DGS, in cooperation with DNREC Delaware Coastal Programs, developed a series of coastal inundation maps corresponding to water surfaces from the mean higher-high water (MHHW) level to 7 feet above MHHW, in 1-foot increments. Development of the bathtub-model inundation maps was based on a high-quality, 1-meter Digital Elevation Model derived from the 2014 state-wide LiDAR acquisition funded jointly by DGS, DNREC, Delaware Department of Transportation and the USGS through Hurricane Sandy Supplemental Relief Funds. The final product of these analyses is a geodatabase containing eight layers (MHHW to MHHW + 7 ft) representing the bare-earth coastal inundation maps and eight layers showing the same regions with an accounting for elevated roadways and bridges. These maps and the updated SLR planning scenarios will help advise long-range planning of infrastructure, facilities, land management, land use, and capital spending.
Documentation describing the mapping methodology is attached below.
The map data are accessible through several avenues:
- Direct Connect to ArcGIS Map Services: The complete set of coastal inundation maps are being distributed as ArcGIS webmap services through Delaware FirstMap. The webmap services can be accessed directly from ArcGIS Desktop without the need to download the data locally to a computer first. The URL to access the data is: https://firstmap.delaware.gov/arcgis/rest/services/Environmental/DE_Coa…
- Online Map Viewer: This is probably the easiest and quickest way to view the maps. The ArcGIS Online Map Viewer displays each water surface layer over a standard base map. http://arcg.is/PjW10
- Data Download: The map data files, including both the ArcGIS 10.x MXD file and file geodatabase, are available from the DGS dataset collection pages. These data must be downloaded and unzipped to a local computer and accessed through ArcGIS Desktop 10.1 or greater. Data can be downloaded at http://www.dgs.udel.edu/datasets/delaware-coastal-inundation-maps
This project is supported using Federal funds under award NA13NOS4190093 from the Delaware Department of Natural Resources and Environmental Control (DNREC), Delaware Coastal Programs and the Office for Coastal Management (OCM), National Oceanic and Atmospheric Administration (NOAA), U.S. Department of Commerce. The statements findings, conclusions and recommendations are those of the author(s) and do not necessarily reflect the views of the OCM, NOAA or the U.S. Department of Commerce.