Hungry rivers—Insights from a sediment budget

Abstract A river is considered supply limited, or hungry, when its capacity to transport sediment (strongly) exceeds the supply of sediment. Common consequences include erosion of bed material and channel incision, as observed in the heavily engineered river Meuse in the Netherlands, where these processes have contributed to the formation of scour holes. This study establishes a sediment budget for the Dutch part of the river Meuse, aiming to better understand the drivers of channel incision, and to assess the potential of mitigation by removing bank protection. We used multibeam data to track riverbed elevation changes, laser altimetry data describing banks and floodplains, a detailed dredging and nourishment database, recent bed material samples and hydrodynamic modelling results to set up a sediment budget for a 250 km stretch of the river from 2011 to 2019. Our findings reveal that in the Dutch Meuse River, annual sediment extraction volumes frequently exceed natural sediment loads several times. Rather than reduced inputs from tributaries, sediment mining and barrages reducing sediment connectivity control the hunger of the river. Removing bank protection alleviates supply‐limited conditions, at least temporarily. The comprehensive sediment budget obtained in this study offers a knowledge base for sustainable river management, highlighting the importance of international collaboration in sediment management efforts.