coastal flood zones

Graphic from the MA DEP brochure Protecting Coastal Property from Major Storm Damage

Background information about FEMA, Flood Insurance Rate Maps, and the Buzzards Bay CCMP

The Planning for a Shifting Shoreline Action Plan in the Buzzards Bay Comprehensive Conservation and Management Plan focuses on planning for storm damage and rising sea levels along the coast to protect living resource and water quality. The Goals of this action plan are:

  • Protect public health and safety from problems associated with higher waters and shifting shorelines.
  • Reduce the public financial burden caused by the destruction of or damage to coastal property.
  • Plan for the loss of buffering wetlands and shifting sand formations.

A key element for implementing this action plan is a good understanding the location of the 100-year floodplain (Federal Emergency Management Agency, or FEMA maps), barrier beaches, and areas of high erosion. This page provides maps and key links to this information. Property owners and engineers should consult original source FEMA National Flood Insurance Rate Maps (FIRMs) to definitively identify flood plain boundaries. The maps and links below provide good estimates of those boundaries. More information about the FIRMs can be found on the FEMA National Flood Insurance Program page.


FEMA has provided a FIRM MAP display page. At this page you can print a personalized "FIRMETTE" map for your home. Go to this FEMA page for flood zone definitions. Because of the approximate nature of even the original FIRMs, property owners sometimes conduct their own studies to identify flood plain elevations. (Visit FEMA page: How To Request a Flood Hazard Determination Review from FEMA. On this and other pages on this site we provide some useful tools to help interested parties identify floodplains.

Updated FEMA FIRM maps for Buzzards Bay Communities

In 2009, FEMA updated its FIRM maps for Bristol County. Draft hard copy maps for Barnstable and Plymouth County have been released to municipalities, but have not been finalized. To check the status of this effort, go to this FEMA Multi-Year Flood Hazard Identification Plan (MHIP) site and this flood hazard mapping information page. To download maps or digital GIS data, visit the FEMA Map Service Center (choose "flood maps" for pdf maps or "DFIRM databases" for GIS files). Here is a Fairhaven, MA FIRM map, illustrating their new format.

Old versus new FEMA lines

These two images show revisions in FEMA flood zones (red= velocity zone, blue = 100-year flood plain) at a site along Nasketucket Bay in Fairhaven.

Hurricane Surge Inundation Maps

The US Army Corps of Engineers, as part of its Hurricane Evacuation Studies for Massachusetts, produced Hurricane Surge Inundation Maps for New England, also known as "SLOSH" maps. Hurricane surge elevations were determined by the National Hurricane Center using the SLOSH model (Sea, Lake and Overland Surge from Hurricanes), and assume peak hurricane surge arrives at either mean tide or mean high tide, as indicated at the bottom of the maps. The hurricane surge inundation areas shown on the maps depict the inundation that can be expected to result from a worst-case combination of hurricane landfall location, forward speed, and direction for each hurricane category. Ground elevation data was obtained from the USGS National Elevation Data Set. GIS Data for these maps can be obtained at this site. An explanation of the SLOSH map methodology and technical findings is contained in this ACOE 1997 SE MA hurricane Inundation technical report. FEMA put together this training package to explain how SLOSH data can be used.