Acoustic Doppler Current Profiler (ADCP) field measurements of flow depth and velocity from the Tanana River, Alaska, collected on August 18, 2021

Field measurements of depth-averaged flow velocity and water depth were acquired from the Tanana River near Nenana, Alaska, August 18, 2021, to support research on estimating surface flow velocities and water depths from remotely sensed data. The depth and velocity measurements included in this data release were obtained using a TRDI RiverRay acoustic Doppler current profiler (ADCP) deployed from a boat with an outboard motor. These data were collected along 8 cross-sections on the Tanana River; two passes across the channel were made at each cross-section. This data release provides depth-averaged flow velocities and total flow depths derived from the raw ADCP data using the TRDI WinRiver II processing software. The WinRiver II output was imported into the USGS Velocity Mapping Toolbox (VMT), which was used to project measurements made along each pass back and forth across the channel onto a common mean cross-section and smooth the data. VMT and custom MATLAB functions were then used to generate text files with projected spatial coordinates, depth-averaged velocity vector components in the east and north directions, and flow depths. The spatial location of each measurement was obtained using a differential GPS included as part of the RiverRay instrument package. The map projection and datum for these data are UTM Zone 6 N and NAD 83, respectively. This data release includes a comma-delimited (*.csv) text file consists of six columns: Cross_Section_ID, UTM_East_m, UTM_North_m, Velocity_East_Component_m_per_s, Velocity_North_Component_m_per_s, and Depth_m. The first column is an integer identifying the cross section, the next two columns are the easting and northing spatial coordinates, respectively, the fourth column is the east component of the the depth-averaged velocity magnitude in meters per second, the fifth column is the north component of the the depth-averaged velocity magnitude in meters per second, and the sixth column is the water depth in meters. This field-based data set was used to assess the accuracy of remotely sensed estimates of surface flow velocities and water depths derived from fixed wing aircraft-based optical image sequences.