Coastal infrastructureProjects using federal funds to adopt siting, building codes informed by sea-level rise

The U.S. Army Corps of Engineers recently released a post-Superstorm Sandy report examining flood risks along 31,200 miles of the North Atlantic coast. Taking into account the effects of climate change on sea-level rise, the report concluded that “flood risk is increasing for coastal populations and supporting infrastructure.” Another report, by the National Oceanic and Atmospheric Administration (NOAA) predicts that coastal communities will experience thirty or more days of flooding by 2050 due to sea-level rise.

These threats notwithstanding, more than half of the U.S. population continues to live in coastal counties and, according to the U.S.National Climate Assessment, more than $1 trillion of property and structures in the United States are at risk of inundation from sea-level rise of two feet above current sea level.

Following remarks about climate change in his recent State of the Union speech, President Barack Obama issued an executive order last week directing federal, state, and local government agencies, using federal funds, to adopt stricter building and siting standards to reflect scientific projections that future flooding will be more intense and frequent due to climate change. This is not the first time the Obama administration has required federal projects to reflect sea-level projections. Post-Superstorm Sandy, the Federal Emergency Management Agency (FEMA) and theHousing and Urban Development Department  (HUD) developed updated elevation standards for New York, New Jersey, Connecticut, Maryland, and Rhode Island based on climate change projections, and required any approved projects to reflect those projections or local elevation requirements if they were tougher.

Obama’s executive order gives agencies three options for establishing the flood elevation and hazard area they use when constructing federally-backed projects. Agencies 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 such as hospitals and utilities; or build to the 500-year flood elevation.

The Washington Post reports that more than 350 state and local governments have already adopted flood and building standards which fall in line with the executive order’s requirements. For example, residents of Perdido Beach, Alabama, a small waterfront community of 581 people, in 2010 adopted an ordinance requiring that any new construction be built three feet above the 100-year flood elevation for a standard project. “We know these events are going to come, and we want to be prepared for them,” said Mayor Patsy Parker.

In North Carolina, the Coastal Resources Commission is reviewing forecasts for sea-level rise compiled by its science panel. A 2014 Union of Concerned Scientists report already warns that minor tidal flooding will become a near-daily, “incessant” event in the Wilmington area by 2045. Once approved by the commission, the North Carolina General Assembly will vote on whether the science panel’s sea-level forecasts must be taken into account for future building projects.

Critics of climate change projections are concerned that building with sea-level rise in mind will drive up building costs, but senior White House officials insist that the stricter federal standards will only add between .25 percent and 1.25 percent to the cost of construction. The standards will save taxpayers money in the long run, because it could significantly reduce the federal government’s recovery costs, said White House officials.

Obama’s executive order is “a positive step to be more prepared for the threat that we’re already facing from rising sea levels and more intense storms. We have to start applying what the science is telling us, and what we’re seeing from recent events, to investment decisions and codes and standards — ideally at all levels of government,” said Georgetown Climate Center executive director Vicki Arroyo.