Metadata: Identification_Information: Citation: Citation_Information: Originator: Joshua B. Logan Originator: Amy E. East Publication_Date: 20231030 Title: Digital Elevation Model of Oxbow Reservoir, Placer County, California, October 2022 Geospatial_Data_Presentation_Form: GeoTIFF Series_Information: Series_Name: data release Issue_Identification: DOI:10.5066/P9B39W4J Publication_Information: Publication_Place: Pacific Coastal and Marine Science Center, Santa Cruz, California Publisher: U.S. Geological Survey Online_Linkage: https://doi.org/10.5066/P9B39W4J Online_Linkage: https://www.sciencebase.gov/catalog/item/65135f92d34eeedefc13c19f Larger_Work_Citation: Citation_Information: Originator: Joshua B. Logan Originator: Amy E. East Publication_Date: 2023 Title: Topographic survey data and digital elevation model of Oxbow Reservoir, Placer County, California, October 2022 Series_Information: Series_Name: data release Issue_Identification: DOI:10.5066/P9B39W4J Publication_Information: Publication_Place: Pacific Coastal and Marine Science Center, Santa Cruz, CA Publisher: U.S. Geological Survey Other_Citation_Details: Suggested Citation: Logan, J.B. and East, A.E., 2023, Topographic survey data and digital elevation model of Oxbow Reservoir, Placer County, California, October 2022: U.S. Geological Survey data release, https://doi.org/10.5066/P9B39W4J. Online_Linkage: https://doi.org/10.5066/P9B39W4J Online_Linkage: https://www.sciencebase.gov/catalog/item/65135edad34eeedefc13bff0 Description: Abstract: This portion of the data release presents a digital elevation model (DEM) of portions of Oxbow Reservoir in Placer County, California. The DEM was created using topographic survey data collected on 26 October 2022, when the reservoir was partially de-watered to allow repairs to the dam infrastructure following the Mosquito Fire. Although the gates of the dam were open during this time, significant portions of the reservoir site remained inaccessible to surveyors due to the continued flow of the Middle Fork American River. Consequently, this DEM covers approximately 50 percent of the total surface area of the reservoir at full pool. The raw topographic data for the DEM were collected using two RTK GNSS backpack rovers which were referenced to a temporary GNSS base station occupying a fixed control point ("CP512") located less than 1 kilometer from the survey area. Precise coordinates for the GNSS base station were derived using the National Geodetic Survey (NGS) Online Positioning User Service (OPUS). The GNSS data were used to create a triangulated irregular network (TIN), which was converted to raster DEM. The resulting DEM has a horizontal resolution of 1 meter and is formatted as a GeoTIFF. Purpose: These data are intended to be used as a record of baseline bottom sediment elevation in Oxbow Reservoir immediately after the Mosquito Fire, prior to the first post-fire runoff of the winter of 2022-2023. Supplemental_Information: 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=2022-666-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 dataset in nonproprietary form, as well as in Esri format, this metadata file may include some Esri-specific terminology. Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 20221026 Currentness_Reference: ground condition at time data were collected Status: Progress: Complete Maintenance_and_Update_Frequency: None planned Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -120.74457 East_Bounding_Coordinate: -120.73185 North_Bounding_Coordinate: 39.00609 South_Bounding_Coordinate: 39.00018 Keywords: Theme: Theme_Keyword_Thesaurus: ISO 19115 Topic Category Theme_Keyword: elevation Theme_Keyword: geoscientificInformation Theme: Theme_Keyword_Thesaurus: Data Categories for Marine Planning Theme_Keyword: Bathymetry and Elevation Theme: Theme_Keyword_Thesaurus: USGS Thesaurus Theme_Keyword: topography Theme_Keyword: topographic maps Theme_Keyword: geomorphology Theme_Keyword: geospatial datasets Theme: Theme_Keyword_Thesaurus: Marine Realms Information Bank (MRIB) keywords Theme_Keyword: topographic mapping Theme: Theme_Keyword_Thesaurus: None Theme_Keyword: U.S. Geological Survey Theme_Keyword: USGS Theme_Keyword: Coastal and Marine Hazards and Resources Program Theme_Keyword: CHMRP Theme_Keyword: Pacific Coastal and Marine Science Center Theme_Keyword: PCMSC Theme: Theme_Keyword_Thesaurus: USGS Metadata Identifier Theme_Keyword: USGS:65135f92d34eeedefc13c19f Place: Place_Keyword_Thesaurus: Geographic Names Information System (GNIS) Place_Keyword: State of California Place_Keyword: Placer County Place_Keyword: Oxbow Reservoir Place_Keyword: Oxbow Bar Place_Keyword: Alabama Bar Place_Keyword: Middle Fork American River Place_Keyword: Rubicon River Access_Constraints: None Use_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 originator(s) of the dataset and in products derived from these data. This information is not intended for navigation purposes. Point_of_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey, Pacific Coastal and Marine Science Center Contact_Person: PCMSC Science Data Coordinator Contact_Address: Address_Type: mailing and physical Address: 2885 Mission Street City: Santa Cruz State_or_Province: CA Postal_Code: 95060 Contact_Voice_Telephone: 831-427-4747 Contact_Electronic_Mail_Address: pcmsc_data@usgs.gov Browse_Graphic: Browse_Graphic_File_Name: