Vorarlberg workshops show how breaking up asphalt can cool neighbourhoods

Workshops in Vorarlberg are showing residents how removing asphalt and planting greenery can help cool built-up areas and let rainwater soak into the ground, ORF reports.

Asphalt can heat up to 60 degrees Celsius in summer, while a planted surface can stay around 20 degrees, said Kerstin Riedmann, managing director of the Bodenfreiheit association. Green spaces also allow rainwater to seep into the soil instead of flowing straight into drains. Evaporating water helps cool the surroundings, and the ground can absorb more water during heavy rain.

For small areas, no heavy machinery is needed, said earthworks specialist Mathias Hoch. The asphalt is cut into a triangular shape and then broken up piece by piece with a pickaxe and sledgehammer. Hoch described the work as “a bit like a workout”. Most of the tools are likely to be available at home, while a cutting machine can be hired.

After the asphalt is removed, the ground must be filled according to how the space will be used. At a workshop in Frastanz, participants added gravel and sowed a gravel lawn. Mixing seeds with soil beforehand can make them easier to spread.

Plant roots help water seep into the ground, said landscape planner Simone König. A gravel-only surface can become compacted over time, while rain is more likely to soak in where plants are growing rather than run off across the surface.

Participants at the workshops have used the tools themselves to learn how to remove paving on private property, such as a strip of driveway or an unused parking space. The association recommends hiring a specialist for larger areas.

Bodenfreiheit has held workshops in 10 municipalities this year, Riedmann said, and plans to hold more in spring 2027. Its BODAguat project is supported by the state of Vorarlberg and the European Union, so participation is free for municipalities and interested residents.