Author(s): Ayuko Hirani Saleh; Akira Tai; Mukhsan Putra Hatta; Shinichiro Yano

Linked Author(s): Ayuko Hirani Saleh, Akira Tai, Shinichiro Yano

Keywords: Climate change; Extreme Rainfall; Flood; Jeneberang River Basin

Abstract: Climate change will have a substantial effect on the water cycle, leading to severe environmental issues and disasters in tropical river basins. An example, the river basins in South Sulawesi Island, Indonesia, where the lowland areas are mostly composed of paddy fields and farmland, which are wetland environments initially inundated by flooding from rivers. Consequently, projecting the extent of inundation due to flooding events is considered important for river basin management. The aim of this study is to investigate the trigger of flood disaster and identify the inundation area in the Jeneberang River Basin. In the present paper, the last model was used for hydrodynamic simulation in the area. The flood simulation for the Jeneberang River was carried out using the modelling tool Nays2DFlood, which integrates 2-Dimensional plane flow. The river discharge was determined by a single input point and the average rainfall data from the six rainfall gauges. The results indicate continuous rainfall at the time, which is the main trigger for flooding in the Jeneberang River Basin. The heavy rainfall recorded 285 mm/day at three rainfall stations. Similarly, Jeneberang river basin areas were also affected by land use changes. It was noted that there has been a change in land use for residential development of up to 2% of the basin areas in 7 years (2012-2018) along the Jeneberang river basin. In addition, land use changes occurred in the upper area, which was formerly a forest area but has been turned into farmland due to some of the local residents' working as farmers. The simulated flood inundation detected the highest flood depth up to 2 meters, which inundated some areas and led to the loss of life. It is understood from this study that the Jeneberang River basin is susceptible to flooding. The outcome of this study provides an assessment of flood susceptible areas which can be used as a reference for flood risk management, prevention, and reduction of natural disasters in the area.

DOI: https://doi.org/10.3850/IAHR-39WC252171192022843

Year: 2022