Data Management Plan (Deprecated)

Original Dataset Product: These lidar data are processed Classified LAS 1.4 files, formatted to 3799 individual 2640 ft x 2640 ft tiles clipped to the DPA; used to create 3D Breaklines and Hydro-Flattened DEMs as necessary. The classifications of the points are:

1 - Unclassified

2 - Ground

7 - Low Noise

9 - Water

17 - Bridge Deck

18 - High Noise

20 - Ignored Ground (Near breakline)

64 - Culvert

Original Dataset Geographic Extent: Solano county, California; covering approximately 905 square miles.

Original Dataset Description: The 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 meters. Project specifications are based on the U.S. Geological Survey National Geospatial Program Base Lidar Specification 2022, Revision A. The data was developed based on a horizontal projection/datum of NAD83(2011), California Zone 2 Feet, and vertical datum of NAVD88 (GEOID18) Feet. Lidar data was delivered as processed Classified LAS 1.4 files, formatted to 3799 individual 2640 ft x 2640 ft tiles clipped to the DPA, as tiled DEMs, as tiled DSMs, and as tiled DTMs; all tiled to the same 2640 ft x 2640 ft schema.

Original Dataset Collection Ground Conditions: Lidar was collected in February 2023, while no snow was on the ground and rivers were at or below normal levels. In order to post process the lidar data to meet task order specifications and meet ASPRS vertical accuracy guidelines, Sanborn Map Company, Inc. established a total of 23 ground control points that were used to calibrate the lidar to known ground locations established throughout the project area. An additional 103 independent accuracy check points, 56 in Bare Earth and Urban landcovers (56 NVA points), 47 in Tall Grass and Brushland/Low Trees categories (47 VVA points), were used to assess the vertical accuracy of the data. These check points were not used to calibrate or post process the data.

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 Entwine Point Tiles (EPT) hosted by USGS on Amazon Web Services.

Lineage Statement:
The NOAA Office for Coastal Management (OCM) ingested references to the USGS Entwine Point Tiles (EPT) hosted on Amazon Web Services (AWS) into the Digital Coast Data Access Viewer (DAV). The DAV accesses the point cloud as it resides on AWS under the usgs-lidar-public-container.

Process Steps:

• 2024-01-01 00:00:00 - The boresight was completed prior to project execution. The following steps describe the Raw Data Processing process: 1) Technicians processed the raw data to LAS format flight lines using the final GNSS/IMU solution. This LAS data set was used as source data for lidar matching. 2) Technicians utilized commercial and proprietary software packages to analyze how well flight line overlaps match for the entire lift and adjusted as necessary until the results met the project specifications. 3) Once all lifts were completed with lidar matching, the technicians checked and corrected the vertical misalignment of all flight lines and also the matching between data and ground truth. The relative accuracy was less than or equal to 6 cm RMSEz within individual swaths and less than or equal to 8 cm RMSEz or within swath overlap (between adjacent swaths). 4) The technicians ran a final vertical accuracy check of the flight lines against the surveyed check points after the z correction to ensure the requirement of NVA = 19.6 cm 95% Confidence Level (Required Accuracy) was met. Point classification was performed according to USGS Lidar Base Specification, and breaklines were collected for water features. Bare-earth DEMs were exported from the classified point cloud using collected breaklines for hydroflattening.
• 2024-01-01 00:00:00 - LAS Point Classification: The point classification is performed as described below. The bare-earth surface is then manually reviewed to ensure correct classification on the Class 2 (Ground) points. After the bare-earth surface is finalized, it is then used to generate all hydro-breaklines through heads-up digitization. All Class 2 (Ground) lidar data inside of the Lake Pond and Double Line Drain hydro-flattened breaklines were then classified to Class 9 (Water) using LP360 functionality. A buffer of 1 ft was also used around each hydro-flattened feature to classify these Class 2 (Ground) points to Class 20 (Ignored Ground). All Lake Pond Island and Double Line Drain Island features were checked to ensure that the Class 2 (Ground) points were reclassified to the correct classification after the automated classification was completed. All data was manually reviewed and any remaining artifacts removed using functionality provided by LP360, TerraScan and TerraModeler. Global Mapper was used as a final check of the bare-earth dataset. GeoCue was then used to create the deliverable industry-standard LAS files. Sanborn Map Company, Inc. proprietary software was used to perform final statistical analysis of the classes in the LAS files, on a per tile level to verify final classification metrics and full LAS header information.
• 2024-01-01 00:00:00 - Data was tested at 0.25 meter aggregate nominal pulse spacing and at 16.6 aggregate points per meter. The aggregate nominal pulse spacing was tested on classified tiled LAS using geometrically reliable first-return points. ANPS was tested using Delaunay Triangulation that produced average point spacing between all nearest neighbors.
• Original point clouds in LAS/LAZ format were restructured as Entwine Point Tiles and stored on Amazon Web Services. The data were re-projected horizontally to WGS84 web mercator (EPSG 3857) and the vertical units were converted to NAVD88 (Geoid18) meters.
• 2025-02-06 00:00:00 - The NOAA Office for Coastal Management (OCM) created references to the Entwine Point Tiles (EPT) that were ingested into the NOAA Digital Coast Data Access Viewer (DAV). No changes were made to the data. The DAV will access the point cloud as it resides on Amazon Web Services (AWS) under the usgs-lidar-public container. This is the AWS URL being accessed: https://s3-us-west-2.amazonaws.com/usgs-lidar-public/CA_SolanoCounty_1_A23/ept.json

Data is available online for bulk and custom downloads.

Data is backed up to cloud storage.