What is base flood elevation?

Base flood elevation (BFE) is a value determined by the Federal Emergency Management Agency (FEMA) that helps identify the flood risk in a certain area. By extension, it also determines the risk a particular structure has of flooding if the water level rises. The BFE is the expected water level rise during a flood with a 1% chance of occurring in any given year.

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What are FEMA flood zones and base flood elevation?

FEMA uses the base flood elevation to classify areas at higher risk of flooding. The agency draws color-coded base flood elevation maps that indicate whether a site is above the "500-year" floodplain — an area that statistically has a yearly chance of flooding of 0.2% — and the "100-year" floodplain which corresponds to the flooded area of the BFE.

Areas in the 100-year floodplain are considered Special Flood Hazard Areas (SFHA) because of their significant risk of flooding. These zones all have codes beginning with either "A" or "V" such as "zone A99."

Can I find the base flood elevation number for my home's location?

If you're concerned about flooding or live in an area where flooding can occur easily — such as low elevation areas or places near major bodies of water —consult a FEMA flood map. If your home is in a zone coded A or V, there is an especially high risk of severe flooding. Underneath the zone's code will be an indication of the base flood elevation written as "EL," followed by a number indicating the number of feet that water would rise during a 100-year flood.

Based on that base flood elevation number, you can determine whether your home sits above or below the flood line for the 100-year flood. Depending on the SFHA code, you may be required to have an elevation certificate for your property showing the height of your property's lowest floor in relation to the benchmark BFE.

Flood insurance and base flood elevation

Properties in zones designated "A" or "V" are required to carry flood insurance if their mortgage comes from a government-backed lender. Additionally, all properties in zones with a "V" designation and properties in most zones with an "A" designation must have an elevation certificate. Learn more about how flood insurance works.