Evolution of river course and morphometric features of the River Ganga: A case study of up and downstream of Farakka Barrage

Abstract

River channel shifting in the deltaic regime is an unabated occurrence. Channel shifting has become one of the concerns as it influences land use/land cover along the riverbank in various ways. For the management of the river, it is indispensable to study the pattern of river course change both in qualitative and quantitative methods. This study is an attempt to understand the pattern of shifting and to quantify erosion and deposition of the river Ganga at upstream and downstream of Farakka Barrage during 1794–2017. The study has been carried out by using various historical maps, aerial photographs, satellite imagery, and remote sensing and GIS technique to understand the dynamic of the river. Over 223 years period shifting of the river accentuates the remarkable oscillation of the river. Perimeter of the river is determined to understand the area covered by the river course in the study area. To evaluate the meandering of the river sinuosity of the river has been computed in this study. The amount of erosion and deposition was calculated in this study by using ArcGIS 10.6. The study found a higher amount of erosion at the east bank where Manikchak, Kaliachak II and Kaliachak III blocks are situated between 1965 and 2017. At the west bank of the river, especially the Rajmahal block, the occurrence of deposition was remarkable during the same period.