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Provides links and information regarding updates to the flood maps in the Piscataqua-Salmon Falls Watershed.

In 2016, updates to the Federal Emergency Management Agency (FEMA) flood maps for communities in the Piscataqua-Salmon Falls Watershed were identified as part of a Risk MAP Discovery Project.  FEMA, in partnership with the University of New Hampshire (UNH) – Earth Systems Research Center, AECOM, and the New Hampshire Office of Strategic Initiatives (OSI), is now working on a project to incorporate these changes.

Once the project is complete, updated flood maps that more accurately show the risk from flooding in the area will be available. The final maps will be used by communities who participate in the National Flood Insurance Program to manage development in high risk floodplain areas. The maps will also be used to determine where flood insurance is required and the rates that apply.

Project Area
This project affects all or portions of 26 inland communities within the Piscataqua-Salmon Falls Watershed in Rockingham and Strafford Counties as shown in green on the project area map

What Will Be Changing on the Flood Maps?
  • Portions of the Cocheco River and Exeter River, the Lamprey River within Rockingham County, and all of Dudley Brook will have revised engineering analyses performed. Updated flood boundaries and elevations will be mapped using the results of the analyses and new, more detailed topographic data.
  • Zone A approximate floodplains (i.e., floodplains with no flood elevation shown) will be remapped using limited engineering analyses and new, more detailed topographic data. In some areas, new Zone A floodplains may be added where there is a risk from flooding not currently shown on the flood maps.
  • All or portions of the following will have floodplains redelineated using new, more detailed topographic data in conjunction with the effective modeling data.
    • Bow Lake
    • Branch River
    • Club Pond
    • Cocheco River
    • Dames Brook
    • Ela River
    • Exeter River
    • Kicking Horse Brook
    • Mad River
    • Miller Brook
    • Salmon Falls River
Work Map Meetings
In August 2018, FEMA and UNH hosted meetings with community officials in the project area to review work maps showing the revised flood hazard information.

What Happens Next?
Release of Preliminary Flood Maps
The project team will prepare and release preliminary flood maps, which will be made available through FEMA’s Map Service Center website.

Consultation Coordination Officer (CCO) Meetings
A second round of meetings with community officials called CCO meetings will be held to review the preliminary flood maps.

Finalization of the Flood Maps
FEMA will hold a 90-day appeal period, during which anyone can provide scientific or technical information or other comments if they believe the preliminary maps should be revised. After any appeals are resolved, FEMA will finalize the maps. A Letter of Final Determination sent to community officials starts a 6-month period during which communities must adopt the new maps. At the end of this period, the final maps, available through FEMA’s Map Service Center, will serve as the basis for flood insurance rates and purchase requirements and local building regulations.

Learn More
For questions about this project, contact OPD's Floodplain Management Staff. For more information about FEMA's flood map update process, visit FEMA’s Risk MAP Lifecycle page.