Professor Kurth, when it comes to the future of cities, people often talk about urban resilience. What does that mean?
In the Urban Resilience Memorandum, we defined a triad of assets for cities. First, resilience means “return”, i.e., return to the original state after a crisis or disaster. However, this is not enough for the sustainable development of the city. That is why we need two more dimensions: adaptation and transformation, that is, preparing cities for crises and transforming them so that they become more sustainable and resilient in the future.
How do cities become stable?
The first step for a city is to be aware of future crises and disasters. A stable and resilient infrastructure that works well even in a crisis is essential. But it is also about considering the aspect of stability of construction projects and assessing future crises. This is part of preventive planning. This includes risk assessment, for example to see where there is a risk of flooding or where heat events are expected and whether people at risk live there. So far, Germany is lucky because there haven’t been many disasters yet – hence there is a lack of risk awareness and there are few things to do.
You’re also talking about “colorful” cities. What do you mean?
There are four terms green, blue, gray and white from the climate adaptation strategy, which are very closely related to the idea of stability and define goals for cities. A green city means more vegetation for microclimate and air quality. Blue city means more water, i.e. evaporation surfaces and open waterways to resist extreme heat. The gray city leads to more shading, especially in the summer. White city refers to the albedo effect of white surfaces that reflect sunlight, and thus prevent excessive heat of the city.
Are there cities that are considered exemplary when it comes to stability?
There are also a few that we have examined. In Europe, for example, Rotterdam, among other things, on the subject of flooding. In Asia, for example in Hong Kong, Taipei or Japanese cities, have been exposed to the effects of pandemics and earthquakes in advance. But cities in India and the USA are also pursuing interesting approaches. Therefore, it is important to internationalize urban development policy in Germany and strengthen exchanges, for example through resilience town partnerships. It is important for us to learn from each other.
professor dr Detlef Kurth from TU Kaiserslautern was, among other things, chairman of the expert group for the preparation of the “Memorandum Urban Resilience” for the Federal Ministry of Housing, Urban Development and Building.