Hidden costs to building foundations due to sea level rise in a changing climate.

Coastal civil infrastructure is vulnerable to the effects of climate change. Hurricane storm surge and coastal flooding can cause significant hydrostatic and hydrodynamic loads on structures while saltwater intrusion (SWI) may lead to deterioration of foundations. The effects of saltwater intrusion due to Sea Level Rise (SLR) on the foundations of buildings and other civil infrastructure is poorly understood. Such damages may not be detected in a timely fashion nor be insured, leading to significant and unanticipated expenses for building owners. In this study, we evaluate the impact of SWI due to various SLR scenarios on the corrosion of reinforcement in foundations of nearly 137,000 residential buildings in low-lying areas surrounding Mobile Bay, AL. We find that the potential for costly damage is significant. Under an extreme SLR scenario, the annual expected repair costs for the foundations of the studied homes may reach as much as US$90 million by 2100.