2018 USGS Lidar DEM: Upper St. Johns, FL eng Dataset EARTH SCIENCE > LAND SURFACE > TOPOGRAPHY > TERRAIN ELEVATION EARTH SCIENCE > LAND SURFACE > TOPOGRAPHY > TERRAIN ELEVATION > DIGITAL ELEVATION/TERRAIN MODEL (DEM) EARTH SCIENCE > OCEANS > COASTAL PROCESSES > COASTAL ELEVATION elevation CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > FLORIDA VERTICAL LOCATION > LAND SURFACE LIDAR > Light Detection and Ranging Airplane > Airplane Original Product: These are Digital Elevation Model (DEM) data for Upper St. Johns LiDAR as part of the required deliverables for the 2018 Upper St. Johns LiDAR project. Class 2 (ground) lidar points in conjunction with the hydro breaklines were used to create a 2.5 feet hydro-flattened Raster DEM. Original Geographic Extent: Upper St. Johns LiDAR, covering approximately 687 square miles. Original Dataset Description: Upper St. Johns 2018 LiDAR project called for the Planning, Acquisition, processing and derivative products of lidar data to be collected at a nominal pulse spacing (NPS) of 0.25 meter. Project specifications are based on the U.S. Geological Survey National Geospatial Program Base Lidar Specification, Version 1.2. The data was developed based on a horizontal projection/datum of NAD83 (2011), State Plane Florida East, U.S. survey feet and vertical datum of NAVD88 (GEOID12B), U.S. survey feet. Lidar data was delivered as processed Classified LAS 1.4 files, formatted to 973 individual 5000 ft x 5000 ft tiles, as tiled Intensity Imagery, and as tiled bare earth DEMs; all tiled to the same 5000 ft x 5000 ft schema. Original Dataset Ground Conditions: Lidar was collected in early 2018, while rivers were at or below normal levels. In order to post process the lidar data to meet task order specifications and meet ASPRS vertical accuracy guidelines, Dewberry established a total of 30 ground control points that were used to calibrate the lidar to known ground locations established throughout the Upper St. Johns LiDAR project area. An additional 90 independent accuracy checkpoints, 50 in Bare Earth and Urban landcovers (50 NVA points), 40 in Tall Grass and Brushland/Low Trees categories (40 VVA points), were used to assess the vertical accuracy of the data. These checkpoints were not used to calibrate or post process the data. This metadata record supports the data entry in the NOAA Digital Coast Data Access Viewer (DAV). For this data set, the DAV is leveraging the GeoTIFF files hosted by USGS on Amazon Web Services. OCM Partners OCM Partners https://www.fisheries.noaa.gov/inport/item/76110 https://www.fisheries.noaa.gov/inport/item/49404 https://www.fisheries.noaa.gov/inport/item/59708 northlimit=28.900197; eastlimit=-80.659865; southlimit=28.088417; westlimit=-81.113032; start=2018-03-21; end=2018-06-13; None 2018-12-01