Bathymetry of Blackfoot Reservoir, Caribou County, Idaho, 2011

The USGS, in cooperation with the Shoshone-Bannock Tribes, surveyed the bathymetry of Blackfoot Reservoir in 2011 to determine temporal changes due to sedimentation and other factors, and to improve the overall accuracy of the stage-capacity table. Bathymetric surveys of high accuracy and resolution are possible through advances in instrumentation, notably a multibeam echosounder (MBES). An MBES coupled with real-time kinematic global positioning systems (RTK-GPS) has advantages over traditional techniques for surveying reservoir bathymetry, such as single-beam echosounders, acoustic Doppler profilers, or soundings, because they can provide more coverage of the reservoir bed and real-time data corrections. The topography (above-water) of the reservoir, which could not be measured with the MBES, was surveyed by Horizons, Inc., in 2000 using terrestrial light detection and ranging (LiDAR), and verified in selected areas by USGS in 2011 using RTK-GPS surveying equipment.