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Current NH Floodplain Mapping Activities

Information about FEMA's floodplain mapping activities currently underway in New Hampshire.

FEMA Risk MAP Program

FEMA’s current flood mapping program is called Risk MAP (Mapping, Assessment and Planning). The goal of the Risk MAP program is to deliver quality flood hazard data and maps that increase public awareness about flooding and lead to action that reduces risk to life and property. To learn more about Risk MAP in New Hampshire, view the 2015 New Hampshire Risk MAP Business Plan.  pdf file

The Risk MAP Discovery Process

The first step in a Risk MAP flood mapping project is called the Discovery process. Discovery is used to help determine whether a mapping project is actually needed, and if so, what the scope of the project will be. Several Discovery projects have recently been completed and the mapping projects listed in the section below are now underway in the state.

Risk MAP Flood Mapping Projects in New Hampshire

FEMA Risk MAP projects currently underway that affect communities in New Hampshire are listed below. Schedule information listed is provided courtesy of FEMA and is subject to change.

  • Contoocook/Pemigewasset Watersheds - FEMA has finalized scopes of work for new mapping projects based on the results of a Discovery project to determine flood map update needs in the watersheds. Communities will receive copies of Discovery Reports in late 2019. Field surveys and updated flood analyses are currently being performed.
  • Coos County Mapping Project - Zone A floodplain boundaries are being updated and Zone AE boundaries redrawn based on more recent/detailed topographic data. These updates will be incorporated into the flood maps at a later date.
  • Merrimack River Watershed  pdf file - The development of revised flood maps based on updated engineering analyses and topographic information is currently underway. Meetings were held to review work maps showing flood hazard changes with community officials in July 2019. Issuance of preliminary flood maps is anticipated in 2020.
  • Middle Connecticut Watershed pdf file – Field surveys to support updated flood hazard analyses are currently being performed. Updated flood maps will be prepared following completion of the surveys and the new analyses.
  • Nashua River Watershed pdf file - Updated flood analyses are complete and revised floodplain mapping is underway. It is anticipated that meetings with community officials to review draft work maps will occur in late 2019 or in 2020.
  • Millers Watershed pdf file - Field surveys to support updated flood hazard analyses are currently being performed. Updated flood maps will be prepared following completion of the surveys and the new analyses.
  • Rockingham County Coastal Study - FEMA is moving forward with finalizing preliminary flood maps issued in 2014 and 2016. It is anticipated that a Letter of Final Determination (LFD) will be issued to communities in 2020. The maps will become effective 6 months after the LFD issuance.
  • Salmon Falls—Piscataqua Rivers Watershed (Inland) - Preliminary flood maps showing revised flood hazard information will be distributed following the LFD issuance for the coastal project above since some map panels are affected by both projects.
  • Waits/Pemigewasset Watersheds - Zone A floodplain boundaries have been updated using more recent/detailed topographic data and new engineering analyses. These updates will be incorporated into the flood maps at a later date.
  • Winnipesaukee River Watershed pdf file - Updated flood analyses are currently being performed which, along with new topographic data, will be used to create digital flood maps.

You can view the location of each of these projects on our interactive map.

To find out more about any of these projects, contact Samara Ebinger of OSI at samara.ebinger@osi.nh.gov.

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NH Office of Strategic Initiatives
Governor Hugh J. Gallen State Office Park
Johnson Hall, 3rd Floor  |  107 Pleasant Street  |  Concord, NH 03301
(603) 271-2155  |  fax: (603) 271-2615