Bathymetry of the Similkameen River Above Enloe Dam Near Oroville, Washington

This data release provides the results of the bathymetric survey of the Similkameen River directly above Enloe Dam which took place over three days in late September 2020. The bathymetric survey was completed to enable an instrument-based estimate of the volume of legacy sediment impounded behind Enloe Dam. A shoreline water level survey collected points at the river?s edge using Trimble R8 GNSS Receivers. Safety requirements directly upstream of the dam made a ground survey infeasible, thus shoreline points were inferred from the National Agricultural Imagery Program (NAIP) 2015 imagery corrected to Okanogan County lidar. The study area polygon was constructed from the shoreline points with a 0.5m buffer applied. Bathymetry was collected using an Acoustic Doppler Current Profiler (ADCP) which measured the depth to sediment below water surface. All ADCP data were post-processed using the USGS Velocity Mapping Toolbox. The surveyed shoreline points were assigned a bathymetric depth value of zero. The bathymetric surface was interpolated to 3m resolution using Spline Interpolation with Barriers in ArcGIS Pro 2.5.0, where the barrier was set as the survey_area polygon.