Coastal Flood Risk
Flood Insurance Studies produced by the Federal Emergency Management Agency (FEMA) per the National Flood Insurance Program regulations and guidelines adopt storm-induced erosion criteria often called the “540 rule”. The methods used in the erosion analysis have been in place since the 1980s. Since the rule’s application, additional data and recent evidence have become available leading FEMA to identify this approach as an area in need of updating. FEMA is exploring opportunities to improve FEMA guidelines for erosion criterion and revise NFIP regulations and guidance, to ensure that storm-related erosion hazards are appropriately evaluated and mapped along US coastlines.