U.S. Geological Survey 20260413 Raster Digital Data Set Denver, CO U.S. Geological Survey https://www.usgs.gov/3d-elevation-program https://apps.nationalmap.gov/downloader/ U.S. Geological Survey Denver, CO U.S. Geological Survey https://doi.org/10.5066/P13LJKFS 2026 To advance the U.S. Geological Survey 3D National Topography Model (3DNTM) including the next generation of the 3D Elevation Program (3DEP) and the 3D Hydrography Program (3DHP), the USGS researched and created a Seamless 1-meter resolution (S1M) Digital Elevation Model (DEM) for the conterminous United States. This dataset is a result of a joint project between the National Geospatial Technical Operations Center (NGTOC) and the Earth Resources Observation and Science Center (EROS) of the USGS National Geospatial Directorate (NGD). Scientists and resource managers can use the S1M data for global change research, hydrologic modeling, resource monitoring, mapping, visualization, and many other applications. A S1M DEM requires merging multiple lidar projects in which the lidar sensor, bare-earth DEM generation methodology, source resolution, datums/projection, unit of measure, and geoid (mean sea level model) can vary between projects. This tile of the Seamless 1-m DEM was created from the best available 3DEP Original Product Resolution source DEMs from one or several intersecting 3DEP data collection projects. Spatially referenced metadata are contained within an open-source GeoPackage that stores footprints for each of the input source DEMs along with source data characteristics. The source DEMs were processed to align vertically to North American Vertical Datum of 1988 (EPSG: 5703) updated to the current GEOID18 model and projected horizontally to North American Datum of 1983 (2011) USA Contiguous Albers Equal Area Conic projection (EPSG: 6350). Horizontal units and elevation values are in meters. Large data voids wider than 10 meters in the tile were backfilled with 1/9 arc-second or 1/3 arc-second DEMs in the 3DEP data repository while small data voids were interpolated across using bilinear interpolation. For tiles containing more than one 3DEP project or with large data voids, up to three blending routines were used: a simple blend, narrow blend, or a backfill blend. The spatial metadata GeoPackage contains information on where backfilling, void interpolation, and blending occurs within the tile. The tile spatial extent is 10 km x 10 km. The S1M DEM is available in a Cloud Optimized Georeferenced Tagged Image File Format (GeoTIFF). The S1M DEM has floating point numeric values and a spatial resolution of one meter. NoData values (areas where data is incomplete due to lack of full data coverage) are represented with the numeric value of -999999. To support the USGS 3D National Topography Model (3DNTM), which includes the next generation of 3DEP and the 3D Hydrography Program, USGS is producing a Seamless 1-m DEM (S1M). The S1M DEM data provide seamless integrated elevation products aligned both vertically and horizontally to a common reference system for the conterminous United States. This data can be critical to various science application studies such as flood risk management, 2D/3D hydrologic modeling, river geomorphology applications, sediment-transport, aquatic habitat restoration, resource management, mapping, visualization, and for analyses of the potential impacts of various climate change scenarios on dynamically changing landscapes The data obtained through ScienceBase at https://doi.org/10.5066/P13LJKFS are considered the "best available" data from the USGS. For questions on distribution, please refer to the Distribution Section, Contact Information. For processing, please refer to the Data Quality Section, Processing Step, and Contact Information.; {"inventory":"b449e48d-393f-4446-5744-47b893e5551b"} 20220409 20220430 ground condition Complete As needed -74.23591937986538 -74.09104028090329 41.49020322897 41.38286140543163 ISO 19115 Topic Category elevation geoscientificInformation Theme U.S. Geological Survey National Geospatial Directorate (NGD) National Geospatial Program (NGP) 3D National Topography Model (3DNTM) 3D Elevation Program (3DEP) 3D Hydrography Program (3DHP) 3D Elevation Program (3DEP) 3D Elevation Program 3DEP Elevation Grid Lidar Light Detection and Ranging High Resolution Topographic Surface Topography Bare Earth Hydro-Flattened Terrain Elevation Cartography DEM Digital Elevation Model Geographic Information System GIS Digital Mapping Digital Terrain Model Geodata Mapping