Multi-year deployment of a single high-frequency acoustic attenuation system for measuring fine suspended sediments in stream channels

The National Center for Physical Acoustics (NCPA) at The University of Mississippi has developed a single-frequency acoustic attenuation system (SFAAS) to monitor the concentration of suspended fine sediments in rivers and streams. The system was operated in the Goodwin Creek Watershed in Panola County, Mississippi, USA, from November 2019 to February 2023. The system collected data when the stream stage was above 0.3 m, and physical pump samples were collected concomitantly to provide calibration data. A subset of the data, comprising 14 storm events recorded over the multiyear deployment, will be presented here to demonstrate the operation of the SFAAS and its potential to aid in hydrologic research. SFAAS was able to provide high-resolution fine sediment concentration data with a stable calibration relationship for a given hardware configuration. The data were used to investigate the behavior of fine sediment concentrations in the watershed, including hysteresis in the relationship between flow rates and sediment concentrations during streamflow hydrographs and sediment rating curves that relate stream depth to transport rates.