During autumn 2009 and winter 2010, the U.S. Geological Survey (USGS), in cooperation with the U.S. Army Corps of Engineers (USACE), conducted a hydrographic survey using a multibeam echosounder system (MBES). The survey was from river mile (RM) 130 to 142 on the Snake River, and from RM 0 to 2 on the Clearwater River areas of Lower Granite Reservoir. The survey mapped the part of the river that was accessible to the boat and the echosounder equipment, but very shallow areas along the banks that were inaccessible or too shallow to be measured with echosounder equipment were not mapped. The survey was conducted in 1-mile segments, and the data were combined to provide a continuous digital elevation dataset of the reservoir within the limitations of the project. The elevation points in the dataset were referenced to the USACE established benchmarks using the real-time kinematic-global positioning system (RTK-GPS); therefore, point elevations were unaffected by reservoir stage changes.

Water-supply lakes are the primary source of water for many communities throughout Missouri. Therefore, accurate and up-to-date estimates of lake capacity are important for managing and predicting adequate water-supply. Many of the water-supply lakes in Missouri were previously surveyed by the U.S. Geological Survey (USGS) in the early 2000s (Richards, 2013) and in 2013 (Huizinga, 2014); however, years of potential sedimentation may have resulted in reduced water storage capacity. Periodic bathymetric surveys are useful to update the area/capacity table and to determine changes in the bathymetric surface. In April and May 2023, the USGS, in cooperation with the Missouri Department of Natural Resources (MoDNR) and in collaboration with the cities of Adrian, Ironton, Unity Village, and Vandalia, Missouri, completed bathymetric surveys of six (6) lakes using a marine-based mobile mapping unit, which consists of a multibeam echosounder (MBES) and an inertial navigation system (INS) mounted on a marine survey vessel. Bathymetric data were collected as the vessel traversed longitudinal transects to provide nearly complete coverage of the lake. The MBES was electronically tilted in some areas to improve data collection along the shoreline, in coves, and in areas that are shallower than about 2.0 meters deep (the practical limit of reasonable and safe data collection with the MBES). At Adrian, supplemental data were collected in a shallow upper reservoir using an acoustic Doppler current profiler (ADCP) mounted on a remote-controlled vessel equipped with a differential global positioning system (DGPS). Bathymetric quality-assurance data also were collected at each lake to evaluate the vertical accuracy of the gridded bathymetric point data from the MBES. As part of the survey at each of these lakes, one or more reference marks or temporary benchmarks were established to provide a point of known location and elevation from which the water surface could be measured or another survey could be referenced at a later date. In addition, the elevation of a primary spillway or intake was surveyed, when present. These points were surveyed using a real-time kinematic (RTK) Global Navigation Satellite System (GNSS) receiver connected to the Missouri Department of Transportation real-time network (RTN), which provided real-time survey-grade horizontal and vertical positioning, using field procedures as described in Rydlund and Densmore (2012) for a Level II real-time positioning survey. The MBES data can be combined with light detection and ranging (lidar) data to prepare a bathymetric map and a surface area and capacity table for each lake. These data also can be used to compare the current bathymetric surface with any previous bathymetric surface. Data from each of the surveys are provided in ESRI Shapefile format (ESRI, 2023). Each of the six lakes surveyed in 2023 has a child page containing the metadata and two zip files, one for the bathymetric data, and the other for the bathymetric quality-assurance data. The zip files follow the format of "####2023_bathy_pts.zip" or ####2023_QA_raw.zip," where "####" is the lake name. Each of these zip files contains a shapefile with an attribute table. Attribute/column labels of each table are described in the "Entity and attribute" section of the associated metadata file. The various reference marks and additional points from all the lake surveys are provided in ESRI Shapefile format (ESRI, 2023) with an attribute table on the main landing page. Attribute/column labels of this table are described in the "Entity and attribute" section of the associated metadata file. References Cited: Environmental Systems Research Institute, 2023, ArcGIS: accessed July 12, 2023, at https://www.esri.com/en-us/arcgis/about-arcgis/overview. Huizinga, R.J., 2014, Bathymetric surveys and area/capacity tables of water-supply reservoirs for the city of Cameron, Missouri, July 2013: U.S. Geological Survey Open-File Report

