gov.noaa.csc.maps:2006_TX_Brazoria_m95 Texas Water Development Board (TWDB) 200708 Charleston, SC NOAA's Ocean Service (NOS), Coastal Services Center (CSC) http://www.csc.noaa.gov/lidar Using a LH Systems ALS50 Light Detection And Ranging (LiDAR) system, flight lines of standard density (1.4 meter ground sample distance) data were collected over areas in Brazoria County, TX (approximately 1428 square miles). Multiple returns were recorded for each laser pulse along with an intensity value for each return. The data acquisition occurred in 6 missions between April 9, 2006, April 16, 2006, April 17, 2006, and May 11, 2006 through May 13, 2006. The data was collected by Sanborn Mapping Company, Inc. for the Texas Water Development Board (TWDB) and the Federal Emergency Management Agency (FEMA). This LIDAR operation was designed to provide a high density set of masspoints within the defined areas. The data sets are suitable for the development of contours for use in hydraulic/hydrologic model development, and for assessing environmental impacts. Typical uses for the data set include: FEMA Flood Plain Map Modernization, DFIRM map updates, watersheds and other hydro studies per FEMA specifications, county mapping projects, and flood mitigation assessment. 20060409 20060416 20060417 20060511 20060513 Publication date Complete None planned -95.874983 -95.046783 29.603391 28.818691 ISO 19115 Topic Category Elevation None Bathymetry/Topography DEM Digital elevation model Elevation Digital terrain model Surface Model Hydraulic Hydrographic Lidar Hydrologic Modeling Drainage Area Hydrology TNRIS (Texas Natural Resources Information System) None United States Texas Brazoria County None 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be aware that temporal changes may have occurred since this data set was collected and some parts of this data may no longer represent actual surface conditions.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. Ryan Mitchell Texas Natural Resources Information System (TNRIS) Mailing and physical address

1700 N. Congress Ave.

Austin Texas 78711 United States 512-463-8337 512-463-7274 lidar@tnris.state.tx.us Data collected by Sanborn Mapping Company, Inc. for the Texas Water Development Board (TWDB) and the Federal Emergency Management Agency (FEMA). Acknowledgement of TNRIS (Texas Natural Resources Information System) would be appreciated in products derived and used from this data. Sanborn Mapping Company asks to be credited in derived products. Microsoft Windows XP Version 5.1 (Build 2600) Service Pack 2; ESRI ArcCatalog 9.2.2.1350 None None FEMA LiDAR Specifications FEMA LiDAR Specifications; +/- 18 cm in open terrain Data Collection: Using a LH Systems ALS50 Light Detection And Ranging (LiDAR) system, flight lines of standard density (1.4 meter ground sample distance) data were collected over areas in Brazoria County, TX (approximately 1428 square miles). Multiple returns were recorded for each laser pulse along with an intensity value for each return. The data acquisition occurred in 6 missions between April 9, 2006, April 16, 2006, April 17, 2006, and May 11, 2006 through May 13, 2006. During the LIDAR campaign, the Sanborn field crew conducted a GPS field survey to establish final coordinates of the ground base stations for final processing of the base-remote GPS solutions. 200708 Jamie Young Sanborn Mapping LiDAR Manager Mailing and physical address

1935 Jamboree Drive

Colorado Springs Colorado 80920 United States 719-264-5602 719-264-5637 jyoung@sanborn.com Airborne GPS Processing: Airborne GPS data was differentially processed and integrated with the post processed IMU data to derive a smoothed best estimate of trajectory (SBET). The SBET was used to reduce the LiDAR slant range measurements to a raw reflective surface for each flight line. The overlap between flight lines was removed to provide a homogeneous coverage, and the coverage was classified to extract a bare earth digital elevation model (DEM). Airborne GPS is differentially processed using the GrafNAV V7.50 software by Waypoint Consulting of Calgary, Alberta, Canada. The PDOP and distance separation is as follows: IMU data is processed using the PosPac V4.2 software by Applanix Corporation of Richmond Hill, Ontario, Canada. The reflective surface is derived using the ALS Post Processor software by Leica Geosystems GIS & Mapping Division of Atlanta, Georgia. The classification and quality control (QC) of LiDAR data is carried out using TerraScan software by Terrasolid Limited of Helsinki, Finland. 200708 Jamie Young Sanborn Mapping LiDAR Manager Mailing and physical address

1935 Jamboree Drive

Colorado Springs Colorado 80920 United States 719-264-5602 719-264-5637 jyoung@sanborn.com IMU data Processing: IMU data provides information concerning roll, pitch and yaw of collection platform during collection event. IMU information allows the pulse vector to be properly placed in 3D space allowing the distance from the aircraft reference point to be properly positioned on the elevation model surface. IMU data is processed using the PosPac V4.2 software by Applanix Corporation of Richmond Hill, Ontario, Canada. 200708 Jamie Young Sanborn Mapping LiDAR Manager Mailing and physical address

