The Willem van Oranje railway tunnel runs underneath Windmill de Roos and the Bagijnetoren Tower. But how do you make something like this? You cannot just dig a tunnel under these monuments. And they should not collapse either by vibrations or deformations of the subsoil during the construction of the tunnel. That is why it was decided to make a new foundation for these monuments, so that one could work around and under them.
First in 2011, a new concrete foundation was made for the tower. The foundation plate was suspended in a steel frame and then the Bagijnetoren was lifted half a meter and moved 18 m to the side. This created enough space to build the deep walls for the railway tunnel. The tower was then moved back onto place. Now it stands directly on the roof of the railway tunnel, with its new foundation.
The Bagijnetoren Tower is being displaced by 18 m (copy right ANP).
However, there was not enough space to pull the same trick with Windmill de Roos and its outbuildings. So the mill had to stay where it was. First, a large part of the mill was dismantled, in particular the stage and its sails. Then 45 steel poles were placed inside and along the mill and outbuildings. Next, a concrete foundation slab was also placed under the entire complex. The deep walls could thus be made along that slab without the mill collapsing by vibrations or deformations. Finally, the mill and outbuildings were jacked up one meter to install the roof of the railway tunnel. Here you can see a nice video about the lifting of the mill.
Windmill de Roos is being elevated by 1 m to construct the roof of the railway tunnel (copy right ANP).
When the works were done, the mill could be lowered again and it now stands directly on the roof of the railway tunnel. In 2016, the mill was rebuilt. The masonry was repaired and the mill was painted. Unfortunately, the two cross beams of the sails had to be replaced and that took some time. The mill was therefore not fully operational again until May 2023.
Windmill de Roos on the Willem van Oranje railway tunnel – you are looking towards Rotterdam.
