Delineating lateral channel migration and risk zones of Ichamati River, West Bengal, India

Monitoring river progression during different time span is required to understand the present and future behavior of a river. Ichamati River is a key river of North 24 Parganas District in West Bengal, and is a connecting link between 'Nadia Group of Rivers' and Sundarbans. The Ichamati River is highly susceptible to severe bank migration due to its channel geometry and the local land use. This study was done by mapping the river channel and delineating the migration patterns of its meanders. Quantification of river channel planform was done through analysis of temporal data in GIS environment. Periodic rates of fluctuation of channel ranged from -84 to 238% of the recorded shorter periodic trends in bends which had high Radius of Curvature (R-c). Significant changes have occurred on the eastern part while fewer changes occurred along the middle part close to the Baduria Town. Risk zone area delineation due to bank erosion has also been attempted. The study underlines the fact that scrutinizing erosion process can help us better comprehend the reasons, formulate forecasts, and chart how to execute preventive and recuperative approaches. (C) 2019 Elsevier Ltd. All rights reserved.