This analysis estimates the number of homes and commercial properties throughout the coastal United States that will be put at risk from chronic, disruptive flooding—defined as flooding that occurs 26 times per year or more—in the coming decades. It brings together data on coastal regions that are projected to experience this type of flooding, and data on existing properties provided by Zillow, the online real estate company.
The findings indicate that sea level rise, driven primarily by climate change and even absent heavy rains or storms, puts more than 300,000 of today’s homes and commercial properties in the contiguous United States at risk of chronic, disruptive flooding within the next 30 years. The cumulative current value of the properties that will be at risk by 2045 is roughly $136 billion.
In those 30 years—encompassing the terms of a typical mortgage taken out today—what will the properties be worth if they are flooding on a chronic basis? And how will the broader coastal real estate market fare in the long term? The analysis finds that by the end of the 21st century nearly 2.5 million residential and commercial properties, collectively valued at $1.07 trillion today, will be at risk of chronic flooding. Many experts in risk assessment, credit ratings, real estate markets, insurance markets, and flood policy (dozens of whom were consulted for this report), recognize that the risk of sea level rise to coastal real estate is significant and growing—and that for the most part, financial markets do not currently account for these risks.