This report seems to be a bit one-sided. They say the lakes will be used as reservoirs for rivers like the spree. The issue is that the spree was feed for years with excess water from the old mines which had to pump the water out. Now they don’t pump water anymore to fill up these lakes and some parts of the spree run low on water during summer. The water table fell a lot over the last 10 to 20 years in Berlin. I’m not sure what exactly contributed to this situation overall. But they had plans to pump water from the Elbe into the Spree to help out with the situation. But cities downstream are not happy about the situation. For me this feels like a somewhat similar situation to the Colorado River situation with the upper and lower basins.

https://www.rbb24.de/panorama/beitrag/2026/07/wasser-mangel-...