We are trying to do that at several sites here in Germany, too. The big problem is getting all that water. You can’t take that much from the rivers around - they currently have problems with low water levels due to the heat and no rain. Therefore you can’t take that much water f.e. from the Rhine to fill the Garzweiler holes. The current plan is that this will take several decades
There are a lot of lignite mines, which have been flooded already. During mining ground water is usually pumped out of the mine, to prevent flooding. So if you stop mining and pumping, the mine would flood anyway. However that would also wash out minerals and cause some serious problems on the “shore” of the new lake. So usually it is better to flood it as fast as possible.
The issue is that these mines are among the largest in Europe. Garzweiler as well as Bełchatów. However for Garzweiler we are talking 1/30 of the water the Rhine has near Colonge. It is bad, but certainly possible.
1/30 of the Rhine water near Colonge is massive. That is one of Europes biggest rivers and taking that much amount of water out is serious. We are talking about problems with shipping and water management in the netherlands, increased salinity in the north sea and so on. And if you take a look at the Spree, stopping pumping up the groundwater has its own problems. Berlin is depending on water from the Spree which is coming from pumped up groundwater. Stopping that will change a whole river system that grew over decades.
1/30 of the Rhine water near Colonge is massive.
Sorry, but it is 1/30 of the water which flows past Cologne in the Rhine in a year to fill up the entire Garzweiler mine. So basically diverting the Rhine for a bit more then 12 days. I realize that what I wrote was easy to misunderstand.
But the key here is that the alternative is to keep the pumps running forever. Otherwise you get an acid lake with collapsing walls. Obviously keeping the pumps running also causes massive problems. I am sure they find a solution for Berlin as well.
I saw a model on this: If the drainage water from the open-pit mines stops flowing, the Spreewald upstream from Berlin will evaporate as much water as would otherwise flow into the Spree without drainage… This is bad news for Berlin, which obtains a significant portion of its drinking water from the Spree’s bank filtrate.
Water itself isn’t the big problem. Water in huge amounts in an orderly manner is.
If you simply shut down the pumping stations that currently keep the pits dry by lowering the water table, the pits will fill up with groundwater on their own. However, there are two major drawbacks to this:
1. The pit walls will become unstable and start to slide… a process that could make it impossible to use the lake for a very long time.
2. The inflowing groundwater causes the pyrite found in coal seams to weather into sulfuric acid, which means that the pH of the lakes drops to levels that are hostile to life. This is precisely the problem currently being addressed through liming in the post-mining landscapes of the eastern German states, a process that also consumes a great deal of money and resources.
/edit: Melchior already wrote the same… should have read the comments before. ^^’
I was interested to see this on a map, where exactly it is etc.:
BTW the “Szczerców field” mentioned in the article is labeled “Pole Szczerców” on the map.
The huge mine complex stretches to around 8.5 kilometers in length, with its size so vast it has been visible via satellite imagery. At its peak, huge holes in the earth plunged as deep as 310 meters.
That’s deep.
Also: Bagger!
Leaving the excavator underwater is going to make for some amazing unsettling photos in about twenty years
c/submechanophobia
But where are we going to mine our polish from now? Think of all the dull, unshined shoes…
