Green roofs in Malmo

by Louise Lundberg & Trevor Graham

Flooding and extreme storm events are expected to follow climate change. In Augustenborg, a unique system of open storm water management and green roofs has been built to deal with this. Instead of leading the stormwater to the municipal treatment plants, it is managed locally. First, extensive green roofs take care of 50% of the rain that falls on them annually. Second, any remaining stormwater is lead into an open system. Water is allowed to evaporate from the ponds, canals and plant meadows. Augustenborg takes care of 70-80% of its stormwater this way. The green roofs have also several properties that save energy. Both the building and the city as a whole stay cooler in the summer - something which becomes even more important with the changing climate. A similar system has been built up also in the Western Harbour and a number of other smaller and less urban stormwater systems are in operation elsewhere in the city. A former hospital site is currently under re-development where all stormwater will be managed on-site to avoid overloading the nearby river. The work is currently in the planning stages in another part of the city to address run-off from an industrial estate.

Malmo is beginning to consider other impacts of climate change with the support of a national research team. Issues such as the impact of heat waves on the elderly population, or gender inequalities in the impact of climate change provide additional challenges that the city will need to consider in more detail. The use of urban greenery in the form of green facades, green roofs, street trees and other urban trees is expected to provide one important way of coping with extreme heat events.

The Scandinavian Green Roof Institute has been established to develop new ideas in the field of green roofs and green facades and facilitate the development of a green roof market in Scandinavia. SGRI also manages the Augustenborg Botanical Roof Garden, and organises study tours of the housing area, now called the EcoCity Augustenborg.