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2006 Southwest Florida Water Management District (SWFWMD) Lidar: Upper Myakka District

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.

Cite this dataset when used as a source.

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    Distribution Formats
    • LAZ
    Distributor DOC/NOAA/NOS/CSC > Coastal Services Center, National Ocean Service, National Oceanic and Atmospheric Administration, U.S. Department of Commerce
    Point of Contact Mapping and GIS Section
    Southwest Florida Water Management District
    352.796.7211
    Associated Resources
    • Lidar Final Report
    Originator
    • DOC/NOAA/NOS/CSC > Coastal Services Center, National Ocean Service, National Oceanic and Atmospheric Administration, U.S. Department of Commerce
    Originator
    • Southwest Florida Water Management District (SWFWMD)
    Publisher
    • DOC/NOAA/NOS/CSC > Coastal Services Center, National Ocean Service, National Oceanic and Atmospheric Administration, U.S. Department of Commerce
    Date(s)
    • publication: 2006-12-04
    Data Presentation Form: Digital image
    Dataset Progress Status Complete
    Data Update Frequency: As needed
    Purpose: This project was designed to provide topographic information to the Southwest Florida Water Management District to support regulatory, land management and acquisition, planning, engineering and habitat restoration projects.
    Use Limitations
    • These data depict the elevations at the time of the survey and are only accurate for that time. Users should be aware that temporal changes may have occurred since this data set was collected and some parts of this data may no longer represent actual surface conditions. Users should not use this data for critical applications without a full awareness of its limitations. Any conclusions drawn from analysis of this information are not the responsibility of NOAA or any of its partners. These data are NOT to be used for navigational purposes.
    Time Period: 2006-10-03  to  2006-10-12
    Spatial Reference System: urn:ogc:def:crs:EPSG::4269 Ellipsoid in Meters
    Spatial Bounding Box Coordinates:
    N: 27.555841
    S: 27.176931
    E: -081.879906
    W: -082.451361
    Spatial Coverage Map:
    Themes
    • Bathymetry/Topography
    • LiDAR
    • Bare Earth
    • Terrain
    • Model
    • Elevation
    • Surface
    Places
    • US
    • Florida
    • Southwest Florida
    • Manatee County
    • Upper Myakka
    Use Constraints No constraint information available
    Fees Fee information not available.
    Source Datasets
    • Upper Myakka Aerial Acquisition
      • Description of Source: Source Contribution: Aerial Acquisition. EarthData International collected ALS-50-derived LiDAR over Upper Myakka Florida with a one-meter post spacing using aircraft number N62912. The period of collection was between 3 October and 12 October 2006. The collection was performed by EarthData Aviation, using a Leica ALS-50 LiDAR system, serial number ALS039, including an inertial measuring unit (IMU) and a dual frequency GPS receiver. This project required six lifts of flight lines to be collected. The lines were flown at an average of 3000 feet above mean terrain using a pulse rate of 75,000 pulses per second. Source Type: External hard drive
      • Temporal extent used:  2006-10-03  to  2006-10-12
    • Report of GPS Survey Upper Myakka Area, FL
      • Description of Source: Source Contribution: Ground Control. EarthData International was contracted to provide mapping services in the Upper Myakka area of Florida. Aerial imagery and LiDAR data was collected for the project area. EarthData subcontracted the ground survey tasks to Kevin J. Chappell, Florida PSM License No. LS5818. The Global Positioning System (GPS) was used to establish the control network. There were a total of 41 stations occupied for this project. There were 19 new photo control stations, 11 new LIDAR control stations, 4 temporary GPS base stations, 5 existing NSRS control stations, 1 CORS station, and 1 airborne GPS base station used by the flight crew. The final network was adjusted using least squares. A free adjustment and constrained adjustment were performed. The results of the free adjustment indicate an external network accuracy of better than 3 cm in relation to NAD 1983 1999 and NAVD 1988. The results of the constrained adjustment indicate an internal network accuracy of better than 3 cm in relation to NAD 1983 1999 and NAVD 1988. Source Type: Paper
      • Temporal extent used:  2006-03-07  to  2006-04-13
    • LiDAR Land Cover Control, Report of GPS Survey
      • Description of Source: Source Contribution: LiDAR Land Cover QC Survey. EarthData International was contracted to provide mapping services in the Upper Myakka area of Florida. LiDAR data was collected for the project area. EarthData subcontracted the quality control survey tasks to WilsonMiller, Inc. The Global Positioning System (GPS) was used to establish the control network. There were a total of 93 stations occupied for this project. 64 new LiDAR land cover control stations, 4 NGS base control stations, 8 FDEP 2005 base control stations, and 9 NGS control check stations. Source Type: Paper
      • Temporal extent used:  2007-01-15  to  2007-02-12
    Lineage Statement Lineage statement not available.
    Processor
    • EarthData International
    • DOC/NOAA/NOS/CSC > Coastal Services Center, National Ocean Service, National Oceanic and Atmospheric Administration, U.S. Department of Commerce
    • DOC/NOAA/NESDIS/NGDC > National Geophysical Data Center, NESDIS, NOAA, U.S. Department of Commerce
    Processing Steps
    • 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.
    • 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.
    • The NOAA Coastal Services Center (CSC) received the files in LAS format. The files contained Lidar elevation measurements. The data was in Florida State Plane Projection and NAVD88 vertical datum. CSC performed the following processing to the data to make it available within the LDART Retrieval Tool (LDART): 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.
    • The NOAA National Geophysical Data Center (NGDC) received lidar data files via ftp transfer from the NOAA Coastal Services Center. The data are currently being served via NOAA CSC Digital Coast at http://www.csc.noaa.gov/digitalcoast/. The data can be used to re-populate the system. The data are archived in LAS or LAZ format. The LAS format is an industry standard for LiDAR data developed by the American Society of Photogrammetry and Remote Sensing (ASPRS); LAZ is a loseless compressed version of LAS developed by Martin Isenburg (http://www.laszip.org/). The data are exclusively in geographic coordinates (either NAD83 or ITRF94). The data are referenced vertically to the ellipsoid (either GRS80 or ITRF94), allowing for the ability to apply the most up to date geoid model when transforming to orthometric heights.

    Metadata Last Modified: 2013-06-11

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