The order, described by senior administration officials, represents a major shift for the federal government: while the Federal Emergency Management Administration published a memo three years ago saying it would take global warming into account when preparing for more severe storms, most agencies continue to rely on historic data rather than future projections for building projects.
The new standard gives agencies three options for establishing the flood elevation and hazard area they use in siting, design, and construction of federal projects. 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.
The White House move comes just days after the U.S. Army Corps of Engineers released a massive post-Sandy report examining flood risks for 31,200 miles of the north Atlantic coast. The research explicitly took sea level rise induced by climate change into account, and finds that “Flood risk is increasing for coastal populations and supporting infrastructure.”