Author(s): Rezar Lleshi; Slaven Conevski; Massimo Guerrero; Nils Ruther; Agim Lazareni; Tor Haakon Bakken; Siri Stokseth

Linked Author(s):

Keywords: Reservoir sedimentation; Sediment transport modelling (1D); Sediments and hydropower; Sustainable sediment management

Abstract: Sediment transport and deposition pose significant challenges for reservoir management, impacting both hydropower operations and environmental stability. This study evaluates a long-term sediment modeling approach using a 1D HEC-RAS model, incorporating sensitivity analysis on the particle size distribution (PSD), sediment densities, and cohesive sediment parameters to simulate deposition patterns. The results indicate that a 10% increase in PSD coarseness and sediment density, along with higher critical shear stress (τc), produced the most accurate match with observed data. While the total deposited volumes closely aligned with measurements, localized deviations suggest the influence of turbidity currents and other complex transport processes. Despite the model’s effectiveness, data limitations -- such as the absence of inflowing sediment concentration measurements -- highlight the need for improved calibration. Frequent bathymetric surveys and sediment characterization efforts are essential for refining input parameters and enhancing predictive accuracy. Future work should focus on optimizing 1D models using advanced calibration techniques, integrating variable PSD inputs over time and space, and incorporating turbidity currents into the modeling framework

DOI: https://doi.org/10.64697/978-90-835589-7-4_41WC-P1941-cd

Year: 2025