FLOOD STAGE: The elevation or stage at which overflow of
the natural banks of a stream begins to cause damage or begins to
present a potential flood-damage hazard in the reach in which the
elevation is measured.
BANKFULL STAGE: The elevation or stage of the lowest natural
banks of a stream or river within the reach in which the water is
measured.
RIVER GAGE DATUM: The elevation above a chosen datum corresponding
to the zero reading of the river gage.
FORECAST POINTS: Designated gage sites the River Forecast
Center (RFC) uses to make detailed forecasts. These forecasts include
current stage, forecast crest, and expected trends. Not all gage
sites are forecast sites.
FlOOD: The inundation of a normally dry area caused by an
increased water level in an established watercourse, such as a river
or stream, or drainage ditch or ponding of water at or near the
point where rain fell.
FLASH FLOOD: A flood which is caused by heavy or excessive
rain in a short period of time, generally less than six hours. Also,
at times a dam failure can cause a flash flood, depending on the
type of demand time period during which the break occurs.
URBAN & SMALL STREAM FLOODING: Flooding of small streams,
streets and low lying areas, such as railroad underpasses and urban
storm drains. This type of flooding is mainly an inconvience and
is generally not life threatenting nor is it significantly damaging
to property.