Morphological Changes in Deltaic Rivers: A Case Study on the Meghna, Payra and Karnaphuli Rivers in the Coastal Region of Bangladesh

Abstract

Understanding river dynamics is vital for effective coastal management and conservation. Bangladesh lies mainly in the Bengal Basin, where the major rivers flow into the Bay of Bengal via the Meghna estuary. This study examines riverbank changes along the Meghna, Payra, and Karnaphuli rivers from 1999 to 2022, using satellite imagery to track erosion and accretion patterns across coastal zones. A 50-kilometer-wide area along each river reveals significant bank dynamics. The Karnaphuli River experienced notable left bank erosion of 41.06 meters between 2019 and 2022. The Meghna River underwent drastic changes, with 1561.34 meters of left bank erosion from 1999 to 2004. The Payra River showed right bank erosion of 95.13 meters over the same period. High-resolution satellite imagery and GIS processing quantified land changes and sinuosity indices, highlighting the rivers' meandering patterns. The findings underscore the dynamic nature of these coastal rivers, shaped by sediment transport, water flow, and human activities. Continuous monitoring and research are essential for understanding river dynamics, managing resources, and mitigating erosion and accretion impacts on vulnerable coastal regions.

The Dhaka University Journal of Earth and Environmental Sciences, Vol. 14(1), 2025, P 87-100