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Strong currents induced by tidal oscillations have been overlooked in previous flood-risk assessments of the Mekong River. To discuss the potential disaster risk associated with tidal-flow intensification, this study applied ocean tidal modelling to a typical dry season when the tidal regime is predominant compared to the fluvial regime. The model can forecast tidal levels and velocities at a given time and location in the urban area of the Mekong Delta, which is characterized by many tributaries, channels, and low-lying lands, in addition to the main stream of the Mekong River. Numerical simulations revealed that a rapid flow, which could exceed 1 m/s in both the ebb and flood tidal phases, likely occurred along the tributary. Although this study only focused on the tidal regime, such locally intensified flows can be further amplified by a high river discharge or storm surge, having potentially dangerous consequences, such as difficulties in handling ships and small ships being capsized.
Can Tho city, ebb tide, flood tide, flow intensification, ocean tidal modelling, rapid flow, the Mekong Delta, the Mekong River, tributary
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