Sediment transport in the lower Snake and Clearwater River Basins, Idaho and Washington, 2008–11

Abstract

This report documents findings based on sediment data collected by the United States Geological Survey (USGS) in the lower Snake and Clearwater River Basins from 2008 through 2011. The purpose of this report is to provide information that improves the scientific understanding of the processes affecting sediment generation in the lower Snake and Clearwater River Basins and river hydrodynamics controlling sediment transport, deposition, and retention in Lower Granite Reservoir and downstream in the Snake River. The report provides suspended sediment and bedload data to (1) identify the dominant subbasins contributing sediment to Lower Granite Reservoir, (2) evaluate sediment transport in the Clearwater and lower Snake River Basins, and (3) quantify transport of sediment to Lower Granite Reservoir. Additionally, data collected using acoustic Doppler velocity meters (ADVMs) is summarized and compared with conventionally acquired sediment data to evaluate the efficacy of estimating suspended‑sediment concentration (SSC) continuously by means of acoustic surrogates.