Flooding, Not Wind, Poses the Most Risk from Hurricanes

Hurricane Ian was a Category 4 storm that planted itself over Florida and graced the state with as much as 20 inches of rain. More than 100 people lost their lives, and Ian’s effects will be felt until at least Thanksgiving as flooding continues.

The storm surge was as high as 10 feet, razing homes and destroying bridges, and leaving people without shelter. It has become a common refrain: With climate change, the continued, even worsening threat from flooding will continue to accompany hurricanes as will the death and destruction. Experts say more education about flooding from hurricanes is necessary, as is the public’s willingness to head the warnings.

“It isn’t talked about as much in the news. It’s usually about, ‘Oh the winds are going to this and that and peak gusts will be this or that,’ and people just don’t take floodwaters very seriously,” said Mark Hoekzema, chief meteorologist and director of meteorological operations at Earth Networks under AEM, an environmental technology provider.

The National Weather Service has been putting out alerts about possible flooding for a couple of decades, and local governments warn of localized flooding. But often it’s the threat of the high winds that gets people’s attention, unfortunately. The St. Johns River in Florida has already flooded more than 100 homes since Ian hit, and that number will climb.

Climate change and the increased buildup of communities with more pavement and more people are only making things worse.

“You get all this build-up of communities and it’s paved, and the water gets moving into drainage areas, and there’s less square footage that is going to absorb the rain in the traditional way,” Hoekzema said. “It’s going to run off into the rivers where it can erode banks and take out bridges. And then people don’t understand how strong moving water is.”

Most people don’t realize how difficult it is to stand up in knee-deep water, and trying to do so can be lethal. And despite campaigns and warnings such as “Turn Around, Don’t Drown,” people continue to try to drive through flooded areas. It takes just about a foot of water to float most vehicles.

Continued education to get people to pay more attention to flooding is the key.

“Just continually beating people over the heads with making preparations, don’t go near flooded streams, all kinds of things that people do when they are threatened by flooding,” Hoekzema said. “They don’t think things through and make bad decisions, unfortunately.”

There are mitigation options for local governments to implement, like zoning limits or retaining more wetlands to absorb some of the water, and having drainage ponds to collect water. There are alerting products too that warn the public of impending flooding or where not to go.

But the problem isn’t going away.

Climate models have indicated that for every degree of warming, the amount of moisture in the atmosphere will go up about 7 percent. That can add up to another inch or two of water over a couple days of a storm.

“You end up getting the potential for these storms to have greater amounts of rain and increases in damage and threats to people because there are just more people too,” Hoekzema said.