Aero-Graphics, Inc. 20231117 vector data Product: Breakline data is used to hydroflatten the DEMs created for the 224853_UT_WestEast_7_B22 - West Desert South A WUID300370, Utah 2022 Lidar project. Breaklines are reviewed against lidar intensity imagery to verify completeness of capture. Geographic Extent: WUID300370 covering approximately 2,200 square miles. Dataset Description: WUID300370, 224853_UT_WestEast_7_B22 - West Desert South A, Utah 2022 Lidar project called for the Planning, Acquisition, processing and derivative products of lidar data to be collected at a nominal pulse spacing (NPS) of 0.35 meters. Project specifications are based on the U.S. Geological Survey National Geospatial Program Base Lidar Specification 2022, Revision A. The data was developed based on a horizontal projection/datum of NAD83 (2011), Universal Transverse Mercator Zone 12N, meters and vertical datum of NAVD88 (GEOID18), meters. Lidar data was delivered as processed Classified LAZ 1.4 files, formatted to 5,785 individual 1000 m x 1000 m tiles, as tiled Intensity Imagery, and as tiled bare earth DEMs and DSMs; all tiled to the same 1000 m x 1000 m schema. Ground Conditions: Lidar was collected in Summer and Fall 2022, while no snow was on the ground and rivers were at or below normal levels. In order to post process the lidar data to meet task order specifications and meet ASPRS vertical accuracy guidelines, the Aero-Graphics Team, established a total of 13 ground control points that were used to calibrate the lidar to known ground locations established throughout the WUID300370 project area. An additional 41 independent accuracy checkpoints, 24 in Bare Earth and Urban landcovers (24 NVA points), 17 in Tall Grass and Brushland/Low Trees categories (17 VVA points), were used to assess the vertical accuracy of the data. These checkpoints were not used to calibrate or post process the data. To acquire detailed surface elevation data for use in conservation planning, design, research, floodplain mapping, dam safety assessments and elevation modeling, etc. Classified LAS files are used to show the manually reviewed bare earth surface. This allows the user to create Intensity Images, Breaklines and Raster DEM. The purpose of these lidar data was to produce high accuracy 3D hydro-flattened Digital Elevation Model (DEM) with a 0.5 meter cell size. These lidar point cloud data were used to create intensity images, 3D breaklines, and hydro-flattened DEMs as necessary. USGS Contract No. G10PC01234 CONTRACTOR: Aero-Graphics, Inc. SUBCONTRACTOR: Dewberry. Lidar data were acquired and calibrated by Dewberry. All follow-on processing was completed by Dewberry. Breakline File Type = GDB Breakline Elevation Units = Meters Downhill Treatment Applied = Monotonic Type of Hydro Treatment Required = Hydro-flattened 20220624 20221031 ground condition Complete None planned -114.073747 -112.815734 39.348061 38.754951 235023.639803 342282.374195 4357000.000000 4294000.000000 None Model Breaklines Elevation Data Lidar None Utah UT Millard County No restrictions apply to these data. None. However, users should be aware that temporal changes may have occurred since this dataset was collected and that some parts of these data may no longer represent actual surface conditions. Users should not use these data for critical applications without a full awareness of its limitations. Acknowledgement of the U.S. Geological Survey would be appreciated for products derived from these data. Data covers WUID300370 specified for this project. Breaklines were collected in all inland ponds and lakes ~2 acres or greater. These features were flat and level water bodies at a single elevation for each vertex along the bank. The entire water surface edge is at or below the immediate surrounding terrain. Breaklines were collected for all streams and rivers ~100' nominal width or wider. These features are flat and level bank to bank, gradient will follow the surrounding terrain and the water surface will be at or below the surrounding terrain. Streams/river channels will break at culvert locations however not at elevated bridge locations. Breaklines were collected as polygon features depicting water bodies such as oceans, seas, gulfs, bays, inlets, salt marshes, very large lakes, ect. Includes any significant water body that is affected by tidal variations. Tidal variations over the course of collection, and between different collections, can result in discontinuities along shorelines. This is considered normal and should be retained. Variations in water surface elevation resulting from tidal variations during collection should not be removed or adjusted. Features should be captured as a dual line with one line on each bank. Each vertex placed shall maintain vertical integrity. Parallel points on opposite banks of the tidal waters must be captured at the same elevation to ensure flatness of the water feature. The entire water surface edge is at or below the immediate surrounding terrain. Donuts will exist where there are islands greater than 1 acre in size within a hydro feature. Bridge Saddle Breaklines were collected where bridge abutments were interpolated after bridge removal causing saddle artifacts. All files are inspected to ensure that they conform to the specified file naming conventions, all files load in their correct geographic position, all files conform to the project specifications for file standard and content. Hydro Flattening Breakline Processing: Class 2 (ground) lidar points was used to create a bare earth surface model. The surface model was then used to heads-up digitize 2D breaklines of inland streams and rivers with a 30-meter nominal width, and Inland Ponds and Lakes of 2 acres or greater surface area. Elevation values were assigned to all Inland Ponds and Lakes, Inland Pond and Lake Islands, Inland Streams and Rivers, Inland Stream and River Islands, using Esri functionality. All ground (ASPRS Class 2) lidar data inside of the collected inland breaklines were then classified to water (ASPRS Class 9) using TerraScan macro functionality. A buffer of 0.7 meters was also used around each hydro-flattened feature. These points were moved from ground (ASPRS Class 2) to Ignored Ground (ASPRS Class 20). Breaklines are reviewed against lidar intensity imagery to verify completeness of capture. All breaklines are then compared to TINs (triangular irregular networks) created from ground only points prior to water classification. The horizontal placement of breaklines is compared to terrain features and the breakline elevations are compared to lidar elevations to ensure all breaklines match the lidar within acceptable tolerances. Some deviation is expected between breakline and lidar elevations due to monotonicity, connectivity, and flattening rules that are enforced on the breaklines. Once completeness, horizontal placement, and vertical variance is reviewed, all breaklines are reviewed for topological consistency and data integrity using a combination of ESRI Data Reviewer tools and proprietary tools. 20230715 Vector Universal Transverse Mercator 12 0.9996 -111.000000 0.000000 500000 0.000000 coordinate pair 0.010000 0.010000 meters North American Datum of 1983 (2011) Geodetic Reference System 80 6378137.000000 298.257222 North American Vertical Datum of 1988, Geoid 18 0.01 meters Explicit elevation coordinate included with horizontal coordinates 20231117 20231117 Aero-Graphics, Inc. mailing and physical

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Salt Lake City UT 84115 USA (801)487-3273 FGDC Content Standard for Digital Geospatial Metadata FGDC-STD-001-1998 None. None. None. Unclassified. None. None. None.