Data Management Plan (Deprecated)

GPI Geospatial Inc., operating under the authority of Miami-Dade County Aviation Department, as per contract number E15-MDAD-01, has been tasked by Miami-Dade County's Information Technology Department (ITD) to provide LiDAR data for 615 square miles, including the classification of the data and the creation of hydro-flattened Digital Elevation Model (DEM). GPI Geospatial has created a file geodatabase named 2021_Lidar.gdb. The project deliverables included fully compliant LAS v1.4 with georeferenced information included in LAS header. The LAS files have 16-bit intensity values with GPS times recorded as Adjusted GPS Time, at a precision sufficient to allow unique timestamps for each return. The LiDAR classification followed the ASPRS Standards LIDAR Point Classes: 1 = Unclassified; 2 = Ground (or Bare Earth); 3 = Low Vegetation 0 -5ft; 4 = Medium Vegetation 5-25ft; 5 = High Vegetation 25-above; 6 = Building; 7 = Low Point (noise); 8 = Model Key-point (mass point); 9 = Water; 17 = Bridges; 18 = High Noise; 20 = Ignored Ground.

Mass points deliverable LAS v1.4 with georeferenced information included in LAS header. The mass point files have 16-bit intensity values with GPS times recorded as Adjusted GPS Time, at a precision sufficient to allow unique timestamps for each return. The LAS files and mass points were tiled, without overlap, following FDOR tiling grid with 16 sub-tiles provided by Miami Dade County's Information Technology Department (ITD).

The Miami-Dade County Information Technology Department (ITD) provided the NOAA Office for Coastal Management (OCM) with a copy of the las point data to make the data available for custom download from the NOAA Digital Coast Data Access Viewer (DAV) and for bulk download from AWS S3. This metadata record describes that data.

Lineage Statement:
The NOAA Office for Coastal Management (OCM) received 10,904 LAS files from the Miami-Dade County Information Technology Department (ITD).

Process Steps:

• 2021-07-06 00:00:00 - The project was divided in two phases: Collection and classification of LiDAR data; and creation of 5-foot and 2-foot cell spaced hydro flattened mosaic DEM of the project area. The LiDAR data was collected utilizing a Riegl VQ-1560ii in a Cessna 206 from an approximate altitude of 4,200 feet above ground level, at an approximate ground speed of 110 knots at a pulse rate repetition of 3,592 kHg, resulting in an average of 28 points per square meter single swath. Three areas needed reflight's due to clouds and building shadows the flight height was lowered to get under the cloud celling in these areas. These areas were collected at 2,500 feet agl at 120 knots at a pulse rate repetition of 4,000kHg. These lines were collected at 50.6 points per square meter single swath. The sensor used a 60-degree field of view. The project was flown to have 30 percent overlap between swaths for original flight plan and 60% for the 2,500 foot altitude. The Global Positioning System (GPS) data were processed using Applanix POSPac Mapping Suite version 8.4 using Smart Base method and single base methods. A fixed bias carrier phase solution was computed in forward and reverse directions. The LiDAR collection took place when Positional Dilution of Precision (PDOP) was at or below 3. Occasionally, the PDOP rose slightly above 3. This had no effect on the data. The GPS trajectory was combined with the IMU data using the Applanix POSPac software. The resulting Smoothed Best Estimate of Trajectory (SBET) was exported and used in Riegl RiProcess software to compute the laser mass point positions in Northing, Easting, and Elevations coordinates. The raw laser data were merged with the SBET using Riegl RiProcess software. The data set was processed using RiProcess, RiAnalyze, and RiWorld software where each flight line was processed to a point cloud. The data was adjusted flight line to flight line using Riegl's Scan Data Adjustment tool to ensure a proper relative calibration match between flight lines. Each flight was checked for project coverage, data gaps between overlapping flight lines, point density and then exported in LAS 1.4 format. The entire project was collected without gaps. The LAS files were projected to the NAD_1983_2011_StatePlane_Florida_East_FIPS_0901_Feet and North American Vertical Datum of 1988 (NAVD88). Ellipsoidal heights were converted to orthometric heights using the current Geoid 18. The LAS files were imported to TerraSolid, LTD TerraScan software to be classified to bare earth ground and later feature coded to USGS specifications. The LAS files contain 12 classifications: 1 = unclassified; 2 = ground (or Bare Earth); 3 = low vegetation 0 - 5 ft; 4 = med veg 5 - 25 ft; 5 = high veg 25 - above; 6 = building; 7 = low point (noise); 9 = water; 17 = bridges; 18 = high noise; 20 = ignored ground. The LiDAR data was run through an automated ground and building classification using TerraScan software. A manual check of the building classification was done. The vegetation heights were assigned by an automated process after the bare-earth and buildings were classified. Breaklines were digitized from the LiDAR data in ArcMap
• 2025-05-29 00:00:00 - The NOAA Office for Coastal Management (OCM) received 10,904 LAS files from the Miami-Dade County Information Technology Department (ITD). The files were in Florida State Plane East NAD83(2011), US feet coordinates and the elevations were in NAVD88 (GEOID18) feet. The LAS files contain 11 classifications: 1 = unclassified; 2 = ground (or Bare Earth); 3 = low vegetation 0 - 5 ft; 4 = med veg 5 - 25 ft; 5 = high veg 25 ft and higher; 6 = building; 7 = low point (noise); 9 = water; 17 = bridges; 18 = high noise; 20 = ignored ground. OCM processed the 1, 2, 3, 4, 5, 6, 7, 9, 17, 18, and 20 point classes to the Digital Coast Data Access Viewer (DAV). OCM performed the following processing on the data for Digital Coast storage and provisioning purposes: 1. The data were converted to laz format using laszip 2. Internal OCM scripts were run to check the number of points by classification and by flight ID and the gps, elevation, and intensity ranges. 3. Internal OCM scripts were run on the laz files to: a. Convert from orthometric (NAVD88) elevations to ellipsoid elevations using the GEOID18 model b. Convert from FL State Plane East Zone 0901 (NAD83 2011), US survey foot coordinates to geographic coordinates c. Convert from vertical units of feet to meters d. Filter points outside the elevation range of -100 to 2000 feet e. Assign the geokeys, to sort the data by gps time and zip the data to database and to AWS S3.

Data is available online for bulk and custom downloads.

Data is backed up to cloud storage.