Sedimentation Analysis of Kabul River by Using HEC-RAS

Rivers are crucial sources of water with multi-faceted applications, and effective river engineering involves addressing sedimentation and erosion concerns. The Kabul River, owing to its strategic significance and environmental implications, garners significant attention in Afghanistan. This stems from its role in water project design, existing reservoirs, and urban and industrial water supply in Kabul. Notably, the Kabul River bears the highest sediment loads among Afghanistan’s rivers, leading to pronounced sedimentation issues in Kabul city. This study employs the Hydrologic Engineering Centre River Analysis System (HEC-RAS) model to comprehensively assess hydrological parameters and sedimentation processes. The analysis encompasses variations in transverse and longitudinal profiles, fluctuations in velocity and shear stress, changes in mass distribution, alterations in bed levels, evaluations of total sediment, erosion dynamics, and deposition patterns. Focusing on a 40-km stretch, spanning from the Pul-i-Surkh station in Maidan Province to the Tangi-Gharo station in Kabul City, the study also accounts for contributions from branch rivers and streams, augmenting sediment volumes. Urbanization, non-standard constructions near the river, and the demand for enhanced sanitation infrastructure contribute to heightened sedimentation. The river’s intermediate segment exhibits a variable slope, intensifying sediment-related challenges. Spanning from January 2016 to June 2020, this research period encapsulates diverse conditions in Kabul City and the intricate dynamics of sediment transport, erosion, and sedimentation processes. The study contributes a comprehensive framework to comprehend Kabul City’s conditions and the complex consequences of sediment-related processes. © The Institution of Engineers (India) 2023.