Study of sediment transport distribution pattern after normalization in the Majalaya Area, Citarum River

Abstract

Majalaya area in West Java, Indonesia, is prone to extreme rainfall events that cause flooding of the Citarum River. The river flows through the area, naturally containing sediments from erosion upstream that disturb the river balance. Some flat areas of the river retain sediments and cause excessive accumulation, resulting in changing the storage capacity of the river. The accumulation disrupts the flow of water and causes flooding in the area. To mitigate this problem, the River Basin Authority has implemented sediment dredging and river normalization with a total length of 5.4 km in 2020, successfully preventing flooding in the first year. However, subsequent floods that affected more than 7,000 people return to occur due to changes in land use, human activities, and unmanaged erosion upstream. This study examines the sediment accumulation pre-2020, immediately after the normalization efforts 2020, and the current sediment profile 2022. The result provides an overview of the river's morphology, sediment distribution patterns, and potential future profiles. The research results can be used to evaluate flood management risk in the area, including the compound flood risk caused by continuous sedimentation and climate change, e.g., heavier and longer rainfall.