Wave overtops a sand berm at Hartlepool, UK. HR Wallingford / floodsite.net

By EVAN LEHMANN of ClimateWire
22 July 2011 CHICAGO — A three-year study to determine the possible impacts of climate change on federal flood insurance will warn of huge increases to the amount of land that could be inundated by rising sea levels, heavier downpours and stormier coastlines. The size of the nation’s flood plains is expected to grow by 40 or 45 percent over the next 90 years, says the study, which is scheduled to be released later this summer. That prediction envisions waves of seawater pushing deeper inland during strengthening storms as oceans rise between 0.75 and 1.9 meters by the year 2100. In river valleys and other low-lying flow ways, more rainwater could routinely reach onto areas where current flooding is rare. Stretching the flood plains could encircle millions of new homes and businesses and expand the National Flood Insurance Program (NFIP) beyond its current volume of 5.6 million policies that protect property valued at $1.2 trillion from water damage. The study estimates that the program’s policies could double in number by century’s end. Those results pushed Mark Crowell, a geologist with the Federal Emergency Management Agency who is overseeing the study, to tell coastal professionals attending a conference here this week that the findings establish “a need for FEMA to incorporate the effects of climate change more directly into various aspects of the NFIP.” […] But flood insurance experts were struck by the sheer size of the potential flood plain expansion, which could increase the amount of land prone to flooding by almost half of its current size. “It’s a big number,” said Michael Buckley, a former FEMA official who works on flood issues. […] Earlier calls went largely unanswered by Congress and policymakers. The first warning came 20 years ago, when FEMA undertook a congressionally directed study on sea level rise, reviewing impacts of 1- to 3-foot increases. Later in the 1990s, the agency studied future coastal erosion, which is enhanced by rising seas. Congress, facing opposition from developers, decided more research was needed, culminating in a major report by the Heinz Center. It recommended that Congress require FEMA to make maps of future coastal erosion and raise insurance rates to reflect rising risk. The newest alert should be heeded, says David Maurstad, who ran the insurance program under President George W. Bush. “We’ve got to start managing these issues now. We can’t wait for that to happen,” he said of the rising damage associated with climate change. “We can’t let the built environment continue to increase in these risky areas.”

Flood-Prone Land Likely to Increase by 45% — a Major Challenge to Federal Insurance Program