With higher volumes of rainfall and more intense storms expected in the future, municipal stormwater networks are likely to come under increasing pressure. What can be done to mitigate the impact of climate change on urban flooding?

Researchers in Finland have been working on one possible solution: permeable pavements.

VTT Technical Research Centre of Finland Ltd teamed up with industrial partners to develop new pavement materials that can help minimize the problems caused by storm and runoff water in urban areas, as well as prepare for the increased volumes of rainfall expected in the future.

The solutions incorporate materials such as pervious concrete, porous asphalt and concrete and natural stone block paver systems where the material used in the joints or openings allows high filtration of water to the substrate, rather than burdening stormwater collection systems or transporting run-off pollutants to local water bodies.

Researchers also had to consider the freeze-thaw durability of materials, as well as their behavior in cold weather conditions. A key focus of the project was material performance in the subarctic climate, where infrastructures are subject to freezing and thawing ground frost as well as de-icing salt and sanding.

The resulting pavement solutions are specially designed for Nordic conditions. They are suited for areas with low traffic volume, such as parking lots, pavements and courtyards.

Pilot installations will take place this spring in the cities of Helsinki, Espoo, Vantaa and Oulu.