Methodology

To identify the cities that will soon be under water, 24/7 Wall St. reviewed data from “Underwater,” published June 2018 by Cambridge, Massachusetts-based environmental watchdog group the Union of Concerned Scientists. The study identified U.S. coastal communities where the largest number of residents live in properties that are projected to face by 2060 the highest level of chronic and disruptive flooding, or effective inundation — defined as being at risk of flooding 26 times or more per year. We reviewed the number of properties and total value of properties that are exposed to flood risk based on a “high” scenario calculated by the Union for Concerned Scientists, which entails a 6.6 foot rise in sea level by the end of the century. The places on our list, which are county subdivisions, are those in which the largest number of residents live in housing that would be exposed to the effective inundation.

Cities and institutions can mitigate flood damage by implementing wetlands, levees, and other mechanisms, and many of the cities on this list have taken steps to implement these measures. It is important to note that the estimates published by the UCS do not take into account the mitigating effects of such mechanisms.