Water-supply lakes are the primary source of water for many communities throughout Missouri. Therefore, accurate and up-to-date estimates of lake capacity are important for managing and predicting adequate water-supply. Many of the water-supply lakes in Missouri were previously surveyed by the U.S. Geological Survey (USGS) in the early 2000s (Richards, 2013) and in 2013 (Huizinga, 2014); however, years of potential sedimentation may have resulted in reduced water storage capacity. Periodic bathymetric surveys are useful to update the area/capacity table and to determine changes in the bathymetric surface. In April and May 2023, the USGS, in cooperation with the Missouri Department of Natural Resources (MoDNR) and in collaboration with the cities of Adrian, Ironton, Unity Village, and Vandalia, Missouri, completed bathymetric surveys of six (6) lakes using a marine-based mobile mapping unit, which consists of a multibeam echosounder (MBES) and an inertial navigation system (INS) mounted on a marine survey vessel. Bathymetric data were collected as the vessel traversed longitudinal transects to provide nearly complete coverage of the lake. The MBES was electronically tilted in some areas to improve data collection along the shoreline, in coves, and in areas that are shallower than about 2.0 meters deep (the practical limit of reasonable and safe data collection with the MBES). At Adrian, supplemental data were collected in a shallow upper reservoir using an acoustic Doppler current profiler (ADCP) mounted on a remote-controlled vessel equipped with a differential global positioning system (DGPS). Bathymetric quality-assurance data also were collected at each lake to evaluate the vertical accuracy of the gridded bathymetric point data from the MBES. As part of the survey at each of these lakes, one or more reference marks or temporary benchmarks were established to provide a point of known location and elevation from which the water surface could be measured or another survey could be referenced at a later date. In addition, the elevation of a primary spillway or intake was surveyed, when present. These points were surveyed using a real-time kinematic (RTK) Global Navigation Satellite System (GNSS) receiver connected to the Missouri Department of Transportation real-time network (RTN), which provided real-time survey-grade horizontal and vertical positioning, using field procedures as described in Rydlund and Densmore (2012) for a Level II real-time positioning survey. The MBES data can be combined with light detection and ranging (lidar) data to prepare a bathymetric map and a surface area and capacity table for each lake. These data also can be used to compare the current bathymetric surface with any previous bathymetric surface. Data from each of the surveys are provided in ESRI Shapefile format (ESRI, 2023). Each of the six lakes surveyed in 2023 has a child page containing the metadata and two zip files, one for the bathymetric data, and the other for the bathymetric quality-assurance data. The zip files follow the format of "####2023_bathy_pts.zip" or ####2023_QA_raw.zip," where "####" is the lake name. Each of these zip files contains a shapefile with an attribute table. Attribute/column labels of each table are described in the "Entity and attribute" section of the associated metadata file. The various reference marks and additional points from all the lake surveys are provided in ESRI Shapefile format (ESRI, 2023) with an attribute table on the main landing page. Attribute/column labels of this table are described in the "Entity and attribute" section of the associated metadata file. References Cited: Environmental Systems Research Institute, 2023, ArcGIS: accessed July 12, 2023, at https://www.esri.com/en-us/arcgis/about-arcgis/overview. Huizinga, R.J., 2014, Bathymetric surveys and area/capacity tables of water-supply reservoirs for the city of Cameron, Missouri, July 2013: U.S. Geological Survey Open-File Report

In 2008, the U.S. Geological Survey (USGS), Woods Hole Coastal and Marine Science Center (WHCMSC), in cooperation with the U.S. Army Corps of Engineers conducted a geophysical and sampling survey of the riverbed of the Upper St. Clair River between Port Huron, MI, and Sarnia, Ontario, Canada. The objectives were to define the Quaternary geologic framework of the St. Clair River to evaluate the relationship between morphologic change of the riverbed and underlying stratigraphy. This report presents the geophysical and sample data collected from the St. Clair River, May 29-June 6, 2008 as part of the International Upper Great Lakes Study, a 5-year project funded by the International Joint Commission of the United States and Canada to examine whether physical changes in the St. Clair River are affecting water levels within the upper Great Lakes, to assess regulation plans for outflows from Lake Superior, and to examine the potential effect of climate change on the Great Lakes water levels ( http://www.iugls.org). This document makes available the data that were used in a separate report, U.S. Geological Survey Open-File Report 2009-1137, which detailed the interpretations of the Quaternary geologic framework of the region. This report includes a description of the suite of high-resolution acoustic and sediment-sampling systems that were used to map the morphology, surficial sediment distribution, and underlying geology of the Upper St. Clair River during USGS field activity 2008-016-FA . Video and photographs of the riverbed were also collected and are included in this data release. Future analyses will be focused on substrate erosion and its effects on river-channel morphology and geometry. Ultimately, the International Upper Great Lakes Study will attempt to determine where physical changes in the St. Clair River affect water flow and, subsequently, water levels in the Upper Great Lakes.

