Synthesis of drainage characteristics, water resources and sediment supply of the Bengal basin

Abstract

This systematic review attempts to delineate a synthesis of the main drainage characteristics of the Bengal basin through the study of historical data, old maps, reports, records, satellite images, water and sediment discharge, etc. In doing so, especial emphasize is given on the changing scenery of the river courses (paleo-present), sediment supply and water resources as well as downstream impact on socio-economy and valuable landforms (e.g., agricultural, settlement, urban, sub-urban, municipality, industry, forest, etc.). Nevertheless, impacts on biodiversity, ecosystem, water discharge and suspended sediment transport to deltas, eco-environment, human-life etcetera were also considered in evaluating the drainage characteristics. With continuing earlier custom, till now, human lives, valuable landforms and national economy have continuously been negatively affected by the rapid and frequently changing flow path of the largest rivers (Padma, Jamuna, Meghna) with the consequential river bank erosion. Furthermore, the polders, embankments, river training, and upstream barrages/dams lead to cause and enhance undesired channel siltation, land subsidence, severe erosion, sudden catastrophic floods, water logging, salinity, etc., and also hinder sediment transportation/delivery and water discharge to the basin. Finally, it has a huge impact on the basin's human-life, landforms, biodiversity, ecosystem, eco-environment, etc.

Keywords

• Brahmaputra-jamuna river
• Ganges-padma river
• Meghna estuary
• River discharge
• Climate fluctuation
• GBM delta