Riverbank Erosion and Channel Morphology

This chapter focuses on the impact of bank erosion on channel planforms and channel morphology. The planform changes include meandering and braiding. In a river stretch with a high rate of bank erosion, meandering and braiding of channels are the most common features. Hence, this chapter unfolds how bank erosion is associated with the channel pattern. The progressive development of a channel from straight to meandering and meandering to braided is addressed in the context of bank erosion. Fluvial entrainment and bank erosion add sediments to the river and alter the functioning of the fluvial system. The rivers of the Bengal Delta especially the lower stretches are frequented by the emergence of channel bars (mid and point). Therefore, logically the erosion-accretion processes have been examined in the context of char development. Thus, channel braiding and anastomosis have also been examined in light of bank erosion and excess sediment loads. Moreover, the changes in the width-depth ratio, width index, depth index, and dynamics of channel asymmetry symptomize bank erosion. These variables are dealt with in-depth for the major rivers of the study area.