Shoreline change, seawalls, and coastal property values

Abstract

We investigate the effects of shoreline change and protective structures (seawalls) on home values, using data on residences sold between 2000 and 2010 in the coastal towns of Marshfield, Duxbury, and Plymouth, Massachusetts. These towns comprise shorelines that exhibit moderate rates of shoreline change, relative to other shorelines in the state, with extensive armoring. We investigate explicitly the effects of hard structural protection in combination with environmental amenities and hazards (distance to a beach, elevation of a property, location in a flood zone). We find that homeowners pay a premium in housing markets for nearshore properties protected by nature (higher elevations or more stable shorelines) or by humans (seawalls). The average marginal increase in nearshore property values associated with a 1m rise in elevation is 2 percent, a 1m (horizontal distance) decrease in the erosion rate is 0.2 percent, and location behind a seawall is 10 percent. The effects of erosion, elevation, and seawalls appear to be limited to properties located in close proximity to water or to oceanfront residences. Overall, the benefits of access to ocean amenities dominate the risks of exposures to hazards associated with shoreline change.