What are ABFEs and the best available data +1 standard?
Date Published: May 2014
The Base Flood Elevation refers to the level of the flood that has a one percent chance of being equaled or exceeded in any given year. Advisory Base Flood Elevations (ABFEs) are maps that provide a better picture of current flood risk than the existing Flood Insurance Rate Maps (FIRMs), which in some cases are more than 25 years old. The new ABFEs are the recommended elevation of the lowest floor of a building. The ABFEs are based on FEMA coastal studies that were completed before Hurricane Sandy. The studies include data that has been collected and analyzed over a number of years. Though advisory now, eventually information used to develop the ABFEs will be incorporated into official FIRMs. The ABFEs are the required data source until new FEMA data such as Preliminary and Final FIRMs are issued. More information on ABFEs can be found on FEMA’s Region 2 website.
HUD and other Federal agencies are requiring an additional foot of elevation for projects in the Sandy recovery area. The additional foot is a safety precaution in anticipation of sea level rise and climate-related impacts. CDBG-DR funds require elevation of the lowest floor to one foot above the Base Flood Elevation shown in the best available data for new construction and substantial improvement of structures. Please note the following when applying the best available data plus one foot standard.