Regional Hydraulic Geometry of Banger River Related to Sediment Prediction and River Morphology Stability

Sandhi Akhmad Juliadi; Indratmo Soekarno; Eka Oktariyanto Nugroho; Widyaningtias Widyaningtias

Sandhi Akhmad Juliadi 1Master Study Program of Water Resources Management, Civil Engineering Study Program, Faculty of Civil and Environmental Engineering, Bandung Institute of Technology, Jalan Ganesa 10, Bandung 40132, Indonesia
Indratmo Soekarno Water Resources Engineering Research Group, Civil Engineering Study Program, Faculty of Civil Engineering and Environmental, Bandung Institute of Technology, Jalan Ganesa 10, Bandung 40132, Indonesia
Eka Oktariyanto Nugroho Water Resources Engineering Research Group, Civil Engineering Study Program, Faculty of Civil Engineering and Environmental, Bandung Institute of Technology, Jalan Ganesa 10, Bandung 40132, Indonesia
Widyaningtias Widyaningtias Water Resources Engineering Research Group, Civil Engineering Study Program, Faculty of Civil Engineering and Environmental, Bandung Institute of Technology, Jalan Ganesa 10, Bandung 40132, Indonesia

Keywords: banger, flood, morphology, geometry, sediment

Abstract

Pekalongan City is located in the lowlands which has a very gentle slope of the land surface. In some northern areas, most of the land surface is below sea level, making it difficult for water to flow into the sea because it is held back by water from the sea (rob). In this paper an analysis will be carried out regarding the distribution of floods and see how the regional hydraulic geometry occurs in the Banger River. Furthermore, this research aims to examine the conditions of sediment transport and the stability of river morphology that occur in the Banger River. Flood modeling and sediment transport analysis in this study were conducted using HEC-RAS software. The results of this research indicate that during a 2-year return period flood, approximately 400.14 hectares of area, mainly in downstream areas will be inundated due to the river's morphological instability related to its width, depth, and slope. This study is highly valuable because the stability of the river regime, which may contribute to flood occurrences, is often overlooked in river management planning

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