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This data set represents the 2-foot contour component of a digital terrain model (DTM) for the Florida Division of Emergency Management's (FDEM) Project Management and Technical Services for Mapping within Coastal Florida, encompassing Duval County, Florida. The complete digital terrain model is comprised of mass points, 2-D and 3-D breakline features, 1-foot and 2-foot contours, ground control, vertical test points, and a footprint of the data set, in the ESRI ArcGIS File Geodatabase format. In accordance with the Baseline Specifications 0.9, the following breakline features are contained within the database: closed water bodies (lakes, reservoirs, etc) as 2-D or 3-D polygons; linear hydrographic features (streams, shorelines, canals, swales, embankments, etc) as 3-D breaklines; coastal shorelines as 2-D or 3-D linear features; edge of pavement road features as 3-D breaklines; soft features (ridges, valleys, etc.) as 3-D breaklines; low confidence areas as 2-D polygons; island features as 2-D or 2D polygons; overpasses and bridges as 3-D breaklines. Contours were generated from a gridded DEM: 2-foot contours meet National Map Accuracy Standards, with 1-foot contours for visualization purposes. The LiDAR masspoints are delivered in the LAS file format based on the FDEM's 5,000' by 5,000' grid. Breakline features were captured to develop a hydrologically correct DTM. Bare earth LiDAR masspoint data display a vertical accuracy of at least 0.3-feet root mean square error (RMSE) in open unobscured areas. |