Mammoet, building consortium Sas van Vreeswijk (Besix, Heijmans, Jan de Nul) and Rijkswaterstaat recently moved the last concrete bunker by the Lek channel near Vreeswijk, the Netherlands. The operation was part of a larger project in which three bunkers and two water management structures were moved to make way for the widening of the channel. With the safe arrival of the last bunker, Mammoet’s activities have been concluded successfully.
Mammoet used a gantry positioned on Self-Propelled Modular Transporters – also known as SPMTs- to pick the bunker up and move it across 80 meters to its new location. The bunker weighed more than 750 tons. In total, Mammoet moved more than 4800 tons worth of objects for Rijkswaterstaat and Sas van Vreeswijk since the start of the project in February – that’s equal to the weight of approximately 855 elephants.
The final stage was not the easiest part of the project, despite the fact that this bunker was the lightest bunker that had to be relocated. At the end of the Second World War someone detonated a bomb in the bunker, damaging the structure. Before the bunker could be moved, the team had to build a corset around the structure to ensure that it would not be damaged further.
The three bunkers and the two water management structures are part of the Nieuwe Hollandse Waterlinie, a series of works constructed before World War II that were designed to defend the Netherlands against foreign invasions. The Nieuwe Hollandse Waterlinie has been designated as national cultural heritage in the Netherlands; it has also been nominated for inclusion on the UNESCO World Heritage list.