Δ-ENIGMA: The Dutch Delta on the Intensive-Care monitor Deltas and coastal plains are attractive places to live: fertile, flat, open to the sea. These lowlands are, however, also vulnerable to climate-change and sea-level rise. To better predict how deltas develop in the future we need a thorough understanding of how organisms, currents, waves, water&sand discharge shape the delta-landscape. This so-called biogeomorphology lies at the heart of Δ-ENIGMA, which provides infrastructure for intensive observational and experimental research of the Dutch Delta. This will improve our ability to predict future development, and help us live on happily in a changing Delta.

Managed deltas are social-ecological systems that provide flood- and food security. However, land subsidence and sea level rise render deltas vulnerable to flooding, the impact of which is exacerbated by population growth and urbanization. These stresses affect institutional requirements for delta systems. Polders can mitigate these threats by offering flood protection and increased food production. In Bangladesh, polders increased yields, but at the delta level, they affected rivers drainage capacity and siltation. At the polder level, they caused land subsidence, and waterlogging. In response, in 1990, local people themselves breached dikes of the Dakatia beel polder, to re-allow tidal flows. This eroded silt from the tidal channels enabling drainage of waterlogged areas, and re-allowed sedimentation inside polders, raising soil surfaces and fertility. Ever since, Tidal River Management has been experimented with, however, its full potential has not yet been reached due to fundamental knowledge gaps regarding physical and institutional boundary conditions. Rather than being an obstacle, sediments provide a high potential for a Building with Nature approach, which works with rather than against the forces of nature. This project builds on this notion and seeks to explore the potential of Living Polders that accrete along with rising water levels. The project offers comprehension of integrated, coevolving physical and institutional processes across delta- and polder scales. Subsequently, it provides pathways to optimization through a Decision Support System for dynamic polder management and associated business cases. Project outcomes are evaluated for application elsewhere, thus offering business opportunities for the Dutch water sector.