Jointly strengthening  a dyke and mutual trust

Case

Jointly strengthening a dyke and mutual trust

Shortly after the start of the research project SoSEAL, researchers could carry out the first field tests. And that bore fruit. Both the participating companies and the researchers are positive about the mutual collaboration. What are the underlying reasons for this consortium's success? ‘Here, every single person truly left their comfort zone.’

‘It looks like our PhD student will complete the project in four years, and that is partly due to this consortium. The collaboration has helped him considerably.’ With those words, Timo Heimovaara, Professor of Geo-Environmental Engineering and project leader opens the user committee of the research programme SoSEAL. A meeting with all of the parties involved in this project that takes place in the middle of the De Biesbosch nature reserve at a location of water company Evides. Three reservoirs of the drinking water company are located in this area. The De Gijster reservoir is a test location for the experiments within the research project that seeks to find a natural way of decreasing the porosity of the reservoir bed. This must prevent the seepage of groundwater and make the surrounding dykes more stable.

Leaking dyke

For water company Evides, it was clear from the start of the project that the application of the research could be interesting for them. Each year, about ten percent of the water from the reservoirs is lost because it seeps through the dyke, states Daan Spitzers, regional head Petrusplaat. And if material flows with this seepage water, then the dyke becomes more unstable. The solution is often sought in drainage, but this is a maintenance sensitive and expensive solution. Spitzers: ‘I heard via a contractor that TU Delft was going to do research into making dyke bodies less permeable via a natural approach. I was immediately interested in participating.’

The researchers in the project injected two substances into the deeper layers of the dyke that surrounds the reservoirs: water containing a dissolved substance that consists of broken-down plant remains and aluminium. The idea is that flakes develop from this solution, which coagulate and thus fill up the spaces between the sand particles in the dyke. Then the water can no longer flow away. Eventually, the researchers managed to create a permanent barrier and, therefore, to reduce the permeability by a factor of thirteen. The method could be cheaper than existing techniques and is also environmentally friendly.

Researchers doing field testsPhoto: TU Delft

Field test at an early stage

‘The fact that the collaboration went so well is partly because we could start the field tests just six months into the project’, says Susanne Laumann, who is involved in the research as a postdoc at TU Delft and as a consultant at Tauw. The project is jointly funded by NWO Domain Applied and Engineering Sciences (AES) and the participating companies. In addition to Evides, researchers from TU Delft and the University of Amsterdam are also working with, among others, a research agency, building and contracting companies, engineering consultancies, water boards and Rotterdam City Council. AES's approach is to bring academics and researchers together in a research project that leads to an application and impact for people and society. During user committees the companies and civil society organisations provide input for the researchers and discuss the possibilities for applying the research.

Field tests early in the research project are an advantage because then a wide range of problems are exposed at an early stage. To start with, the soil is always the most important aspect in this type of research: ‘When the results from lab research are applied in the field the soil is always a problem’, says Dick van den Heuvel, who participates on behalf of Heijmans Infra. ‘The heterogeneity of the soil can never be simulated in the lab. This is a problem that we always encounter. And so we need to do field tests.’

Click on the image to watch the videoClick on the image to watch a video about the project

Mutual trust

Nevertheless, laboratory research is typically done for far longer before researchers take the results outside, say both Laumann and Van den Heuvel. ‘Researchers first of all want to culture a sort of trust in the lab before they think about the application. The problem with that approach is that although you build up trust on the research side, it takes longer to build up trust on the practice side. Then there is a risk that you drift apart from each other’, says Van den Heuvel.

In this project, he constantly saw a lot of room for questioning how the research could be applied. ‘On the theoretical side, you work with certain assumptions that can turn out to be different. But that equally applies to the application side. For example, in the first field experiment, we separately injected two types of substances. That proved to be difficult. So lab tests were subsequently performed to investigate whether we could bring the substances together into a single flake. We tested that substance at Evides. And there we encountered new problems. This, in turn, led to new tests.’

If research is too fundamental, then the market no longer immediately recognises it as a solution to a problem

That means we learned quickly, says Frank Volkering from engineering consultancy Tauw. ‘Looking back, you can say that the first experiment so early in the research had little chance of success. But without that test, there would never have been the firm conviction that we had to find something to allow the two substances to be injected together. Everybody knew that we had to look for an alternative.’

If people had mainly focused on the fundamental track from the start of the project, then the importance of this work for the users would have been less clear, says Volkering. The constant request for feedback from users helps you to stay focused on the problem, says Van den Heuvel. ‘If the research is too fundamental, then the market no longer immediately recognises it as a solution to a problem.' Laumann: ‘In this case, every single person truly left their comfort zone.'

Researchers and partners during the user committee at EvidesResearchers and partners during the user committee at Evides

Ongoing contact

The reactions from both researchers and users are positive. But what if the interests differ, which is not inconceivable in a project with different parties. According to Laumann, this was mainly an issue for expectations about the speed at which the research progressed: ‘We noticed that soon after the completion of the pilot, the companies were keen to have results. However, we were only working with three people on the project there. Furthermore, as a scientist, you are critical; you are cautious about publishing, and sometimes you want to recheck things.’ Van den Heuvel endorses this point. ‘Analysing the results can easily take a year. Then there is a chance that the user's attention will be drawn towards something else. Ongoing mutual validation is therefore needed.’

The solution lay in communication, and a clear management of expectations, says Laumann. The researchers continued to communicate with the users during this period as well. ‘We received the provisional results on a sheet of A4 that we could show to interested parties’, says Van den Heuvel. ‘That certainly helped. Remaining in contact with each other is an important condition.’ Spitzers refers to the contact with the researchers as ‘low threshold and easy’. At the start, Laumann made very clear agreements about what each party would do, she recounts. ‘My role was to ensure that this project ran smoothly. I had to find a single language that everybody spoke.’

Photo: TU Delft

Bridging role

Asked about further conditions for success, Van den Heuvel lists the role of Laumann. ‘She was involved with both the researchers and the users.’ In this way, Laumann formed a bridge between both sides. An important but also tricky role, thinks her colleague Frank Volkering. ‘You can get involved in conflicts.’ This position was not deliberately chosen. Laumann had just gained her doctorate and had recently started to work at Tauw when SoSEAL was awarded funding, says Volkering. We then examined whether she could fill this postdoc position on a part-time basis. That has worked out well. She talks to me at her work and in Delft she talks with the researchers. As a result of that everybody talks to each other.' ‘Both sides are represented’, adds Van den Heuvel.

And the fact that the project went well also played a role. The commitment of the parties was considerable from the start, says Volkering. ‘However, as the success of the project increased, the commitment of the participants grew further. And that also applied to me. I started to believe more in what we were doing. Then you automatically start to work harder and harder on it.’

The first results were therefore enthusiastically received by the industry, says Heimovaara. Both the researchers and the users want to continue the research. ‘Now we need to approach parties in the market to establish follow-up pilots’, says the project leader. Together with the members of the user committee, Laumann is looking for end users where further tests can be performed. For example, they have given presentations at water boards. Spitzers from water company Evides hopes that there will be a follow-up study: ‘We have learned an awful lot from the pilot. I hope that we can apply the technology even more in the future. The dykes around the reservoir s are 50 years old. They need to last at least another 50 years. It would be great if this method could contribute to that.'

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