More than fifty percent of Americans live in coastal counties, where key infrastructure and evacuation routes are increasingly vulnerable to things like higher sea levels, storm surges and flooding. In 2013, Climate Central released a report on sea level rise that showed there was about $156 billion worth of property and 300,000 homes, on 2,120 square miles of land that is less than three feet above the high tide line in Florida. The National Climate Assessment found that more than $1 trillion of property and structures in the U.S. are at risk of inundation from sea level rise of two feet above current sea level, an elevation that could be reached by 2050.
The cost of flooding is big for communities and taxpayers. In 2012, Hurricane Sandy hit the Northeast. High winds and coastal storm surge devastated the area causing damages with an estimated cost of $67 billion. Between 1980 and 2013, the United States suffered more than $260 billion in flood related damages.
The President’s Hurricane Sandy Rebuilding Task Force recommended in 2013 that the Federal government create a national flood risk standard for Federally funded projects. In January, President Obama signed an Executive Order establishing a flood standard that will reduce the risk and cost of future flood disasters by requiring all Federal investments in and affecting floodplains to meet higher flood risk standards. The order would require that Federally funded buildings, roads and other infrastructure are constructed to better withstand the impacts of flooding.
This is a major shift for the Federal government. Most agencies have relied on historic data rather than future projections on global warming for building projects. A White House press release stated that the new standard gives agencies the flexibility to select one of three approaches for establishing the flood elevation and hazard area they use in siting, design and construction. They can:
• Use data and methods informed by best available, actionable climate science;
• Build two feet above the 100 year flood elevation for standard projects, and three feet above for critical buildings like hospitals and evacuation centers; or
• Build to the 500 year flood elevation.