gov.noaa.nmfs.inport:64565 eng UTF8 dataset Elevation National Geodetic Survey resourceProvider NOAA Office for Coastal Management (843) 740-1202 2234 South Hobson Ave Charleston SC 29405-2413 coastal.info@noaa.gov https://coast.noaa.gov WWW:LINK-1.0-http--link NOAA Office for Coastal Management Website NOAA Office for Coastal Management Home Page information pointOfContact 2026-03-04T19:17:17 ISO 19115-2 Geographic Information - Metadata Part 2 Extensions for imagery and gridded data ISO 19115-2:2009(E) EPSG::6347 2018-2019 NOAA NGS Topobathy Lidar DEM: Trappe to Toddville, MD 2021 publication NOAA/NMFS/EDM 64565 https://www.fisheries.noaa.gov/inport/item/64565 WWW:LINK-1.0-http--link Full Metadata Record View the complete metadata record on InPort for more information about this dataset. information National Geodetic Survey 1315 East-West Hwy Silver Spring MD 20910 https://geodesy.noaa.gov/ WWW:LINK-1.0-http--link National Geodetic Survey Website Website listed for National Geodetic Survey information originator https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid18/9298/supplemental/NOAA_Chesapeake_Bay_Option_1_Lidar_and_Shoreline_Mapping_Report_v02.pdf WWW:LINK-1.0-http--link lidar report Link to lidar report download https://coast.noaa.gov/dataviewer/ WWW:LINK-1.0-http--link NOAA's Office for Coastal Management (OCM) Data Access Viewer (DAV) The Data Access Viewer (DAV) allows a user to search for and download elevation, imagery, and land cover data for the coastal U.S. and its territories. The data, hosted by the NOAA Office for Coastal Management, can be customized and requested for free download through a checkout interface. An email provides a link to the customized data, while the original data set is available through a link within the viewer. download The NOAA Chesapeake Bay MD1804 Option 1 East 4 Topobathymetric lidar data were collected by NV5 Geospatial (NV5) using Riegl VQ-880-G, VQ-880-GII, and VQ-880-GH systems. The NOAA Chesapeake Bay MD1804 Option 1 East 4 acquisition spanned from 20181107-20190417 in 14 missions. The NOAA Chesapeake Bay MD1804 Option 1 East 4 dataset includes topobathymetric data in LAS format 1.4, point data record format 6, with the following classifications in accordance with project specifications and the American Society for Photogrammetry and Remote Sensing (ASPRS) classification standards: 1 - unclassified 2 - ground 7 - noise 40 - bathymetric bottom or submerged topography 43 - submerged feature 45 - water column 46 - overlap bathymetric bottom 71 - adjacent lift unclassified 72 - adjacent lift ground 85 - adjacent lift water column 1 Overlap - edge clip This data set also includes lidar intensity values, number of returns, return number, time, and scan angle. The 100 meter buffered NOAA Chesapeake Bay MD1804 Option 1 East 4 project area covers approximately 563.829 square kilometers of an area encompassing a portion of the Chesapeake Bay and the nearby census designated places of Taylors Island, Cambridge, Madison, Woolford, and Algonquin, Maryland. LAS files were compiled in 500 m x 500 m tiles. The final classified lidar data were then transformed from ellipsoid to geoidal height (Geoid12b) and used to create 36 - 5,000 m x 5,000 m topobathymetric DEMs in GeoTIFF format with 1m pixel resolution. This lidar data was required by National Oceanic and Atmospheric Administration (NOAA), the National Geodetic Survey (NGS), Remote Sensing Division Coastal Mapping Program (CMP) to enable accurate and consistent measurement of the national shoreline. The CMP works to provide a regularly updated and consistent national shoreline to define America's marine territorial limits and manage coastal resources. National Oceanic and Atmospheric Administration (NOAA), National Geodetic Survey (NGS), Remote Sensing Division (RSD), Coastal Mapping Program (CMP) completed NOAA Office for Coastal Management (843) 740-1202 2234 South Hobson Ave Charleston SC 29405-2413 coastal.info@noaa.gov https://coast.noaa.gov WWW:LINK-1.0-http--link NOAA Office for Coastal Management Website NOAA Office for Coastal Management Home Page information custodian notPlanned https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid18/9298/supplemental/extent_ngs_topobath_trappeMD_m9298.kmz This graphic displays the footprint for this lidar data set. KML EARTH SCIENCE > LAND SURFACE > TOPOGRAPHY > TERRAIN ELEVATION EARTH SCIENCE > OCEANS > BATHYMETRY/SEAFLOOR TOPOGRAPHY > BATHYMETRY > COASTAL BATHYMETRY EARTH SCIENCE > OCEANS > COASTAL PROCESSES > COASTAL ELEVATION theme Global Change Master Directory (GCMD) Science Keywords 