German water management, ‘sponge city’ future
Germany feels the impact of climate change more commonly than is often realised. Water presents dangers both in its abundance and scarcity. Melting glaciers in the Alps means that large-scale flooding of the Rhine and Mosel rivers is a constant threat. Yet in parts of the former East Germany, there exist regions with less rainfall than on the arid Mediterranean island of Crete, according to the Berlin Senate Department for Urban Development.
A sustained German commitment to innovative water management is the result. Rainwater collected at Frankfurt Airport’s Terminal B has long been used to supply the lavatories. Further, Sony and DaimlerChrysler also use rainwater for lavatory flushing at their headquarters in Berlin, as does the Association of German Chambers of Industry and Commerce. According to Roland Berger and the German Environment Ministry, the country’s sustainable water technologies market is forecast to grow at a rate of 12 per cent annually to 2025, making it the fastest growing segment of the German greentech industry.
The benefits to business from smart management of water are clear: reduced running costs, enhanced organizational reputation, and contributing to sustainability
The benefits to business from smart management of water are clear: reduced running costs, enhanced organizational reputation, and contributing to sustainability. The risk of operational problems is lessened. Cutting the amount of rainwater that goes into sewerage systems lightens peak loads, reducing flooding risk. Rolling back the asphalt and concrete that encases so many cities at ground level also cuts this risk by making it easier for water to escape.
In 2017, the Berlin Senate released a plan to turn the capital into a “Sponge City”. The plan aims to promote green roofs in new buildings as well as retrofitting old ones, and to establish urban wetlands, for example in parking lots, which can absorb and store water during heavy rainfall. Property values are likely to benefit in the long term.
The Roof Water Farm in Berlin goes further and investigates opportunities to irrigate and fertilize roof-top greenhouses. Technologies for water treatment and plant and fish cultivation are being examined at a test site.In Hamburg, the aim is for 70 per cent of all suitable rooftops to be topped with vegetation by 2019. The Hamburg Ministry for Environment and Energy provides building owners with subsidies worth up to 40 per cent of installation costs. The immediate spin-off is lower energy costs because of improved building insulation and reduced maintenance because of the longer lifespan of green roofs. The estimated lifespan for a green roof in Europe is 30 to 50 years, according to the Hamburg Ministry of Environment and Energy.
In Hamburg, the aim is for 70 per cent of all suitable rooftops to be topped with vegetation by 2019
Sponge city concepts won’t work in isolation. Joined-up thinking and joined-up policies are needed. The netWORKS 3 project, funded by the German Federal Ministry of Education and Research, offers guidance for municipalities and water companies in Frankfurt and Hamburg. The project seeks to tap wastewater as a source of power for heating. Old sewer networks are a source of leaks, but netWORKS 3 explores their potential for a new life as collectors of waste water.
Under netWORKS 4, experts are working to improve synergies between three types of infrastructure: grey (rain and wastewater discharge infrastructure), green (parks and green spaces) and blue (water bodies and water surfaces). By doing so, they aim to save resources and mitigate the effects of climate change, with the initial focus on two cities: Berlin and Norderstedt. Innovation in wastewater technology is further promoted at the federal level by Germany’s Environmental Innovation Program, which offers grants of up to 30 per cent of the cost of pilot projects.
Innovation in wastewater technology is further promoted at the federal level by Germany’s Environmental Innovation Program, which offers grants of up to 30 per cent of the cost of pilot projects
Many German cities already have the tools to provide sustainable urban environments that benefit companies and raise quality of life. In Dresden, an elaborate piece of architecture known as the “Court of Water” created by Annette Paul, Christoph Rossner and André Tempel even channels rainwater through a series of trumpets to produce music. A good location for a remake of Singin’ in the Rain, and a great way to inspire the modern city to adapt its water management into the community.