Sea-level rise, caused by climate change, is on a crisis course for many U.S. coastal communities. New research finds that as many as 311,000 homes on the East Coast and Gulf face being frequently flooded within the next 30 years.

According to a new study by the Union of Concerned Scientists, rising oceans will jeopardize coastal residences collectively worth $120 billion by 2045 if greenhouse gas emissions are not severely curtailed. UCS says that — within two decades — this is likely to inflict a huge financial and experiential cost on about half a million Americans who live in the areas at greatest risk.

Putting a dollar value on these concerns is deeply disturbing. A 2017 article in “Think Progress” reports: 

“[Accelerating sea-level rise] is very bad news for U.S. coastlines, and the only question left for Americans is: When will coastal property values crash? … Values will start dropping before we hit a few feet of sea-level rise. They will crash when a large fraction of the financial community — mortgage bankers and opinion-makers, along with a smaller but substantial fraction of the public — realize that it’s too late for us to stop catastrophic sea-level rise.”

Sean Becketti, economist for mortgage giant Freddie Mac, warns: “The country is facing a trillion-dollar bubble in coastal property values, a time-bomb which has been inflated by U.S. taxpayers in the form of the National Flood Insurance Program.” 

Coastal officials need to conduct a rigorous “reality-check” before making matters worse by approving still more reckless development. 

Kyler is director of Center for a  Sustainable Coast