Pluvial urban flooding in a densified Sweden : do sustainable flood management and densification fit together?

Sammanfattning: Pluvial urban flooding occurs in many parts of the world, including Sweden, often with severe consequences. Climate change and increased urbanization exacerbate the risk of urban flooding, and traditional urban drainage systems are unable to keep up. Alternate solutions utilizing green infrastructure have thus emerged to manage flooding in more sustainable ways. At the same time, a popular planning strategy for urban growth is densification, which can potentially put these sustainable systems at risk. Despite this apparent contradiction between sustainability in urban flood management strategies and densification, the aim is evidently to include both in the same urban landscape. This contradiction is explored in this thesis, through an investigation into Sweden’s national and municipal strategies for urban flood management. An analysis of these strategies is then made with the concept of the technological fix, to discuss whether or not technical solutions are used to bypass other necessary solutions for urban flood management. It was found that Sweden has a number of national laws and guidelines pertaining to flooding, as well as a national strategy for climate adaptation. Investigating the municipalities of Malmö and Uppsala yielded rain gardens, limiting hard surfaces, and multifunctional areas designed to handle flooding and retain water as strategies used on a municipal level in Sweden. Furthermore, it was shown that both municipalities also aim for further urban growth through densification, since housing needs to be provided for their growing populations. While sustainable solutions have the potential to effectively manage flooding, they could still be considered technological fixes in that they are seemingly used to ensure the possibility of continued urbanization, without requiring society to really change. On the other hand, the increased implementation of nature-based solutions could be considered as steps towards a societal change regarding how cities are planned and how resilient or adaptable they are. Though densification has its downsides, other forms of urban planning strategies do as well, and until a better alternative has potentially been devised, the desire for densification is unlikely to abate. Thus, even if sustainable solutions for flood management are used as technological fixes, it is still vital to include them in densification projects since they are necessary to meet current and future demands for protection against pluvial urban flooding.