Water School

What is a 500-year flood?

A 500-year flood is a high streamflow that overflows the natural or artificial banks of a waterway and has a two-tenths of 1% chance of occurring in any given year.




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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