Subsidence and sea level rise threaten many deltas. To ensure liveability in these densely populated areas, it is important to understand the behaviour of these systems. Bedforms are common features in rivers and estuaries in deltaic regions, and influence the water level and sediment transport, by inducing hydraulic roughness; a measure of the amount of friction water experiences. This study aims to determine the dynamics of bedforms in different estuarine systems and relate this to hydraulic roughness. This will be achieved by analysis of field data from the river bed and river flow, and will be complemented with laboratory research.