When are ABFEs required?
Date Published: May 2014
CDBG-DR funds require the best available data +1 plus one foot for new construction and substantial improvement of structures. Substantial improvement is any repair, reconstruction, modernization, or improvement of a structure, the cost of which equals or exceeds 50 percent of the market value of the structure before the improvement or repair is started or if the structure has been damaged, and is being restored, before the damage occurred. Substantial improvement also includes improvements to a structure that increase the average peak number of employees or customers likely to be onsite at any one time or the number of residential units in the project more than twenty percent. The cost includes all non-federal and private funds in addition to the Federal assistance. The substantial improvement elevation requirements do not apply to structures listed on the National Register of Historical Places or on a State Inventory of Historic Places. The Advisory Base Flood Elevations (ABFEs) are the required data source until new FEMA data such as Preliminary and Final FIRMs are issued. One foot must also be added to the base flood elevation of both Preliminary and Final FIRMs when using CDBG-DR funds for new construction or substantial improvement in the Sandy recovery area.
Please note that if the state or local government requires a higher standard than best available data +1, then the higher state or local standard would apply. Contact the local building official to determine exactly what you are required to do to meet or exceed floodplain management and other reconstruction requirements.