Sediment can be transported as suspended load (moves with the flow of the river) or as bedload (rolls along the riverbed) or can be deposited on the riverbed or bank. Sediment is naturally occurring and essential to supporting the ecological function of a water body. High sediment concentrations in rivers and streams, however, can be detrimental for a variety of reasons. Sediment must be physically measured to adequately inform water resources and sediment management decisions. USGS collects sediment samples at thousands of locations across the U.S., using nationally consistent methods. USGS sediment data are available through our national databases and data dissemination tools. This web page provides an overview of USGS's research about sediment sampling and data processing. It includes related research and a collection of data and tools (Introduction).