The idea
The Netherlands Water Museum is the brainchild of Henk van Brink, Dyke Warden of the Rhine and IJssel Water Authority. In 1998 he had an idea for an information centre on the Rhine and IJssel Water Board District. With some external assistance this quickly developed into the Netherlands Water Museum.

The location was perfect: the old 13th century Beguine Mill on the Sint Jansbeek in Arnhem’s Sonsbeek Park. However, the mill and the adjacent ‘Aquarium’ building were too small to house a museum. Furthermore, as the Mill, the ‘Aquarium’ and Sonsbeek Park are all national monuments, it was impossible to place another building nearby. The answer was to build the museum underground. Van Hillo Verschaeren Architects from Hertogenbosch devised the plans and supervised the construction.

The building process
The building process consisted of two parts. First the old Beguine Mill and the ‘Aquarium’ were renovated. Then work started on the second part: the building of an underground facility measuring 2,000 m2 in the front garden of the mill. This took the form of an underwater construction. Sheet pile walling was installed then the construction pit was dug. As the groundwater level was so high the pit was soon flooded. A thick layer of underwater concrete had to be laid before this water could be pumped out. Huge pillars were installed to support the roof once the pit was free of water. The pit was then sealed off and a metre of soil was laid on top of what was to become the underground museum.

Opening
The interior was installed and the museum unofficially opened on the 13th of December 2003. After a trial period of a few months the Netherlands Water Museum was officially opened on the 7th of June 2004.