Mine water sewer Ibbenbüren – Construction work for mining facilities

Long-term infrastructure for mine water management

Following the end of coal and anthracite extraction at the Ibbenbüren mine in Germany, this project creates a 7,4-kilometer mine water sewer system for the long-term management of rising mine water. The new infrastructure transports mine water by gravity to the Gravenhorst wastewater treatment plant. The scheme comprises two tunnel drives with lengths of 3.230 metres and 3.870 metres, excavated using two variable-density tunnel boring machines (VD-TBMs). A 230-metre cut-and-cover section with bored pile shoring and a 30-metre launch pit formed the western access to the underground works.

A major engineering component was the construction of a central shaft with a depth of 75 metres and an inner diameter of 30 metres, serving both as the reception shaft for the western TBM and the launch shaft for the eastern drive. Mine water is collected through the segmented tunnel lining and directed into a prefabricated invert channel, enabling controlled drainage from the mine.

Depending on operational requirements, annular gaps were backfilled with pearl gravel or two-component mortar. Modernization of the existing 100-metre deep Oeynhausen Shaft 1 was carried out after TBM breakthrough. The completed system provides a reliable long-term solution for mine water management while ensuring gravity-driven transfer to the treatment facility.

Scope of Work

• Tunnel construction using TBM technology 
• 230 m cut-and-cover tunnel section 
• Central shaft creation
• Refurbishment of the Oeynhausen shaft 
• Installation of segmental lining systems 
• Backfilling and drainage work