1935 Jamboree Drive

Colorado Springs Colorado 80920 United States 719-264-5602 719-264-5637 jyoung@sanborn.com Reflective Surface Generation: The reflective surface is derived using the ALS Post Processor software by Leica Geosystems GIS & Mapping Division of Atlanta, Georgia. 200708 Jamie Young Sanborn Mapping LiDAR Manager Mailing and physical address

1935 Jamboree Drive

Colorado Springs Colorado 80920 United States 719-264-5602 719-264-5637 jyoung@sanborn.com LIDAR Point Classification The classification and quality control (QC) of LiDAR data is carried out using TerraScan software by Terrasolid Limited of Helsinki, Finland. 200708 Jamie Young Sanborn Mapping LiDAR Manager Mailing and physical address

1935 Jamboree Drive

Colorado Springs Colorado 80920 United States 719-264-5602 719-264-5637 jyoung@sanborn.com Output LAS Files The product output of LiDAR data is carried out using TerraScan software by Terrasolid Limited of Helsinki, Finland. LAS Binary, ascii xyz, and intensity images were created. 200708 Jamie Young Sanborn Mapping LiDAR Manager Mailing and physical address

1935 Jamboree Drive

Colorado Springs Colorado 80920 United States 719-264-5602 719-264-5637 jyoung@sanborn.com The NOAA Coastal Services Center (CSC) received the files in las format. The files contained Lidar elevation and intensity measurements. The data was in UTM projection, and NAVD88 Geoid 03 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 UTM 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. 20080813 Department of Commerce (DOC), National Oceanic and Atmospheric Administration (NOAA), National Ocean Service (NOS), Coastal Services Center (CSC) Coastal Elevation Mapping (CEM) Project Scientist Mailing and physical address

2234 South Hobson Ave.

Charleston SC 29405-2413 843-740-1200 tcm@csc.noaa.gov The NOAA National Geophysical Data Center (NGDC) received Lidar data files on external harddrive. The disk contains LiDAR data from the NOAA Coastal Services Center. The data are currently being served via Digital Coastl at http://www.csc.noaa.gov/digitalcoast/. The data can be used to re-populate the system. The data are provided on this disk in LAS format. LAS format is an industry standard for serving LiDAR data. The data are exclusively in geographic coordinates, however, the datums used vary. Most are NAD 83, however some are in ITRF. Vertical systems include both ellipsoid (ITRF and NAD 83) and NAVD 88. For NAVD 88 values, Geiod 03 is primarily used; however, data received in NAVD 88 prior to 2003 was processed using Geoid 99. 20090723 DOC/NOAA/NESDIS/NGDC > National Geophysical Data Center, NESDIS, NOAA, U.S. Department of Commerce Pamela Grothe Mailing and Physical Address

NOAA/NESDIS/NGDC E/GC1 325 Broadway

Boulder CO 80305-3328 USA (303) 497-6120 (303) 497-6958 (303) 497-6513 pamela.grothe@noaa.gov 7:30-5:00 Mountain Contact Data Center Point 0.000000001 0.000000001 Decimal degrees North American Datum of 1983 Geodetic Reference System 80 6378137.000000 298.257222 Ellipsoid 0.001 Meters Explicit elevation coordinate included with horizontal coordinates Department of Commerce (DOC), National Oceanic and Atmospheric Administration (NOAA), National Ocean Service (NOS), Coastal Services Center (CSC) Coastal Elevation Mapping (CEM) Project Scientist Mailing and physical address

2234 South Hobson Ave.

Charleston SC 29405-2413 843-740-1200 tcm@csc.noaa.gov Downloadable Data Any conclusions drawn from the analysis of this information are not the responsibility of the Coastal Services Center or its partners. This data can be obtained on-line at the following URL: http://www.csc.noaa.gov/lidar DOC/NOAA/NESDIS/NGDC > National Geophysical Data Center, NESDIS, NOAA, U.S. Department of Commerce Pamela Grothe Mailing and Physical Address

NOAA/NESDIS/NGDC E/GC1 325 Broadway

Boulder CO 80305-3328 USA (303) 497-6120 (303) 497-6958 (303) 497-6513 pamela.grothe@noaa.gov 7:30-5:00 Mountain Contact Data Center Disclaimer While every effort has been made to ensure that these data are accurate and reliable within the limits of the current state of the art, NOAA cannot assume liability for any damages caused by any errors or omissions in the data, nor as a result of the failure of the data to function on a particular system. NOAA makes no warranty, expressed or implied, nor does the fact of distribution constitute such a warranty. The National Geophysical Data Center serves as the archive for this LIDAR data. NGDC should only be contacted for this data if it cannot be obtained from NOAA Coastal Services Center. 20111119 20111119 20121119 Department of Commerce (DOC), National Oceanic and Atmospheric Administration (NOAA), National Ocean Service (NOS), Coastal Services Center (CSC) Coastal Elevation Mapping (CEM) Project Scientist Mailing and physical address

2234 South Hobson Ave.

Charleston SC 29405-2413 843-740-1200 tcm@csc.noaa.gov FGDC Content Standards for Digital Geospatial Metadata FGDC-STD-001-1998