This study investigates sediment dynamics at the diversion inlet and service spillway of the Springbank Off-Stream Reservoir flood diversion structure on the Elbow River, Alberta, using the FLOW-3D HYDRO software. By reproducing experimental observation obtained from a corresponding physical model, it focuses on sediment erosion and deposition patterns resulting from both bedload and suspended sediment transport processes, evaluating the numerical capabilities and limitations of the software. The simulations account for material-specific properties of the sediment, including grain size, density, critical shear stress, and angle of repose, to accurately represent sediment dynamics. The results show that the model employed accurately predicts the overall deposition patterns formed by flow conditions and suspended sediment settling. By conducting sensitivity analysis for key sediment transport parameters, this study provides insights on the best practices for modelling sediment transport processes in the selected case study with FLOW-3D HYDRO. Overall, it demonstrates the capability of its empirical models to replicate sediment erosion and deposition observed