17.0 CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA VERTICAL LOCATION > LAND SURFACE VERTICAL LOCATION > SEA FLOOR place Global Change Master Directory (GCMD) Location Keywords 20.8 LIDAR > Light Detection and Ranging instrument Global Change Master Directory (GCMD) Instrument Keywords 17.2 Airplane > Airplane platform Global Change Master Directory (GCMD) Platform Keywords 17.2 DEM beach erosion theme DOC/NOAA/NOS/NGS > National Geodetic Survey, National Ocean Service, NOAA, U.S. Department of Commerce dataCentre Global Change Master Directory (GCMD) Data Center Keywords 2017-04-24 publication 8.5 Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA) https://forum.earthdata.nasa.gov/app.php/tag/GCMD%2BKeywords GCMD Keyword Forum Page Global Change Master Directory (GCMD). 2025. GCMD Keywords, Version 22. Greenbelt, MD: Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA). URL (GCMD Keyword Forum Page): https://forum.earthdata.nasa.gov/app.php/tag/GCMD+Keywords information custodian NGS Lidar project InPort otherRestrictions Cite As: National Geodetic Survey, [Date of Access]: 2018-2019 NOAA NGS Topobathy Lidar DEM: Trappe to Toddville, MD [Data Date Range], https://www.fisheries.noaa.gov/inport/item/64565. NOAA provides no warranty, nor accepts any liability occurring from any incomplete, incorrect, or misleading data, or from any incorrect, incomplete, or misleading use of the data. It is the responsibility of the user to determine whether or not the data is suitable for the intended purpose. otherRestrictions Access Constraints: None otherRestrictions Use Constraints: 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. otherRestrictions Distribution Liability: Any conclusions drawn from the analysis of this information are not the responsibility of NOAA, the Office for Coastal Management or its partners unclassified NOAA Data Management Plan (DMP) NOAA/NMFS/EDM 64565 https://www.fisheries.noaa.gov/inportserve/waf/noaa/nos/ngs/dmp/pdf/64565.pdf WWW:LINK-1.0-http--link NOAA Data Management Plan (DMP) NOAA Data Management Plan for this record on InPort. information crossReference vector eng; US elevation OS Independent -76.379131 -76.034717 38.309203 38.659511 | Currentness: Ground Condition 2018-11-07 2019-04-17 The NOAA Chesapeake Bay MD1804 Option 1 East 4 data includes all lidar returns. An automated grounding classification algorithm was used to determine bare earth and submerged topography point classification. The automated grounding was followed with manual editing. Depth values were adjusted per sensor to NOAA provided ground truth data. Classes 2 (ground), 40 (submerged topography), and 43 (submerged feature) were used to create the final DEMs. The full workflow used for this project will be documented in the NOAA Chesapeake Bay MD1804 Option 1 East 4 Topobathymetric lidar final report, to be provided upon project completion. Zip Zip LAS/LAZ - LASer Zip NOAA Office for Coastal Management (843) 740-1202 2234 South Hobson Ave Charleston SC 29405-2413 coastal.info@noaa.gov https://coast.noaa.gov WWW:LINK-1.0-http--link NOAA Office for Coastal Management Website NOAA Office for Coastal Management Home Page information distributor https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=9299 WWW:LINK-1.0-http--link Customized Download Create custom data files by choosing data area, product type, map projection, file format, datum, etc. A new metadata will be produced to reflect your request using this record as a base. Change to an orthometric vertical datum is one of the many options. download https://noaa-nos-coastal-lidar-pds.s3.us-east-1.amazonaws.com/dem/NGS_TrappeToToddville_MD_Topobathy_DEM_2019_9299/ WWW:LINK-1.0-http--link Bulk Download Bulk download of data files in LAZ format, geographic coordinates, orthometric heights. Note that the vertical datum (hence elevations) of the files here are different than described in this document. They will be in an orthometric datum. download dataset Horizontal Positional Accuracy Lidar horizontal accuracy is a function of Global Navigation Satellite System (GNSS) derived positional error, flying altitude, and INS derived attitude error. The obtained RMSEr value is multiplied by a conversion factor of 1.7308 to yield the horizontal component of the National Standards for Spatial Data Accuracy (NSSDA) reporting standard where a theoretical point will fall within the obtained radius 95 percent of the time (ACCr). Based on a flying altitude of 400 meters, an IMU error of 0.005 decimal degrees, and a GNSS positional error of 0.125 meters, the RMSEr value for The NOAA