An early September storm in St. Petersburg, Florida, overwhelmed storm drains and caused widespread flooding across the Tampa Bay area.
Annette Brown was at work when the rain started. She realized something was wrong when the main road to her neighborhood was flooded. She took an alternative route and had to park a few blocks away.
The water poured out when she opened her front door. Nearly everything in her home was destroyed.
"It's just memories that you can't replace. That's the biggest thing for me. It'll take care of itself, but it just makes you feel real vulnerable" Brown said. "You know, you're not the only one going through it. But to be in it now, you can really respect those who have had to go through something like this."
Residents like Brown felt blindsided by the flooding. Their homes aren't in a FEMA special hazard zone.
Nearly 6 million properties and property owners across the U.S. don't know or underestimate their flood risk, according to a 2020study from the nonprofit climate research firm First Street Foundation.
"When people buy their home, they're not required to have flood insurance. There's no local knowledge around 100 year flood zones," said Jeremy Porter, head of climate implications at the First Street Foundation.
Record rainfall events challenging historic norms are the places First Street found the highest levels of unknown risk.
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"One of the places that really pops out in our model — West Virginia. Their primary risk is from heavy precipitation. And that heavy precipitation and small waterways are two sources of flooding that FEMA doesn't capture," said Porter.
FEMA's flood insurance rate maps are the most common reference for flood risk nationwide, but they're often incomplete or outdated.
"They're really good on main river channels. And they're really good on coastal storm surge areas. Outside of those areas, you're going to see a lot of places that don't realize that they have flood risk," said Porter.
FEMA maps were never intended to measure personal flood risks.
"They just set rates and building code requirements. That's it. But that's the thing I think we have to break is, people look at those as flood maps, they don't understand it's an insurance rate map," said Craig Fugate, former FEMA administrator.
FEMA's insurance rate map uses data from past events. It's one of the differences between flood zones in FEMA's maps and First Street's maps. First Street corrects for current conditions and climate change prediction. But it's FEMA's maps that informed our infrastructure.
"The challenge is, especially in the urban areas, is getting stormwater managers to really look at what's the vulnerability in extreme rainfall events, and asking a different question: how much rain does it take before it becomes catastrophic," said Fugate.
Unlike First Street's maps, FEMA maps need to be adopted by local municipalities.
Brown's neighborhood, like most in Florida, was built to handle 7.5 inches of rain over 24 hours. On the day of the flood, rainfall measured nearly 5 inches in just one hour.
"We're actually finding that the one in 100-year rainfall event occurs like once every ten years in some places. Especially in places like the Midwest and the Northeast. That is the type of climate change that's happening in those areas," said Porter.
The northeast saw four record-breaking rain events this summer alone. Places like West Virginia, Idaho and Montana are in the top five states with the highest proportion of properties with flood risk, according to First Street.
It's a national trend. Every region in the country is seeing more rain.
"Summer storms are getting stronger," said Porter. "They're just sitting over places and dumping extreme amounts of precipitation."
First Street's data is publicly available on its website Firststreet.org. Users can type in addresses, cities or communities and see down to individual properties.
"Once you know your risk, I think the more important thing is to understand, what are some solutions that you can do to protect your property," said Porter.
Homeowners like Brown want local leaders to be more proactive.
"The city, our mayor, they need to pay more attention to those things because it puts people out of their home. It costs a lot of money. It depresses people. You know, there's a lot that goes with it," Brown said. "A lot of people around here don't have flood insurance. So. What are they going to do?"
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