Digital Twin Cities – the Magic Mirror of Stormwater Management

by Oscar Warmerdam on Monday, August 12, 2019

Climate Resilience Summit in Boston Part 2: Digital Twin Cities

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Many coastal cities are already experiencing the real effects of climate change. Boston is one of these cities and the problems are expected to increase significantly over the years to come UNLESS approaches are found to both mitigate the changing climate itself, but also its already existing effects.

The best solutions are found if you can model the future. Did you know of the amazing digital tools out there that can predict city-wide flooding scenarios? Continue reading to find out more!

You can read more about the situation in Boston in Part1 & III of this article series:
Boston – a Drowning City?
Green Roofs for Successful Stormwater Management in Boston

The hopeful story of Boston

Boston managed something that is just short of a miracle and that is the clean up of the slushy, toxic and polluted Boston Harbor. In just over a decade the harbor went from being a wasteland to being one of the cleanest big city harbors in the US. This was no small feat, but they did it. They found collaborations, made people enthusiastic and hopeful. They showed that change was possible.

We believe they will apply the same approach to the intensified stormwater and rising tide problems, which truly are two different problems to be solved independently. This time, however, things are different. At their disposal, they now have tools to educate, model and run doomsday scenarios that calculate estimated physical damages AND the economic damages.

Digital stormwater management tools

One such tool is the Digital Twin technology. It’s a virtual but identical replica of the city that allows you to run AI-supported scenarios with ultra-complexity that can deal with a multitude of intertwined scenarios all at the same time and play with it. In short, you get a virtual representation, a digital copy of the city.

The Digital Twin City model will show what districts will lose power first during a storm, what roads are accessible to emergency response teams, what underground train stations will flood, which electric switches will crash and so on. In each storm scenario, it can demonstrate what solutions are most effective and how they should be deployed. This allows policymakers to prioritize and make it a gradual process of upgrades and improvements that is digestible and manageable.

An example of a twin city modeler, focussing on urban resilience (strategies) is STAIN by the Dutch company Royal HaskoningDHV.

The socioeconomic value of digital stormwater modelers

The digital twin city also allows them to show developers why they need solutions, and what needs to be done where first.

Let’s take one example to show you the socio-economic complexity of stormwater management and how these virtual model scenarios can make our society more equal and prepared. We can all agree that water needs to go somewhere. For example. if you block the water from entering fancy Section A of the city, the water needs to flow elsewhere. Perhaps, you might force the water to go into Section B. My qualified guess is that people from Section B probably aren’t that excited about this solution.

Thus, inhabitants and politicians together decide that the water can’t flow to Section A or B, so they prepare and try to send the water elsewhere. The water ends up in Section C, the least affluent Section, and this group does not have the tax base to defend itself. You can imagine the political upheaval that these playbook scenarios will ignite. But at least we will know in advance and we can do our best to prepare to avoid situations like these.

During the Summit, we were also positively surprised how much awareness and care there was given to lower-income regions of the city. It is depressing that one gets surprised by such positive news, but the reality is that these perspectives aren’t often considered.

In almost all cases these people lived in the most vulnerable areas, and only when gentrification took place was this no longer true. The city-wide effort to make sure these people are not simply left behind or shoved aside was humbling. It was also unexpected that this is once again very much a race-related matter, which was a topic we did not expect to enter into this picture, but policymakers are trying to make sure that while they make the improvements, they should do so and place extra emphasis on improving the quality of life for this lower-income/minority group.

In a nutshell, better analytical tools allow city planners to run scenarios to prepare better, and at the same time use that capability to communicate more clearly with its citizens. The economic damage of disasters is identified and calculated and at the same time, the economic benefits of green infrastructure are mapped as well.

Very well done, Boston!!!

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