Design of a sensor to estimate suspended sediment transport in situ using the measurements of water velocity, suspended sediment concentration and depth.

— The sediment transport plays a major role in every aquatic ecosystem. However, the lack of instruments to monitor this process has been an obstacle to understanding its effects. We present the design of a single sensor built to measure water velocity, suspended sediment concentration and depth in situ , and how to associate the three variables to estimate and analyse sediment transport. During the laboratory calibrations, the developed instrument presented a resolution from 0.001 g/L to 0.1 g/L in the 0–12 g/L range for the measurement of suspended sediment concentration and 0.05 m/s resolution for 0–0.5 m/s range and 0.001 m/s resolution for 0.5–1 m/s range for the measurement of water velocity. The device was deployed for 6 days in an estuarine area with high sediment dynamics to evaluate its performance. During the field experiment, the sensor successfully measured the tidal cycles and consequent change of flow directions, and the suspended sediment concentration in the area. These measurements allowed to estimate water discharge and sediment transport rates during the different phases of tides, and the daily total volume of water and total amount of sediment passing through the estuary. • Development of an instrument for in-situ continuous monitoring of sediment transport. • Methodology to calibrate the sensor for flow velocity and sediment concentration. • Field experiment in an estuarine environment to measure hydraulic dynamics. • Measurement of the stream flow inversion during high and low tides. • Estimation of water discharge and sediment transport rate. [ABSTRACT FROM AUTHOR]