https://www.sciencebase.gov/catalog/file/get/65135f92d34eeedefc13c19f?name=OxbowReservoirDEM_browse.jpg&allowOpen=true Browse_Graphic_File_Description: Color-shaded relief image of the Oxbow Reservoir DEM. Browse_Graphic_File_Type: JPEG Native_Data_Set_Environment: Microsoft Windows 10, Trimble Business Center 5.9.0, ESRI ArcGIS Pro 2.9.1 Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: No formal attribute accuracy tests were conducted. Logical_Consistency_Report: No formal logical accuracy tests were conducted. Completeness_Report: Dataset is considered complete for the information presented, as described in the abstract. During the survey significant portions of the reservoir bottom remained under water and inaccessible to surveyors. Consequently, this DEM covers approximately 50 percent of the total surface area of the reservoir at full pool. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: No formal horizontal accuracy tests were performed. The topographic survey data used to create the DEM were collected using multi-constellation dual-frequency RTK GNSS rovers receiving differential corrections from a base station operating less than 1 kilometer away. The average estimated horizontal precision of the topographic survey data was 0.028 meters at the 95 percent confidence level. Additional uncertainty related to the reference position of the GNSS base station is estimated to be 0.040 at the 95 percent confidence level, based on the NGS OPUS position solution report which was used to derive the position. Combining the estimated single point precision of the topographic survey data with the estimated uncertainty in the position of the GNSS base station reference point results in a total estimated horizontal accuracy of 0.049 meters at the 95 percent confidence level. Additional sources of error such as antenna height measurement errors, and errors resulting from the GPS antenna not being perfectly level during continuous surveying sessions may be present in the data but the magnitudes of such errors are unknown. It should be noted that the magnitudes of these errors are exceeded by the 1-meter horizontal resolution of the DEM. Vertical_Positional_Accuracy: Vertical_Positional_Accuracy_Report: Vertical accuracy of the DEM was estimated by withholding 631 randomly selected check points from the original topographic survey data set and comparing the elevations of those points with the DEM. The resulting vertical RMSE for these 631 points was 0.101 meters (0.198 meters at the 95 percent confidence level) which represents the relative precision of the DEM. Additional uncertainty related to the reference position of the GNSS base station is estimated to be 0.064 meters (0.125 at the 95 percent confidence level), based on the NGS OPUS position solution report which was used to derive the position. Combining the vertical RMSE of the DEM with the estimated uncertainty in the position of the GNSS base station reference point results in a total estimated vertical accuracy of 0.120 meters (0.234 meters at the 95 percent confidence level). It should be noted that there are likely additional interpolation errors with unknown magnitudes in some portions of the DEM resulting from interpolation across breaks in slope which may have been poorly defined during the topographic survey. Lineage: Process_Step: Process_Description: A topographic survey was conducted using two multi-constellation dual-frequency RTK GNSS rovers (Trimble R10-2) receiving differential corrections from a GNSS base station operating less than 1 kilometer away. The rovers were mounted on GPS backpacks, and were operated in continuous survey mode, collecting data at rate of 1 Hz. The surveyors walked on all exposed reservoir sediment bars which were accessible during the survey. The surveyors attempted to survey along breaks in slope, water surface elevation contours, with additional data in broad planar areas in order to adequately define the topographic surface. Additional survey data were collected along pre-defined "zig-zag" transects which could be re-occupied with a boat during a possible future bathymetric survey with the reservoir at full pool. The GNSS base station was placed on an existing control point, "CP512", on the west shoulder of Tahoe National Forest Road 0023-004, approximately 100 meters north of the reservoir below the junction with Forest Road 0023 and Forest Road 0023-02. The reference position provided for CP512 were: CP512-PCWA (SPCS83 California zone 2, ft) Northing: 2129745.418 Easting: 6919711.944 Elevation: 1486.07 (assumed ft., NGVD29) During the RTK survey, the GNSS base station was set to collect static observations, and these were submitted to the National Geodetic Survey (NGS) Online Positioning User Service (OPUS-S). The OPUS solution was of high quality, conforming to USGS Level III quality for a single-base OPUS-S survey. The coordinates of the OPUS-S solution are below: CP512-USGS (NAD83(2011) UTM Zone 10, meters) Northing: 4319590.574 Easting: 695699.448 Elevation: 453.791 (NAVD88, meters, derived using GEOID18) The newly derived position for CP512 was used to adjust all of the topographic survey data collected during the survey. Process_Date: 20221026 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Joshua Logan Contact_Organization: U.S. Geological Survey, Pacific Coastal and Marine Science Center Contact_Address: Address_Type: mailing and physical Address: 2885 Mission Street City: Santa Cruz State_or_Province: CA Postal_Code: 95060 Contact_Voice_Telephone: 831-460-7519 Contact_Electronic_Mail_Address: jlogan@usgs.gov Process_Step: Process_Description: DEM development: 1. Topographic data points were filtered to remove points with poor estimated vertical accuracy. 