Coastal Storm Surge Analysis System Digital Elevation Model: Report 1: Intermediate Submission No. 1.1

The Federal Emergency Management Agency, Region III office, has initiated a study to update the coastal storm surge elevations within the states of Virginia, Maryland, and Delaware, and the District of Columbia including the Atlantic Ocean, Chesapeake Bay and its tributaries, and the Delaware Bay. This effort 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 world. The study will replace outdated coastal storm surge stillwater elevations for all Flood Insurance Studies in the study area, and serve as the basis for new coastal hazard analysis and ultimately updated Flood Insurance Rate Maps (FIRMs). Study efforts were initiated in August of 2008, and are expected to conclude in 2010. The storm surge study will utilize the Advanced Circulation Model for Oceanic, Coastal and Estuarine Waters (ADCIRC) for simulation of 2-dimensional hydraulics. ADCIRC will be coupled with 2-dimensional wave models to calculate the combined effects of surge and wind-induced waves. A seamless modeling grid was developed to support the storm surge modeling efforts. This report, the first of three reports comprising the required Submittal 1 documentation, provides a detailed overview of the construction of the Digital Elevation Model, modeling mesh, and the development of an integrated computational system for FEMA Region III storm surge modeling. The original document contains color images.