Description: Areas subject to potential increased risk due to storm induced erosion from Hurricanes Irma and Maria were identified in this task. These areas were identified by a visual review of Vexcel Imagery, dated October 2017, and NOAA Imagery dated September 2017, compared to the shoreline delineated from pre-storm 2013 NOAA LiDAR surveys and available pre-storm imagery. Pre-storm imagery was sourced from NOAA Digital Coast and Google Earth. Areas of apparent storm induced erosion were identified by manually drawn polygons capturing three types of coastal erosion processes: erosion, deposition, and overwash. Polygons are bounded the extent of the area subject to erosion
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Description: Areas of potential storm induced erosion were identified though an analysis of modeled erosion, completed using the effective FIS study by creating a polygon coverage to identify areas of non-standard erosion. Polygons were bounded by the updated shoreline from this study and the extent of the area subject to erosion
Description: The Streams file is intended to serve as the location of flooding source where the ABFEs were analyzed and further used in the Hydraulic analysis.
Description: This shoreline is a polyline representation of the zero-foot VIVD09 topographic contour line for the islands of St. Croix, St. John, and St. Thomas. It represents the seaward extent of the topographic data used in creating the FEMA post-Hurricane Maria Virgin Islands Advisory products.
Description: The Federal Emergency Management Agency (FEMA) has developed the Advisory Limit of the 1% Flood Hazard Area and 0.2% Flood Hazard Area to provide a geospatial limit to the Advisory Base Flood Elevations.
Description: The CrossSections are intended to provide information on flooding source and water surface elevations for 10%, 4%, 2%, 1%, 1%, and 0.2% flood events. These cross sections represent the most conservative riverine BFE from either the 2009 effective FIRM study or the new advisory modeling.
Description: The Federal Emergency Management Agency (FEMA) has developed the Advisory Flood Zones. They provide full geospatial representation of the coastal and riverine Advisory Base Flood Elevations (1% annual chance coastal flood hazard), including both storm surge and wave components. FEMA is providing an advisory floodway to provide a geospatial limit of the channel of rivers or other watercourse and the adjacent land areas that must be reserved in order to discharge the base flood without cumulatively increasing the water surface elevation more than the designated height.