Blog Water Security

by Thijs Visser

March 11, 2020

Water plays an important role in spatial development. That’s why I’m often asked how one should deal with the water component in a spatial development plan. The reason for the question is clear. A development cannot have any negative consequences for the environment. And that’s why the water management in the plan must be in good order. To make sure this is the case, the public authorities have set down requirements for a plan’s water component. And it is on the basis of these requirements that I design a plan’s water management.

If the numbers are good

I see that the requirements are often defined in technical terms. This makes a plan implementable and testable. Every policy includes the plan’s minimum drainage, the volume of water to be stored and the maximum discharge. And these form the bases for the plan’s assessment. I often notice that a plan is almost automatically approved if these specific numbers are good. A blue mark on the layout drawing suffices for water storage. Hard numbers: hard water.

An extra dimension

Testing for bare, technical requirements is simple, but it has its limitations. For instance, the technical requirement concerning the water storage volume suggests that this must be effective. This means that the volume is sufficient to contribute to good water management within the plan, and to prevent any effects on the environment. But the objectives are four-dimensional, because they have to do with effects in space and time. There is no suitable approach to this, so there’s a risk that a solution will fail in achieving its objective.

And this at a time when effectiveness is a high priority. I see this emphasis on the importance of effective operation primarily in the way in which climate adaptation is positioned in policy. Besides the above-mentioned technical requirements, I now also have to demonstrate for instance that no flooding will occur in the case of extreme precipitation. This case perfectly illustrates the four dimensions: a combination of hard-to-estimate water volumes at unpredictable moments. It may be clear that a storage calculation alone is no longer enough, and that it needs to be supplemented with a thorough spatial analysis. To meet this need, Dareius has developed the Urban Water Design OpTioneering tool (UWDOT).

Simplicity in complexity

In UWDOT we model the planning area and its environment in the future situation. The planning area is built up virtually on the basis of publicly available data. The spatial development is uploaded, including a new water-level plan, on the basis of the design. This gives us an understanding of the actual effects of the plan on the environment and within the plan’s boundaries. Using a ground-level model, we can see where and how the precipitation surface runoff occurs. This makes it possible to test the effectiveness of water provisions under heavy precipitation.

UWDOT’s power lies in its capacity to clearly show the effects in less than a minute. This makes the tool perfectly suited for interactive design sessions. The model’s visualizations allow stakeholders to quickly absorb the results, which makes complex questions clear and interactively accessible.

I have so far applied UWDOT in more than ten projects. What strikes me is that the tool’s use contributes to the mutual understanding between, for instance, the public authorities and stakeholders, and that the effectiveness of the water provisions is placed center stage. Local problem areas and possible solution paths are quickly made apparent, allowing for the creation of spatial quality. Soft water, I would say.

The challenge we now face is to provide a legitimate place for the deeper substantive insights produced by UWDOT within a process that is structured on the basis of the bare, technical policy.

by Thijs VisserSeptember 10, 2019

Thijs Visser is a water system specialist. He is an advisor, among others, on the climate issue: What do the years ahead have in store for us, and how can we prepare ourselves for it? Every month he invites us to accompany him in his advisory work and, as a blogger, shares his experiences with visitors to the Dareius website.

Climate change has become a news item. It’s all over the newspapers and, when asked, everybody has something to say about it. The question often concerns how we should or can adapt to climate change. The stress test is a new tool in meeting the challenge.

The last few years have seen a growing demand for an integrated approach to climate adaptation in the Netherlands. The Delta Plan on Spatial Adaptation (DPRA) is one of the spearhead programmes in this context. The different levels of government work together within the programme on raising societal awareness, and on organising and adapting the working and living environment. The approach focuses on inventorying, mitigating and sometimes also accepting the consequences of climate change. In this way the Netherlands is being made climate-proof, societally as well as spatially. Within this framework, working with various government authorities and regional partnerships, I have been allowed to conduct numerous climate stress tests.

What is a climate stress test, actually?

A climate stress test sheds light on the consequences of climate change for a specific area. Climate change of course affects a variety of sectors and professional activities, which means that the conduct of a climate stress test involves teamwork. Our aim, besides achieving a deeper understanding, is essentially to create support within an organisation so that the outcomes of the climate stress test will strike home and become anchored in the organisation’s daily practices. A deeper understanding of the consequences of climate change demands knowledge sharing. This is why, in the conduct of the climate stress test, we facilitate a well-informed dialogue between area specialists who have different substantive backgrounds.

To provide an insight into the dimension of the climate issue, I make use of the circle diagrams of the National Climate Adaptation Strategy (NAS). The circle diagrams sketch the dimension of the climate issue by distinguishing between ‘climate trends’, ‘climate impacts’ and ‘consequences for sectors’ (‘climate consequences’). In the future, the Netherlands will be hotter, wetter, drier and sea levels will be higher. As a consequence, extreme weather conditions are becoming more frequent and we are observing changes in surface water quality and area discharges. These climate impacts have consequences for different sectors and user functions, such as changes in the hydrology of nature areas, a reduced availability of freshwater, but also a greater exposure to water-borne infectious diseases. Based on the circle diagrams we see climate change as four climate trends, with about 20 potential climate impacts and more than 100 (!) potential climate consequences.

The abundance of potential climate consequences can be paralysing. The frameworks within which the stress tests are conducted must therefore be clearly formulated. The filtering of those climate consequences that one can have an influence upon, helps give a purpose and direction in the elaboration of the climate stress test. By focussing on climate consequences that are concrete and susceptible to influence, the associated risks are rendered manageable. This is crucial for the conduct of a climate stress test. It contributes to raising awareness of the consequence of climate change, and offers an action perspective with regard to what an organisation can do to mitigate undesirable climate consequences. The well-founded filtering of information is therefore a necessary step in determining the essence of the climate challenge for an organisation.

Stress tests for the future

Climate change has widespread societal consequences. Everyone is concerned. The conduct of a climate stress test for an organisation that has a specific responsibility and task, such as a municipality or a Water Authority, involves a specific implementation context. As a result, a climate stress test creates an understanding of a sub-problem. It can therefore be seen as a piece in the national ‘climate puzzle’.

The conduct of a climate stress test thus serves two objectives. By making an inventory of the entire issue at the start of the process and then, after the test’s implementation, by returning to the inventory, the participants become aware of the fact that climate adaptation represents a societal, and frequently national, challenge. But the climate stress test also places an emphasis on the action perspective in terms of the participant’s own responsibilities and tasks. This provides a good foundation for the conduct of the risk dialogue and for setting up the implementation programme.

It is important to continually test the system against new scientific and policy insights. In this way, the stress test can be applied in order to look into the future and, if necessary, to adjust the action perspective. I hope above all else that we can successfully complete the national climate puzzle. In any event, we are today adding a small piece to the puzzle with every stress test we carry out.

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For more information about Water Security, please contact us at:

Thijs Visser tvisser@dareius.com +31 6 51 08 59 47
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