Analysis of Flow Phenomena in River Ganga between Buxar and Farakka

Abstract

This study investigates the hydrodynamic and morphodynamic behavior of the Ganga River along a critical 400 km stretch between Buxar and Farakka, a region prone to severe flooding, sedimentation, and channel instability. The primary objective is to analyze seasonal flow patterns, sediment transport mechanisms, and flood propagation dynamics using a combination of field measurements, remote sensing data, and hydraulic modeling tools. Hydrological and sediment data from the Central Water Commission (CWC), supported by satellite imagery and cross-sectional surveys, formed the basis of the analysis. Velocity measurements using Acoustic Doppler Velocimeters (ADV), sediment sampling, and bathymetric profiling were conducted at key locations. Computational modeling was performed using HEC-RAS and Delft3D to simulate water levels, velocity fields, sediment deposition patterns, and flood extents under varying discharge scenarios. The results highlight substantial seasonal variation in discharge and sediment load, with monsoon periods marked by high suspended sediment concentrations and extensive lateral channel migration. Erosion-prone zones were identified near Bhagalpur and Sultanganj, while depositional features were prominent downstream of major confluences. The models demonstrated strong agreement with observed data, indicating their applicability for predictive flood and sediment management. These findings have significant implications for river engineering, flood mitigation planning, and sediment control in one of India's most densely populated river corridors. The study contributes to a deeper understanding of the Ganga’s dynamics and supports evidence-based policy and infrastructure design.