Bioretention: from copy‐pasted standard solutions to sophisticated design (2016-2023)

Stormwater bioretention implementation is rapidly increasing in Sweden. However, bioretention faces challenges when implemented in Sweden due to the cold/temperate climate which may interfere the bioretention function.

But given the lack of practical experience and non-existing Swedish design guidelines, most current projects are not designed sufficiently. This imposes wasted municipal investments in malfunctioning facilities. The project "Bioretention: from copy‐pasted standard solutions to sophisticated design adapted to Swedish conditions" will develop and test sophisticated designs for Swedish conditions for a more successful implementation of bioretention in Sweden with respect to climate.

Since 2005, the main applicant Godecke Blecken at the Urban Water group/Stormwater&Sewers at LTU has developed climate-adapted designs for bioretention and tested these in laboratory. This broad knowledge base is the foundation for more sophisticated designs for bioretention adapted to Swedish conditions. Focus was on testing the function of bioretention in cold climates, develop a filter material adapted to this climate, evaluating the effect of road salt on bioretention function and investigating adapted plant species. In this project, we will - based on this knowledge and international experience - further develop, evaluate and compare different bioretention designs in field. Common for these is that they include design elements to adapt the systems to the cold climate.

In a three-step approach we will first evaluate standard design bioretention. In a second step we will design sophisticated systems in field which are based on the outcomes of WP1, the existing experience at LTU and international experience. Thirdly, we will - based on the results from WP1 and 2 - implement and test the "best" solution in a demonstration facility.

The results will be summarized in a design guideline for bioretention in Swedish conditions.

The project leader is Godecke Godecke Blecken who will work in this project together with Maria Viklander. Also Katharina Lange will participate in the project.

This project is a collaboration between Urban Water Engineering at LTU with MittSverige Vatten&Avfall (Sundsvall), Stockholm Water, Växjö municipality, Täby municipality, Malmö municipality /VA-Syd and Örebro municipality. In these municipalities the test sites will be built and evaluated. The project is financed by Formas (9,5 MSEK) and the Swedish Water and Waste Water Association (2 MSEK). The other project partners contribute with co-funding.

Godecke-Tobias Blecken, Maria Viklander, Katharina Lange och Heléne Österlund