Raster Seamless 1-m DEM S1M COG Cloud Optimized GeoTIFF Geographic Names Information System United States New York The National Map Type Thesaurus Downloadable Data The National Map Theme Thesaurus Elevation The National Map Collection Thesaurus Seamless 1-m DEM (S1M) Current Seamless 1-m DEM (S1M) 3D Elevation Program (3DEP) The National Map Product Extent Thesaurus 10000 x 10000 meter The National Map Product Format Thesaurus GeoTIFF Unless otherwise stated, all data, metadata and related materials satisfy the quality standards for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data for other purposes, nor on all computer systems, nor shall the act of distribution constitute any such warranty. Although these data have been processed successfully on a computer system at the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data for other purposes, nor on all computer systems, nor shall the act of distribution constitute any such warranty. The USGS or the U.S. Government shall not be held liable for improper or incorrect use of the data described and/or contained herein. U.S. Geological Survey - Core Science Systems mailing and physical

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Lakewood CO 80225 United States of America 1-888-392-8545 tnm_help@usgs.gov USGS National Geospatial Program: 3D Elevation Program For usability, Esri ArcGIS, Esri ArcGIS Pro, Global Mapper, QGIS, Geospatial Data Abstraction Library (GDAL), or equivalent GIS processing software and supporting operating systems are suggested for viewing the S1M DEM GeoTIFF or the spatial metadata GeoPackage. Environment as of Metadata Creation: USGS Metadata Wizard 2.0.8; Esri ArcGIS Pro 3.3.2 Service Pack N/A (Build N/A) William M. Cushing Dean J. Tyler 20240914 publication Remote Sensing vol. 16, issue 18 n/a MDPI AG ppg. 3418 https://doi.org/10.3390/rs16183418 https://prd-tnm.s3.amazonaws.com/StagedProducts/Elevation/S1M/n22e17/n2260e1790/S1M_n2260e1790_20260410.jpg Thumbnail JPG image JPEG No formal attribute accuracy tests were conducted. All S1M tiles were visually reviewed using shaded relief images at 1:5,000 scale for artifacts with a focus on blend areas between lidar projects. Data set is considered complete for the information presented, as described in the abstract. Users are advised to read the rest of the metadata record carefully for additional details. The horizontal accuracy for the integrated Seamless 1-m digital elevation model was not assessed quantitatively. All elevations are referenced to GEOID18. Seamless 1-m (S1M) Vertical Accuracy Assessment: An absolute vertical accuracy assessment was performed that differenced this S1M tile with 4 survey grade checkpoints collected by USGS contractors in the area of interest between 2013 and 2022. Compared to the validation points, the average absolute error is 0.0732 meters. An absolute vertical accuracy assessment was performed that differenced all the S1M tiles that make up the Lower Wallkill River Hydrologic Unit 10 with 52 survey grade checkpoints collected by USGS contractors in the area of interest between 2013 and 2022. Compared to the validation points, the overall vertical root mean square error (RMSE) is 0.0990 meters. The principal methodology for developing the Seamless 1-m (S1M) digital elevation model (DEM) for each 10 km x 10 km tile can be organized into three steps. Topographic digital elevation data were acquired by the USGS 3D Elevation Program using near-infrared wavelength (1064 nm) topographic lidar by areas referred to as work units. Only lidar projects that were Quality Level 2 (QL2) or better were used as the primary data source. QL2 requires a pulse density of at least two pulses per square meter and a RMSE of better than 10 cm in non-vegetated areas. The first step, “Data Preparation”, gathers the Original Product Resolution Source DEMs and metadata for the integrated terrain model. The product for the first step is a series of DEM Virtual Raster (VRT) mosaics for each lidar work unit with their associated spatial footprints and project metadata. There may be a single VRT if only one lidar project covers the entire tile. These are passed on to the second step, “Data Transformation”. The vertical and horizontal datum and projection information of all input sources must be referenced to North American Vertical Datum of 1988 (NAVD88) (EPSG: 5703) GEOID18 and North American Datum of 1983 (2011) (NAD83 (2011)) USA Contiguous Albers Equal Area Conic projection (EPSG: 6350). If source data were not in