As part of his state visit to the Netherlands, the Japanese Emperor Naruhito, accompanied by King Willem-Alexander, visited the Deltares research institute on Wednesday, a leading organisation in the field of water and subsurface research.

The ties between Japan and the Netherlands go back hundreds of years. One of the main factors linking the two countries is that both live alongside water and are constantly seeking ways to adapt to it. ‘Both countries excel in the field of water management,’ said Vincent Karremans, Minister for Infrastructure and Water Management, at the opening of a brief meeting during which Deltares presented itself to the dignitaries. ‘It’s a draw in this respect too,’ he remarked, referring to the recent 2–2 draw between the two countries at the World Cup.

According to the minister, cooperation in the field of water management has taken on a different character over time. Whereas knowledge used to be transferred, the emphasis is now on learning together. ‘Climate change and rising sea levels pose a challenge for the whole world,’ said Karremans. ‘In these areas, we are building up knowledge from which other countries can also benefit.’

Keizer Naruhito krijgt een rondleiding door de Hydrohal van Deltares, in gezelschap van Annemieke Nijhof en Dirk-Jan Walstra, die samen de directie van Deltares vormen, en (op de achtergrond) koning Willem-Alexander.

Natural systems

Annemieke Nijhof, Managing Director of Deltares, said it was crucial for the Netherlands to have the strongest possible knowledge base in the field of water. ‘The combination of human intelligence, an in-depth understanding of water and the subsurface, experimental facilities and digital innovation in data and models forms Deltares’ unique strength.’

Whereas water management has long revolved around control and rapid drainage, there is a growing realisation that we need to work more in harmony with natural systems. In a brief presentation, Bregje van Wesenbeeck, Scientific Director at Deltares and also Professor of Natural Solutions at Delft University of Technology, elaborated on this. As well as flooding, drought and land subsidence are equally significant problems, as are climate change and the loss of biodiversity. This calls for a different approach, one that allows space for water and natural processes.

Van Wesenbeeck also drew a parallel with Japan. There has long been a tradition there (kasumi-tei) in which technology, landscape and society come together, for example in open dyke systems and coastal forests that offer protection against wind and waves. ‘Good solutions have one foot in the past and one in the future.’

Flood risks

Emperor Naruhito, who had once conducted research into water management on the River Thames whilst studying at Oxford, was then given a tour of the Delta site. The first stop was a large research basin where he was briefed, amongst other things, on Delft-FEWS. This open-source platform is used worldwide for water management and forecasting. The system combines real-time measurements, such as rainfall and water levels, with models and weather forecasts.

The joint research project in Hokkaido, in which Delft-FEWS is set to play a role, was also presented to the Emperor. This region of Japan is severely affected by climate change and suffered major flooding in 2016. Dutch and Japanese organisations, including TU Delft and Rijkswaterstaat, are collaborating here to better understand and predict flood risks.

Het gezelschap in de Deltagoot, waar onderzoek plaatsvindt naar de gevolgen van golfslag op onder meer dijken.

Clay blocks

Naruhito was also shown a scale model study of the Oosterschelde barrier. Commissioned by Rijkswaterstaat, Deltares is using this to investigate the effects of sea-level rise and heavy wave loads on the barrier, in order to better inform maintenance and future decisions.

Finally, the party witnessed a test on the erodibility of clay dykes in the Deltares Deltagoot. In this study, the Brabantse Delta Water Board, Deltares, Fugro and Arcadis are collaborating to gain a better understanding of how grass-covered clay dykes respond to extreme wave loads. For this purpose, clay blocks from an existing dyke were used, which were assembled into a dyke in the Deltagoot and then exposed to high waves.

After the visit, the heads of state hurried back to the capital, where the state banquet was scheduled to take place at the Paleis op de Dam in Amsterdam.

 

Pictures: Guus Schoonewille