The United Nations is proclaiming the motto “Accelerating Change” for World Water Day on 22 March. The message: because the pressure on drinking water reserves is increasing worldwide, the change towards sustainable water use must be accelerated. The last summers of persistent heat and drought have shown that the water transformation must also gain momentum in Germany. Scientists at ISOE – Institute for Social-Ecological Research are investigating how sustainable water supply can be achieved in municipalities, for instance through the consistent use of service water in the building sector, including existing buildings and not just newly built ones.
The sustainable use of water is one of the central goals that the UN wants to achieve by 2030. And due to the increasing pressure on water resources time is pressing. Bottlenecks in the availability of good quality water in sufficient quantities are becoming ever more frequent, not only in drier regions of the world. Even in water-rich countries like Germany, drinking water sometimes becomes scarce regionally, especially in phases of prolonged heat and drought. “The economically use of drinking water is becoming increasingly important in view of climate change and is already practized in many areas,” says ISOE researcher Martina Winker. “We cannot, however, speak of sustainable water use as long as high-quality drinking water, which is treated at great expense of resources, is still used in large amounts on a daily basis for flushing toilets.”
Crucial for the water transformation, she says, is that the drinking water tap is not turned on for all kinds of purposes, be it in the industry, in commercial, public or residential buildings. “We have to get to the point where so-called service water can be used depending on the quality required,” says Winker. Service water is obtained from rainwater or from only slightly polluted household water and is suitable for example for flushing toilets. “Municipalities can accelerate the water transformation if they promote the consistent use of service water in public and domestic buildings as well as in trade and industry.” To achieve consistency, we need apartments with piping systems that allow service water to be treated and used separately from drinking water. It is technically feasible and already being done in new construction areas and should become standard, also in existing buildings. “The transformation of water infrastructures in existing buildings is certainly a challenge for municipalities, but implementable in the long term,” says Winker.
You can find the entire press release here.