Assessing the effects of urbanization on flood in Vu Gia Thu Bon river basin

Abstract

    Urbanization in the lower Vu Gia Thu Bon river basin has resulted in a change of flooding. The appearance of new urban areas such as Hoa Xuan, Cam Le, or urban areas along the Co Co river... as well as the roads including the Da Nang - Quang Ngai highway, the Hoa Phuoc - Hoa Khuong have obstructed the flow of water, and that may increase the risk of flooding in some areas. This paper has focused on simulating and assessing the extent of flooding due to the effects of urbanization in Vu Gia Thu Bon river basin. The assessments are based on 3 scenarios of large, medium and small floods (corresponding to the floods in 2009, 2016, 2020) along with topographic changes due to urbanization. The results show that the impact of urbanization has led to a significant change in the area and extent of flooding. Roads exist as dikes impeding flood flows and causing deeper flooding upstream. The results of this study will be a reference for urban development planners and the basis for making flood response measures in the future.