Confluence Dynamic
Understanding of the dynamic of the confluence is very important for proper planning and management of the river. It not only change the bifurcation of the Lower Meghna River at the downstream but also it altered the shifting of the banklines along its both banks. This section provides the dynamic of the Lower Meghna River due to the confluence dynamic.
Confluence Dynamic of Lower Meghna River
Banklines of the Padma-Meghna confluence area in the last 37 years tells that the Lower Meghna River shifted towards both east and west during the period 1984-2021. The river has shifted approximately by 5.3 km (maximum) towards west along the right bank while it is only 3.0 km along the left bank towards east. But development of the changes in shorter period would give clearer picture. Decadal analysis suggests that the river shifted roughly 2.6 km to west during the period 1984-1996 though it was nearby to 2.0 km to east.
During 1996-2010, bankline shifted by 4.3 km and 2.2 km along the right bank and the left bank respectively. The shifting of the bankline is still the continuous process in the recent decade in 2010-2021. But the intensity is less. About 1.2 km of riverbank shifting was observed along the right bank towards west side while no shifting was perceived along the left bank in the study area. Probably the construction of the river training works along the left bank from the confluence point to the downstream certainly limited the shifting of the river to east.
Besides, it is quite obvious that the alteration of the confluence point has significant role in shifting of the river course although there is no direct relation.