About the Study

The Federal Emergency Management Agency (FEMA) Region III office has initiated a coastal analysis and mapping study to produce updated Digital Flood Insurance Rate Maps (DFIRMs) for coastal counties within Region III.  The new coastal flood hazard analyses, initiated in the Fall of 2009, will utilize updated 1% annual chance stillwater elevations obtained from a comprehensive storm surge study being concurrently performed by FEMA Region III.   

The storm surge study is one of the most extensive coastal storm surge analyses to date, encompassing coastal floodplains in three states and including the largest estuary in the U.S. Ultimately, the study will update the coastal storm surge elevations within the states of Virginia, Maryland, Delaware, and Pennsylvania including the Atlantic Ocean, Chesapeake Bay and its tributaries, and the Delaware Bay. This study differs from the storm surge mapping performed as part of Hurricane Evacuation Studies in that the resulting stillwater elevations are based on probability of occurrence as opposed to Hurricane Category events. Emergency Managers should still utilize their hurricane evacuation studies and hurricane category storm surge maps for evacuation planning and decision-making purposes.  

An updated coastal flood study is needed to obtain a better estimate of coastal flood hazards and risk for Region III.  The current, or effective, Flood Insurance Rate Maps (FIRMs) are outdated primarily due to the age of data and methodologies used in producing the effective FIRMs, which date back to the mid-to-late 1970s.  Major changes in National Flood Insurance Program (NFIP) policies and methodologies have occurred since the effective date of many FIS studies in the area, creating the need for an update that would reflect a more detailed and complete hazard determination. 

This web site will serve as the central repository for the coastal study and will include study updates, results, as well as the locations and dates of outreach activities.

Spatial Scope

FEMA Region III encompasses Delaware, the District of Columbia, Maryland, Pennsylvania, Virginia, and West Virginia.  Virginia has the largest number of coastal communities, with 28 counties along the Atlantic and Chesapeake Bay shorelines.  Maryland has a total of 16 counties on the Atlantic Ocean and Chesapeake Bay coast, and Delaware has 3 counties on the Atlantic Ocean and Delaware Bay coastlines.  Pennsylvania has 3 counties which are affected by storm surge propagating up the Delaware River.   

A strategy for prioritization of updating the FIRMs was essential given the large geographic extent and number of counties within FEMA Region III.  Restudy prioritization considered the following criteria: 1) population/development density, 2) repetitive losses, 3) changes in stillwater elevations, and 4) ongoing efforts to update existing Flood Insurance Studies.