Peter Dartnell Andrew W. Stevens Jessica R. Lacy 20250820 GeoTIFF data release DOI:10.5066/P14D723N Pacific Coastal and Marine Science Center, Santa Cruz, California U.S. Geological Survey https://doi.org/10.5066/P14D723N Samantha C. McGill Jessica R. Lacy Andrew W. Stevens Rachel M. Allen Peter Dartnell Joanne C. Thede Angela C. Tan Gerald A. Hatcher 2025 data release doi:10.5066/P14D723N Pacific Coastal and Marine Science Center, Santa Cruz, California U.S. Geological Survey Suggested Citation: McGill, S.C., Lacy, J.R., Stevens, A.W., Allen, R.M., Dartnell, P., Thede, J.C., Tan, A.C., and Hatcher, G.A., 2025, Hydrodynamic, bathymetric, and sediment transport data spanning dredge material placement in south San Francisco Bay, California, 2023-2025: U.S. Geological Survey data release, https://doi.org/10.5066/P14D723N. https://doi.org/10.5066/P14D723N Acoustic-backscatter data were collected with a 234 kHz SwathPlus interferometric side-scan sonar during repeat bathymetric surveys of south San Francisco Bay, California between 2023 and 2025. Data were collected and processed by the U.S. Geological Survey (USGS), Pacific Coastal and Marine Science Center (PCMSC) with fieldwork activity number 2023-655-FA. Data are provided as a GeoTIFF images. Repeat bathymetric and acoustic backscatter data were collected between October 2023 and January 2025 to quantify the initial deposition and dispersal of fine-grained (less than 63 micron) sediment deposits formed when 73,000 cubic meters of sediment dredged from the Redwood City navigation channel was placed in the shallows of south San Francisco Bay, California. The swath sonar system consisted of a 234 kHz SwathPlus interferometric side scan sonar and POS-MV WaveMaster-II positioning system. The surveys were conducted on October 25-26, 2023, January 8-9, 2024, January 23-25, 2024, March 6-8, 2024, October 15-16, 2024, January 14-15, 2025. Additional information about the field activity from which these data were derived is available online at: https://cmgds.marine.usgs.gov/fan_info.php?fan=2023-655-FA Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Although this Federal Geographic Data Committee-compliant metadata file is intended to document the data set in nonproprietary form, as well as in Esri format, this metadata file may include some Esri-specific terminology. 20231025 20250115 ground condition at time data were collected. Complete None planned -122.182946 -122.168298 37.607479 37.577268 USGS Metadata Identifier USGS:701d3957-86f5-492b-96c9-bc58bbccbc33 ISO 19115 Topic Category geoscientificInformation elevation USGS Thesaurus sea-floor acoustic reflectivity geospatial datasets marine geophysics sonar methods Data Categories for Marine Planning Substrate Marine Realms Information Bank (MRIB) Keywords field observation none U.S. Geological Survey USGS Coastal and Marine Hazards and Resources Program CMHRP Pacific Coastal and Marine Science Center PCMSC Geographic Names Information System (GNIS) San Francisco Bay State of California none South San Francisco Bay Eden Landing Ecological Reserve No access constraints USGS-authored or produced data and information are in the public domain from the U.S. Government and are freely redistributable with proper metadata and source attribution. Please recognize and acknowledge the U.S. Geological Survey as the originators of the dataset and in products derived from these data. This information is not intended for navigation purposes. U.S. Geological Survey, Pacific Coastal and Marine Science Center PCMSC Science Data Coordinator mailing and physical

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Santa Cruz CA 95060 831-427-4747 pcmsc_data@usgs.gov DMP23_backscatter_intensity.png Maps showing acoustic backscatter for each SwathPlus survey. PNG Matlab version 2024a on a Windows 11 computer. No formal attribute accuracy tests were conducted. No formal logical accuracy tests were conducted. Dataset 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 Applanix POS-MV post-processed horizontal positional accuracy is about 0.1 m with roll and pitch accuracies of about 0.02 degrees (https://www.applanix.com/downloads/products/specs/posmv/POS-MV-WaveMaster-II.pdf). Accuracies of final products may be lower due to total propagated uncertainties of the mapping systems, which include sonar system, position and motion compensation system, and navigation, as well as data processing that includes sounding cleaning, gridding, and datum transformations. Not applicable to acoustic-backscatter data. Surveys were conducted on October 25-26, 2023, January 8-9, 2024, January 23-25, 2024, March 6-8, 2024, October 15-16, 2024, January 14-15, 2025. All six surveys were conducted using the same mapping systems and post-processed using the same methodology. The data were collected with a SWATHplus-M 234-kHz interferometric side-scan sonar system pole-mounted on the U.S. Geological Survey (USGS) R/V Parke Snavely. During the mapping mission, an Applanix POS-MV (Position and Orientation System for Marine Vessels) was used to position the vessel during data collection, and it also accounted for vessel motion such as heave, pitch, and roll. The POS-MV also recorded position and vessel motion parameters for later post-processing. Sound-velocity profiles were collected throughout the survey days with a Castaway CTD. Post-processed POS-MV Smoothed Best Estimate of Trajectory (SBET) files were merged with the survey line files using BathySwath software and then the line files were imported into SonarWiz software. Acoustic-backscatter data were processed using SonarWiz software techniques and gridded into 1-m resolution images. The images were exported as Erdas Imagine files in UTM zone 10, WGS-84 coordinates and imported into a GIS (ArcGIS Pro). The images were then projected to UTM zone 10, NAD83(2011) coordinates using ArcTools raster projection tool. The images were exported as a GeoTIFF file in UTM zone 10, NAD83(2011) coordinates. 2025 Raster Grid Cell 3343 1266 1 Universal Transverse Mercator 10 0.9996 -123.00000 0.00000 500000.0 0.00 coordinate pair 1.0 1.0 Meters North American Datum of 1983, 2011 realization (NAD83(2011)) GRS80 6378137.00 298.257222101 Attribute Table backscatter intensity as a digital value Producer defined Value Acoustic-backscatter value. No data value is -9999. Producer Defined 0 274 none The complete 1-m resolution of south San Francisco Bay backscatter raster is an 8-bit integer raster. It has a minimum (least reflective) value of 0 and a maximum (most reflective) value of 274. U.S. Geological Survey U.S. Geological Survey - CMGDS Mailing and Physical

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Santa Cruz CA 95060 831-427-4747 pcmsc_data@usgs.gov These data are available in GeoTIFF format, accompanied by CSDGM FGDC-compliant metadata. The survey dates and type of sonar used in the surveys are denoted in the filenames according to the following convention: yyyy_mm_dd_bs.tif, where "yyyy" denotes the survey year, "mm" denotes the survey month, and "dd" is the final day of data collection. 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. GeoTIFF Globalmapper (version 23.0) Downloadable zip file contains the TIFF (.tif) version of the acoustic-backscatter data and a projection file (.tfw). WinZip 5.4 https://doi.org/10.5066/P14D723N Data and metadata can be downloaded using the Network_Resource_Name link and scrolling down to the Sidescan Data section. None. The downloadable data file has been compressed with the "zip" command and can be unzipped with Winzip (or other tool) on Windows systems. To utilize these data, the user must have software capable of uncompressing the WinZip file and importing and viewing a GeoTIFF file. 20250820 U.S. Geological Survey, Pacific Coastal and Marine Science Center PCMSC Science Data Coordinator mailing and physical

2885 Mission Street

Santa Cruz CA 95060 831-427-4747 pcmsc_data@usgs.gov Content Standard for Digital Geospatial Metadata FGDC-STD-001-1998