Expert insights: Erle Kristvik

How do you take into account the need of increasing resilience in your projects?

“On a very technical level it would be analysing how stormwater should be managed. The things we build should remain for at least 100 years, so we need to account for climate changes. What kind of functions do we need to secure, and how can we reduce peak runoff and stormwater volumes?”’

The things we build should remain for at least 100 years

The solutions to these questions are always nature-based, blue-green infrastructure, Kristvik says.

“It could be a green spot or area that collects stormwater and detains it. We also always think about multifunctional use. On the one hand, we need to protect our buildings and societies from large quantities of stormwater, but we will not experience that very often. So the most sustainable way is to use the green areas for other things in between, like a depressed park or a football field.”

Storm water management

Where do you see the biggest challenges when it comes to resilience?

“The first challenge is related to how we perceive risk. Denmark had this extreme rainfall a few years back that led to significant action and the creation of resilient cities that can withstand almost anything. Today Denmark has a high-risk perception and actual action while Norway has not experienced this crisis yet. We are all waiting for it to happen, so we are not seeing any action.”

The other challenge involves having the right balance between resilience and sustainability.

“There are many examples of high-risk perception leading to very technically robust measures, such as large-scale, grey infrastructure for stormwater detention and conveyance that are not necessarily the most sustainable ones. You need to have climate mitigation, adaptation and sustainability – all of them need to be front of mind at all times.”

Stormwater and multifunctional are the two words that keep coming up when talking to Erle Kristvik.

She highlights two R&D projects that Sweco is participating in. One is ’Sustainability analysis of climate adaptation measures’ in cooperation with Norwegian Sintef, one of Europe’s largest independent research organisations, and the other one is ‘Space for Resilience’ or SPARE.

“In our Sintef project, we focus on blue-green infrastructure where we have the technical solutions. But if we have to choose between measures that are all resilient, how do we know which one is the more sustainable? So, we are codeveloping decision tools for that purpose.”

In SPARE, Sweco has been engaged to perform research that will answer the question of how to plan for stormwater, biodiversity and recreation to increase urban resilience.

“The municipalities can request these kinds of solutions in projects, but almost all areas are already developed, and you don’t have that space. At the same time, we don’t have time to sit and wait for all the lots in the city to be redeveloped in order to implement measures, so how do we solve that?”

The solution studied in this project is called cross-sectoral, polycentric collaborative SPARE management.

“There are so many actors and stakeholders involved in the development and use of blue-green solutions, but one actor alone cannot make this implementation happen. So how can collaborative cross-sectoral models boost actual action?”

Kristvik also calls for highlighting the positive impacts of measures in collaborations.

“Stormwater does not stop in one area, so you have to keep track of what’s happening in surrounding areas. We are all quite good at analysing the negative consequences of doing things, but I don’t think we put enough thought into the positive impacts of the blue-green measures.”

Preparing for a rainy day, by Sweco