In many parts of the world, water resources are heavily overexploited. The “water stress” therefore affects not only the countries in the Middle East that are given priority in the WRI Water Risk Atlas. A worrying development can also be observed in regions with intensive agricultural irrigation, such as the western USA, China or southern and western India. A less well known fact is that water is also becoming scarce in Europe, for example in Spain, southern France, Bulgaria, Cyprus and Greece. And even in Germany, regional competition for the resource water is no longer uncommon.
But the availability of water in good quality and sufficient quantity is essential both for the sustainable development of societies and for intact ecosystems. “If we don’t want to leave anyone behind with respect to global water supply, as mentioned by the United Nations in its sustainability goals, we have to consistently use water more than once,” says water expert Engelbert Schramm. “Instead of building dams, which are usually associated with forced resettlement, or tapping the last groundwater resources, some of which renew very slowly, we have to establish wastewater as an additional water resource. This will enable us to significantly reduce the pressure on the natural water cycle.”
Reducing pressure on drinking water reserves – recycling wastewater
“A real water turnaround towards the sustainable use of all available resources is possible and an important prerequisite for the ability to supply water and sanitation on a global scale,” says Martin Zimmermann, water researcher at ISOE. Here, the transfer of the circulation principle to the use of water plays a decisive role. Slightly polluted wastewater from households, for instance from hand basins and showers, can be treated with comparatively little effort and reused for toilet flushing or garden irrigation. “The core idea of a more sustainable use of water is that drinking water is not needed for all purposes. It is important to note that different qualities of treated water can be made available for different needs, ranging from drinking water to water for irrigation” says Zimmermann.
For countries with significant water shortages, the reuse of water offers great potential especially with regard to sanitation . “Well-regulated sanitation not only improves the health situation of the population, but also offers the possibility of agricultural irrigation for the production of food for human consumption or animal feed. Here for example the application of water reuse comes in,” reports Zimmermann. Corresponding resource-efficient technologies for water reuse are being successfully tested worldwide by ISOE.
Technological and social transformations for global water safety
In order to be able to guarantee water safety on a global scale, however, further components are of central importance. “To name three: We must continue to implement and test new infrastructure concepts, provide scientific support for appropriate transformation processes with a view to the cooperation between the actors involved and, for example, make more consistent use of instruments such as water demand forecasts for rapidly growing megacities,” says Martin Zimmermann. Another relevant aspect of water security concerns political decision-makers and their application of research findings and recommendations that include the development of strategies for sustainable water and sanitation. In addition to these technical transformations, society is also called upon to perform a change of mindset if a “water turnaround” is to be successful.
Dr. Nicola Schuldt-Baumgart
Head of Knowledge Communication & Public Relations
Tel. +49 69 7076919-30