What Wall Does America Need, Why, and Where?: The Economics of Coastal Defense

The specter of overpowering hurricanes, sea level rise, and coastal flooding is raising a great deal of fear along America’s coastlines. But what is the appropriate public policy response? This paper uses a simple economic model to determine what coastal protection makes sense given current threats. The empirical analysis reveals that a large fraction of America’s coastline is in need of formal protection because of existing storm risk. Although sea level rise and future changes in storm intensity justify increasing levels of future protection, they have only a modest effect on current incentives to protect.