Rotterdam

A City and a Mainport on the Edge of a Delta

Abstract

This paper can be seen as the overall introduction in which the Rotterdam Rijnmond case study region and its spatial and flood risk challenge are introduced. It describes the strong historical relation between flood risk management interventions and the spatial development of the region. The region is protected against floods by an extensive system of (sea)barriers and dike-rings. Positioned on the edge of the Rhine-Meuse delta, the region developed as a port area and is part of the so-called Randstad area: the most densified area of the Netherlands.

Due to climate change, increasing sea levels and peak river discharges are expected in the future, resulting in an increased flood risk. In order to address this future flood risk challenge, the second Delta Committee was established - the first Delta Committee was established after the 1953 flood that flooded part of the Netherlands. This Delta Committee develops regional strategies for flood risk reduction for the long-term period, up to 2100. As part of the strategy development process, four conceptual regional flood risk reduction strategies are developed, which can be perceived as cornerstones of the playing field of possible flood risk reduction strategies for the region.

Those cornerstone strategies vary from the complete damming of the delta (thus lowering the extreme water levels behind the barrier) to opening up the delta and dealing with the expectedly high water levels by elevating the region’s dike-rings. The different cornerstones offer different potentials and threats for the spatial development of the region. In addition, at a local scale, the different cornerstones impact the spatial quality of the dike zones and flood plains in different ways.

This strong relation between the flood risk management interventions and spatial composition and quality of the region supports the urgency of approaching the future flood risk reduction task in a comprehensive way.