Saxony is struggling with ever-decreasing groundwater – experts warn of a long-term crisis

Saxony has been struggling with declining groundwater for a long time. The situation has worsened further this year. “Currently, at around 88 percent of our 550 measuring points, groundwater levels are on average a good half a meter below the usual level,” said Andy Philipp, water expert at the State Office for the Environment, Agriculture and Geology, to the German Press Agency.

For comparison: a year ago, 81 percent of the measuring points were 37 centimeters below the limit. After a brief relief at the end of 2021/beginning of 2022 and in the winter of 2023/2024, we have reached a low point again.

Groundwater levels have been falling since 2013

«Groundwater is an element of the water balance that we know quite well because we have a large number of measuring points. The groundwater levels have been falling since 2013. There has been no long-term recovery so far, especially no sustainable recovery," emphasized the expert. There is also a shift in dynamics. In the past, a significant proportion of precipitation fell as snow, especially in mountainous areas. When the snow melted, the groundwater reservoir filled up. In recent years, however, this effect has become less and less common.

“We continue to see a decreasing trend in the average groundwater levels. Significantly low levels and the persistence of the situation are unusual in a long-term comparison,” said Philipp. Now the question arises as to whether all of this is still within the natural range of fluctuation or whether it has led to a fundamental change. Direct observation of groundwater recharge is only possible to a limited extent. “We know the groundwater levels well. But groundwater is not static, it flows underground. This means it cannot be recorded directly.”

“Lysimeter station” in Brandis provides conclusions

The state office in Brandis (Leipzig district) maintains a so-called lysimeter station for data on the water cycle. It consists of 28 cylinders approximately three meters high, open at the top and closed at the bottom - the lysimeters. What is measured is how precipitation seeps through different types of soil. “Something has now emerged that has never existed before. Even a large number of heavy soils, which otherwise have a large storage capacity, remain without seepage water. In other words: Even though it rained above, nothing came down below all year round.

Philipp assumes that an interplay of several factors is responsible for this development. In addition to a decrease in precipitation, this was also caused by significantly higher evaporation. As the temperature in the atmosphere increases, there will also be more localized heavy rain. “It makes a difference for the water balance whether 50 liters per square meter falls as land rain over the entire weekend or within an hour as heavy rain. Because then it can hardly seep into the ground and flows off to the surface.

Trees can no longer draw enough water

Philipp also discussed the effects. “There are broad effects, even if they are less relevant and noticeable in certain areas.” The lack of groundwater would be visible, for example, when trees were attacked by bark beetles. “Spruce trees can no longer produce resin when there is a lack of water. But this is needed to close the bark beetle drilling sites. And falling groundwater levels also worsen the availability of water in the soil above groundwater. Even deep-rooted deciduous trees would sometimes no longer be able to draw enough water.

Groundwater is also crucial for the drinking water supply, emphasized Philipp. Around 70 percent of drinking water in Germany comes from groundwater or spring water and bank filtrates. In Saxony it is 60 percent because the Free State has a comparatively large number of dams. Last but not least, it is important to take the water ingredients into account. Nitrate pollution is a problem in northern Saxony, for example. As groundwater declines, the technical and financial effort to purify the water increases.