As Sea Levels Rise, Homes Continue to Sprout in U.S. Flood Zones

NEW YORK — New homes are going up fastest in high-flood risk areas in many U.S. coastal states, scientists said on Wednesday, despite increasing awareness that global warming has made living in such areas even more risky.

Science and communication non-profit Climate Central found that one-third of coastline states that will run a 10% risk of ocean inundation each year by 2050 saw new housing sprouting at rates higher than on safer ground.

“The attraction of living by the water is obvious,” said Ben Strauss, a climate scientist at Climate Central who led the research, told the Thomson Reuters Foundation.

In the northeastern state of Connecticut from 2010 to 2017, housing valued at $880 million went up more than three times faster in high-risk flood zones than on safer ground.

Another East Coast state, New Jersey, outpaced all other states at building homes in high-risk zones, with about 4,500 new homes worth $4.6 billion erected in such areas from 2010 to 2017, the researchers reported.

U.S. law does not bar building in areas predicted to flood every 100 years, as long as risk reduction regulations are adhered to, and owners purchase flood insurance.

Some 5% of the U.S. population lived in these areas in 2015, a 2017 report by New York University’s Furman Center found.

The researchers focused on areas at higher risk for flooding — defined as every 10 years by 2050 — to provide practical input for homeowners seeking mortgages, Strauss said.

“You can buy a property that has never or rarely flooded today, but by the end of the mortgage could be flooding every few years because of sea-level rise,” he noted.

Such intermittent floods can damage and devalue homes, degrade infrastructure, rust out cars and spawn mold, the report said.

Other states where new home construction in high-danger zones versus safer areas included Rhode Island, Delaware, Maine, Mississippi, New Hampshire and South Carolina.

The report obtained data on housing location and value from real estate database company Zillow.

The scientists drew their conclusions by combining flood and sea-level rise projections that followed a scenario where planet-warming greenhouse gas emissions are cut moderately, the report said.

Martin said the findings showed the need to boost incentives, such as existing government programs to buy out homeowners in flood-prone areas, to encourage people to live further from the coastline.