High Tide Tax: The Price to Protect Coastal Communities from Rising Seas

Adapting to climate change in the U.S. will cost trillions of dollars. But to date, there has been little analysis of what the costs will be to individual states, counties, congressional districts, and cities across the country. This study provides conservative cost estimates for one small but essential piece of climate adaptation: building seawalls and other barriers to protect the coastal contiguous US from near-term sea-level rise. While these numbers represent just a slice of the total cost to protect communities from a much wider range of climate impacts, we present these planning-level estimates to identify high-risk communities with the greatest costs, to inform decisions over the next 5-10 years, and to provide a better idea of the scale of climate adaptation costs taxpayers are currently expected to cover on their own.