Deltas are complex systems of rivers discharging into the sea, where fresh and saltwater mix with each other, high and low tides are alternating, new land is created by sediment deposits and, at the same time, currents and waves take care for the erosion of land.

These dynamics and variations result in rich natural environments. At the same time, deltas are attractive areas for urban and economic development. The largest cities and the most explosive growth of cities worldwide can be found in delta regions, which leads to conflicts with the natural system of the delta.

Most delta regions show a dramatic decline in the natural conditions of the delta and an increase in the vulnerability of urbanized areas in terms of flood risk, drought, salination, and freshwater shortage.

Problems of urbanized delta regions are accelerating because of climate change. Adaptation of delta regions is necessary to be prepared for increasing sea-level rise and increasing peak discharges by rivers.
Deltastad focuses on the design and development of urban configurations, which can contribute to a new, adaptive balance between natural systems and urban development.