2020 DOGAMI Lidar DEM: South Coast, OR

Original Dataset Product: This GIS dataset contains Bare Earth (BE) raster grids depicting lidar-derived elevation data for 2020 Oregon Lidar Consortium South Coast 3DEP project area.

Points that were determined to be geometrically invalid, or invalid surface returns, were removed from the data set. The nominal pulse density is eight pulses per square meter. The bare earth (BE) digital elevation model (DEM) raster grid cell size is 3 feet. The native projection is Lambert Conic Conformal, units are in International feet. The native horizontal datum is North American Datum of 1983 (NAD83(2011)); the native vertical datum is North American Vertical Datum of 1988 (NAVD88); (Geoid 12B). NV5 Geospatial collected the lidar and created this dataset in partnership with the Oregon Department of Geology and Mineral Industries (DOGAMI). Ocean water was not classed as water or hydroflattened to preserve offshore terrain.

Original Dataset Geographic Extent: Coos County, Curry County, Josephine County, and Douglas County, Oregon, covering approximately 1,729,680 acres.

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.

This dataset provides high resolution elevation data that is used to produce three-dimensional models of the earth surface for the purpose of managing natural resources and mapping natural hazards.

CONTRACTOR: NV5 Geospatial

All ground survey data, Lidar data acquisition, calibration, and follow-on processing were completed by the prime contractor, NV5 Geospatial

Users should be aware that temporal changes may have occurred since this dataset was collected and that some parts of these data may no longer represent actual surface conditions. Users should not use this data for critical applications without a full awareness of its limitations. This product is for informational purposes and may not have been prepared for or be suitable for legal, engineering, surveying, or site specific purposes. Users of this information should review or consult the primary data and information sources to ascertain the usability of the information. Acknowledgment of Oregon Department of Geology and Industries (DOGAMI) would be appreciated for products derived from these data.

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 bulk and custom downloads.

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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.

LiDAR Mapping Suite 2.4, Applanix PosPac 7.1, Microstation Connect, TerraScan Version 19, TerraModeler Version 19, TerraMatch Version 19, ESRI ArcGIS 10.3.1, Windows 10 Operating System

For this delivery, the Raw Swath NVA was tested with checkpoints located in bare earth and urban (non-vegetated) areas within the delivery area. These checkpoints are not used in the calibration or post processing of the lidar point cloud data. The checkpoints are distributed throughout the project area and surveyed using GPS techniques. See survey report for additional survey methodologies. Elevations from the unclassified lidar surface are measured for the x,y location of each check point. Elevations interpolated from the lidar surface are then compared to the elevation values of the surveyed control points. AccuracyZ is tested to meet 19.6 cm or better Non-Vegetated Vertical Accuracy at 95% confidence level using RMSE(z) x 1.9600 as defined by the National Standards for Spatial Data Accuracy (NSSDA); assessed and reported using National Digital Elevation Program (NDEP)/ASRPS Guidelines. Cumulative NVA and VVA are reported for the entire DPA.

The project specifications require the accuracy (ACCz) of the derived DEM be calculated and reported in two ways: 1. The required NVA is: 19.6 cm or better at a 95% confidence level, derived according to NSSDA, i.e., based on RMSE of 10 cm in the "bare earth" and "urban" land cover classes. This is a required accuracy. The Bare Earth DEM NVA is tested with checkpoints located in bare earth and urban (non-vegetated) areas; the 2. Vegetated Vertical Accuracy (VVA): VVA is reported for "forested", "shrub", and "tall grass" land cover classes within delivery area. The target VVA is: 29.4 cm at the 95th percentile, derived according to ASPRS Guidelines, Vertical Accuracy Reporting for Lidar Data, i.e., based on the 95th percentile error in all vegetated land cover classes combined. This is a target accuracy. The VVA is tested with checkpoints located in vegetated areas. The checkpoints are distributed throughout the project area and are surveyed using GPS techniques. See survey report for additional survey methodologies.

USGS DEM Determined Vertical Accuracy:

Non-Vegetated Vertical Accuracy (NVA) = 5.04 cm RMSE

Vegetated Vertical Accuracy (VVA) = 17.58 cm at 95th Percentile

A visual qualitative assessment was performed to ensure data completeness. No void areas or missing data exist.

Data covers the area specified for this project.

Data is backed up to cloud storage.

The NOAA Office for Coastal Management (OCM) ingested references to the USGS GeoTIFF files that are hosted on Amazon Web Services (AWS), into the Digital Coast Data Access Viewer (DAV). The DAV accesses the raster data as it resides on AWS.