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This polyline layer is the coastal profile line that was used to derive inundation surfaces from. It was manually drawn oriented north to south along the New England coastline beginning in Portland Maine and ending in Eastham Massachusetts. The coastal profile line covers the geographic extent of collected USGS surveyed high water mark and storm sensor data as well as the location of USGS coastal tide gages for stillwater data points. The Storm_Event_Data_Points layer were snapped to the closest location along the coastal profile line and given a stationing measurement. The elevation values were used to calculate a linear relationship between stationing and elevation. The centroids of all coastal HUC12 basins were then snapped to the coastal profile line to derive an elevation value based on stationing for the snapped centroids for each storm event and USGS stillwater data. These HUC12 centroid elevations were joined back to the HUC12 polygon layer to estimate and delineated a water surface elevation inside each HUC12 polygon along the New England coastline.