2015 OLC Lidar DEM: Harney Basin, OR

This bare earth digital elevation model (DEM) represents the earth's surface with all vegetation and human-made structures removed in the OLC Harney Basin project area. Bare earth DEMs were derived from LiDAR data using TIN processing of the ground point returns. The DEM grid cell size is one meter. The projection is Universal Transverse Mercator (UTM) 11 North, and the units are meters. See Process Steps for derivation of raster datasets.

The dataset encompasses 634 square miles in portions of Harney County in the state of Oregon. The bare earth digital elevation model (DEM) represents the earth's surface with all vegetation and human-made structures removed. The bare earth DEMs were derived from lidar data using TIN processing of the ground point returns. The grid cell size is 1 meter. The projection is Universal Transverse Mercator (UTM) 11 North, and the units are meters. The horizontal datum is NAD 83 (2011) and vertical datum is NAVD88 (Geoid 12A). Some elevation values have been interpolated across areas in the models where there is no elevation data (e.g. over water, over dense vegetation). Watershed Sciences, Inc. collected the lidar and created this data set for the Oregon Department of Geology and Mineral Industries (DOGAMI).

This dataset provides high resolution terrain elevation and land cover elevation data in the OLC Harney Basin project area.

xyz location information for objects in the area

This dataset was contracted by Oregon Department of Geology and Mineral Industries (DOGAMI). Information regarding the use of this dataset should be directed to the owner.

Any conclusions drawn from the analysis of this information are not the responsibility of NOAA, the Office for Coastal Management or its partners

Data is available online for custom downloads

None

Users should be aware that temporal changes may have occurred since this data set was collected and some parts of this data may no longer represent actual surface conditions. Users should not use this data for critical applications without a full awareness of its limitations.

Vertical accuracy compares the delivered bare-earth digital elevation models (DEMS) with independent ground check points (GCPs) collected by DOGAMI staff. These variations in elevation values were used to produce a mean vertical error and vertical root mean square error (RMSE) value for the entire delivered data set. Project specifications list the maximum acceptable mean vertical offset to be 0.20 meters (0.65 feet) and the maximum vertical RSME to not exceed 0.0925 meters (0.303 feet). A total of 3909 independently measured GCP's were obtained in the OLC Harney Basin project area. The data delivered to DOGAMI was found to have a mean vertical offset of -0.033 meters (-0.107 feet) and an RMSE value of 0.058 meters (0.190 feet).

Data set was found to be complete. See the Acceptance Report for more detailed information.

The approach adopted for DOGAMI lidar surveys was comprised of three components:

1) Verify the horizontal and vertical coordinates established by Watershed Sciences for a select number of survey monuments used to calibrate the lidar survey. These surveys typically involved a minimum of two hours of GPS occupation over a known point. The collected data were then submitted to the National Geodetic Survey (NGS) Online Positioning User Service (OPUS) for post-processing against several Continuously Operating Reference Stations (CORS) operated by the NGS.

2) Collect GCP's along relatively flat surfaces (roads, paths, parking lots etc.). This step involved the collection of both continuous measurements (from a vehicle as well as from a backpack) as well as static measurements (typically 5 epochs).

3) Having collected the GCP data, the GPS data was post-processed using Trimble Business Center software. Data post-processing typically involved calibrations against at least three CORS stations as well as from local site calibrations performed in the field using those benchmarks that had been independently verified. Data is post processed to refine measurements so that horizontal and vertical errors are less than 0.02 meters (0.065 feet). Horizontal accuracy of data is tested by reoccupying a sample subset of survey monuments used for processing of lidar data. Each occupation's x and y coordinates are compared with the vendor coordinates for offsets.

Data is backed up to tape and to cloud storage.

Watershed Sciences Inc. has collected Light Detection and Ranging (LIDAR) data in the Milton-Freewater Study Area for the Oregon Department of Geology and Mineral Industries (DOGAMI).

NOAA OCM has taken the data and ingested it into the Digital Coast Data Access Viewer for distribution.