Flooding can result in extensive and expensive damage. The Pew Charitable Trusts indicate that at least one flood event has occurred on nearly 300 days per year each year since 2000 in the United States.
That's almost a flood a day. Statista reports there were 170 flood disaster events recorded worldwide in 2023. The Center for Disaster Philanthropy indicates there have been 44 floods in the U.S. between 1980 to October 2024, with each resulting in more than a billion dollars in damage.
Considering how catastrophic floods can be, people may wonder what contributes to these events and if there is anything they can do to prevent them. An understanding of flooding can help anyone respond more effectively should a flood occur.
What is a flood?
Flooding occurs when an overflow of water finds its way onto land that is normally dry, says the National Severe Storms Laboratory of the National Oceanic and Atmospheric Administration. Damaging floods may occur with only a few inches of water, or flooding may be so severe, it can cover a house to the rooftop.
The NOAA says floods are the most common and widespread of all weather-related natural disasters.
What causes floods?
Many different situations can cause flooding. The main types are:
• Melting snow and ice
• Dams or levees breaking
• Storm surges, resulting in ocean waves coming ashore
• Heavy rainfall
• Geography, such as locations that are near rivers
How does urbanization impact flooding?
As land is increasingly converted from fields and woodlands to developed areas, it loses the ability to absorb rainfall, according to officials with the city of Brownsville, Texas. Urbanization can increase runoff two to six times over what would occur on natural terrain.
Urban areas are at higher risk for floods because rooftops divert rain to the ground below, which is comprised of cement and paved surfaces that prevent the ground from absorbing rain.
What is a flash flood?
Some flooding can be anticipated, but flash floods often happen with little to no warning, says the NOAA. They occur when there is more rain than the soil can absorb. This extra water quickly flows into rivers and creeks and can overwhelm storm drains.
Flash floods can be the most dangerous kind of floods because they feature fast-moving flood waters. Flash flooding can affect an area within minutes. Densely populated areas are often at the highest risk for flash floods because these urban areas cannot absorb the rain and water runoff effectively.
What can I do in the event of a flood?
People can take certain precautions if flood conditions are anticipated.
• Listen to local media for flood watches and warnings.
• Know the evacuation zone and route, and evacuate if prompted.
• Have a 'grab bag' ready with essential items.
• Seek higher ground, which could be the highest floor of the home.
• Do not drive, walk or try to swim through floodwaters. Even shallow moving water can sweep a person away.
• Water can conduct electricity, so stay away from downed electrical wires.
• Use a stick to check the depth first if you must walk in flood water.
• Turn off and disconnect appliances and utilities, if advised.
• Remain away from damaged areas until officials have officially cleared them for return.
• Consider purchasing flood insurance as homeowner's insurance policies typically do not cover flood damage.
Staying alert, prepared and safe during floods is vital.

(Photo: Spectators watch as Cross Creek floods in Fayetteville in 2018. Photo courtesy of Flickr)