Jenny L Hanson Stephanie R Sattler John W Lund 20240912 raster digital data https://doi.org/10.5066/P9JH0O1X Daniel M Wagner John W Lund Kelly M Sanks 20200710 raster digital data https://www.sciencebase.gov U.S. Geological Survey https://doi.org/10.5066/p9gxt1x1 This dataset is a digital elevation model (DEM) of the beach topography of Lake Superior at the Duluth Entry, Duluth, Minnesota. The DEM has a 1-meter (m; 3.28084 feet) cell size and was created from a LAS dataset of terrestrial light detection and ranging (lidar) data representing the beach topography. Lidar data were collected July 28, 2020 using a boat mounted Velodyne unit. Methodology similar to Wagner, D.M., Lund, J.W., and Sanks, K.M., 2020 was used. Data were collected in cooperation with the U.S. Army Corps of Engineers (USACE), Detroit District, to define beach topography and near-shore bathymetry prior to beach nourishment in areas around the Duluth Entry to Lake Superior that have been scoured by high water levels and heavy wave activity. This survey was completed to obtain baseline data and establish pre-nourishment conditions before placing dredge spoils to mitigate beach erosion. The DEM is intended to be used as a comparison with pre-nourishment surveys, and is provided in GeoTiff format. Lidar patch test values were estimated but a patch test was not formally conducted. The uncertainty of the lidar is unknown. Post data release, we found discernible errors in the positioning. Please use the data with caution 20200728 ground condition Complete None planned -92.09220 -92.07930 46.78210 46.76190 ISO 19115 Topic Category elevation inlandWaters Data Categories for Marine Planning Bathymetry and Elevation USGS Thesaurus limnology lidar digital elevation models bathymetry USGS Metadata Identifier USGS:60677264d34edc0435c09d4f Common geographic areas Southwestern Lake Superior Great Lakes Duluth Lake Superior None. Please see 'Distribution Info' for details. None. Users are advised to read the dataset's metadata thoroughly to understand appropriate use and data limitations. Jenny L Hanson U.S. Geological Survey, MIDCONTINENT REGION Biologist mailing address

