FEMA Flood Hazard Map Updates

Currently in Vermont a flood map update process is underway in Bennington County and the Town of Richmond.   Beyond those areas there is no other work scheduled by FEMA.

At this time roughly half the state does not have access to Digital Flood Insurance Rate Maps (DFIRMs) this includes most of Addison, Grand Isle, Franklin, Lamoille, Orleans, Essex, Caledonia and Orange Counties.  Most of these maps are over 30 years old.

Years since Publication of Flood Maps

FEMA began a modernization process for the flood hazard maps in 2004 with the primary intention of making an official computer version available for users.  It was projected at that time that the process would be complete nationally by 2009.  Since that time pressure for updated studies (not just digitized), and the requirements, for those studies have increased the quality of the new maps at the expense of the quantity.

Since FFY11 the federal budget for map updates has been cut by 60% and priority for the dwindling investment has been directed to mapping flood hazards for coastal communities and communities behind levees.

Federal Budget Allocated to Update Flood Maps

When funding does become available for mapping in Vermont it will be through the process and standards of RiskMAP.   Through RiskMAP new flood hazard maps need to have high quality topography (i.e. the equivalent of two foot contour intervals) and a model-based delineation of flood hazards.  The map work will focus on watersheds (HUC-8).

HUC-8 Watersheds in Vermont

At this time multiple agencies have worked through USGS in Vermont to secure high quality topography from LiDAR for several watersheds that need updated flood hazard maps.  These areas include: the Missisquoi, Upper Connecticut River, and lower Otter Creek Watersheds.  LiDAR is also being acquired for much of the Lake Champlain Shoreline.

In March of this year the Association of State Floodplain Managers released a paper Flood Mapping for the Nation: A Cost Analysis for the Nation’s Flood Map Inventory  detailing funding needs to complete and maintain flood maps nationally.

VT DEC continues to express the acute need for map updates in Vermont.  Hopefully, as national coastal projects are finalized, FEMA can initiate work on inland riverine and lakeside flood maps.  Inadequate funding from Congress will prolong the absence of accessible and current data.  Data that is needed to plan for plan for community flood resilience, mitigate structures, and to correctly identify flood risk for insurance needs.