Sea levels are rising and the southeast has already lost billions in property value, a recent study shows.

Scientists have found $7.4 billion was lost in home values across North Carolina, South Carolina, Virginia, Georgia and Florida because of sea level rise flooding from 2005 to 2017.

Scientists at First Street Foundation — a technology nonprofit dedicated to increasing awareness of sea level rise — used data from the National Oceanic and Atmospheric Administration, U.S. Geological Survey, local governments, the National Weather Service and the U.S. Army Corps of Engineers to estimate flood risks.

Scientists used data from local governments to determine changes to property values over time.

FSF used the data to create an interactive tool — Flood iQ — that allows people to search communities and individual properties to see how much value they’ve lost, and could lose in the future due to sea level rise.

“Sea level rise is something that is already costing the American public billions of dollars and in the last five years alone has sped up 66 percent,” Matthew Eby, FSF executive director, told The News & Observer.

Steven A. McAlpine, head of data science at FSF, and. Jeremy R. Porter, a Columbia University lecturer and FSF statistical consultant, recently released an academic paper in the journal “Population Research and Policy Review” showing $465 million was lost in Miami-Dade County real-estate market value from 2005 to 2016 due to sea level rise flooding.

That peer-reviewed analysis was expanded to cover all of Florida, South Carolina, North Carolina,Virginia and Georgia by analyzing more than 5.5 million real estate transactions in those states and extrapolating the results to 12.2 million properties, to find a total home value loss of $7.4 billion since 2005.

Property value loss by state

▪ Florida: -$5.42 billion

▪ South Carolina: -$1.11 billion

▪ North Carolina: -$582 million

▪ Virginia: -$280 million

▪ Georgia: -$15 million

Number of properties that lost value by state

Across all five states, 616,626 properties have lost value, the data shows.

▪ Florida: 384,548

▪ South Carolina: 92,775

▪ North Carolina: 81,908

▪ Virginia: 47,035

▪ Georgia: 11,360

The study is the first of its kind to show depreciation of home values has already taken place in the United States, Eby said. Previous studies have forecast the negative effects sea level rise could have, but haven’t shown what it has already cost people. It’s also the first academic paper to demonstrate that sea level rise is directly to blame for a decrease in coastal home values and how local flooding plays a role in that reduction, Eby said.

“It is one thing to project what the future impacts of sea level rise could be, but it is quite another to know that the market has already responded negatively to this threat,” McAlpine said.

“We need to act now,” Porter added. “The ability to pay for solutions to sea level rise is directly related to our ability to finance them. We do not want to see the beginning of a domino effect, where lost property value lowers the tax base and cripples our ability to finance solutions.”

The study also accounted for value loss during the recession and other market trends, McAlpine said.

“By analyzing all properties transactions that occurred between 2005 and 2016, we were able to quantify the impact of the recession separately from the additional impact of tidal flooding,” he said. “We could isolate the net impact of tidal flooding risk on affected properties because we quantified the impact the recession had on all properties.”

Flood iQ

The team behind Flood iQ used data on tidal flooding, hurricane storm surge, projected sea level rise and more to determine what properties are at risk and which have already seen devaluation. It also projects how much value properties could continue to lose based on current projections of sea level rise through 2033.

The interactive tool allows users to search cities down to individual properties to determine:

▪ Whether that property or area is at risk;

▪ What types of risks it faces;

▪ Projected sea level rise for that area;

▪ How property values have been affected;

▪ How much the communities could stand to lose in the future;

▪ How many properties — residential and commercial — are at risk;

▪ Emergency and other facilities such as schools threatened by flooding;

▪ What public officials they can contact about flood abatement and property protection.

In North Carolina, for example, Topsail Beach is expected to see sea levels increase by about 6.36 inches on average in the next 15 years.

Topsail Beach has already seen a loss of more than $4.2 million in property value since 2005, the data shows, and is set to lose another $4.85 million by 2033 if no action is taken — not including any additional properties built between now and then.

About 356 homes are at high risk of flooding in Topsail Beach today. That number is expected to nearly double in 15 years without action.

In Wilmington, the sea level is expected to rise by about the same as in Topsail Beach. But Wilmington has already lost more in property value and stands to lose more in the future — $6.3 million since 2005, another $7.3 million in the next 15 years.

Four schools in Wilmington already are at high risk of flooding, and 7 could be at risk by 2033, along with at least one medical facility.

Perhaps the area most at risk in the Carolinas is Charleston, South Carolina, where more than $266.2 million in property values has already been lost since 2008.

Charleston could see another $387.3 million lost — a total of more than $653.5 million in lost property value by 2033. Of the five states analyzed in the study, Charleston was the No. 3 city for most property value lost. Miami Beach and Hollywood, Florida were the only two that have lost more.

Today, 5,543 homes are at high risk in Charleston. In 15 years, 8,349 will be at high risk.

By 2033, 2 police stations, 52 religious buildings, 17 schools, 6 medical facilities and 3 fire stations will be at high risk of flooding.

Myrtle Beach, which has already lost more than $373,917 in property value since 2008 could lose an additional $560,875 — nearly $1 million total by 2033.

Hilton Head Island has already lost nearly $49 million since 2008. In 15 years, it could see that total rise to more than $121.6 million, with more than 2,600 homes at high risk.

The basic projections do not include any rain or weather that could worsen sea level rise flooding.

The Flood iQ map, however, shows the areas at risk and the depth of flooding expected from: normal tidal flooding as sea levels increase, peak tidal floods, and hurricanes (categories 1, 3 and 5).

“Flooding does not have to be a way of life for coastal communities. Cities can take measures to mitigate the impact and protect property values,” Eby said. “But without action, the rate of home value loss will only accelerate.”

Forbidden sea level rise report

Sea-level rise scenarios have prompted opposition from some economic development interests on North Carolina’s coast that alleged long-range forecasts could be wrong.

When a state science panel reported in 2010 that seas on the coastline could rise by as much as 39 inches over the next century, North Carolina state legislators passed a law forbidding communities from using the report to make new rules.

A new report in 2015 looked only 30 years to the future and forecast a rise of 2 to 10 inches, depending on location.

To search cities, towns and properties, go to floodiq.com. The tool is also available en Español.