In 2008, the U.S. Geological Survey (USGS), Woods Hole Coastal and Marine Science Center (WHCMSC), in cooperation with the U.S. Army Corps of Engineers conducted a geophysical and sampling survey of the riverbed of the Upper St. Clair River between Port Huron, MI, and Sarnia, Ontario, Canada. The objectives were to define the Quaternary geologic framework of the St. Clair River to evaluate the relationship between morphologic change of the riverbed and underlying stratigraphy. This report presents the geophysical and sample data collected from the St. Clair River, May 29-June 6, 2008 as part of the International Upper Great Lakes Study, a 5-year project funded by the International Joint Commission of the United States and Canada to examine whether physical changes in the St. Clair River are affecting water levels within the upper Great Lakes, to assess regulation plans for outflows from Lake Superior, and to examine the potential effect of climate change on the Great Lakes water levels ( http://www.iugls.org). This document makes available the data that were used in a separate report, U.S. Geological Survey Open-File Report 2009-1137, which detailed the interpretations of the Quaternary geologic framework of the region. This report includes a description of the suite of high-resolution acoustic and sediment-sampling systems that were used to map the morphology, surficial sediment distribution, and underlying geology of the Upper St. Clair River during USGS field activity 2008-016-FA . Video and photographs of the riverbed were also collected and are included in this data release. Future analyses will be focused on substrate erosion and its effects on river-channel morphology and geometry. Ultimately, the International Upper Great Lakes Study will attempt to determine where physical changes in the St. Clair River affect water flow and, subsequently, water levels in the Upper Great Lakes.

These data are high-resolution bathymetry (riverbed elevation) and depth-averaged velocities in ASCII format, generated from hydrographic and velocimetric surveys of the Missouri River near Structures L0550/A4497 on U.S. Highway 54 at Jefferson City, Missouri, in 2010, 2011, 2013, 2015, and 2017. Hydrographic data were collected using a high-resolution multibeam echosounder mapping system (MBMS), which consists of a multibeam echosounder (MBES) and an inertial navigation system (INS) mounted on a marine survey vessel. Data were collected as the vessel traversed the river along planned survey lines distributed throughout the reach. Data collection software integrated and stored the depth data from the MBES and the horizontal and vertical position and attitude data of the vessel from the INS in real time. Data processing required computer software to extract bathymetry data from the raw data files and to summarize and map the information.

This part of the data release contains high-resolution swath bathymetry data collected by the U.S. Geological Survey (USGS) Pacific Coastal and Marine Science Center at three locations in the Sacramento-San Joaquin Delta. Data were collected in Lindsey Slough in April 2017, Middle River in March 2018, and Mokelumne River in March 2018 using an interferometric bathymetric sidescan sonar systems mounted to the USGS R/V Parke Snavely. Data are provided in 1-m resolution GeoTIFF formats. These data were collected as part of a study on the effects of invasive aquatic vegetation on sediment transport in the Sacramento-San Joaquin Delta.

This part of the data release contains high-resolution swath bathymetry data collected by the U.S. Geological Survey (USGS) Pacific Coastal and Marine Science Center at three locations in the Sacramento-San Joaquin Delta. Data were collected in Lindsey Slough in April 2017, Middle River in March 2018, and Mokelumne River in March 2018 using an interferometric bathymetric sidescan sonar systems mounted to the USGS R/V Parke Snavely. Data are provided in 1-m resolution GeoTIFF formats. These data were collected as part of a study on the effects of invasive aquatic vegetation on sediment transport in the Sacramento-San Joaquin Delta.

