Data Management Plan

Product: Processed, classified lidar point cloud data tiles in LAS 1.4 format.

Geographic Extent: Approximately 12.6 square miles across the Salinas Quality Level 1 (QL1) Area of Interest (AOI) in Western California, this AOI is part of the broader FEMA R9 collection of approximately 10,547 square miles across 11 AOIs in California and Arizona.

Dataset Description: The CA FEMA R9 Lidar QL1 lidar project called for the planning, acquisition, processing, and production of derivative products of lidar data to be collected at a nominal pulse spacing (NPS) of 0.35 meters. Project specifications were based on the U.S. Geological Survey National Geospatial Program Base Lidar Specification, Version 1.2. The data was developed based on a horizontal datum/projection of NAD83 (2011) State Plane California IV (FIPS Zone 0404), US Survey Feet, and a vertical datum of NAVD88 (GEOID12B), US Survey Feet. Lidar data was delivered as processed LAS 1.4 files formatted to 41 individual 4,500-feet x 4,500-feet tiles.

Ground Conditions: Lidar was collected from February 16, 2018 through February 18, 2018 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, Woolpert established 148 ground control points across all California AOIs that were used to calibrate the lidar to known ground locations established throughout the project area. An additional 258 independent accuracy checkpoints (145 NVA points and 113 VVA points), were collected across all California AOIs and used to assess the vertical accuracy of the data. These checkpoints were not used to calibrate or post process the data.

Process Steps:

• 2019-03-14 00:00:00 - Lidar Point Cloud Classification: The point cloud underwent a classification process to determine bare-earth points and non-ground points utilizing "first and only" as well as "last of many" lidar returns. This process determined Processed, but Unclassified (Class 1), Bare Earth Ground (Class 2), Low Noise (Class 7), Water (Class 9), Ignored Ground (Class 10), Bridge Decks (Class 17) and High Noise (Class 18). The bare-earth (Class 2 Ground) lidar points underwent a manual QA/QC step to verify the quality of the DEM as well as a peer-based QC review. This included a review of the DEM surface to remove artifacts and ensure topographic quality. After the bare-earth surface is finalized, it is then used to generate all hydro-breaklines through a semi-automated process. All ground (Class 2) lidar data inside of the Lake Pond and Double Line Drain hydro flattening breaklines were then classified to water (Class 9) using TerraScan/LP360 macro functionality. A buffer of 1.14 feet was also used around each hydro-flattened feature to classify these ground (Class 2) points to Ignored ground (Class 10). All Lake Pond Island and Double Line Drain Island features were checked to ensure that the ground (Class 2) points were reclassified to the correct classification after the automated classification was completed. All overlap data was processed through automated functionality provided by TerraScan to classify the overlapping flight line data to approved classes by USGS. The overlap data was classified using standard LAS overlap bit. These classes were created through automated processes only and were not verified for classification accuracy. Due to software limitations within TerraScan, these classes were used to trip the withheld bit within various software packages. These processes were reviewed and accepted by USGS through numerous conference calls and pilot study areas. All data was manually reviewed and any remaining artifacts removed using functionality provided by 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 for both the All Point Cloud Data and the Bare Earth. Woolpert proprietary software and LP360 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.
• 2021-03-30 00:00:00 - The NOAA Office for Coastal Management (OCM) downloaded the laz files from this USGS site: ftp://rockyftp.cr.usgs.gov/vdelivery/Datasets/Staged/Elevation/LPC/Projects/CA_AZ_FEMA_R9_Lidar_2017_D18/ These files were processed to the Data Access Viewer (DAV) and https. The total number of files downloaded and processed was 41. The data were in California State Plane Zone 4 (NAD83 2011), US Survey Feet, coordinates and NAVD88 (Geoid12B) elevations in US Survey Feet. The data were classified as: 1 - Unclassified, 2 - Ground, 7 - Low Noise, 9 - Water, 17 - Bridge Decks, 18 - High Noise. OCM processed all classifications of points to the Digital Coast Data Access Viewer (DAV). OCM performed the following processing on the data for Digital Coast storage and provisioning purposes: 1. An internal OCM script was run to check the number of points by classification and by flight ID and the gps and intensity ranges. 2. Internal OCM scripts were run on the laz files to convert from orthometric (NAVD88) elevations to ellipsoid elevations using the Geoid12B model, to convert from CA State Plane (NAD83 2011) coordinates to geographic coordinates, to assign the geokeys, to sort the data by gps time, to filter points below -10 feet and zip the data to database and to http.

Data is available online for bulk or custom downloads

Data is backed up to tape and to cloud storage.