The Hanseatic City Challenge was part of the 37th edition of the ‘International Hanseatic Days’, held from June 15-18 in Kampen, The Netherlands. The central question of the challenge was: How can we protect our Hanseatic cities against the consequences of climate change?
The innovative idea, called the ‘Hanseatic WaterWall’, is a multifunctional measure that increases the use of façades in compact city centers as space to absorb and reduce the flow of rainwater from roofs to the ground and drainage system. Other similar measures, such as green roofs and green spaces, are often metaphorically described as sponges.
In addition to absorbing and reducing the flow of rainwater, the idea includes other functions such as short-term water storage and interactive art. Possible uses for the stored water could be watering vegetation or filling street cleaning machines, while the interactive art could be a creative means of stimulating engagement and raising awareness of climate change and adaptation.