Where are floodways shown on the FIRM in relation to a levee?

Floodways are the channels of rivers and streams that carry floodwaters and the adjacent land areas that must remain free of encroachments to allow for floodwaters to flow without causing increased flooding elsewhere. When it comes to levees, floodways are typically shown on Flood Insurance Rate Maps (FIRMs) on the landside toe of the levee.

The landside toe is the part of the levee that faces away from the floodwater source. It is crucial to delineate floodways accurately because any encroachment on this area could potentially increase flood risks by reducing the capacity of the floodway. Therefore, identifying the floodway as being on the landside toe is essential for effective floodplain management and ensuring proper safety measures are in place for communities behind levees. This relationship is vital for both mapping and regulatory purposes within the National Flood Insurance Program (NFIP).