Data Management Plan (Deprecated)

EarthData International collected ALS-50-derived LiDAR over Upper Myakka Florida with a one-meter post spacing. The

period of collection was between 3 October and 12 October 2006. This data set falls in Manatee County. The collection was

performed by EarthData Aviation, using a Leica ALS-50 LiDAR system, including an inertial measuring unit (IMU) and a dual

frequency GPS receiver. This project required six lifts of flight lines to be collected. The product generated consisted of

LiDAR bare earth elevation models in LAS format. This data set is one component of a digital terrain model (DTM) for the

Southwest Florida Water Management District's FY2005 Digital LiDAR Project (H048), encompassing approximately 291 square

miles across Manatee County. The 2005 LiDAR dataset is comprised of 3-D mass points delivered in the LAS file format based

on the District's 5,000' by 5,000' grid (325 cells). The other DTM component is 2-D and 3-D breakline features in the ESRI

ArcGIS Personal Geodatabase format. In accordance with the 2005 SWFWMD Topographic Database Design, the following breakline

closed water bodies (lakes, reservoirs, etc) as 3-D polygons; linear hydrographic features (streams, canals, swales,

embankments, etc) as 3-D breaklines; coastal shorelines as 3-D linear features; edge of pavement road features as 3-D

breaklines; soft features (ridges, valleys, etc.) as 3-D breaklines; obscured vegetation polygons as 2-D polygons; overpasses

and bridges as 3-D breaklines; 1-foot contours for visualization purposes; and island features as 3-D polygons. Breakline

features were captured to develop a hydrologically correct DTM. Contours (1-foot) were generated from the DTM that meet the

National Map Accuracy Standards for 2-foot contours (FEMA specifications). Bare earth LiDAR mass point data display a vertical

accuracy of at least 0.3-feet root mean square error (RMSE) in open unobscured areas.

Original contact information:

Contact Name: Mapping and GIS section

Contact Org: Southwest Florida Water Management District

Phone: 352.796.7211

Process Steps:

• 2006-11-15 00:00:00 - The airborne GPS data were processed and integrated with the IMU. The results were imported into the processing system for use in the LiDAR boresight. The raw LiDAR data was downloaded onto a production server. The ground control and airport GPS base station were used in conjunction with the processed ABGPS results for the LiDAR boresight. The properly formatted processing results were used for subsequent processing.
• 2007-01-15 00:00:00 - EarthData has developed a unique method for processing LiDAR data to identify and remove elevation points falling on vegetation, buildings, and other aboveground structures. The algorithms for filtering data were utilized within EarthData's proprietary software and commercial software written by TerraSolid. This software suite of tools provides efficient processing for small to large-scale, projects and has been incorporated into ISO 9001 compliant production work flows. The following is a step-by-step breakdown of the process. 1. Using the LiDAR data set provided by EarthData Aviation, the technician performs calibrations on the data set. 2. The technician performed a visual inspection of the data to verify that the flight lines overlap correctly. The technician also verified that there were no voids, and that the data covered the project limits. The technician then selected a series of areas from the data set and inspected them where adjacent flight lines overlapped. These overlapping areas were merged and a process which utilizes 3-D Analyst and EarthData's proprietary software was run to detect and color code the differences in elevation values and profiles. The technician reviewed these plots and located the areas that contained systematic errors or distortions that were introduced by the LiDAR sensor. 3. Systematic distortions highlighted in step 2 were removed and the data was re-inspected. Corrections and adjustments can involve the application of angular deflection or compensation for curvature of the ground surface that can be introduced by crossing from one type of land cover to another. 4. The LiDAR data for each flight line was trimmed in batch for the removal of the overlap areas between flight lines. The data was checked against a control network to ensure that vertical requirements were maintained. Conversion to the client-specified datum and projections were then completed. The LiDAR flight line data sets were then segmented into adjoining tiles for batch processing and data management. 5. The initial batch-processing run removed 95% of points falling on vegetation. The algorithm also removed the points that fell on the edge of hard features such as structures, elevated roadways and bridges. 6. The operator interactively processed the data using LiDAR editing tools. During this final phase the operator generated a TIN based on a desired thematic layer to evaluate the automated classification performed in step 5. This allowed the operator to quickly re-classify points from one layer to another and recreate the TIN surface to see the effects of edits. Geo-referenced images were toggled on or off to aid the operator in identifying problem areas. The data was also examined with an automated profiling tool to aid the operator in the reclassification. 7. The point cloud data were delivered in LAS format. 10 - points in wetlands and ditches, 9 - points in water, 2 - ground points, and 1 - all other.
• 2008-01-25 00:00:00 - The NOAA Office for Coastal Management (OCM) received the files in LAS format. The files contained Lidar elevation measurements. The data was in Florida State Plane Projection and NAVD88 vertical datum. OCM performed the following processing to the data to make it available within the Digital Coast Data Access Viewer (DAV): 1. The data were converted from Florida State Plane West coordinates to geographic coordinates. 2. The data were converted from NAVD88 (orthometric) heights to GRS80 (ellipsoid) heights using Geoid 03. 3. The LAS data were sorted by latitude and the headers were updated.

This data can be obtained on-line at the following URL: https://coast.noaa.gov/dataviewer;