Data Management Plan

SWFWMD regularly uses digital topographic information to support regulatory, land management and acquisition, planning, engineering and habitat restoration projects. LiDAR data will support hydrologic modeling activities associated with the FederalEmergency Management Agency (FEMA), and in the creation of Digital Flood Insurance Rate Maps(DFIRM). The Light Detection and Ranging (LiDAR) LAS dataset is a survey of Lake Placid. The Lake Placid LiDAR Survey project area consists of approximately 44.8 miles. The LiDAR point cloud was flown at a density sufficient to support a maximum final post spacing of 4 feet for unobscured areas. 3001 Inc. acquired 38 flightlines on March 4, 2007. The data was divided into 5000' by 5000' cells that serve as the tiling scheme. The Lake Placid LiDAR Survey was collected under the guidance of a Professional Mapper/Surveyor.

Process Steps:

• 2007-01-01 00:00:00 - The ABGPS, inertial measurement unit (IMU), and raw scans are collected during the LiDAR aerial survey. The ABGPS monitors the xyz position of the sensor and the IMU monitors the orientation. During the aerial survey laser pulses reflected from features on the ground surface are detected by the receiver optics and collected by the data logger. GPS locations are based on data collected by receivers on the aircraft and base stations on the ground. The ground base stations are placed no more than 35 km radius from the flight survey area.
• 2007-01-01 00:00:00 - The ABGPS, IMU, and raw scans are integrated using proprietary software developed by the Leica Geosystems and delivered with the Leica ALS50 System. The resultant file is in a LAS binary file format. The LAS file version 1.1 format can be easily transferred from one file format to another. It is a binary file format that maintains information specific to the LiDAR data (return number, intensity value, xyz, etc.). The resultant points are produced in the Florida State Plane West Zone (0902) coordinate system, with units in feet and referenced to the NAD83/90 HARN horizontal datum and NAVD88 vertical datum.
• 2007-11-01 00:00:00 - The unedited data are classified to facilitate the application of the appropriate feature extraction filters. A combination of proprietary filters is applied as appropriate for the production of bare-earth digital terrain models (DTMs). Interactive editing methods are applied to those areas where it is inappropriate or impossible to use the feature extraction filters, based upon the design criteria and/or limitations of the relevant filters. These same feature extraction filters are used to produce elevation height surfaces.
• 2007-01-01 00:00:00 - Filtered and edited data are subjected to rigorous QA/QC according to the 3001 Inc. Quality Control Plan and procedures. Very briefly, a series of quantitative and visual procedures are employed to validate the accuracy and consistency of the filtered and edited data. Ground control is established by 3001, Inc. and GPS-derived ground control points (GCPs) points in various areas of dominant and prescribed land cover. These points are coded according to landcover, surface material and ground control suitability. A suitable number of points are selected for calculation of a statistically significant accuracy assessment as per the requirements of the National Standard for Spatial Data Accuracy. A spatial proximity analysis is used to select edited LiDAR data points within a specified distance of the relevant GCPs. A search radius decision rule is applied with consideration of terrain complexity, cumulative error and adequate sample size. Accuracy validation and evaluation is accomplished using proprietary software to apply relevant statistical routines for calculation of Root Mean Square Error (RMSE) and the National Standard for Spatial Data Accuracy (NSSDA) according to Federal Geographic Data Committee (FGDC) specifications.
• 2007-11-01 00:00:00 - The LiDAR mass points were delivered in American Society for Photogrammetry and Remote Sensing LAS 1.1 format. The header file for each dataset is complete as define by the LAS 1.1 specification. In addition the following fields are included: Flight Date Julian, Year, and Class. The LAS files do not include overlap. The data were classified as follows: Class 1 = Unclassified- this class includes vegetation, buildings, noise etc.; Class 2 = Ground; Class 9 = Water. The datasets were delivered in the 5000' by 5000' tiling scheme. The tiles are contiguous and do not overlap. The tiles are suitable for seamless topographic data mosaics that include no "no data" areas. The names of the tiles are left padded with zeros as required to achieve a five character length and all files utilize the LAS file extension.
• 2014-09-24 00:00:00 - The NOAA Office for Coastal Management (OCM) received the topographic lidar files in LAS format from SWFWMD. The files contained lidar easting, northing, elevation, intensity, return number, etc. The data was received in Florida State Plane West 0902 (US ft) and NAVD88 (US ft). OCM performed the following processing for data storage and Digital Coast provisioning purposes: 1. The files were reviewed and erroneous elevations were removed.

This data can be obtained on-line at the following URL:

https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=4695;