Flooding typically occurs when prolonged rain falls over several days, when intense rain falls over a short period of time, or when an ice or debris jam causes a river or stream to overflow onto the surrounding area.

Flooding in Hamburg, Iowa, in 2019.
Flooding in Hamburg, Iowa, in 2019.

A flood is the most common natural disaster in the world. Floods can happen during heavy rains, when snow melts quickly, or when dams or levees break.

Flash floods are the most dangerous kind of floods, because they combine the destructive power of a flood with extraordinary speed. Flash floods occur when heavy rainfall exceeds the ability of the ground to absorb it.           

You should be aware of flood hazards no matter where you live, but especially if you live in a low-lying area, near water or downstream from a dam. Even very small streams, gullies, creeks, culverts, dry streambeds, or low-lying ground that appear harmless in dry weather can flood. Every state is at risk for flooding.

Flood mitigation

Mitigation includes any activities that prevent an emergency, reduce the chance of an emergency happening, or lessen the damaging effects of unavoidable emergencies. Investing in mitigation steps now such as constructing levees and purchasing flood insurance will help reduce the amount of structural damage to your home and financial loss from building and crop damage should a flood or flash flood occur.

What to do before, during and after a flood

Iowa Disaster History - Iowa Flood of 1993

The Great Flood of 1993

17

fatalities

10,000

people evacuated

21,000

homes damaged or destroyed

$2.7B

in damage

Iowa Disaster History

Great Flood of 1993

The flood of 1993 is one of the most defining natural disasters in Iowa history. When President Clinton surveyed the damage he stated, “I have never seen anything on this scale before." Video: KCCI 8