2023-05-30

Let the water take its place!

The City of Gothenburg is a pioneer in water issues to reduce the risk of flooding, and one of FOJAB's partners in the Vinnova project WiCiD. Lisa Ekström from the City Planning Department explains how to work with water as a resource instead of seeing it as a problem.

Why is the city of Gothenburg so far ahead in terms of water issues?

- The background is that Gothenburg is in a risk-prone location with rainwater running down into the city center from surrounding hills, periodic high flows in the Göta River and the ongoing sea level rise. With the expected climate change, we have realized that we need to manage the water issue more like we manage traffic infrastructure, for example. The road network consists of major routes, medium-sized roads and smaller streets, and changes in one place affect traffic in several other places. It's the same with water, it's a complex system that's interrelated and doesn't care about municipal boundaries and is also of great importance for plant and animal life.

How have you proceeded?

- We began by analyzing how the city would be affected by a so-called 100-year rainfall event and developed structural plans for cloudbursts. The Circulation and Water Administration was given responsibility for coordinating cloudburst issues in the city. Water has been given a place both in our internal processes and in concrete terms in the city. The new master plan deals with water issues in a more structured way. When new buildings are planned and built, requirements are now set for water management, much like we set requirements for green spaces.

What is the main challenge in implementing such an approach?

- The municipality does not have control over all land, so it is important to create acceptance among the affected property owners where the water is located. It is important to emphasize added value - which can be difficult when the water or measures do not necessarily create added value for all property owners. The issue is quite new to many, we need to better understand what water can do in the dense city in particular. This applies not only to external property owners but also to officials and politicians. We need to be able to show what different decisions and measures lead to.

- The tool that DHI is developing within the WiCiD research project will be of great help here. It is a visual scenario tool that allows you to test different alternatives in a seated meeting and immediately see the consequences. Where does the rainwater go if you build in different places in the city? What is the difference in runoff if you harden the surface or build a lawn or open stormwater system?

- We see a great need to better communicate and more clearly visualize the consequences of different choices. Here we believe that visual digital tools can be an important piece of the puzzle, which is also why we are involved in WiCiD.

What can municipalities gain from working in a more structured way on water issues?

- The primary concern is that society should be affected as little as possible. Buildings and infrastructure should not be damaged by torrential rain. Ambulance and rescue services should be able to do their job, and people's health and safety should be protected. It is also an economic issue. Here it should be borne in mind that the accumulated damage effect and thus the costs will be greater when torrential rainfall occurs more frequently. Nor should we forget the indirect costs such as loss of production and the impact on people's well-being.

- But it is also about what WiCiD is pushing for, to see water not only as a problem but as a resource in the urban environment. In the dense city, there is great pressure on space. Here, water can serve as an argument for preserving the green gaps in the city and creating beautiful yet functional places for both people and animals. A submerged grass area in a park can become a water mirror. Trees soak up rainwater and reduce the risk of flooding - as well as providing shade during heatwaves, home to pollinating insects, and creating a sense of well-being.

- Things that cannot be clearly measured can be difficult to manage and value in a planning process. What is the full value of planting a tree, for example? Within WiCiD, a methodology is now being developed that makes the soft values of water visible, which makes it easier to get an overall picture and thus to prioritize when we develop the city.