On Rundelsgatan the sidewalk and the traffic lanes are paved with asphalt. This kind of surface traditionally generates rainwater runoff that flows directly into the sewer system without local treatment. The design brief for this project was to increase street safety and at the same time create new stormwater functions to manage rainwater on site.

The completed design includes rain gardens in the form of submerged plant beds that can retain and clean rainwater on site. Placement of the rain gardens slows down traffic and increases the safety of the street. The rain gardens are built on top of OSL (open subbase layer), which provides both a sufficient root zone for vegetation and the capacity to retain rainwater for plant irrigation. Rain gardens increase the areas resilience to extreme weather such as drought and cloudbursts and make the street more attractive.