Chesapeake Bay MD1804 Option 1 East 4 project area is 0.139 meters, with a ACCr of 0.24 meters at the 95% confidence level. The project specification requires horizontal positions to be accurate to 1.0m(RMSE). Vertical Positional Accuracy Absolute accuracy was assessed using both Non-Vegetated Vertical Accuracy (NVA) and Vegetated Vertical Accuracy (VVA) survey methods. Survey checkpoints were evenly distributed as feasible throughout the project area. NVA compares known ground check point data that were withheld from the calibration and post-processing of the lidar point cloud to the derived gridded bare earth DEM. NVA is a measure of the accuracy of lidar point data in open areas with level slope (less than 20 degrees) where the lidar system has a high probability of measuring the ground surface and is evaluated at the 95% confidence interval (1.96*RMSE). In the NOAA Chesapeake Bay MD1804 Option 1 East 4 data extent, 15 survey checkpoints were used to assess the non-vegetated vertical accuracy. Project specifications require NVA meet 0.196 m accuracy at the 95% confidence interval. Ground check points located in land cover categories other than bare earth, urban, or submerged topography were used to compute the Vegetated Vertical Accuracy (VVA). In the NOAA Chesapeake Bay MD1804 Option 1 East 4 data extent, 7 survey checkpoints were used to assess the vegetated vertical accuracy. Project specifications require VVA meet 0.36 m based on the 95th percentile tested against the derived bare earth DEM. Submerged topography points were tested separately. In the NOAA Chesapeake Bay MD1804 Option 1 East 4 data extent, 107 survey checkpoints were used to assess the submerged topography accuracy. Project specifications require submerged topography shall meet a vertical RMSE of QL2b specified in the Draft National Coastal Mapping strategy 1.0 which is equivalent to 0.30 m RMSE at a depth of 1 m. Please refer to the NOAA Chesapeake Bay MD1804 Option 1 East 4 Topobathymetric lidar final data report for final accuracies, to be provided upon project completion. The NOAA Chesapeake Bay MD1804 Option 1 East 4 dataset Non-Vegetated Vertical Accuracy tested 0.067 m vertical accuracy at 95% confidence level against the derived bare earth DEM in open terrain using 15 ground check points, based on RMSEz (0.034 m) x 1.9600. The NOAA Chesapeake Bay MD1804 Option 1 East 4 dataset Vegetated Vertical Accuracy tested 0.206 m vertical accuracy at the 95th percentile against the derived bare earth DEM using 7 landclass points. The NOAA Chesapeake Bay MD1804 Option 1 East 4 dataset tested 0.084 m vertical accuracy at 95% confidence level against the derived topobathymetric bare earth DEM using 107 submerged check points, based on RMSEz (0.043 m) x 1.9600. Submerged topography checkpoints usually occur in depths up to 1m. Completeness Report Data covers the project boundary. Conceptual Consistency Not applicable Data for the NOAA Chesapeake Bay MD1804 Option 1 East 4 Topobathymetric lidar project area was acquired by NV5 Geospatial (NV5) using Riegl VQ-880-G, VQ-880-GII, and VQ-880-GH Topobathymetric lidar systems. All derived DEM data is referenced to: Horizontal Datum-NAD83(2011) epoch: 2010.00 Projection-UTM Zone 18N Horizontal Units-meters Vertical Datum-NAVD88 (Geoid12b) Vertical Units-meters The NOAA Chesapeake Bay MD1804 Option 1 East 4 dataset encompasses 36 5000m x 5000m tiles in an area encompassing a portion of the Chesapeake Bay and the nearby census designated places of Taylors Island, Cambridge, Madison, Woolford, and Algonquin, Maryland. Lidar data were acquired with VQ-880-G, VQ-880-GII, and VQ-880-GH Riegl sensors. The collected lidar data were immediately processed in the field by NV5 to a level that will allow QA\QC measures to determine if the sensor is functioning properly and assess the coverage of submerged topography. An initial SBET was created in POSPAC MMS 8.3 SP3 and loaded into RiProcess which applies pre-calibrated angular misalignment corrections of scanner position to extract the raw point cloud into geo-referenced LAS files. These files were inspected for sensor malfunctions and then passed through automated raster generation using LAStools to develop an initial assessment of bathymetric coverage. NV5 reviewed all acquired flight lines to ensure complete coverage and positional accuracy of the laser points. These rasters were also used to create an initial product in Quick Look Coverage Maps. These Quick Look files are not fully processed data or final products but provide rapid assessment of approximate coverage and depth penetration. NV5 