Woolpert 20170909 2017 NCTCOG Program; Lidar Project Level project level data TASK NAME: 2017 NCTCOG Program Lidar Data Acquisition and Processing Production Task Woolpert Order No. 75926 CONTRACTOR: Woolpert, Inc. This data set is comprised of lidar point cloud data, raster DEM, raster DSM, classified XYZ, hydrologic 3-d breaklines, raster intensity, survey control, project tile index, and project data extent. The North Central Texas Council of Government (NCTCOG) program is a five year contract to perform Photogrammetric, Surveying, and GIS services. The NCTCOG region includes 16 counties consisting of Dallas, Tarrant, Collin, Denton, Rockwall, Kaufman, Wise, Johnson, Hood, Erath, Hunt, Navarro, Ellis, Somervell, Palo Pinto, and Parker, which cover approximately 12,800 square miles. On a yearly basis, NCTCOG coordinates with local public agencies to determine the need for geospatial services. Based on participant interest the project area and project deliverables will be defined each year by NCTCOG and its participants. The lidar data will be acquired and processed under the requirements identified in this task order. Lidar data is a remotely sensed high resolution elevation data collected by an airborne platform. The lidar sensor uses a combination of laser range finding, GPS positioning, and inertial measurement technologies. The lidar systems collect data point clouds that are used to produce highly detailed Digital Elevation Models (DEMs) of the earth's terrain, man-made structures, and vegetation. The task required the LiDAR data to be collected at a nominal pulse spacing (NPS) of 0.5 meters. The final products include classified LAS, two (2) feet pixel raster DEMs of the bare-earth surface in ERDAS IMG Format, two (2) feet pixel raster DSMs in ERDAS IMG Format and 8-bit intensity images. Each LAS file contains lidar point information, which has been calibrated, controlled, and classified. Additional deliverables include hydrologic breakline data, control data, tile index, lidar processing and survey reports in PDF format, FGDC metadata files for each data deliverable in .xml format, classified XYZ, LAS swath data and flightline shapefiles. Ground conditions: Water at normal levels; no unusual inundation; no snow; leaf off. •There is one tile (e23317540a) that is barely inside boundary but no lidar points are located in the intersect area and was also too small to produce any pixels for raster deliverables** that were masked. ** The exception to this are the intensity images. Due to null values being erroneously introduced during the masking of the intensity images, it was decided not to mask these rasters. Since they were not masked, there is an intensity image for e23317540a. •Therefore the final counts for the tiled deliverable are as such: DEM = 7,247 DSM = 7,247 Intensity Images = 7,248** Tilescls = 7,247 TiledXYZ = 7,247 The purpose of this project is to provide orthoimagery, LiDAR, and contour services for the 2017 project. NCTCOG 2017 Program Specifications Leica ALS70 4 0.5 4 0.5 4 Varies 150 50 47 230.5 5 5 1064 1 0.22 1442 30 NAD1983 Texas Stateplane North Central Zone Feet GEOID09 0.910 N/A N/A 0.374 55 1.2 1 Geometrically unreliable points were identified using a combination of automated and manual techniques and subsequently classified as swath overlap and or noise. swath overlap points were identified in these files by adding 16 to the standard classication values 8 1 default/unclassified 2 Bare-earth 3 Low vegetation 4 Medium vegetation 5 High vegetation 6 Building 7 All noise 9 Water 17 Overlap default/unclassified 18 Overlap ground 20170121 20170207 20170208 20170209 20170210 ground condition Complete As needed -97.646519 -96.301270 33.366059 32.261165 None Lidar Project Level None United States Texas Some restrictions apply. Ownership of the data products resides with NCTCOG. Use of NCTCOG Products. The Entity’s Authorized Users may Use the NCTCOG data product in the Licensed Operating Environment for any use that furthers the Entity’s internal operations or in furtherance of the Entity’s mission. Use of Generated Output or Other Data. Except as stated, the Entity will own all original works of authorship it may independently create. Digital output from the Entity’s Use of the NCTCOG Data Product may be resized as desired and printed on black and white, color printers, or map plotters. Such printed hardcopies may be distributed to the Entity’s officers, employees, citizens, contractors, or other persons in the regular course of business for their internal use or in connection with an actual transaction. Such printed output may be further copied, photographed, or reproduced digitally on the Internet. The Entity may charge a fee for such hardcopy printouts that exceed the actual direct cost of production. Without the prior written consent of NCTCOG, the Entity may not otherwise provide copied, digitized, reproduced, transmitted or disseminated, in whole or in part, any of the original digital data product in any form. Woolpert mailing and physical address
