Flood stage is the level at which the surface of a river, stream, ocean, or other body of water has risen to a sufficient level to cause sufficient inundation of areas not normally covered by water to cause an inconvenience or a threat to life and property. When a body of water rises to this level, it is considered a flood event. Flood stage does not apply to areal flooding. Because areal flooding occurs by definition over areas not normally covered by water, any water at all creates a flood. Usually, Moderate and Major stages are not defined for areal floodplains.The above text is a snippet from Wikipedia: Flood stage
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