Jenny L. Hanson Jayme M. Strange 20210201 raster digital data https://doi.org/10.5066/P9O0QH8B The U.S. Geological Survey (USGS) collected hydroacoustic data of the St. Croix River adjacent to the Osceola (WI) boat ramp for hydrographic and benthic mapping prior to the reconstruction project implemented by the National Park Service (NPS). Sidescan image mosaics are often used in benthic mapping because it provides a picture of the physical bed characteristics. Sidescan sonar collects data over a relatively large area based on differences in acoustic reflectance signature. These datasets were desired by the NPS to help inform and mitigate potential impacts to mussels or benthic habitat. The NPS has been planning the reconstruction of the Osceola, WI boat ramp within the St. Croix National Scenic Riverway. Prior to construction, the NPS wanted to complete hydrographic/topographic surveys and maps of the river bottom adjacent to the boat ramp to mitigate potential impacts to mussels or benthic habitat. Effective mapping, analysis, and visualization of river habitat is important because the river bed environment is not readily viewed directly by eye. Multibeam Echo Sounder (MBES) systems produce high-resolution bathymetry and backscatter data that can be used to obtain information about the sediment composition and physical properties of the riverbed. Acoustic Doppler current profilers (ADCP) measuring river current velocities are a desired component needed to model physical and hydraulic variables in relation to native mussel habitat. Lidar collected simultaneously with bathymetry data provides topographic information along the shorelines which relates the river bank to the adjacent uplands and floodplain functions. Development of these spatial visualization tools provides viewing of modeled datasets in a digital environment to better understand the complex benthic habitat corridors where freshwater mussels reside, and will provide resource managers information to more accurately assess environmental factors that influence mussel distributions. 20191016 ground condition Complete None planned -92.719300 -92.707700 45.323600 45.315200 ISO 19115 Topic Category biota USGS Thesaurus sidescan sonar image mosaics multibeam sonar bathymetry sea-floor acoustic reflectivity Alexandria Digital Library Feature Type Thesaurus seafloor features USGS Metadata Identifier USGS:6014320cd34e162231feda5f Common geographic areas Wisconsin Minnesota St. Croix 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 608-783-8058 jhanson@usgs.gov National Park Service Denver Service Center; National Park Service St. Croix National Scenic Riverway No formal attribute accuracy tests were conducted. No formal logical accuracy tests were conducted. 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. A Waterman 18' boat equipped with a Norbit iWBMS (serial # 22) multibeam sonar collected bathymetry and backscatter data on October 16, 2019. The multibeam was mounted on the boat with a mobile, light-weight, carbon fibered pole mount. Two Novetel antennas were mounted above the multibeam sonar and communicated with the Novatel IMU within the Norbit multibeam system. Multibeam data was collected at 400 kHz. A patch test was measured to compensate for pitch, roll, and yaw. Velocity, water temperature, and depth were sampled using the Norbit Sound Velocity Profiler before, during, and after the survey. 20191016 Raw HSX data files were edited using the Hypack (2019) Targeting and Mosaicking program. Each raw sidescan file was visually examined using the Scan View Mode to remove positional spikes by smoothing the track lines. The Mosaic Mode was used to export sidescan data to a mosaic and/or exported individual transect lines as .tif images. The images were exported to a 0.05m resolution for interpretation purposes. 20191031 The exported mosaics and/or transect lines were imported into ArcGIS (v10.7) for additional editing. Some of the individual exported transect images were clipped and mosaicked using ArcGIS to cover areas that needed better image cover. Once complete, the mosaic was clipped to a study area boundary that was manually delineated around the shoreline or sonar reach. All sonar images were internally reviewed for anomalies. 20200110 The sidescan mosaic required a spatial adjustment to compensate for using raw HSX files to generate the image mosaic (the smoothed best estimated trajectory (SBET) file could not be applied). The raster dataset was permanently transformed after applying georeferenced control points to the bathymetry data using the Georeferencing Toolbar in Esri's ArcGIS (version 10.7). 20200128 Raster Grid Cell 15585 21592 1 5.377371994799564e-07 5.377371994800351e-07 Decimal seconds WGS_1984 WGS 84 6378137.0 298.257223563 Osceola_sidescan_wgs84.tif Raster geospatial data file. Producer Defined Value Unique numeric values contained in each raster cell. Producer Defined 0.0 255.0 GS ScienceBase U.S. Geological Survey mailing address

Denver Federal Center, Building 810, Mail Stop 302

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 on any other system or for general or scientific purposes, nor shall the act of distribution constitute any such warranty. 20211103 Jenny L Hanson U.S. Geological Survey, MIDCONTINENT REGION Biologist mailing address

2630 Fanta Reed Road

La Crosse WI 54603 US 608-781-6372 608-783-8058 jhanson@usgs.gov FGDC Content Standard for Digital Geospatial Metadata FGDC-STD-001-1998