Since 12 December 2022, the last two open shafts of the former Concordia colliery in Oberhausen have been filled with concrete. In preparation for this, THYSSEN SCHACHTBAU has carried out extensive excavation and conversion work in the shafts and above ground over the past 30 months.
Up to now, Shaft 2 and Shaft 6 as well as a small part of the mine workings had been kept open even after coal production ceased in 1968. Mine water was pumped to the surface via the shafts and discharged into the Emscher until the end of September 2022.
This is now history. Over the next few years, the mine water will rise as planned to about -620 metres and then flow underground to the mine water drainage system at the former Walsum mine in Duisburg. There it will be pumped to the surface and discharged into the Rhine. For the Emscher, the end of discharge represents an important step in the conversion to a natural watercourse.
After the Auguste Victoria site in Marl and Haus Aden in Bergkamen, this is already the third site that THYSSEN SCHACHTBAU is converting on behalf of RAG Aktiengesellschaft as part of the eternal task of mine water drainage. In the next few weeks, the Zollverein and Amalie sites in Essen will also be prepared to the point where they can be backfilled and no longer discharge mine water into the Emscher.