North Carolina among leaders in new homes where sea level rise could increase flood risk
RALEIGH - North Carolina was among the nation’s leaders between 2010 and 2016 in building homes that will be in the 10-year floodplain if a moderate sea level rise projection holds true, according to a new study conducted by Climate Central and Zillow.
The two organizations used an open-source building footprint database and sea level rise models based on different emissions scenarios to determine which new homes will be at risk of flooding in the future.
In North Carolina, researchers found, more than 1,900 homes worth $840 million have been built in areas that are likely to be in a 10-year flood zone in 2050 if global emissions are cut roughly in line with the guidelines set out in the Paris Accords. Two Outer Banks counties are among the nation’s top 10 for at-risk homes, according to the study, called Ocean at the Door. Dare County has built 502 homes worth $216 million and Currituck has built 375, worth $135 million, the report says.
Peter Girard, a Climate Central spokesman, said, “I don’t think there will ever be a time when people aren’t interested in living close to the beach or close by the rivers. But at least in the data like we put out there, you can sort of identify the risk, quantify the risk to your family, to your home, to your property values, and that’s really important.”
Climate Central is a nonprofit focused on describing facts about climate change and its potential impact, while Zillow is an online real estate and rental marketplace providing data such as home value estimates.
Due to its nonprofit status, Climate Central does not comment on specific policy proposals, rather emphasizing the importance of homeowners knowing their risk. As sea levels rise, the report states, floodwaters will reach further inland than they do now, damaging homes and infrastructure.
“As we think about flooding in the coming years and how we continue to develop homes in those areas, it’s really important for homeowners and buyers to keep this in mind when they’re making decisions,” said Sarah Mikhitarian, a Zillow senior economist who worked on the project.
New Jersey led the country in increased building in risk zones, with 4,524 homes totaling $4.61 billion in value. That total, the report stated, is likely attributable to rebuilding after 2012’s Superstorm Sandy.
Other North Carolina counties the study found to have built in future risk areas were Carteret, with 216 homes in a 10-year flood zone under the moderate sea level rise scenario; Brunswick, with 204; and Onslow, with 128.
North Carolina has also seen storms in recent years, with record flooding inundating much of Eastern North Carolina in 2016 and again during Hurricane Florence last fall.
Flooding after Florence set new records at 28 stream gages, according to a U.S. Geological Survey study, often breaking records set by Matthew. And scientists at the First Street Foundation used data from several federal and local sources to determine 11,000 fewer homes in the Carolinas and Virgina would have been affected by storm surge if the ocean had been at 1970 levels, with NOAA gauges indicating an average sea level rise of about 6 inches in the Carolinas since 1970.
Dare County, identified by Climate Central and Zillow as one of the nation’s leaders in building in future risk zones, leads the state in National Flood Insurance Program (NFIP) policies, with 12,875 properties defined as having a 1% chance of flooding in a given year.
Donna Creef, Dare County’s planning director and floodplain administrator, said she expects residents to continue to flock to the Outer Banks, but said she and other county administrators are concerned about flood risks. Dare has participated in the NFIP since 1978, with policy holders receiving a 15 percent discount due to elevation standards and risk outreach programs.
“I tell people that Dare County’s been practicing resiliency for years,” Creef said, “because we’ve been elevating our structures for years, and we participate in the (Coastal Area Management Act) program. We recognize that conditions are different than they were 30 or 50 years ago, whether you call it sea level rise or climate change.”
Dare is in the midst of its flood map reauthorization process, in which the Federal Emergency Management Agency and state officials use updated models to determine who needs to purchase flood insurance in order to obtain a mortgage. In Dare County, officials have told Creef the number of properties in the annual floodplain will decrease from 12,875 to 8,493.
Creef and other county officials are concerned enough about the change they are working on a local regulation to be enacted in conjunction with the new flood maps. The local regulation would require elevating homes whose natural elevation is not to a level based on previous flood maps
Dare is also enacting an awareness campaign to let people know the benefits of purchasing flood insurance, particularly if they are in areas FEMA recognizes as having relatively low risk.
“The other concern we have is, people are going to realize they’re in (the 500-year flood plain) and say, ‘I don’t need flood insurance anymore, I must not be at risk to flood.’ We know that’s a fallacy. ... Just because the flood maps say you’re not going to flood doesn’t mean you won’t,” Creef said.
This story was produced with financial support from Report for America/GroundTruth Project, the North Carolina Community Foundation and the North Carolina Local News Lab Fund. The N&O maintains full editorial control.