First Street finds most Debby-damaged homes outside the flood zone with no coverage

More than three-quarters of the properties flooded by Hurricane Debby were outside a designated flood hazard area and were likely uninsured for water loss. Many of these properties were concentrated in places apparently far from where the storm made landfall, including Sarasota, Florida; Savannah, Georgia; and Charleston, South Carolina.

That was the conclusion of a report by the First Street Foundation, a nonprofit that uses computer modeling and loss data to assess risk from climate change and storm events.

“Losses from Hurricane Debby were disproportionately concentrated in the state of Florida,” the Aug. 12 report said. “First Street flood model simulation results found $2.6 – $4.5 billion in losses from the event, of which $1.9 – $3.3 billion (~70%) are likely uninsured” and occurred in outside the FEMA Special Flood Hazard Area.

Overall, the storm, which made landfall as only a Category 1 hurricane in the Big Bend portion of Florida, caused up to $12 billion in damage, with about $9.7 billion outside of FEMA’s designated flood zones , the report shows. About 385,000 properties saw a water level that reached the building footprint. About 160,000 of those likely suffered damage, First Street reported.

“These findings highlight the need for a re-evaluation of flood risk assessments and preparedness strategies in vulnerable areas,” the report said.

Other reports noted that relatively few properties in the area were covered by private or National Flood Insurance Program policies. NFIP data shows that the number of flood policies in South Carolina, for example, fell 1.4 percent over the past year, The Charleston Post and Courier reported.

“As Debby moved inland, the storm’s slow pace allowed it to drop significant amounts of rain across the southeastern United States,” First Street said. “This led to catastrophic flooding, particularly in parts of Georgia and South Carolina, where several rivers overflowed their banks.”

One area that was unexpectedly hard hit by the flood was Bradenton, Florida, south of Tampa. As the waters rose to 48 feet behind the Manatee River Dam, local officials made the decision to release the pressure to avoid disaster. But the release caused significant flooding downstream and led to more than 200 water rescues, the report said.

The full report can be accessed here.

Top photo: Ann Farkas surveys her flood-damaged home in Canisteo, New York, after the remnants of Tropical Storm Debby moved through the area, creating flash flooding conditions. (AP Photo/Craig Ruttle)

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