Author(s): Dongsu Kim; Geunsoo Son; Yougsin Roh; Suin Choi; Boseong Jeong

Linked Author(s): Dongsu Kim, Geunsoo Son, YOUNGSIN ROH

Keywords: H-ADCP Suspended Sediment Discharge Backscatter Stage Lowland

Abstract: Over recent decades, acoustic backscatter has emerged as a reliable surrogate method, offering a practical alternative to traditional techniques for continuous measurement of suspended sediment discharge. Significant theoretical and practical advancements have been made in this field. This study proposes a novel modification to the conventional approach by incorporating stage data to enhance the measurement performance of acoustic methods. By utilizing backscatter signals from discharge gaging stations equipped with Horizontal Acoustic Doppler Current Profilers (H-ADCP), we developed a site-specific, nonlinear empirical relationship between in-situ, cross-sectionally averaged suspended sediment concentration (SSC), backscatter, and stage. The proposed approach was validated using data from across 6 sites in South Korea. Comparative analysis revealed an overall accuracy around 80%, with particularly improved performance under high-flow conditions compared to models relying solely on backscatter data, which achieved accuracies below 65%. This enhancement is attributed to the inclusion of stage data, which accounts for the strong hysteresis observed between sediment discharge and stage in the low-gradient, flat terrains of the study area -- regions where traditional stage-discharge relationships often fail. Comprehensive field validation demonstrated the practicality of this improved acoustic method for continuous and real-time sediment load monitoring, particularly in lowland environments

DOI:

Year: 2025