Berlin is becoming a sponge city: This is how the metropolis is fighting against water shortages!

Berlin is becoming a sponge city: This is how the metropolis is fighting against water shortages!

Water shortages in urban areas are increasingly becoming an explosive issue. In Berlin, people are already thinking one step further and are planning to become a “sponge city”. With the concept of not only storing rainwater, but also releasing it again in a targeted manner, the city is trying to meet the challenge of climate change. This goes hand in hand with the goals of the German adaptation strategy to climate change, which aims to promote innovative solutions in urban development.

The need for these measures becomes clear when one considers that Berlin is in a dry region of Germany and water supply becomes increasingly problematic in summer. To counteract this, nine huge underground rainwater collection basins have already been completed. A particularly impressive catch basin with a depth of 30 meters will be fully functional in 2026 and can hold around 17,000 cubic meters of rainwater. During heavy rain events, excess water is discharged into these basins before being pumped to wastewater treatment plants for further treatment.

How does sponge city work?

But what exactly does it mean to be a sponge city? At its core, it is a clever concept that aims to make better use of sealed areas in cities. Loud Furniture researchers Cities can revolutionize how they deal with rainwater by installing permeable soils, more green spaces and water storage. The aim is to store the excess water and release it slowly, thereby protecting many rivers from overflows and sewage.

Particular attention is also paid to preventing mixed water overflows. In Berlin, 2,000 out of 10,000 km of sewers are mixed sewer systems. In the worst case, these lead to fish deaths and a lack of oxygen in water bodies. To address this problem, the city has passed a law that stipulates that only a small portion of rainwater on new building sites may flow into the sewer system. The rest must evaporate or seep away.

Green infrastructure for the microclimate

The federal government sees the sponge city as part of its comprehensive adaptation strategy to climate change. Innovative approaches to green infrastructure, such as those in the THE are required to strengthen the microclimate in cities. The DAS monitoring report also shows that research shows that less than half of residential properties are insured against natural hazards. There is a need for action here.

In terms of climate protection, the quality of life of city residents also benefits. Greening measures such as creating ponds to store rainwater can not only keep water clean, but also help cool the city and protect it from flooding. An example could be a new apartment block equipped with a pond and plants to purify water.

More and more cities are relying on the sponge city concept. Pilot projects are already taking place in Switzerland, where over 43 million francs are being invested in structural prevention measures. In Winterthur, for example, rainwater from school buildings is used to irrigate parks and green spaces.

With the right measures and the will to change, the idea of ​​the sponge city could set a precedent not only in Berlin, but in many other cities of European origin. The time for climate-friendly concepts in cities is now – something is important!