The Ramspol surge barrier is the final project in the framework of the Deltawet Grote Rivieren (the ‘Delta Act for Large Rivers’, notably the Rhine and the Maas, which nationalized Dutch flood management projects and provided for the closure of estuarine inlets: translator’s note). If there is high water that is further driven up by the wind then the dam seals the mouth of the Zwarte Meer (‘Black Lake’), to protect it from the surging water level of the IJsselmeer lake.
In view of the consequences for the landscape, as well as ecological considerations, a decision was taken to construct a new dike instead of raising and reinforcing the existing dikes.
It is an innovative type of storm surge barrier. In case of rising water levels, the bellows of the inflatable dike are filled with water and air. The bellows is composed of three sections, each 80 metres long, making it the biggest dike of its kind in the world. In its normal state the bellows lies on the riverbed. With extremely high water on the IJsselmeer the ‘bag’ of rubber sheeting is filled to a height of eight metres and a width of 13 metres.
The task was to execute the architectural design and landscaping of the complex. The construction associated with the dam was designed as a contemporary addition to the landscape, respecting the existing landscape elements. The dike with the control buildings and the elements of the dam on and around the water manifests itself as a new linear and technological element, projected onto the much older and naturally capricious landscape.
Two almost identical buildings mirror each other at the ends of the dam. Both buildings stand on a concrete abutment at the end of a grass-covered dike. The elliptical section of the bellows is reflected in the design of the control building.
The buildings are characterized by five conical, arched shells of stainless steel, which are nested like the armour plating of a lobster. The shells increase in size towards the water, so that the structures open out towards the view. The upper section of the control buildings overlooking the water is transparent. The buildings are enclosed on the side overlooking the dike. For passers-by, the only fleeting glimpse of the interior is via the glass entrance. The diffuse reflection of the surroundings and the sky in the stainless steel helps the integration of the buildings in the surrounding landscape.
There are shell-like, prefabricated concrete caps in line with the abutments in order to protect the clamps for the rubber sheeting of the inflatable bellows. The form of the caps mirrors that of the bellows when inflated.