This paper analyses whether and to what extent public decision-making, which controls land subsidence due to groundwater table lowering and its societal impacts, is organised effectively to reduce these societal impacts, and how the legal framework can be improved to achieve that.

For many subsiding coastal areas, solutions to subsidence are readily available, but difficult to implement. To facilitate decision making and implementation of measures to subsidence, a sound and shared knowlegde base is required. But how to start creating such a knowledge base? This paper presents a comprehensive, step-by-step approach to address land subsidence, illustrated by best practise examples from around the world. This 6M approach will contribute to lowering the threshold to act.

We demonstrate that the world's largest beach-ridge plain in southern Mexico was formed under an ample long-term fluvial sediment supply. The beach-ridge elevation is strongly influenced by aeolian accretion during the time when the ridge is located next to the beach. The beach-ridge elevation is negatively correlated with the progradation rate, which we relate to the variability in sediment supply to the coastal zone, reflecting decadal-scale precipitation changes within the river catchment.

The potential for subsidence of Holocene deltas due to peat compaction is mainly determined by the 3D distribution of different lithologies, and associated geotechnical properties, in the subsurface. Our study shows that sequences containing thick high-organic peat layers with no or a thin clastic overburden have the highest potential for high amounts of subsidence due to compaction. In addition, peat layers above groundwater level have high potential for subsidence due oxidation and compaction.

Deltas are increasingly under pressure from human impact and climate change. Ensuring future delta life requires sustainable management of deltas. Future Deltas is an interdisciplinary research program of Utrecht University, The Netherlands, with an international focus. It aims to understand drivers of change in deltas, predict impacts and optimize solutions and importantly contributes to the development of integrated sustainable and resilient delta management strategies.