Report: Storm Surge Could Cost U.S. Hundreds of Billions

By Andrew Freedman

A new analysis highlights the enormous exposure the U.S. has to storm surge-related impacts, which is one of the most significant hazards posed by a land-falling hurricane. The report from CoreLogic, a private company that provides financial and property information for risk management, shows that for the country as a whole, more than 4 million residential structures are at risk from storm surge flooding in a worst-case scenario storm, with a total estimated price tag of $710 billion. The report ranks New York City and Long Island as the most at-risk metropolitan area, where a Category 4 storm could inflict damage to residential homes of up to $168 billion.

“Even a Category 1 hurricane or low-level tropical storm can wreak billions of dollars of destruction on cities and states many might have previously assumed to be safe from the strong winds and floods of hurricane events,” the report said. “Millions of homes are in fact at risk, from Maine to the southernmost tip of Florida, facing hundreds of billions of dollars in residential property damage.”

A storm surge from Hurricane Irene batters Montauk, New York in August, 2011.

Although it is not discussed in the CoreLogic report, sea level rise from global warming and land elevation changes is already making it easier for damaging storm surge flooding to take place, even during weaker hurricanes.

The CoreLogic analysis shows that although New York City and neighboring Long Island are not at the greatest risk of a hurricane (Miami has a far greater likelihood of getting hit), a powerful hurricane striking the Big Apple would prove to more expensive. The report finds that even a Category 1 storm could cause property damage of $48 billion.

The report shows that the New York residential areas that could be most affected by a storm surge include Beach Haven, West Islip, Massapequa, Riverhead, and part of of Brooklyn.

The CoreLogic report only considers the exposure of single-family residential homes, which means it doesn’t even analyze the value of all the office towers in Lower Manhattan or the New York City subway system. The New York subway system is extremely vulnerable to coastal flooding, which is why it was completely shut down ahead of Tropical Storm Irene in 2011.

The report also uses a worst-case scenario to arrive at its conclusions, meaning that each hypothetical hurricane would hit land at its peak strength, at the time of high tide, etc.

CoreLogic ranked Virginia Beach, Va. second on the list of metro areas with the most expensive price tags from a worst-case storm surge scenario, where a storm could inflict a total of $46 billion in property damage. Miami, New Orleans, Tampa, Boston and Houston round out the top seven metro areas on the list.

Area of Norfolk, Va. like will likely flood from 5 feet of sea level rise. Credit: Surging Seas.

A state-by-state breakdown of residential property exposure to storm surge flooding shows that Florida has the most at-risk real estate — $188 billion worth, followed by New York, New Jersey, and Louisiana.

The new report comes just days after Climate Central published its list of the Top 5 most hurricane prone cities in the U.S., which was based, in part, on exposure to storm surge flooding, but took several other factors into account. Climate Central ranked Tampa-St. Petersburg, Fla., as the most vulnerable city, in large part because the city is extremely exposed to storm surge flooding from Tampa Bay and has not had a major hurricane make a direct hit since 1921.