Riverbank migration and island dynamics at the Padma-Meghna confluence: A multi-temporal analysis of erosion and deposition patterns

The Padma and Meghna rivers, both alluvial, converge at Chandpur, forming the Lower Meghna and channeling water from the GBM basins toward the Bay of Bengal. Annual erosion at this confluence displaces riverbanks, degrades land, and displaces inhabitants, impacting public infrastructure. This study examines riverbank migration and island dynamics near the confluence, focusing on erosion and deposition patterns using Landsat images (1980–2024). Results reveal that combined banks lost 35.83 m/yr but gained 54.23 m/yr, with the Padma’s right bank most erosion-prone (77.29 m/yr). Additionally, the right bank erodes more significantly, moving southeast, while the left bank gradually shifts northeast. Larger islands show greater stability during floods compared to smaller, dynamic ones. This research offers new insights into the erosion-deposition processes and riverbank migration at the Padma-Meghna confluence. • Padma-Meghna confluence faces significant erosion near Chandpur. • Landsat images (1980-2024) analyzed for riverbank and island changes. • Padma right bank erodes fastest (77.29 m/yr), shifting southeast over time. • Combined banks lost 35.83 m/yr but gained 54.23 m/yr, stabilizing post-2006. • Larger islands are stable; smaller islands change.