Bathymetric LiDAR technology was used to collect riverbed elevation data along the Potomac River. In support of this effort, a bathymetric survey with a boat-mounted acoustic Doppler current profiler (ADCP) was conducted in the study area during October 4-7, 2021. The study area consisted of four verification reaches on the Potomac River including: 1) Williamsport accessed through the Williamsport Park boat ramp below Conococheague Creek and RTE 11 (Williamsport), 2) Big Slackwater above C&O Canal Dam #4 accessed through the Big Slackwater Boat Ramp (Dam4), 3) Four Locks above C&O Canal Dam #5 accessed through the Four Locks Boat Ramp (Dam5), and 4) Little Tonoloway Recreation Area accessed through the Hancock Boat Ramp below RTE 522. Global Navigational Satellite Systems (GNSS) were used to concurrently collect survey grade real-time kinematic (RTK) horizontal and vertical coordinates of the ADCP transducer face. The riverbed elevations were collected using the ADCP with WinRiverII to export for post-processing in Microsoft Excel and RStudio. The GNSS equipment was programmed to continuously collect an observation every 1 to 2 seconds and the ADCP was programmed to continuously collect an observation every 1 second to 2 seconds. The corrected depths from the 4 ADCP beams were averaged and then subtracted from the GNSS derived elevation of the ADCP transducer face to compute the elevation of the riverbed. All spatial data is referenced horizontally to the North American Datum of 1983 (2011) and vertically to the North American Vertical Datum of 1988 (NAVD88). Grid coordinates are projected in Universal Transverse Mercator Zone 18 North and are represented in meter units. This data release consists of four (4) comma-delimited (*.csv) files with fifteen columns each: GNSS_ID, Time_hh_mm_ss, GNSS_Northing_M, GNSS_Easting_M, Computed_Elevation_M, GNSS_Transducer_Elevation_M, Computed_Mean_Depth_M, GNSS_PDOP, GNSS_Vertical Precision_M, GNSS_Satellites, ADCP_Ensemble_ID, ADCP_Temp_C, ADCP_Pitch_Degrees, ADCP_Roll_Degrees, and Type. This data release supersedes a previous version (https://doi.org/10.5066/P9EA0IKM) which contained a constant error of +0.344 meters in the GNSS antenna height reference elevations.

Bathymetric LiDAR technology was used to collect riverbed elevation data along the Potomac River. In support of this effort, a bathymetric survey with a boat-mounted acoustic Doppler current profiler (ADCP) was conducted in the study area during October 4-7, 2021. The study area consisted of four verification reaches on the Potomac River including: 1) Williamsport accessed through the Williamsport Park boat ramp below Conococheague Creek and RTE 11 (Williamsport), 2) Big Slackwater above C&O Canal Dam #4 accessed through the Big Slackwater Boat Ramp (Dam4), 3) Four Locks above C&O Canal Dam #5 accessed through the Four Locks Boat Ramp (Dam5), and 4) Little Tonoloway Recreation Area accessed through the Hancock Boat Ramp below RTE 522. Global Navigational Satellite Systems (GNSS) were used to concurrently collect survey grade real-time kinematic (RTK) horizontal and vertical coordinates of the ADCP transducer face. The riverbed elevations were collected using the ADCP with WinRiverII to export for post-processing in Microsoft Excel and RStudio. The GNSS equipment was programmed to continuously collect an observation every 1 to 2 seconds and the ADCP was programmed to continuously collect an observation every 1 second to 2 seconds. The corrected depths from the 4 ADCP beams were averaged and then subtracted from the GNSS derived elevation of the ADCP transducer face to compute the elevation of the riverbed. All spatial data is referenced horizontally to the North American Datum of 1983 (2011) and vertically to the North American Vertical Datum of 1988 (NAVD88). Grid coordinates are projected in Universal Transverse Mercator Zone 18 North and are represented in meter units. This data release consists of four (4) comma-delimited (*.csv) files with fifteen columns each: GNSS_ID, Time_hh_mm_ss, GNSS_Northing_M, GNSS_Easting_M, Computed_Elevation_M, GNSS_Transducer_Elevation_M, Computed_Mean_Depth_M, GNSS_PDOP, GNSS_Vertical Precision_M, GNSS_Satellites, ADCP_Ensemble_ID, ADCP_Temp_C, ADCP_Pitch_Degrees, ADCP_Roll_Degrees, and Type. This data release supersedes a previous version (https://doi.org/10.5066/P9EA0IKM) which contained a constant error of +0.344 meters in the GNSS antenna height reference elevations.