What is the 100-year floodplain?
The 100-year floodplain, or base floodplain is that area adjacent to rivers, streams and lakes that has been determined to have a 1% statistical chance of being flooded in any given year. The Federal Emergency Management Agency (FEMA) completes hydrologic and hydraulic studies of watercourses and water bodies to determine flood elevations relative to local topography. FEMA uses the term Flood Insurance Study (FIS) for these investigations. An individual FIS is completed for each municipality or county. The floodplain maps, called Flood Insurance Rate Maps (FIRMs) are the companion documents to the FIS.

Learn more about understanding floodplains.

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1. What is an easement?
2. What is a right-of-way?
3. My mortgage lender says I need flood insurance, how is this need determined?
4. What is the 100-year floodplain?