Top: A representative image of a lidar source point cloud. The data were collected by an airborne lidar instrument over Cannon Beach, Oregon, in 2008-2009. The Oregon Department of Geology and Mineral Industries (DOGAMI) acquired the data in partnership with multiple other organizations. When the 3D Elevation Program (3DEP) is fully realized, similar high-resolution lidar (light detection and ranging) data will be available for the entire conterminous United States and Hawaii. They will support many applications, including flood risk management, hazard mitigation, and natural resource management. The colors in this point cloud indicate elevation, from low (blue) to high (red). Bottom: Examples of top-down views of a suite of derivative products that all were generated from the above lidar point cloud by the U.S. Geological Survey. North is at the top of the page. A, Hillshade (shaded-relief) model, which is used for visualizing the terrain. B, Digital elevation model (bare-earth DEM), which is used for general topographic analysis and mapping. Lower areas are shown as green, and higher areas are shown as brown. The brown area at left is a feature called Haystack Rock. The DEM and hillshade model are both derived from the lidar classified point cloud by filtering points and interpolating between points. C, Slope (bare-earth) model, showing the vertical change from one bare-earth elevation cell to its neighbor. Steep slopes are shown as red, and flat areas are shown as green. D, Laser-intensity model, showing the strength of the laser signal returned from a lidar pulse. Laser-intensity models allow compilation of breaklines, such as ridges and shorelines. The curving line represents a road. E, Height-above-ground model, showing the vertical difference between the highest nonground return and the ground return. Tree-canopy heights and building footprints and their associated heights can easily be extracted from this derivative. The dark-blue line represents an area of no trees, where a powerline has been cut through.

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In January 2015, the U.S. Geological Survey National Geospatial Technical Operations Center began producing the 1-Meter Digital Elevation Model data product. This new product was developed to provide high resolution bare-earth digital elevation models from light detection and ranging (lidar) elevation data and other elevation data collected over the conterminous United States (lower 48 States), Hawaii, and potentially Alaska and the U.S. territories. The 1-Meter Digital Elevation Model consists of hydroflattened, topographic bareearth raster digital elevation models, with a 1-meter x 1-meter cell size, and is available in 10,000-meter x 10,000-meter square blocks with a 6-meter overlap. This report details the specifications required for the production of the 1-Meter Digital Elevation Model.

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The US Topo is a new generation of digital topographic maps delivered by the US Geological Survey (USGS). These maps include contours in the traditional 7.5-min quadrangle format. The process for producing digital elevation contours has evolved over several years, but automated production of contours for the US Topo product began in 2010. This process, which is quite complex yet fairly elegant, automatically chooses the proper USGS quadrangle, captures the corresponding 1/3 as grid points from the national elevation data set (3D Elevation Program), and adjusts elevation data to better fit water features from the National Hydrography Dataset. After additional processing, such as identifying and tagging depressions, constructing proper contours across double-line streams, and omitting contours from water bodies, contours are automatically produced for the quadrangle. The resulting contours are then compared to the contours on the original (legacy) topographic map sheets, or to the 10-m contours from the original map sheets. Where the elevation surface used to generate the contours has been derived from the previously published contours for a quadrangle, the generated contours match the legacy contours quite well. Where newer elevation sources, such as lidar, originate the elevation surface, generated contours may vary significantly from the previous cartographically produced contours due to more accurate representations of the surface, and less reliance on cartographic interpretation.