Field measurements of flow velocity were acquired from a reach of the Tanana River near Nenana, Alaska, July 24, 2019, to support research on estimating surface flow velocities from remotely sensed data via particle image velocimetry (PIV). The 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. This data release provides depth-averaged flow velocities derived from the raw ADCP data using the TRDI WinRiver II processing software. The spatial location of each velocity 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 consists of a single comma-delimited (*.csv) text file with four columns: X (m), Y (m), U (m/s), and V (m/s). The first two columns are the easting and northing spatial coordinates, respectively, and the third and fourth columns contain the x and y (east and north) components of the depth-averaged velocity vectors, respectively. The units of the coordinates are meters and the units of the depth-averaged velocities are meters per second. This field-based data set was used to assess the accuracy of remotely sensed estimates of surface flow velocity derived from optical image sequences via PIV.