4454 Idea Center Blvd
Dayton OH 45430 USA (937) 461-5660 (937) 461-0743 8:00 a.m. to 5:00 p.m. Eastern Standard Time All formatted data cover the entire area specified for this project and are validated using a combination of commercial lidar processing software, GIS software, and proprietary programs to ensure proper formatting and loading prior to delivery. The lidar data is visually inspected for completeness to ensure that are no void areas or missing data. Produced to meet 0.910 US Feet horizontal accuracy at 95 percent confidence level. LAS Swath Fundamental Vertical Accuracy (FVA) Tested 0.374 Survey Feet fundamental vertical accuracy at a 95 percent confidence level, derived according to NSSDA, in open terrain using 0.191 Survey Feet (RMSEz) x 1.96000 as defined by the National Standards for Spatial Data Accuracy (NSSDA); assessed and reported using National Digital Elevation Program (NDEP)/ASPRS Guidelines. Woolpert 20170909 Lidar acquisition Dayton, OH Woolpert Geospatial Services Lidar dataset 20170121 ground condition 2017 NCTCOG Program Lidar This data set is the project specified acquired point cloud data. Woolpert 20170906 Lidar deliverable processing Dayton, OH Woolpert Geospatial Services Lidar dataset 20170121 ground condition 2017 NCTCOG Program This data set is the project specified lidar deliverables. Woolpert 20170906 Hydrologic breakline deliverable processing Dayton, OH Woolpert Geospatial Services 3-d breakline dataset 20170121 ground condition 2017 NCTCOG Program Lidar This data set is the project specified hydrologic breakline deliverable. Woolpert 20170906 Tile index and data extent Dayton, OH Woolpert Geospatial Services vector dataset 20170121 ground condition 2017 NCTCOG Program Lidar This data set is the project specified tile index and data extent. Using one Leica ALS70 (lidar) system, high density data, at a nominal pulse spacing (NPS) of 0.5 meters, were collected for this task order. Leica Specs- AGL = Varies - Aircraft Speed = 150 Knots, Field of View (Full) = 50 degrees, Pulse Rate = 230.5 kHz, Scan Rate = 47 Hz, with an average side lap of 30%. Multiple returns were recorded for each laser pulse along with an intensity value for each return. Eleven (11) missions were flown between January 21, 2017 and February 10, 2017. Four (4) Global Navigation Satellite System (GNSS) Base Stations were used in support of the lidar data acquisition. Specific information regarding latitude, longitude, and ellipsoid height to the L1 phase center is included in the lidar processing report. The geoid used to reduce satellite derived elevations to orthometric heights was GEOID09. Data for the task order is referenced to the North American Datum 1983 (NAD83), Texas State Plane Coordinate System, North Central Zone, and expressed in U.S. Survey Feet. The vertical datum used for this survey will be North American Vertical Datum 1988 (NAVD88). Once the data acquisition and GPS processing phases are complete, the lidar data was processed immediately to verify the coverage had no voids. The GPS and IMU data was post processed using differential and Kalman filter algorithms to derive a best estimate of trajectory. The quality of the solution was verified to be consistent with the accuracy requirements of the project. The SBET was used to reduce the lidar slant range measurements to a raw reflective surface for each flight line. The coverage was classified to extract a bare earth digital elevation model (DEM) and separate last returns. The ALS70 calibration and system performance is verified on a periodic basis using calibration range. The calibration range consists of a large building and runway. The edges of the building and control points along the runway have been located using conventional survey methods. Inertial measurement unit (IMU) misalignment angles and horizontal accuracy are calculated by comparing the position of the building edges between opposing flight lines. The scanner scale factor and vertical accuracy is calculated through comparison of lidar data against control points along the runway. Field calibration is performed on all flight lines to refine the IMU misalignment angles. IMU misalignment angles are calculated from the relative displacement of features within the overlap region of adjacent (and opposing) flight lines. The raw lidar data is reduced using the refined misalignment angles. 2017 NCTCOG Program Lidar Acquisition 20170121 Woolpert, Inc. Geospatial Services mailing and physical address