2. Approximately 3 percent of the remaining points (n=631) were randomly selected and withheld from the data set to serve as a validation set (described in the Vertical Positional Accuracy portion of this document). 3. ArcGIS Pro was used to create a Triangulated Irregular Network (TIN) with the remaining points. 4. Breaklines were added manually along the main river channel portions to reduce interpolation errors in these locations. 5. The TIN was edited to define the interpolation boundary extent (removing long triangles from the exterior). 6. The TIN was exported to a GeoTIFF raster with a pixel resolution of 1 meter. Process_Date: 2023 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Joshua Logan Contact_Organization: U.S. Geological Survey, Pacific Coastal and Marine Science Center Contact_Position: Physical Scientist Contact_Address: Address_Type: mailing address Address: 2885 Mission Street City: Santa Cruz State_or_Province: CA Postal_Code: 95060 Country: US Contact_Voice_Telephone: 831-460-7519 Contact_Facsimile_Telephone: 831-427-4748 Contact_Electronic_Mail_Address: jlogan@usgs.gov Spatial_Data_Organization_Information: Direct_Spatial_Reference_Method: Raster Raster_Object_Information: Raster_Object_Type: Grid Cell Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Planar: Grid_Coordinate_System: Grid_Coordinate_System_Name: Universal Transverse Mercator Universal_Transverse_Mercator: UTM_Zone_Number: 10 Transverse_Mercator: Scale_Factor_at_Central_Meridian: 0.9996 Longitude_of_Central_Meridian: -123.0 Latitude_of_Projection_Origin: 0.0 False_Easting: 500000.0 False_Northing: 0.0 Planar_Coordinate_Information: Planar_Coordinate_Encoding_Method: row and column Coordinate_Representation: Abscissa_Resolution: 1.000 Ordinate_Resolution: 1.000 Planar_Distance_Units: meters Geodetic_Model: Horizontal_Datum_Name: NAD83 (National Spatial Reference System 2011) (EPSG:1116) Ellipsoid_Name: GRS 1980 (EPSG:7019) Semi-major_Axis: 6378137.0 Denominator_of_Flattening_Ratio: 298.257222101 Vertical_Coordinate_System_Definition: Altitude_System_Definition: Altitude_Datum_Name: North American Vertical Datum of 1988 (EPSG:5703), derived using GEOID18 Altitude_Resolution: 0.001 Altitude_Distance_Units: meters Altitude_Encoding_Method: Explicit elevation coordinate included with horizontal coordinates Entity_and_Attribute_Information: Detailed_Description: Entity_Type: Entity_Type_Label: GeoTIFF Entity_Type_Definition: GeoTIFF containing elevation values. Entity_Type_Definition_Source: Producer defined Overview_Description: Entity_and_Attribute_Overview: GeoTIFF raster contains elevations in meters relative to the North American Vertical Datum of 1988 (NAVD88). Entity_and_Attribute_Detail_Citation: U.S. Geological Survey Distribution_Information: Distributor: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey - ScienceBase Contact_Address: Address_Type: mailing address Address: Denver Federal Center, Building 810, Mail Stop 302 City: Denver State_or_Province: CO Postal_Code: 80225 Country: United States Contact_Voice_Telephone: 1-888-275-8747 Contact_Electronic_Mail_Address: sciencebase@usgs.gov Resource_Description: The Oxbow Reservoir DEM is available as a GeoTIFF file. Distribution_Liability: 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. Standard_Order_Process: Digital_Form: Digital_Transfer_Information: Format_Name: GeoTIFF Format_Version_Number: GeoTIFF 1.1 Format_Information_Content: GeoTIFF contains a Digital Elevation Model (DEM) with single-precision floating-point values compressed using the LZW lossless compression method. No data value is -32767. File_Decompression_Technique: none Transfer_Size: 0.432 Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: https://doi.org/10.5066/P9B39W4J Network_Resource_Name: https://www.sciencebase.gov/catalog/file/get/65135f92d34eeedefc13c19f?name=OxbowReservoir_2022-10-26_DEM_1m.tif Network_Resource_Name: https://www.sciencebase.gov/catalog/item/65135f92d34eeedefc13c19f Access_Instructions: Data can be downloaded using the Network_Resource_Name links. The first link is direct link to download the DEM in GeoTIFF format. The second link points to a landing page with the DEM, metadata, and a browse image. The third link points to the landing page for the entire data release, including links to pages of the various data files. Fees: None. Technical_Prerequisites: These data can be viewed with GIS software or other software capable of displaying geospatial raster data. Metadata_Reference_Information: Metadata_Date: 20231030 Metadata_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey, Pacific Coastal and Marine Science Center Contact_Person: PCMSC Science Data Coordinator Contact_Address: Address_Type: mailing and physical Address: 2885 Mission Street City: Santa Cruz State_or_Province: CA Postal_Code: 95060 Contact_Voice_Telephone: 831-427-4747 Contact_Electronic_Mail_Address: pcmsc_data@usgs.gov Metadata_Standard_Name: Content Standard for Digital Geospatial Metadata Metadata_Standard_Version: FGDC-STD-001-1998