resolved kinematic corrections for aircraft position data using aircraft GNSS and Applanix's proprietary PP-RTX solution. When PP-RTX was not used NV5 conducted static Global Navigation Satellite System (GNSS) ground surveys (1 Hz recording frequency) using base stations over known monument locations during flights. After the airborne survey, static GPS data were triangulated with nearby Continuously Operating Reference Stations (CORS) using the Online Positioning User Service (OPUS) for precise positioning. Multiple independent sessions over the same base station were performed to confirm antenna height measurements and to refine position accuracy. This data was used to correct the continuous on board measurements of the aircraft position recorded throughout the flight. A final smoothed best estimate trajectory (SBET) was developed that blends post-processed aircraft position with attitude data. Using the SBETs, sensor head position and attitude were then calculated throughout the survey. Trimble Business Center v.3.90, Blue Marble Geographic Calculator 2019, and PosPac MMS 8.3 SP3 were used for these processes. Following final SBET creation, NV5 used RiProcess 1.8.5 to calculate laser point positioning by associating SBET positions to each laser point return time, scan angle, and intensity. Terra 19 and LasTools were used to classify water surface and create a water surface model. They are created for single swaths to ensure temporal differences and wave or water surface height variations between flight lines do not impact the refraction of the bathymetric data. These models are used in NV5's LasMonkey refraction tool to determine the accurate positioning of bathymetric points. All lidar data below water surface models were classified as water column to be refracted. Light travels at different speeds in air versus water and its direction of travel or angle is changed or refracted when entering the water column. The refraction tool corrects for this difference by adjusting the depth (distance traveled) and horizontal positioning (change of angle/direction) of the lidar data. Using raster-based QC methods, the output data is verified to ensure the refraction tool functioned properly. 2020-12-17T00:00:00 NGS Communications and Outreach Branch (301) 713-3242 ngs.infocenter@noaa.gov processor Once all data was refracted by flight line data was exported to LAS 1.4 format and combined into 500 m x 500 m tiles. Data were then further calibrated using TerraMatch. NV5 used custom algorithms in TerraScan to classify the initial ground/submerged topography surface points. Relative accuracy of overlapping swaths was compared and verified through the use Delta-Z (DZ) orthos created using NV5's Las Product Creator. Absolute vertical accuracy of the calibrated data was assessed using ground survey data and complete coverage was again verified. Post automated classification NV5 then performed manual editing to review all classification and improve the final Topobathymetric surface. NV5's LasMonkey was used to update LAS header information, including all projection and coordinate reference system information. The final lidar data are in LAS format 1.4 and point data record format 6. The final classification scheme is as follows: 1 - unclassified 2 - ground 7 - noise 40 - bathymetric bottom or submerged topography 43 - submerged feature 45 - water column 46 - overlap bathymetric bottom 71 - adjacent lift unclassified 72 - adjacent lift ground 85 - adjacent lift water column 1 Overlap - edge clip 2020-12-17T00:00:00 NV5 transformed the final lidar data from ellipsoid heights to orthometric heights referenced to NAVD88, Geoid 12b to create the final topobathymetric void clipped DEMs. The topobathymetric bare earth DEMs were output at 1 meter resolution in GeoTIFF format into 36 - 5,000 m x 5,000 m tiles. The NOAA Chesapeake Bay MD1804 Option 1 East 4 rasters are clipped to the extent of the project boundary and named according to project specifications. A bathymetric void shapefile was created to indicate areas where there was a lack of bathymetric returns. This shape was created by triangulating bathymetric bottom points with an edge length maximum of 4.56m to identify all areas greater then 9 square meters without bathymetric returns. This shapefile was used to clip and exclude interpolated elevation data from these areas in the bathymetric void clipped topobathymetric bare earth model. 2020-12-17T00:00:00 NGS Communications and Outreach Branch (301) 713-3242 ngs.infocenter@noaa.gov processor Acquisition and Processing NV5 Geospatial, Inc originator