native NAVD88-GEOID18, data were transformed to the NAVD88-GEOID18 reference frame using the current National Geodetic Survey (NGS) geoid model grids and a custom EROS developed Geoid2Geoid tool. Likewise, if required, input source data were converted to the NAD83 (2011) datum and re-projected to the USA Contiguous Albers Equal Area Conic coordinate system. The third step, “Integration and Export”, encompasses the spatial assimilation of the topographic data components. To generate the final S1M DEM data, layers are prioritized for integration based on accuracy and the temporal order of collection. Data voids and overlapping project coverage are identified to assist with backfilling and blending. Large data voids, wider than 10 m, are backfilled with 1/9 arc-second or 1/3 arc-second DEMs in the 3DEP data repository while small data voids are interpolated across using bilinear interpolation. For tiles containing more than one 3DEP project or with large data voids, up to three blending routines are used: a simple blend (10 m linear), narrow blend (less than or equal to 10 m overlap between projects), or a backfill blend (50 m slope weighed linear blend). Interpolation rasters for small data voids, backfill rasters for large data voids, and blend rasters are all generated and combined in a VRT mosaic. This void fill and blend VRT is stacked on top of a VRT of all the input OPR Source DEM GeoTIFFs in priority order and exported as one GeoTIFF. The final DEM is clipped to the tile boundary and exported into a Cloud Optimized GeoTIFF with a consistent snap raster, NoData value, and compound coordinate reference system. Spatial metadata and XML metadata is also generated for the DEM. Quality assurance control checks were done for all spatial processing steps by verifying statistics and visual inspection of shaded relief images. 20260413 U.S. Geological Survey - Core Science Systems mailing and physical

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Lakewood CO 80225 United States of America 1-888-392-8545 tnm_help@usgs.gov Digital and/or Hardcopy NY_SE4County_1_A22 NY_SE4County_1_A22 Topographic Lidar USGS 3DEP 20240923 raster digital data https://prd-tnm.s3.amazonaws.com/index.html?prefix=StagedProducts/Elevation/OPR/Projects/NY_SouthEast4County_A22/NY_SE4County_1_A22 ground condition Raster Grid Cell 10000 10000 1 Albers Conical Equal Area 29.5 45.5 -96.0 23.0 0.0 0.0 row and column 1.0 1.0 meters NAD83_National_Spatial_Reference_System_2011 GRS 1980 6378137.0 298.257222101 North American Vertical Datum of 1988 0.01 meters Explicit elevation coordinate included with horizontal coordinates S1M_n2260e1790_20260410.tif Raster geospatial data file. Producer Defined Value Unique numeric values contained in each raster cell. Producer Defined -999999 Areas where data is incomplete due to lack of full data coverage or NoData. Producer defined 74.016258239746 512.33654785156 Meter 1.0 This collection of high-resolution elevation data is available in Cloud Optimized Georeferenced Tagged Image File Format (GeoTIFF). The elevation model has floating point numeric values. Areas where data is incomplete due to lack of full data coverage or NoData are represented with the numeric value of -999999. Spatially referenced metadata is contained within a GeoPackage that contains footprints with accompanying attribute fields for each of the source input areas. The data dictionary for the spatial metadata GeoPackage attributes is available at https://doi.org/10.5066/P13LJKFS https://doi.org/10.5066/P13LJKFS U.S. Geological Survey GS ScienceBase mailing address

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Denver CO 80225 United States 1-888-275-8747 sciencebase@usgs.gov Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data for other purposes, nor on all computer systems, nor shall the act of distribution constitute any such warranty. TIFF 351.4371 https://prd-tnm.s3.amazonaws.com/StagedProducts/Elevation/S1M/n22e17/n2260e1790/S1M_n2260e1790_20260410.tif None 20260420 U.S. Geological Survey - Core Science Systems mailing and physical

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Lakewood CO 80225 United States of America 1-888-392-8545 tnm_help@usgs.gov FGDC Content Standard for Digital Geospatial Metadata FGDC-STD-001-1998 https://prd-tnm.s3.amazonaws.com/index.html?prefix=StagedProducts/Elevation/metadata/NY_SouthEast4County_A22/NY_SE4County_1_A22 spatial metadata https://prd-tnm.s3.amazonaws.com/StagedProducts/Elevation/S1M/n22e17/n2260e1790/S1M_n2260e1790_20260410.gpkg