Field-based real-time kinematic (RTK) GNSS surveys of water surface elevation and channel bed topography were collected along the Blue River, focusing on two cross-sections from which remotely sensed data were obtained. These data were used to assess the accuracy of river bed elevations inferred from the ASTRALiTe bathymetric lidar, acquired from an unmanned aircraft system (UAS). These data sets were collected to support research focused on developing innovative methods for non-contact measurement of river discharge based on various forms of remotely sensed data. The RTK GNSS surveys were performed using a local base station and Trimble R8 and R10 receivers while wading the channel at each cross-section. Additional survey points were measured to define the locations of circular targets used as ground control points for geo-referencing the thermal image time series described in a related data release. The survey data were post-processed by performing an OPUS correction of the static observations collected by the base and adjusting all of the survey points accordingly. The survey data were exported to comma-separated text files and the resulting *.csv files contain for each point number a point ID, spatial coordinates, elevations, and a descriptive code. One of the files contains the depths calculated as the difference between surveyed water surface elevations and bed elevations at points within the channel. The other file contains ground control points.

Field-based real-time kinematic (RTK) GNSS surveys of water surface elevation and channel bed topography were collected along the Colorado River, focusing on two cross-sections from which remotely sensed data were obtained. These data were used to assess the accuracy of river bed elevations inferred from the ASTRALiTe bathymetric lidar, acquired from an unmanned aircraft system (UAS). These data sets were collected to support research focused on developing innovative methods for non-contact measurement of river discharge based on various forms of remotely sensed data. The RTK GNSS surveys were performed using a local base station and Trimble R8 and R10 receivers while wading the channel at each cross-section. The survey data were post-processed by performing an OPUS correction of the static observations collected by the base and adjusting all of the survey points accordingly. The survey data were exported to comma-separated text files and the resulting *.csv files contain for each point number a point ID, spatial coordinates, elevations, and a descriptive code. One of the fields contains the depths calculated as the difference between surveyed water surface elevations and bed elevations at points within the channel.

Field-based real-time kinematic (RTK) GNSS surveys of water surface elevation and channel bed topography were collected along the Colorado River, focusing on two cross-sections from which remotely sensed data were obtained. These data were used to assess the accuracy of river bed elevations inferred from the ASTRALiTe bathymetric lidar, acquired from an unmanned aircraft system (UAS). These data sets were collected to support research focused on developing innovative methods for non-contact measurement of river discharge based on various forms of remotely sensed data. The RTK GNSS surveys were performed using a local base station and Trimble R8 and R10 receivers while wading the channel at each cross-section. The survey data were post-processed by performing an OPUS correction of the static observations collected by the base and adjusting all of the survey points accordingly. The survey data were exported to a comma-separated text file and the resulting *.csv file contain for each point number a point ID, spatial coordinates, elevations, and a depth.

Field-based real-time kinematic (RTK) GNSS surveys of water surface elevation and channel bed topography were collected along the Colorado River, focusing on two cross-sections from which remotely sensed data were obtained. These data were used to assess the accuracy of river bed elevations inferred from the ASTRALiTe bathymetric lidar, acquired from an unmanned aircraft system (UAS). These data sets were collected to support research focused on developing innovative methods for non-contact measurement of river discharge based on various forms of remotely sensed data. The RTK GNSS surveys were performed using a local base station and Trimble R8 and R10 receivers while wading the channel at each cross-section. The survey data were post-processed by performing an OPUS correction of the static observations collected by the base and adjusting all of the survey points accordingly. The survey data were exported to a comma-separated text file and the resulting *.csv file contain for each point number a point ID, spatial coordinates, elevations, and a depth.

The U.S. Geological Survey contracted with Juniper Unmanned to conduct field tests of the ASTRALiTe bathymetric lidar system on the Blue River just upstream of its confluence with the Colorado River near Kremmling, Colorado, on October 18, 2018. The objective of this project was to assess the potential to map river bathymetry (i.e., channel bed topography) using lidar data collected from an unmanned aircraft system (UAS). The ASTRALiTe lidar instrument was mounted on a DJI Matrice 600 Pro UAS owned and operated by Juniper Unmanned. As part of the study, Juniper's pilot flew the ASTRALiTe instrument across 2 river transects (cross-stream) on the Blue River. This data release includes data delivered to the USGS by ASTRALite on November 15, 2018. The data have been parsed into separate text files for bare earth (i.e., river bed) and water surface returns for each cross-section but have not been filtered or modified in any other way.

