Abstract

The study focuses on simulating the bottom morphology under the influence of river currents and tides in Hau Estuary in Soc Trang province during the flood season according to the scenarios in 2017, sea level rise of 73 cm and reducing sediment by using MIKE 21FM. The results show that the erosion and accretion processes are consistent with the velocity distribution of the flow; the accretion trend prevailed over the erosion trend in Hau Estuary. The maximum velocity at the islet upstream was distributed in the river bed with the maximum erosion level of 0.3m. The strong erosion areas were concentrated on the river bed at the banks of the islet with the largest level being 0.13m while the accreation area along the Dinh An estuary was a level of 0.24 m. For the scenario of sea level rise and reducing sediment, the trends of accretion and erosion did not change much compared to the scenario in 2017. With sea level rise scenario, the value of erosion will be decreased, however, deposition value will be recorded a decrease in the estuary. Regarding the reducing sediment scenario, the islet upstream will be eroded more than scenario in 2017, on contrary, the accretion of the river mouth will be reduced.