Flooding facts:
On average, 114 people die in the USA because of flooding.
Flooding causes more damage in the US than any other severe weather event.
More damage can happen after a flood. As water recedes, there can be hazards such as contaminated soil, fuel, untreated sewage and sharp objects left behind. Mold can grow quickly.
Flash floods can happen quickly and without much warning.
More than half of all flood related deaths are due to individuals walking or driving into floodwaters.
Definitions
A flash flood is rapid flooding caused by a few different things including heavy rains, a dam break (man made dam or ice jam break), etc. Saturated soil and heavy rains result in water needing to go somewhere and depending on the landscape and topography, flash flooding can occur. The flash flood can occur within minutes up to 6 hours after the heavy rainfall and does not usually last long.
A flood is an overflow of water onto normally dry land and can last for days or weeks. It is caused by a number of things such as high amounts of rainfall and snow melt.
Areal Flooding is gradual flooding in areas not typically covered by water usually caused by prolonged and persistent moderate to heavy rainfall. Gradual ponding and build up of water in low-lying areas can be expected. Even though areal flooding develops slower than flash flooding, it can still be a threat and should be taken seriously.
Flood stageis when a body of water like a river rises to a level that begins to be a hazard to lives and property.
River or Flood Crest is the highest level a river will reach before it goes back down.
Flash Flood Watch or Flood Watch means flooding of some type is possible in the designated watch area so be on the alert.
Flash Flood Warning or Flood Warning mean flooding has been reported or is imminent so take the necessary precautions immediately. Get to high ground as soon as possible.
Urban and Small Stream Advisory means flooding of small streams ,streets and low lying areas and storm drains is occurring.
River Flooding. Once a river reaches flood stage, the flood severity categories used by the River Forecast Centers include minor flooding, moderate flooding, and major flooding. Each category has a definition based on property damage and public threat. This applies to large scale river flooding:
Minor Flooding—minimal or no property damage, but possibly some public threat or inconvenience
Moderate Flooding—some inundation of structures and roads near streams. Some evacuations of people and/or transfer of property to higher elevations are necessary.
Major Flooding—extensive inundation of structures and roads. Significant evacuations of people and/or transfer of property to higher elevations.
Flood Safety