This dataset contains survey data including wading and real-time kinematic (RTK) Global Positioning System (GPS) of water surface elevation and channel bed topography at cross section 5 (xs5) on March 20, 2018, which is adjacent to the U.S. Geological Survey (USGS) streamgage at Arkansas River at Parkdale, Colorado (USGS 07094500). The RTK Global Navigation Satellite System (GNSS) surveys were performed using a local base station associated with the streamgage and Trimble R8 ® and R10 ® receivers while wading the channel at xs5. The survey data were post-processed by performing the National Oceanic and Atmopheric Administration Online Positioning User Service (OPUS) correction of the static observations collected by the base and adjusting all the survey points accordingly. The survey data were exported to comma separated text (.csv) files, and the resulting file contains a survey point identification, spatial coordinates, elevations in meters above North American Vertical Datum of 1988, and a descriptive code for each point number. The data release also provides a channel cross-sectional area for each river stage in 0.01-meter increments derived from the survey data.

The U.S. Geological Survey contracted with Juniper Unmanned to conduct field tests of the ASTRALiTe bathymetric lidar system upstream and downstream of its confluence with the Blue River near Kremmling, Colorado, on October 18, 2018. The objective of this project was to assess the potential to map river bathymetry (i.e., channel bed topography) using lidar data collected from an unmanned aircraft system (UAS). The ASTRALiTe lidar instrument was mounted on a DJI Matrice 600 Pro UAS owned and operated by Juniper Unmanned. As part of the study, Juniper's pilot flew the ASTRALiTe instrument across 2 river transects (cross-stream) on the Blue River and 2 river transects on the Colorado River. This data release includes data delivered to the USGS by ASTRALite on November 15, 2018. The data have been parsed into separate text files for bare earth (i.e., river bed) and water surface returns for each cross-section but have not been filtered or modified in any other way.

Bathymetric and topographic surveys were collected along an approximately 24-kilometer reach of the Colorado River beginning at CO-131 State Bridge and extending downstream to the USGS streamgage located near the Colorado River Road (Catamount) bridge. The surveys were collected using real-time kinematic Global Navigation Satellite System (GNSS) receivers by USGS personnel from July 24 through July 26, 2023, using a combination of sonar and wading techniques. The wading surveys include point data that are provided as comma-delimited text files of northing, easting, elevation, and code. The sonar surveys include point data that are provided as comma-delimited text files of northing, easting, bed elevation, water-surface elevation, and depth. All spatial data are 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 13 North and are represented in units of meters.

Bathymetric and topographic surveys were collected along an approximately 5.7-kilometer reach of the Colorado River upstream from the USGS streamgage located near the Colorado River Road (Catamount) bridge. The surveys were collected using real-time kinematic Global Navigation Satellite System (GNSS) receivers by USGS personnel between May 13 through September 9, 2021, using a combination of sonar and wading techniques. The wading surveys include point data that are provided as comma-delimited text files of northing, easting, elevation, and code. The sonar surveys include point data that are provided as comma-delimited text files of northing, easting, bed elevation, water-surface elevation, and depth. All spatial data are 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 13 North and are represented in units of meters.

To support an investigation of the feasibility of measuring river bathymetry using remotely sensed data acquired from a small unmanned aircraft system (sUAS), remotely sensed bathymetry and field measurements were collected from two cross-sections on the Blue River and two cross-sections on the Colorado River near Kremmling, CO on October 17-18, 2018. The data in this release include optical measurements using the following sensors: WET Labs ECO, WET Labs ac-s, and LISST 100x. The WET Labs ECO provides measurements of turbidity and chlorophyll and colored dissolved organic matter concentration. The WET Labs ac-s provides information of the absorption and attenuation coefficients of the water sampled across a range of wavelengths. The LISST 100x provides information on the mean grain size of sediment in suspension and the concentration of suspended sediment.