Data Management Plan

Original Dataset Product: Classified LAS 1.4 files, formatted to 428 individual 1000m x 1000m tiles covering the Santiam River Topobathy project area.

Original Dataset Geographic Extent: This dataset and derived products encompass an area covering approximately 18,042 acres of Central Cascades in Oregon.

Original Dataset Description: The Santiam River Topobathy Lidar project called for the planning, acquisition, and processing of topobathy Lidar data collected to Quality Level 1 (QL1) standards for NIR, Quality Level 2b (QL2b) standards for green. Project specifications are based on the U.S. Geological Survey National Geospatial Program Lidar Base Specification Version 2022, Revision A. The data was developed based on the NAD83 2011 horizontal datum and the NAVD88 Geoid 18 vertical datum. Data was projected in UTM Zone 10. Lidar data was delivered as calibrated and classified LAS 1.4 files. Non-Vegetated Vertical Accuracy (NVA) was assessed using 25 check points located on bare earth in clear, unobstructed areas. Submerged Topography accuracy was assessed using 433 check points collected as feasible in depths up to 1m. Vegetated Vertical Accuracy (VVA) was assessed using 11 check points in Tall Grass, Forest, and Shrub landcover types. Single swath nominal pulse spacing (NPS) was designed to be 0.35 at nadir. Aggregate Nominal Pulse Spacing (ANPS) was calculated to be 0.18 using all valid first return points. Derived products include: Intensity Imagery, Topbathymetric Digital Elevation Models (DEMs), Maximum Surface Height Rasters (DSMs), waters edge breaklines, and a bathymetric void shape.

Original Dataset Ground Condition: Ground condition was free of snow and acquisition occurred free of smoke, fog and cloud cover

This metadata supports the data entry in the NOAA Digital Coast Data Access Viewer (DAV). The NOAA Office for Coastal Management (OCM) downloaded the laz files from the USGS rockyweb site and processed the data to make it available for bulk and custom downloads from the NOAA Digital Coast Data Access Viewer (DAV).

Lineage Statement:
The NOAA Office for Coastal Management (OCM) downloaded the laz files from the USGS rockyweb site and processed the data to make it available for bulk and custom downloads from the NOAA Digital Coast Data Access Viewer (DAV).

Process Steps:

• 2023-12-15 00:00:00 - Lidar Pre-Processing: 1. Review flight lines and data to ensure complete coverage of the study area and positional accuracy of the laser points. 2. Resolve kinematic corrections for aircraft position data using kinematic aircraft GPS and static ground GPS data. 3. Develop a smoothed best estimate of trajectory (SBET) file that blends post-processed aircraft position with sensor head position and attitude recorded throughout the survey. 4. Calculate laser point position by associating SBET position to each laser point return time, scan angle, intensity, etc. Create raw laser point cloud data for the entire survey in *.las format. Convert data to orthometric elevations by applying a Geoid 18 correction. 5. Apply refraction correct to bathymetric returns by flightline. 6. Import raw laser points into manageable blocks to perform manual relative accuracy calibration and filter erroneous points. Classify ground points for individual flight lines. 7. Using ground classified points per each flight line, test the relative accuracy. Perform automated line-to-line calibrations for system attitude parameters (pitch, roll, heading), mirror flex (scale) and GPS/IMU drift. Calculate calibrations on ground classified points from paired flight lines and apply results to all points in a flight line. Use every flight line for relative accuracy calibration. 8. Adjust the point cloud by comparing ground classified points to supplemental ground control points.
• 2023-12-15 00:00:00 - Lidar Post-Processing: 1. Classify data to ground and other client designated classifications using proprietary classification algorithms. 2. Manually QC data classification 3. After completion of classification and final QC approval, calculate final NVA, VVA, and density information for the project using ground control quality check points.
• 2024-12-26 00:00:00 - The Office for Coastal Management (OCM) downloaded laz files from the USGS rockyweb site for the Santiam River, OR topobathy dataset. The data were in UTM Zone 10N, NAD83(2011), meters coordinates and NAVD88 (Geoid18) elevations in meters. The points were classified as 1- Unclassified, 2 - Ground, 7 - Low Noise, 9 - Water, 17 - Bridge Deck, 18 - High Noise, 20 - Ignored Ground near breakline, 40 - Bathymetric Bottom, 41 - Water Surface, 45 - Water Column. The classes available on DAV are: 1, 2, 9, 17, 20, 40, 41, 42, 45. OCM performed the following processing on the data for Digital Coast storage and provisioning purposes: 1. Internal OCM scripts were run to check the number of points by classification and by flight ID and the gps, elevation, and intensity ranges. 2. Internal OCM scripts were run on the laz files to: a. Convert from orthometric (NAVD88) elevations in meters to NAD83 (2011) ellipsoid elevations in meters using the Geoid18 model b. Convert the laz files from UTM Zone 10N, NAD83(2011), meters coordinates to geographic coordinates c. Assign the geokeys, sort the data by gps time and zip the data to database

Data is available online for bulk and custom downloads.

Data is backed up to cloud storage.