Flooding happens during heavy rains, when rivers overflow, when ocean waves come onshore, when snow melts too fast or when dams or levees break.
THINGS TO KNOW
Flooding may be only a few inches of water or it may cover a house to the rooftop. Floods that happen very quickly are called flashfloods. Flooding is the most common of all natural hazards. It can happen in every U.S. state and territory.
Important terms to know:
Flood Watch or Flashflood Watch -- Flooding may happen soon. Stay tuned to the radio or television news for more information. If you hear a flashflood warning, talk to an adult immediately!
Flood Warning -- You may be asked to leave the area. A flood may be happening or will be very soon. Tell an adult if you hear a flood warning. If you have to leave the area, remember to bring your Disaster Supply Kit and make arrangements for your pets.
Flashflood Warning -- A flashflood is happening. Get to high ground right away. Tell an adult! by Andres lince
why a flood is flood?
principal types and causes:
Riverine
Slow kinds: Runoff from sustained rainfall or rapid snow melt exceeding the capacity of a river's channel. Causes include heavy rains frommonsoons, hurricanes and tropical depressions, foreign winds and warm rain affecting snow pack. Unexpected drainage obstructions such as landslides, ice, or debris can cause slow flooding upstream of the obstruction.
Fast kinds: include flash floods resulting from convective precipitation (intense thunderstorms) or sudden release from an upstream impoundment created behind a dam, landslide, or glacier.
Caused by a significant and unexpected event e.g. dam breakage, or as a result of another hazard (e.g. earthquake or volcanic eruption).
Muddy
A muddy flood is generated by run off on crop land.
A muddy flood is produced by an accumulation of runoff generated on cropland. Sediments are then detached by runoff and carried as suspended matter or bedload. Muddy runoff is more likely detected when it reaches inhabited areas.
Muddy floods are therefore a hillslope process, and confusion with mudflows produced by mass movements should be avoided.
Other
Floods can occur if water accumulates across an impermeable surface (e.g. from rainfall) and cannot rapidly dissipate (i.e. gentle orientation or low evaporation).
Flooding happens during heavy rains, when rivers overflow, when ocean waves come onshore, when snow melts too fast or when dams or levees break.Important terms to know:
why a flood is flood?
principal types and causes:
RiverineEstuarine
Coastal
Catastrophic
Muddy
- A muddy flood is generated by run off on crop land.
A muddy flood is produced by an accumulation of runoff generated on cropland. Sediments are then detached by runoff and carried as suspended matter or bedload. Muddy runoff is more likely detected when it reaches inhabited areas.Muddy floods are therefore a hillslope process, and confusion with mudflows produced by mass movements should be avoided.
Other