Intertidal areas – the lands flooding and drying during the tidal cycle – in river deltas disappear because of land reclamation and sea level rise. Understanding the consequences is crucial because intertidal areas influence the behaviour of the tide and, as a result, the shape and composition (morphology) of the estuary. Therefore, understanding the interaction between processes on the shoals and in the channels is necessary to anticipate future changes. This study aims to improve this conceptual understanding through a combination of ‘realistic’ and ‘schematised’ numerical modelling approaches, supported by hydrographic observations to be taken in multiple field campaigns in the river-influenced Ganges-Brahmaputra-Meghna delta.