An interim report submitted to the Florida Building Commission says that Southwest Florida coastal communities impacted by last September’s Hurricane Ian were “ill-prepared” for the storm surge and flooding, despite lessons on wind mitigation learned from Hurricane Charley 18 years earlier. Ian was the costliest storm in Florida history, killing 156 people and causing an estimated $109.5 billion in damage in Florida. Only an estimated half of that will be covered by insurance.Former Florida Deputy Insurance Commissioner Lisa Miller sat down with the report’s co-author and another extreme events scientist who produced early catastrophic models on Ian for insurance companies. They discussed how this new research shows some of the same patterns of destruction seen in prior storms, that Florida hurricanes are not getting stronger or more frequent, how elderly and poor residents are disproportionately hurt, potential changes to the state building code, and why a new approach to mitigation is needed. Show Notes New lessons are emerging from Hurricane Ian, the high-end Category 4 hurricane that made landfall near Fort Myers Beach on September 28, 2022. An interim report by a team of scientists supported by the Florida Building Commission showed Ian’s tropical storm-force wind field was 2.3 times the diameter of 2004’s Hurricane Charley. The greater resulting storm surge of 13 feet impacted high population areas living in both elevated and on-grade homes along hundreds of miles of canals and coastal frontage. (For full Show Notes, visit https://lisamillerassociates.com/episode-44-dynamic-duo-ian-hit-hard/) Findings: The report evaluates specific building code-related impacts to structural performance, including breakaway walls relative to code provisions, placement of the coastal construction control line, evidence for surge-induced floor slab uplift forces, and performance of common roof cover and wall cladding elements. Dr. David O. Prevatt, one of the report’s co-authors, is a Professor of Civil & Coastal Engineering at the University of Florida’s Herbert Wertheim College of Engineering. He is part of the Structural Extreme Events Reconnaissance (StEER) Network of researchers and product engineers that conducts surveys to assess building performance after each hurricane. Its evaluation was used in the interim report and captured Hurricane Ian’s damage patterns and storm surge. Dr. Prevatt said Ian was not a design level wind-event, meaning its wind speed on land of about 120 mph was below the building code standards of 154-160 mph for Lee County, where it made landfall on September 28, 2022.“The severe damage we saw was really the flooding, in particular the manufactured homes on Fort Myers Beach and mostly older slab-on-grade homes,” said Dr. Prevatt. “The good news, if there is any that we can draw from this, is that recent construction built to the recent Florida Building Code standards performed well, even in areas where they were impacted by the 13-foot high storm surge.”Yet, Ian destroyed or severely damaged about 20,000 homes in a wide path from Lee County on the Gulf Coast and inland across central Florida to Daytona Beach on Florida’s Atlantic Coast. Dr. Prevatt said he saw the same patterns of damage in Ian that he saw in the previous six years from Hurricanes Matthew, Irma, and Michael. “It’s one of the saddest parts for me. If we don't harden our communities or retreat and move them away from these intense events, we will repeat what we've seen here five, 10, 20 years down the road,” said Dr. Prevatt. Dr. Karthik Ramanathan is Vice President of Research at Verisk, the worldwide data analytics and risk assessment firm. He led the catastrophe modeling team that estimated Hurricane Ian’s initial insurance and reinsurance losses at between $42 billion to $57 billion, not including federal flood insurance losses. The firm’s catastrophe or extreme event models not only help insurance companies determine adequate insurance premiums to the assessed value of risk and speed adjusters to the hardest hit areas right after the storm but “can also act as excellent platforms for you to test out the impact of mitigation measures,” said Dr. Ramanathan. “As David said, the performance of manufactured homes or mobile homes continues to be a major issue, even 30 years after Hurricane Andrew, although a lot has been done to strengthen them,” said Dr. Ramanathan. “We saw a colossal amount of damage to manufactured homes. Older and middle aged homes also saw significant damage.” He and his team spent a week in South Florida after Hurricane Ian made landfall, surveying damage in both coastal and inland counties. Some inland counties he noted had “pretty staggering” claim losses similar to coastal counties near Ian’s landfall.“Even on the wind side, some of these inland counties saw a significant amount of...
