Water School

What is a flood plain?

A floodplain is any ordinarily dry land area susceptible to inundation by water. This area is usually low, flat, and next to a stream or other body of water. Living on a floodplain can be especially dangerous in the circumstance that flooding does occur. There is always some risk for those on a floodplain, whether it’s people, businesses, or agriculture. Some floodplains are clearly defined by natural features, by infrastructure made by people, or not clearly outlined.

Some floodplains are extraordinarily wide, while some rivers have narrow floodplains.

In addition to being a natural phenomenon, the Federal Emergency Management Administration legally defines the concept.

FEMA designates floodplains nationwide for several reasons:

  • To set rates for flood insurance.
  • Mortgage issuers usually require flood insurance for any property in the designated floodplain.
  • Cities set special building regulations for properties inside the designated floodplain.
  • Models based on designated floodplains can be used to warn residents of impending flooding and to issue evacuation orders.

If you think your property might be on a floodplain, you can find out on the Federal Emergency Management Administration website here

Return to Water School to learn more about water!

floodplain | National Geographic Society
How Do I Find out If Property Is in a Flood Plain? (sfgate.com)
Flood Maps | FEMA.gov
Texas Capitol




The information provided on this site is intended as background on water within the Brazos River basin. There should be no expectation that this information is all encompassing, complete or in any way examines every aspect of this very complex natural resource.

If you have questions about a post or would like additional information, please contact us or call 888-922-6272.

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