Wayss & Freytag Ingenieurbau and Züblin receive contract to construct new mine water drainage tunnel in Ibbenbüren

11 October 2021 11:30 - Wayss & Freytag Ingenieurbau AG
Wayss & Freytag Ingenieurbau and Züblin receive contract to construct new mine water drainage tunnel in Ibbenbüren
  • More than 7 km of tunnelling
  • Contract value in the three-digit million range

Frankfurt/Stuttgart, 11 October 2021 - On 4 October 2021, RAG Aktiengesellschaft awarded a bidding consortium consisting of Wayss & Freytag Ingenieurbau AG (50%, technical lead) and Ed. Züblin AG (50%, commercial lead) the contract for the construction of a new mine water drainage tunnel for dewatering the Ibbenbüren mine - one of the last German coal mines - which was closed down in 2018. The contract has a construction volume in the three-digit million range; the multi-year construction work is scheduled to start in November of this year.

From the end of 2024, the approximately 7.4 km long tunnel will drain off the mine water from the former mine, which has been rising in a controlled manner since the deep dewatering system was shut down. The tunnel, with an internal diameter of 3.6 m, will be excavated in two parallel sections by two tunnel boring machines from two access points. For this purpose, a 250 m long section will be excavated as a launching pit and a 70 m deep central shaft with an internal diameter of 32 m will be excavated. The tunnel will be constructed with a precast segmental lining and an invert channel to drain off the mine water. In addition, the existing mining shaft Von-Oeynhausen-1, which is partially filled below the connection of the new tunnel, is to be reinforced. The new drainage tunnel will be connected to it at a depth of 100 m, via which the mine water will ultimately be led to the treatment plant in Gravenhorst.

Wayss & Freytag Ingenieurbau AG

With over 140 years of tradition, Wayss & Freytag Ingenieurbau AG is one of the leading German construction companies that realises high-quality and demanding construction projects. The company is primarily active in the German civil engineering market and the international market for tunnel construction.  

Ed. Züblin AG

Ed. Züblin AG, headquartered in Stuttgart, employs more than 13,000 people and is one of Germany's largest construction companies with an annual output of around €4 billion. Since the company was founded in 1898, Züblin has been successfully realising demanding construction projects in Germany and abroad and is today the leading brand for building construction and civil engineering within the Strabag Group. The company's range of services covers all construction-related tasks - from complex turnkey construction, civil engineering and tunnelling to construction logistics, building maintenance, special civil engineering, timber or steel construction. In recent years, Züblin has driven forward the topics of digitalisation, LEAN. Construction and sustainability and - supported by the many years of expertise of its Central Engineering Department - is also increasingly offering integrated planning and construction from a single source as a general planner.

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