2630 Fanta Reed Road

La Crosse WI 54603 US 608-781-6372 608-783-6066 jhanson@usgs.gov Funding for the project was provided by the Great Lakes Restoration Initiative (GLRI) in cooperation with the USACE, Detroit District. The Mounds View, MN office of the USGS Upper Midwest Water Science Center (UMID) teamed up with the La Crosse, WI USGS Upper Midwest Environmental Sciences Center (UMESC) to collect the lidar and multibeam data, using the UMESC's Velodyne puck and Norbit iWBMSc mounted on UMID's boat. Environment as of Metadata Creation: Microsoft Windows 10 Enterprise; Xylem's Hypack 2020; GeoCue's LP360 version 2020.1.80.0; Esri ArcGIS for Desktop version 10.7.1; Waypoint Inertial Explorer version 8.90 Daniel M Wagner John W Lund Kelly M Sanks 20200720 dataset https://www.sciencebase.gov U.S. Geological Survey https://doi.org/10.5066/p9gxt1x1 Prior to the bathymetric survey, a boresight calibration procedure was performed to determine the alignment offsets between reference frame of the sonar and that of the inertial measurement unit (IMU) that is part of the positioning system. Lidar and bathymetry were surveyed simultaneously, and the data quality were assessed continuously by the computer operator. Data-quality flags and alarms from the lidar, multibeam, and positioning systems were noted and investigated. Lidar patch test values were estimated in post-processing, but a patch test was not formally conducted during acquisition. The uncertainty of the lidar is unknown. Please use the data with caution. Positions and elevations of the point data from which the DEM and contours were derived fall within expected ranges and plot in the correct locations on available aerial imagery. A survey area was provided by the USACE (Detroit district), to show the area of interest along Minnesota Point near the Duluth Entry to the Duluth Harbor Basin. The beach face was surveyed from approximately 0.0.24 kilometers (km; 0.15 miles [mi]) north of the Duluth Entry pier to 2 kilometers (km; 1.24 miles [mi]) south of the pier along the beach. During the survey, position and elevation data were collected using a NovAtel MarineSPAN Global Navigation Satellite System/Inertial Navigation System (GNSS/INS). The accuracy of the positioning data was improved in post-processing using the daily static occupations of a nearby National Geodetic Survey (NGS) Continuously Operating Reference Station (CORS). The data files from the daily static occupations were processed in WayPoint Inertial Explorer using the precise point kinematic method to help correct the 3D positioning location. The final navigation solution (called a smoothed best estimate of trajectory, or SBET, solution) was applied to the lidar and multibeam sonar data during post-processing. The estimated position accuracy for the solutions were calculated for the estimated standard deviation of less than 0.07 m (0.23 ft) in the X, or "easting", direction and less than 0.07 m (0.23 ft) in the Y, or "northing direction for July 28, 2020. During the survey, position and elevation data were collected using an NovAtel MarineSPAN Global Navigation Satellite System/Inertial Navigation System (GNSS/INS). The accuracy of the positioning data was improved in post-processing using the daily static occupations of a nearby National Geodetic Survey (NGS) Continuously Operating Reference Station (CORS). The data files from the daily static occupations were processed in WayPoint Inertial Explorer using the precise point kinematic method to help correct the 3D positioning location. The final navigation solution (called a smoothed best estimate of trajectory, or SBET, solution) was applied to the lidar and multibeam sonar data during post-processing. The estimated standard deviation of the Z ("down", or vertical) direction was less than 0.14 m (0.46 ft) for July 28, 2020. To correct vertical soundings to the International Great Lakes Datum conversion 1985 (IGLD 85), the Hypack geodesy settings were predefined to add a height above chart datum, by calculating the hydraulic corrector, or conversion between the dynamic height and the IGLD 85 height. Combined with the National Oceanic and Atmospheric Administration (NOAA) tide station 9099064 (located at the Duluth entry to the harbor on the northwest end of Minnesota Point, https://tidesandcurrents.noaa.gov/stationhome.html?id=9099064), the water surface elevation was vertically referenced for the lidar and multibeam data. Lidar data were collected using a Velodyne VLP-16 unit mounted to the port side of the survey vessel. The Velodyne VLP-16 was coupled to a NovAtel positioning system for position and motion corrections. Lidar data were collected simultaneously with a Norbit iWBMSc multibeam system, angled 90 degrees to the shoreline. 20200728 Data collected with the NovAtel's positioning system during the lidar and multibeam sonar surveys were post-processed using version 8.90 of Waypoint Inertial Explorer software. The horizontal and vertical accuracy of the differential global navigation and satellite systems (GNSS) solution was improved in post-processing by correcting the navigation solution based on the average solution of the daily occupations of nearby National Geodetic Survey (NGS) Continuously Operating Reference Stations (CORS). The post-processed navigation solution, known as a smoothed best estimate of trajectory (SBET) solution, was exported to a file for use in post-processing of lidar and multibeam sonar data. 20200728 Raw data collected with the Velodyne were edited using Hysweep's MBMAX64 module of Hypack 2020 software. The SBET solution from the NovAtel Inertial Explorer position system were applied to the lidar data in Hypack 2020 MBMAX64. 20201022 The water-surface elevation from the National Oceanic and Atmospheric Administration (NOAA) Duluth, Minnesota, tide station (9099064) was applied to the lidar data as the vertical reference. The lidar data were exported from Hypack in LAS format. 20201022 Lidar data were classified using LP360 software. High and low noise were classified into the ignored ground class. Vegetation was classified into the medium-vegetation class. The data were examined in three dimensions; any remaining noise that was missed were reclassified. The LAS were exported with just the ground class remaining. The exported file was clipped to a boundary file (manually delineated) during the export. Using LP360 an elevation surface, or DEM, was generated at a 1-meter resolution. 20201115 The DEM was imported into ArcGIS and converted to a GeoTiff. The Spatial Analyst Raster Calculator was used to calculate from meters to survey feet (m; 3.28084 feet). The DEM was clipped to the lidar survey area, and projected to the specified horizontal and vertical coordinates of North American Datum (NAD) of 1983 BLM Zone 15 North ft US and International Great Lakes Datum (IGLD) of 1985. The DEM was reviewed for quality assurance/quality control. 20201125 Raster Grid Cell 2229 960 1 Transverse_Mercator 1640416.67 0.0 0.0 -93.0 0.0 0.0 row and column 3.2808333333331876 3.2808333333329323 survey feet North_American_Datum_1983 GRS 1980 6378137.0 298.2572221010042 International Great Lakes Datum of 1985 0.01 feet Explicit elevation coordinate included with horizontal coordinates Lidar_Duluth_1m_ft.tif Raster geospatial data file. Producer Defined Value Elevation, feet above the International Great Lakes Datum of 1985 (IGLD85). Producer Defined 603.283 627.997 Feet US The entity and attribute information provided here describes the tabular data associated with the data set. Please review the detailed descriptions that are provided (the individual attribute descriptions) for information on the values that appear as fields/table entries of the data set. The entity and attribute information were generated by the individual and/or agency identified as the originator of the data set. Please review the rest of the metadata record for additional details and information. U.S. Geological Survey - ScienceBase mailing

Mail Stop 302

Denver CO 80225 United States 1-888-275-8747 sciencebase@usgs.gov Although these data have been processed successfully on a computer system at the 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. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Vector Digital Data Sets https://doi.org/10.5066/P9JH0O1X None. No fees are applicable for obtaining the dataset. 20240912 Jenny L Hanson U.S. Geological Survey, MIDCONTINENT REGION Biologist mailing address

2630 Fanta Reed Road

La Crosse WI 54603 US 608-781-6372 608-783-6066 jhanson@usgs.gov FGDC Content Standard for Digital Geospatial Metadata FGDC-STD-001-1998