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Water-Related News

Decades-old maps don’t fully capture Central Florida’s flooding risk

Flooding can be tough to predict. For Central Florida communities relying on official flood maps that are almost 20 years old, it can be even more difficult.

A lot has changed in two decades, and the Federal Emergency Management Agency’s (FEMA) flood maps don’t fully account for all those changes: like development, stormwater infrastructure, and climate change.

But importantly, the scope of FEMA flood maps is limited to begin with. The maps are designed primarily to illustrate where one, specific type of flood is most likely to occur: the 100-year flood.

Also called a Special Flood Hazard Area or SFHA, the 100-year floodplain is an area with at least a 1% chance of flooding each year. But it’s a bit of a deceptive term, according to Seminole County Public Works Project Manager Jeff Sloman.

“What's called a 100-year flood, is defined as a storm event that, statistically, has a 1% chance of occurring every year. It's not a storm that occurs every hundred years,” Sloman said.

In fact, in the last five years alone, nearly half of U.S. counties experienced a flood event, according to FEMA. And nationally, 40% of flood insurance claims come from outside the 100-year floodplain.

“Binary views, the ‘in or out’ of a flood zone, can lead to the misconception that properties outside of the FEMA flood zone are safe from flooding,” a FEMA spokesperson wrote in an email to Central Florida Public Media. “There is no such thing as a ‘no-risk zone.’”