Hardly anyone takes notice of them, but without them the Berliners could probably wade through the Spree and say goodbye to Lake Tegel: the Spree locks on Mühlendamm and in Charlottenburg, the Havel lock in Spandau. Manfred Krauss, water expert at the environmental protection organization BUND, paints a bleak picture: If the buildings weren’t holding back the water of Berlin’s two most important rivers, they would be reduced to rivulets.
Anyone who has opened an umbrella in Berlin in the last few days may not believe it: the city is drying up. Out of 530 stagnant pools, pools and ponds, every third is affected by drying out. . At Berliner Wasserbetriebe, desperation is spreading in view of the measurement data: in 2022, significantly less than 400 liters of rain per square meter fell, for example 355.5 liters at the Dahlem measuring point. In the years 1981 to 2010 it was almost 590 liters on average.
The groundwater level is falling. Less water comes over the Spree from the Lusatian lignite mining area because less groundwater is pumped into the Spree there and the lakes in the abandoned opencast mines fill up.
Why the Spree sometimes flows backwards
In summer, the Spree flows backwards between Mühlendamm and Müggelsee when more evaporates in the lake than flows in again. The headwaters of Panke, Tegeler Fliess and Wuhle were dry in the summer of 2022.
In Berlin’s suburban belt there is heavy construction, more soil sealed, water pumped. Overall, Berlin still consumes too much water.
Krauss still has a whole bouquet of complaints about the situation in Berlin’s waters: new buildings erected too close to the banks. Neglected reed protection.ferr. Lame renaturation of the Panke. Garden monument conservators who do not want cleaning reeds in park waters such as the Lietzensee. Decades ago, the Senate handed over the maintenance of small bodies of water to the parks departments of the districts, which have neither the knowledge nor the means to do so. Rainwater contaminated with oil, tire abrasion and dog excrement that flows untreated from the streets into bodies of water such as the Schäfersee.
A legacy that does not fit with climate change
The central problem, however, is a historical development that no longer fits in times of climate change. Krauss: “Previously, people in Berlin and Brandenburg tried to drain rainwater out of the landscape as quickly as possible in order to be able to cultivate crops.” Straight ditches were dug for this purpose.
The same goes on beyond agriculture: The water companies treat 60 to 70 million cubic meters of rainwater annually, but five times the amount of industrial and household wastewater. According to Krauss, this purified “clear water” is still contaminated with nutrients and trace substances such as residues of the pill or painkillers and is fed into the rivers. It will still be a few years before new cleaning stages in the sewage treatment plants at least reduce such problems.
However, the clear water ensures that, for example, bank filtrate can still be pumped along the Havel for drinking water, or at least that there was still water in the lower reaches of Panke and Wuhle in summer.
Administrative confusion inhibits help for Berlin’s water
A jumble of responsibilities, as a senior employee of the water company recently described in the House of Representatives, slowed down renaturation measures or seepage possibilities. Measures such as supplying the Karow ponds with clear water would be financed by the state of Berlin as projects from the state budget. With no prospect of a guaranteed permanent cash flow. The water companies are legally not allowed to use any money from the sewage fees for such meaningful projects.
So how should the slogan of the “sponge city” be implemented, with more seepage, with better use of clear water, with winding and therefore slower-flowing small rivers?
And above all in the interaction of administrations that pull together?
Rescue could be a role model from the Ruhr area, where a water problem was tackled in such a way that it did not sink into the morass of conflicting administrations. A problem that was different, but whose solution points to a path that Berlin could also take. Even if it will be expensive and take decades.
Clear streams instead of cesspools
Since the 19th century, the small river Emscher had become the central cesspool there, all sewage from houses and industry flowed into the Emscher and its tributaries. The reason: You couldn’t build underground channels like in Berlin because of “mining damage” because the ground kept sinking due to mining.
In 1992, the “Emschergenossenschaft” then came up with the plan: We will make the river system free of wastewater. 30 years and 5.5 billion euros later, it was successful, sewage treatment and pumping stations, hundreds of kilometers of sewage pipes were built, the courses of the streams and (largely) the Emscher itself were renatured.
dr Mario Sommerhäuser, head of department at the cooperative, not only electrified the parliamentarians at a hearing in the House of Representatives, but also Senator for the Environment Bettina Jarasch (Greens) when he explained the concept for success: the cooperative includes the many cities and districts in the Ruhr area alongside the state government of North Rhine-Westphalia Westphalia on the supervisory board.
Learning from the Ruhr area?
However, the cooperative can act largely autonomously. Among other things, this meant that the annual average costs of almost 190 million euros over the 30 years were only ten percent above the plan. And although the project was mainly financed from sewage fees, for the people in the Ruhr area they were not at the top of the state.
Berlin, in association with Brandenburg, should think about developing a similar model.
Senator Jarasch: A good approach
Jarasch told the KURIER that the idea of the cooperative was extremely interesting, a good approach to administrative reform. First of all, the water companies would have to be given the legal mandate to take care of renaturation, for example, and thereby receive secure long-term fee income.
In any case, Manfred Krauss, who after decades of dealing with the subject has little hope that the Berlin administration can solve the water problem, was a little more optimistic after the hearing: “The deputies are now asking completely different questions than two years ago.” State of emergency seems to have reached people’s heads.
