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Defining Flood Risks

Defining Flood Risks

Flooding can happen anywhere, but certain areas are especially prone to serious flooding. To help communities understand their risk, flood maps (Flood Insurance Rate Maps, FIRMs) have been created to show the locations of high-risk, moderate-to-low risk and undetermined-risk areas. Here are the definitions for each:

High Risk Areas
In high-risk areas, there is at least a 1 in 4 chance of flooding during a 30-year mortgage. All home and business owners in these areas with mortgages from federally regulated or insured lenders are required to buy flood insurance. They are shown on the flood maps as zones labeled with the letters A or V.
Moderate to Low Risk Areas
In moderate-to-low risk areas, the risk of being flooded is reduced but not completely removed. These areas submit over 20% of NFIP claims and receive one-third of disaster assistance for flooding. Flood insurance isn't federally required in moderate-to-low areas, but it is recommended for all property owners and renters. They are shown on flood maps as zones labeled with the letters B, C or X (or a shaded X).
Undetermined Risk Areas
No flood-hazard analysis has been conducted in these areas, but a flood risk still exists. Flood insurance rates reflect the uncertainty of the flood risk. These areas are labeled with the letter D on the flood maps.

Understanding flood maps Understanding flood maps

FEMA conducts a Flood Insurance Study and uses this data to create the flood hazard maps.

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Undergoing a Map Change Undergoing a Map Change

Flood risk can and does change over time. FEMA frequently updates flood hazard maps.

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Levee Simulator Levee Simulator

The FloodSmart Levee Simulator shows different ways a levee can fail.

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PRIMARY RESIDENCE DISCLAIMER


For flood insurance rating purposes, a primary residence is a building that will be lived in by the insured or the insured's spouse for at least 80 percent of the 365 days following the policy effective date. If the building will be lived in for less than 80 percent of the policy year, it is considered to be a non-primary residence.

How Can I get Covered?

  • Rate your risk
  • Estimate your premiums
  • Find an agent
 

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Last Updated: Sunday, 13-Apr-2014, 4:35 PM (EDT)

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