From nature conservation towards restoration of estuarine dynamics in the heavily modified Rhine-Meuse estuary, The Netherlands.
Storm, C.; van der Velden, J. A.; Kuijpers, J. W. M.
The Rhine-Meuse estuary is potentially one of the most important wetland areas in the Netherlands, but since the Middle Ages it has been subjected to excessive influence from human activities. Marshes have been converted into agricultural land, harbours, and cities. Estuarine dynamics were minimized for storm surge protection, and the estuary became heavily polluted. Since the late seventies water quality has improved, and therefore habitat rehabilitation has become effective. To achieve a healthier ecosystem a program of remedial action has been launched. Some elements, such as the protection of valuable wetlands against erosion, have been almost completely realized. In the nineties, the management strategy changed direction towards the restoration and enhancement of ecological functions, rather than being confined exclusively to the protection of existing values. The main issue became the restoration of estuarine processes. This can be achieved through the modification and management of the Haringvliet sluices, and by creating conditions that assist ecological rehabilitation. Greater emphasis is given to the restoration of tidal and river dynamics in polders by replacing the dike further inland. These projects are in many respects different from the nature conservation works, and therefore require a different, more process oriented approach. The main challenge is to find a compromise between ecological values and multiple human uses and demands upon the water system, such as safety from flooding, recreational use, agriculture, and housing projects on the waterfronts.