Human interference in river deltas is massive. And despite global concerns about river delta degradation, human activity in the world’s largest deltas still intensifies. The extraction of natural resources, sediment retention by reservoirs and sea-level rise are all causes of degradation of deltas subject to tides. A team of researchers from Wageningen University, Deltares, University of Twente (Bart Vermeulen, Water Engineering and Management) and Delft University of Technology reveals the contrast between the roles of tides in natural and human-controlled deltas.