Is there enough drinking water?

Will Germany soon be running on dry land? This question is posed by “Der Spiegel” this week, the cover topic is water scarcity and the high temperatures. This shows that the shortage of drinking water is high on the media’s agenda in these hot summer weeks. In fact, groundwater levels in many regions of Germany and Europe are lower than ever before. For weeks, temperatures in Germany have been high and the rain has failed to appear. “Our water resources are coming under increasing pressure,” the German government wrote as early as mid-March in its “National Water Strategy”.

70 percent of drinking water in Germany is sourced from groundwater and spring water, the rest from surface-affected waters such as reservoirs or bank filtrate.

Since the beginning of the 2000s, i.e. within only 20 years, Germany has lost groundwater of the volume of Lake Constance, say researchers from the Potsdam Institute for Climate Impact Research. The main reason for this is climate change, which is altering the weather. It doesn’t rain less, but the precipitation is distributed differently, and when it does rain, it is often so heavily that the water only runs off at the surface and cannot seep into the soils that have dried out from dry periods. The increasing sealing of surfaces does the rest. At the same time, more water evaporates.

Conversely, the water demand of humans and nature is increasing because climate change is leading to longer periods of heat and drought. Every person in Germany consumes a total of 125 litres of water per day, and on hot days it can be significantly more.

Only about 30 percent of water consumption is used by private households and small businesses; large-scale consumers are mainly industry and agriculture.

Dry periods will become more frequent and longer in the coming years. Especially in the north and east of Germany, climate change is leading to falling groundwater levels. The Federal Environment Agency therefore no longer refers to Germany as a water-rich country, as this sends the wrong signals. In times of climate change, water becomes “more valuable than oil”, Bavaria’s Prime Minister Markus Söder recently said. That is why the Free State is spending 100 million euros on water supply and groundwater protection this year alone.

Drinking water is a basic foodstuff that is treated, filtered and strictly controlled for pathogens and pollutants. But as long as drinking water costs so little in Germany, it is not considered valuable either and is often thoughtlessly wasted. And why should we limit ourselves when others consume much more?

A careful use of drinking water is not only important to avoid acute shortages. More conscious consumption helps to save water. But what can individual consumers do in the short term to save water? In the household and garden, there are numerous ways to quickly make an impact without much effort.

• – Toilet flushing: About a quarter of the daily water consumption is needed for toilet flushing, older toilets use 9 to 14 litres of drinking water per flush. According to the Federal Environment Agency, a flush tank with an economy button can save about half that amount. Reducing water consumption from 12 to 6 litres per flush saves about 30 litres per day.
• – Showering: With an economy shower head, about half the water can be saved without sacrificing comfort and hygiene: Instead of 12 to 15 litres of water per minute, the economy shower head gets by with 6 to 9 litres. A full bath, on the other hand, consumes many times as much water, especially in summer.
• – Washing machine: The older the washing machine, the higher the water consumption. While a new machine consumes 40 to 50 litres (and less electricity) per wash cycle, a ten-year-old washing machine needs about twice as much.
• – The same applies to the dishwasher: modern appliances consume about eight litres per wash cycle, while 12 litres is considered a lot today. Of course, only run both appliances when fully loaded.
• – Watering the garden: As a general guideline, 15 to 25 litres of water are needed per square metre of garden area per week. However, the water does not have to come from the tap. Rain harvesting barrels or cisterns can cover part of the water requirement. On the other hand, you should only water in the early morning or in the evening, when evaporation is at its lowest, and always aim at the root ball of the plants and not at the leaves; this reduces evaporation.
• – Car washing is not necessary in the summer months and should, if necessary, only be done in modern car washes and not at home in the yard.