4454 Idea Center Blvd.
Dayton OH 45430 USA (937) 461-5660 (937) 461-0743 8:00 a.m. to 5:00 p.m. Eastern Time The individual flight lines were inspected to ensure the systematic and residual errors have been identified and removed. Then, the flight lines were compared to adjacent flight lines for any mismatches to obtain a homogenous coverage throughout the project area. The point cloud underwent a classification process to determine bare-earth points and non-ground points utilizing "first and only" as well as "last of many" lidar returns. This process determined Default (Class 1), Ground (Class 2), Low Vegetation (Class 3), Medium Vegetation (Class 4), High Vegetation (Class 5), Building (Class 6), Noise (Class 7), Water (Class 9), Overlap Default (Class 17) and Overlap Ground (Class 18). The bare-earth (Class 2 - Ground) lidar points underwent a manual QA/QC step to verify the quality of the DEM as well as a peer-based QC review. This included a review of the DEM surface to remove artifacts and ensure topographic quality. Classification of water (class 9) was completed via the use of the hydrologic breaklines collected for the hydro-flattening phase. The overlap classes were determined by first identifying the overlapping areas and reclassifying the LAS data by offset from a corridor. This allows the returns located on the edge of the swath to be removed from the bare earth coverage in an effort to produce a more uniform data density. The returns determined to be overlap are then further classified to produce overlap default (class 17) and overlap ground (class 18). The surveyed ground control points are used to make vertical adjustments to the data set and to perform the accuracy checks and statistical analysis of the lidar dataset. Supervisory QC monitoring of work in progress and completed editing ensured consistency of classification character and adherence to project requirements across the entire project area. The resulting deliverables for this task order consist of classified LAS file in LAS 1.2 format, Raw Swath LAS files in LAS 1.2 format, two (2) feet pixel size DEM files in ERDAS IMG format, two (2) feet pixel raster DSMs in ERDAS IMG Format, two (2) feet pixel size 8-bit Intensity files in GeoTIFF format, classified XYZ and Hydrologic Breakline data in ESRI GDB file format. 2017 NCTCOG Program Lidar Deliverable Processing 20170121 Woolpert, Inc. Geospatial Services mailing and physical address
4454 Idea Center Blvd.
Dayton OH 45430 USA (937) 461-5660 (937) 461-0743 8:00 a.m. to 5:00 p.m. Eastern Time The compilation procedure included use of lidar intensity, bare earth surface model, point cloud data, and open source imagery in an effort to manually compile hydrologic features in a 2-d environment. Following the compilation phase, a separate process was used to adjust the breakline data to best match the water level at the time of the lidar collection. Any ponds and/or lakes were adjusted to be at or just below the bank and to be at a constant elevation. Any streams were adjusted to be at or just below the bank and to be monotonic. Manual QAQC and peer-based QC review was performed on all delineated data to ensure horizontal placement quality and on all adjusted data to ensure vertical placement quality. The final hydrologic breakline product was delivered in ESRI shape file format and was also used in the processing of the DEM deliverable. 2017 NCTCOG Program Lidar Hydrologic Breakline Deliverable Processing 20170121 Woolpert, Inc. Geospatial Services mailing and physical address
4454 Idea Center Blvd.
Dayton OH 45430 USA (937) 461-5660 (937) 461-0743 8:00 a.m. to 5:00 p.m. Eastern Time Tile Size: 3,000ft x 2,000ft. The tile file name was provided by NCTCOG.Project data extent was provided by NCTCOG and subsequently buffered by 500ft and provided in shape file format. Project deliverables were clipped to the 500ft data extent. Intensity tifs were not clipped. 2017 NCTCOG Program 20170121 Woolpert, Inc. Geospatial Services mailing and physical address
4454 Idea Center Blvd.
Dayton OH 45430 USA (937) 461-5660 (937) 461-0743 8:00 a.m. to 5:00 p.m. Eastern Time Point NAD 1983 StatePlane Texas North Central FIPS 4202 Feet 32.13333333333333 33.96666666666667 -98.5 31.66666666666667 1968500.0 6561666.666666666 coordinate pair 0.01 0.01 foot_us D North American 1983 GRS 1980 6378137.0 298.257222101 North American Vertical Datum of 1988(GEOID09) 0.01 foot_us Explicit elevation coordinate included with horizontal coordinates North Central Texas Council of Governments mailing and physical address
616 Six Flags Dr.
Arlington TX 76011 USA (817) 695-9156 Unknown 8:00 a.m. to 5:00 p.m. Central Time The information contained in these data is dynamic and may change over time. The data are not better than the original sources from which they were derived. It is the responsibility of the data user to use the data appropriately and within the limitations of the data for which it was requested and prepared, in general, and these data in particular. The related graphics are intended to aid the data user in acquiring relevant data. It is not appropriate to use the related graphics as data. Woolpert gives no warranty, expressed or implied, as to the accuracy, reliability, or completeness of these data. It is strongly recommended that these data are directly acquired from a Woolpert server, and not indirectly through other sources which may have changed the data in some way. Although these data have been processed successfully upon Woolpert’s computer system, no warranty, expressed or implied, is made regarding the utility of the data on another system, or for general or scientific purposes; nor shall the act of distribution constitute any such warranty. This disclaimer applies both to individual use of the data and aggregate use with other data. 20170906 Woolpert mailing and physical address
4454 Idea Center Blvd.
Dayton OH 45430 USA (937) 461-5660 (937) 461-0743 8:00 a.m. to 5:00 p.m. Eastern Time FGDC Content Standards for Digital Geospatial Metadata FGDC-STD-001-1998 local time