Congressional Report on US Islands Coastal Shoreline Erosion

In December 2020, the US Congress directed the FHWA to conduct an investigation and produce a report on coastal shoreline erosion and future sea level rise upon roadways on the six US Islands/Island chains (US Islands) of America Samoa, Guam, Hawai’i, Northern Mariana Islands, Puerto Rico and US Virgin Islands. South Coast Engineers developed that report during the global pandemic by gathering relevant literature data and resources; investigating the scientific and engineering background; developing vulnerability assessment approaches considering resilience; and some limited site visits for each of these islands. This report estimates roadway mileages affected under different flooding and climate change (sea level rise) scenarios and describes opportunities for technical assistance and future studies.