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Current NH Floodplain Mapping Activities

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

What is the Risk MAP Process?

FEMA and its partners are currently working to update Flood Insurance Rate Maps (FIRMs), or flood maps across New Hampshire through their process called Risk MAP (Mapping, Assessment and Planning.)  This multi-step process takes several years to complete and can be simplified into four phases. Throughout this process, FEMA collaborates with community officials and residents, notifying communities of each step.
  • Phase 1: Discovery Phase. The discovery phase is used to help determine whether a mapping project is needed, and if so, what the scope of the project will be. For a list of all Discovery projects, including access to reports and meetings presentations, visit the FEMA Discovery Projects in New Hampshire webpage.
  • Phase 2: Analysis & Mapping. The analysis and mapping phase is when FEMA and its partners will conduct the engineering analyses that leads to the initial creation of draft works maps.
  • Phase 3: Preliminary Flood Map Release. The preliminary flood map release phase is when communities will receive preliminary flood maps and supporting preliminary flood hazard data for review and comment.
  • Phase 4: Map Adoption. The map adoption phase marks the end of the Risk MAP process and is when each community adopts the new maps into their floodplain regulations and the flood maps become final.
Learn more about the Risk MAP Process:

Current Mapping Projects

FEMA Risk MAP projects are currently underway across New Hampshire.  The information below is provided courtesy of FEMA and is subject to change.

Project Tracker: View our Status Tracker of Flood Mapping Projects in New Hampshire.
 
  • Contoocook River Watershed - FEMA has completed a Discovery project  to determine flood map update needs in the watershed.
    • Preliminary maps are available on the FEMA Flood Map Changes Viewer for Hillsborough, Merrimack and Sullivan Counties.
    • A Consultation Coordination Officer (CCO) meeting was held on July 26, 2023 for Merrimack County. View the slides.
    • A Consultation Coordination Officer (CCO) meeting was held on July 27, 2023 for Hillsborough County. View the slides.
  • Pemigewasset River Watershed - FEMA has completed a Discovery project  to determine flood map update needs in the watershed.
    • Preliminary maps are available on the FEMA Flood Map Changes Viewer for Grafton County.
    • Letters of Final Determination (LFDs) were issued for communities in Grafton County on August 8, 2023. NH Floodplain Management Program Staff will be in contact with communities to provide guidance on adopting the new maps.
  • Merrimack River Watershed - FEMA has completed a Discovery project  to determine flood map update needs in the watersheds.
    • Preliminary maps are available on the FEMA Flood Map Changes Viewer  for Merrimack, Hillsborough, and Rockingham Counties.
    • A Consultation Coordination Officer (CCO) meeting was held by FEMA on December 13, 2022 for Merrimack and Hillsborough Counties. View the webinar recording and the presentation slides.
    • A Consultation Coordination Officer (CCO) meeting was held by FEMA on June 13, 2023 for Rockingham County. View the webinar recording  and the presentation slides.
    • A 90-day appeal period is being held for a portion of Merrimack County, ending January 23, 2024.
    • A 90-day appeal period is being held for a portion of Rockingham County, ending March 18, 2024.
  • Middle Connecticut Watershed – Updated flood hazard analyses are currently being performed based on recently completed field surveys . Updated flood maps will be prepared following completion of the surveys and the new analyses.
  • Nashua River Watershed - FEMA has completed a Discovery project  to determine flood map update needs in the watersheds.
  • Millers Watershed - Updated flood hazard analyses are currently being performed. Updated flood maps will be prepared based on the analyses following completion. FEMA held a Flood Risk Review Meeting (Work Map Meeting) on February 15, 2023 to review and provide early feedback on the draft versions of the preliminary FIRM and FIS report and flood risk products.
  • Rockingham County Coastal Study - FEMA issued a Letter of Final Determination for this project on July 29, 2020. The new maps are effective January 29, 2021.
  • Saco River Watershed - FEMA has completed a Discovery project  to determine flood map update needs in the watersheds. The Discovery Report was released in December 2022
  • Salmon Falls—Piscataqua Rivers Watershed (Inland) - Preliminary flood maps showing revised flood hazard information are currently under development. This project is currently on hold pending funding.
  • Town of Farmington Levee Mapping Project - A web-based meeting with community officials was held March 31, 2020 to kick off this Levee Analysis and Mapping Project. Initial re-mapping options of the project area were shared with community officials in 2020.
  • Town of Lincoln Levee Mapping Project - A revised preliminary map will be prepared and issued following completion of levee reconstruction and levee accreditation.
  • Upper Androscoggin River-Headwaters Connecticut River Watershed - FEMA has initiated a Discovery project to determine whether a flood map update project is needed for the area, and if so, what the scope of the project will be. A virtual Discovery Meeting was held November 17, 2020 to provide community officials with information about the project.
  • Waits River-Connecticut River Watershed - FEMA has completed a Discovery project  to determine flood map update needs in the watersheds. The Discovery Report was released in October 2022.
  • Ammonoosuc River-Connecticut River Watershed - FEMA has completed a Discovery project  to determine flood map update needs in the watersheds. The Discovery Report was released in October 2022.
  • Winnipesaukee River Watershed - Updated flood analyses are currently being performed which, along with new topographic data, will be used to create digital flood maps.

Viewing Preliminary Maps and Data

Preliminary maps and data are available for viewing and downloading from the following websites:
  • FEMA Map Service Center - The official public source for flood hazard information produced in support of the National Flood Insurance Program (NFIP). Use the “Search All Products” to view and download preliminary flood hazard mapping products.
  • FEMA Preliminary Download Portal – This tool makes nation-wide preliminary data available in a centralized and easily accessible location, along with FEMA‘s other flood hazard mapping products.
  • FEMA Flood Hazard Changer Viewer – This viewer provides a single location to access flood hazard data across several data life stages and facilitates a better understanding  

Outreach Toolkit for Communities

Download the Outreach Toolkit: Preliminary Maps (.zip file) – for communities that have preliminary FIRMs available. 
 
Download the Outreach Toolkit: Pending Maps (.zip file) – for communities that have pending FIRMs available and have received an effective date through FEMA’s Letter of Final Determination (LFD).
 
  • Community website content
  • Social media posts
  • Sample press release
  • Letter/email template for properties in the SFHA
  • PowerPoint slide deck template
  • Postcard/Bill Insert
  • Talking points for community officials
Fact Sheets, Websites, & Other Online Resources: