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The Trump administration called the July Fourth Guadalupe River flooding a "100-," "500-" or "1,000-year flood" during a Friday visit to Kerrville, prompting questions about the meaning of the term.
It is not unheard of to have multiple “100-year floods” or "1,000-year floods” in the same year, says John Nielsen-Gammon, the Texas state climatologist.
As we continue to grieve the loss of so many Hill Country flood victims, there is a lot of information being thrown around. KSAT wants to remind people what a “100-year flood” actually means.
After nine years, repair work continues on the Columbia Canal. On the anniversary of the 1,000-year flood that damaged the canal, City of Columbia leaders gave an update on several major projects ...
A 500-year flood means such an event has a 1 in 500 chance, or 0.2 percent, of occurring in a year. Another concept scientists use is how frequently an event of a certain intensity is expected.
If you live in a 1-percent AEP (100-year) flood zone, writes USGS, the odds of being flooded at least once over a 30-year mortgage are 26%. That's about a 1 in 4 chance.
If you live in a 1-percent AEP (100-year) flood zone, writes USGS, the odds of being flooded at least once over a 30-year mortgage are 26%. That's about a 1 in 4 chance.
A "100-year flood" means a 1% chance of that level of flooding happening each year. Houston saw three 500-year flood events within three years from 2015 to 2017, including Hurricane Harvey.
So no, a 100-year flood doesn't mean it can only happen once in a century. And with all the bayous, creeks and rivers in the area, our experts say don't be overconfident.
The Brief. A "100-year flood" means a 1% chance of that level of flooding happening each year. Houston saw three 500-year flood events within three years from 2015 to 2017, including Hurricane Harvey.
CHARLOTTE, N.C. — When forecasters warn about a 100-year or 500-year flood, it doesn’t mean it only happens once every century.