Hydrogeology

Lusatia Excursion

For students of hydrogeology at the TU Berlin we offer a three-day excursion to Lusatia

The increasing water shortage in Brandenburg has become a much-discussed topic in the news and is becoming a central research topic at our department. In addition to climatic changes, the consequences of decades of lignite mining in the Lusatian region influence the development of a sustainable water use concept.

During a guided tour of the Welzow-Süd open-pit mine, the students learn about the technical mining processes in an active open-cast lignite mine and the applied dewatering measures.

The tour of the overburden conveyor bridge F60 is a highlight of the excursion. The process of actively flooding residual opencast mining holes can be studied using the example of the Cottbus Eastern Lake, which will be the largest artificially created lake in Germany once flooding is complete.

Schedule of the Lusatia Excursion 2023

Impressions from the Lusatia Excursion from September 2022

Lusatia Teaser

© Jan Oestreicher

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The cinematic impressions were recorded at places visited on the Lusatia excursion and show the development of various post-mining landscapes. At sites where the land has already been restored, such as the Schlabendorfer See near Wannichen shown at the beginning, an impressive natural landscape has developed since the end of open-pit mining in 1991.

Schlabendorf Lake

There, the well-known wildlife filmmaker Heinz Sielmann and his foundation have acquired an area of 3300 hectares and created a nature reserve which is home to thousands of migratory birds.

At the same time, the ongoing work on behalf of the LMBV to renaturalise the lake can be observed at the site. In the Schlabendorf marina (as of July 2021), the special ship "Barbara" is moored, which uses a special device to apply lime to the lake. By injecting lime powder into the water body, the water quality is to be improved and at the same time the iron dissolved in the lake water is to be precipitated.

Adventure Trail near the Gut Geisendorf

At the "Gut Geisendorf", an adventure trail has been set up in the renaturalised area, leading to the restored hills of the former Steinitz-Geisendorf end moraine.

During the active mining phase, the Welzow-Süd (Welzow-South) open-pit mine approached to within close proximity of the "Gut Geisendorf" (Geisendorf estate). The village of Geisendorf lay within the approved mining area and resettlement took place to Neupetershain.

As part of the recultivation measures, the Steinitz spring, which existed before mining began, was also restored. With 230,000 cubic metres of clay, the original underground well was remodelled and is now fed again by precipitation water, so that a natural spring discharge should take place.

Flooding of the former open-pit mine Cottbus-Nord

An impressive project is the flooding of the Cottbus-Nord open-pit mine. More than 80% of the open pit is to be flooded with water from the Spree River and the remaining water inflow is to be achieved through the rising groundwater. Flooding could start in 2018 and is expected to be completed during the 2020s.

The footage shows that the north rim tube is already filled with water, which has a trench depth of about 20m. As flooding progresses, areas of the inner dump are slipping and partially filling the trench. Once flooding is complete, Germany's largest post-mining lake will have been created with a shoreline of 26 kilometres.