Building Physics of Urban Areas project
Another starting point for counteracting heavy rainfall and droughts lies in the road surface. Instead of sealing roads, cycle paths and sidewalks with asphalt or paving stones, teams of experts involved in the project “Building physics of urban areas” at the Fraunhofer Institute for Building Physics IBP are experimenting with a hydroactive road surface design. “Our newly developed system not only allows the water to seep out, it stores it mainly in underground stormwater detention layer — cavities in the ground that are enclosed by a watertight material,” explains Michael Wuerth, Project Manager for climate simulation. When it rains, these buffers fill up and counteract flooding, rather like any dry spell that might follow. For over the course of the next few weeks, wicking elements integrated into the underground stormwater detention layer transport the stored water back to the surface and emit it into the environment by means of evaporation. This also develops a cooling effect. Unlike commercially available underground stormwater detention boxes, which are interconnected as cubic underground reservoirs with a storage capacity of several thousand liters and therefore require a large ditch, the innovative, flat system can be integrated into the road without any notable additional work. “We are simply replacing one or more of the substructure layers required with our planar blind drain system,” explains Wuerth. The researchers are planning on the systems being able to take up to 200 liters of water per square meter. They are currently in the experimental phase.
Fraunhofer-Gesellschaft
