2017 - 2019 La DOTD Lidar DEM: Northeast Louisiana

Original Product: These are Digital Elevation Model (DEM) data for the Northeast Louisiana Lidar project. Class 2 (ground) lidar points in conjunction with the hydro breaklines were used to create a 0.5 meter hydro-flattened Raster DEM.

Original Geographic Extent: Covers approximately 5750 square miles in northeast Louisiana.

LA_NortheastDOTD_1 (Work Unit 197130) - covers approximately 511 square miles in Morehouse, Ouachita, Richland, and Union Parishes

LA_NortheastDOTD_2 (Work Unit 300053) - covers approximately 2010 square miles in East Carroll, Issaquena, Madison, Morehouse, Richland, Union, Warren, and West Carroll Parishes

LA_NortheastDOTD_3 (Work Unit 300054) - covers approximately 1364 square miles in Avoyelles, Caldwell, Catahoula, Franklin, Grant, LaSalle, Ouachita, Rapides, and Richland Parishes

LA_NortheastDOTD_4 (Work Unit 300055) - covers approximately 1865 square miles in Adams, Catahoula, Claiborne, Concordia, Franklin, Jefferson, Madison, Richland, Tensas, and Warren Parishes

Original Dataset Description: The Northeast Louisiana Lidar project called for the planning, acquisition, processing and derivative products of lidar data to be collected at a nominal pulse spacing (NPS) of 0.35 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), Universal Transverse Mercator, meters and vertical datum of NAVD88 (GEOID12B), meters. Lidar data was acquired and calibrated, classified LAS files were produced, formatted to individual 1500 m x 1500 m tiles, as tiled Intensity Imagery, and as tiled bare earth DEMs; all tiled to the same 1500 m x 1500 m schema.

Ground Conditions: Lidar was collected 2017 - 2019 with varying ground conditions.

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.

To acquire detailed surface elevation data for use in conservation planning, design, research, floodplain mapping, dam safety assessments and elevation modeling, etc. Classified LAS files are used to show the manually reviewed bare earth surface. This allows the user to create Intensity Images, Breaklines and Raster DEM. The purpose of these lidar data was to produce high accuracy 3D hydro-flattened Digital Elevation Model (DEM) with a 0.5 meter cell size. These raw lidar point cloud data were used to create classified lidar LAS files, intensity images, 3D breaklines, hydro-flattened DEMs as necessary.

Raster File Type = IMG

Bit Depth/Pixel Type = 32-bit float

Raster Cell Size = 0.5 Meter

Interpolation or Resampling Technique = Triangulated Irregular Network

Required Vertical Accuracy = 19.6 cm NVA

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

To the extent possible under law, the U.S. Government has waived all copyright and related or neighboring rights to this dataset.

Data is available online for bulk and 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.

This data set was produced to meet ASPRS Positional Accuracy Standard for Digital Geospatial Data (2014) for 10-cm RMSEz Vertical Accuracy Class.

USGS Determined DEM Vertical Accuracy:

Non-Vegetated Vertical Accuracy (NVA) = 5.97 cm RMSE

Vegetated Vertical Accuracy (VVA) = 21.43 cm at 95th Percentile

Datasets contain complete coverage of tiles. No points have been removed or excluded. A visual qualitative assessment was performed to ensure data completeness. There are no void areas or missing data. The raw point cloud is of good quality and data passes Non-Vegetated Vertical Accuracy specifications.

Data covers the entire area specified for this project.

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.