Federal Flood Maps Are Outdated Because of Climate Change, FEMA Director Says

The maps don’t take into account intense rainfall events, like those plaguing many parts of the country this summer

Flooding near Yellowstone
Flooding in Livingston, Montana, in June Photo by William Campbell / Getty Images

To help keep residents safe and minimize damage to homes and businesses, the Federal Emergency Management Agency (FEMA) maintains nationwide maps that indicate the risk of flooding in various areas.

But human-caused climate change has thrown a wrench into those maps. Record rainfall events are becoming more common and they’re causing unexpected levels of flooding in places that aren’t marked as vulnerable in FEMA’s guidance.

The organization’s director, Deanne Criswell, admitted as much during an interview on CNN’s State of the Union on Sunday.

“FEMA's maps right now are really focused on riverine flooding and coastal flooding,” she told CNN’s Dana Bash on the program. “When we're seeing these record rainfalls that are happening… that's what our flood maps don't necessarily take into consideration.”

Asked whether FEMA plans to update these maps in response to the evolving climate, Criswell confirmed that federal disaster officials would “continue to work with all of our local jurisdictions to help them better identify what their needs are and help them create better predictive models.” She didn’t elaborate on when or how any updates to the maps would occur.

“It's hard to predict when we're going to see rain events like that, right, and the status of the infrastructure to be able to support that,” she said to CNN, adding that the country needs to “start thinking about what the threats are going to be in the future as a result of climate change” in order to mitigate them.

Criswell’s comments came after she visited Jackson, Mississippi, where more than 180,000 residents have been without drinking water since late August because of flood damage caused by intense rainfall.

Other communities, too, have suffered because of flooding this year. On Sunday, the governor of Georgia declared a state of emergency after excessive rainfall flooded homes, cars and streets in the northwestern part of the state. Floods have also hit St. Louis, Yellowstone, Death Valley, Kentucky, DallasIllinois and parts of the Southwest this summer.

Cars covered in debris
Debris from flash flooding buried or trapped about 60 vehicles at Death Valley National Park in August. NPS

As the maps are drawn now, FEMA considers some 8.7 million properties to be located within flood hazard areas. But according to 2020 modeling by the nonprofit First Street Foundation, as many as 14.6 million properties could actually be at a high risk of floods. That means roughly 6 million property owners may not understand their region’s risk and consequently may be underinsured. The nonprofit predicts the number of properties prone to flooding will grow to 16.2 million by 2050 because of climate change.

Without good flood maps, communities that use FEMA’s guidance to determine where it’s safe to construct buildings and other infrastructure are operating with inaccurate information. Likewise, mortgage lenders are using outdated maps to calculate how much property owners need to pay for flood insurance.

Last fall, FEMA updated its risk rating methodology for determining flood insurance prices, a change that has led to more expensive premiums for an estimated 3 million homeowners. Hundreds of thousands of homeowners have dropped flood insurance since FEMA made the change in October 2021, at a time when “it is more important than ever for people living in flood zones to buy insurance,” as Lylla Younes writes for Grist.

FEMA, for its part, has “warned for years that people who live outside of a designated flood zone are nonetheless susceptible to flooding” as Thomas Frank wrote for E&E News last month.

Still, as climate change continues to make flooding worse, “information and transparency for consumers and home buyers and renters about flood risk is critical, no matter where it comes from,” as Laura Lightbody, the flood-prepared communities project director at the Pew Charitable Trusts, told the Washington Post’s Andrew Freedman, Brady Dennis and Laris Karklis in June 2020.