The JV of German contractors Bilfinger Berger, Wayss & Freytag and Züblin has been awarded a US$498M contract to construct 3.2km of 7.3m i.d twin tube rail tunnel on Cologne’s new north-south metropolitan railway.

The running tunnels will be bored using two TBMs, whilst six stations will be mined along the alignment. The route, that links the city’s south with it’s main railway station, takes the tunnels under Cologne’s historically sensitive central buildings. Work is due to start this year and ground stabilisation techniques including high pressure injection and freezing are foreseen. The contract was awarded by the client, Kölner Verkehrs-Betriebe AG, who hope to see the line operational by 2010.