Acoustic based assessment of cross-sectional concentration inhomogeneity at a suspended sediment monitoring station in a large river

Abstract Establishing and operating a harmonized sediment monitoring system along large rivers such as the Danube River is challenging international task. As an element of system, new site with state-of-the-art instrumentation currently under development in Upper-Hungarian section River. The station will consist near-bank optical backscatter sensor horizontal acoustic Doppler current profiler (H-ADCP). previous studies showed, suspended concentration (SSC) that continuously measured sensors can significantly enhance temporal resolution transport monitoring. However, plumes from tributary inflows upstream alter detected concentrations, eventually biasing load estimation. Such influence likely cross-section planned station, therefore, thorough preliminary analysis cross-sectional variation SSC was performed, based on expeditionary measurement campaigns. Between 2018 2021 24 campaigns were carried out at different hydrological regimes, where physical samplings together fixed moving boat ADCP measurements performed. variability its estimations assessed measurements, after calibrating signal more than 500 samples. Based results, we identified patterns which apparently governed by: (i) actual situation considering both main river tributary, (ii) local morphology. our findings, suggested correction method accounts for above effects, using be reliably converted into total load.