Rockingham County coastal flood maps become effective in January 2021

On July 29, 2020, the Federal Emergency Managemenr Agency (FEMA) issued the Letter of Final Determination (LFD) to finalize the preliminary Flood Insurance Rate Maps (FIRMs) for certain communities in Rockingham County. FEMA originally issued the preliminary maps in 2014 followed by revised preliminary map panels for several communities in 2016. The LFD establishes the effective date of the new FIRMs and Flood Insurance Study (FIS) report and provides communities six months to adopt them prior to the January 29, 2021 effective date.

The FIRMs are produced for communities that participate in FEMA’s National Flood Insurance Program. They are used by:

• Community officials to determine where and how their community floodplain ordinance applies for development.
• Lenders to determine if a building must have a flood insurance policy as a condition of a loan.
• Insurance agents to determine the cost of a flood insurance policy for a building.
• People interested in understanding what risks from flooding are in their area.

The new maps reflect an updated coastal flood hazard analysis. Light Detection and Ranging (LiDAR)-derived topographic data was used to delineate updated floodplains based on the results of the analysis. Zone A (approximate) floodplain boundaries were also updated based on limited engineering analyses and the same topographic data.

The preliminary maps can be viewed via FEMA’s Map Service Center or the NH Flood Hazards Viewer. The final maps (with no additional flood hazard changes) will be available through the same sources by the new effective date.

For more information about the project, visit the NH Office of Strategic Initiatives’ (OSI) Coastal Mapping Project webpage. OSI will be coordinating with affected communities in the coming months about the map adoption process and is planning related training about the new maps for the fall.