Technical specifications

Twin-bore railway tunnel

  • Each tube 9.4 km long
    of which 8,984 m were driven using a TBM
  • Internal diameter: 9.60 m
  • 2 cut and cover sections
    Lengths: 286 m and 115 m
  • 19 cross-passages
    (18 crosspassages constructed using mining techniques,
    1 cross-passage within the sonic boom structures)
  • 2 ventilation shafts, 67 m deep
  • Water pressure up to 9.2 bar

Construction of sonic boom structures at all portals to avoid the sonic boom effect

Construction method

  • TBM tunnelling using 2 EPB shields
  • Shield diameter 11.12 m
  • Operated both in open and in closed  mode
  • Segmental lining, 60 cm thick


  • Tertiary claystone, marlstone, limestone and sandstone

General data

Katzenberg Tunnel
part of the new/upgraded Karlsruhe-Basel railway line
single-track railway tunnel

DB Netz AG [German rail company]
represented by DB Projektbau GmbH
Projektzentrum Karlsruhe

Wayss & Freytag Ingenieurbau AG
as commercial leader of a joint venture

Construction period
August 2003 to March 2011

Construction costs
€ 340 million

Railway tunnel single-track
2 * 9.4 km
Construction Method
TBM tunneling using two EPB shields

Tubbing Production

  • Katzenberktunnel_Tuebbing_E.mp4

The Katzenberg Tunnel is part of the new/ upgraded Karlsruhe-Basel railway line, the so-called Rheintalbahn (Rhine Valley Line), which is a continuation of the Cologne/Rhine-Main high-speed railway line and runs towards the south through the Rhine valley to the Swiss border. In July 2003, Deutsche Bahn AG, the German national railway company, awarded the contract for this project to the Katzenberg Tunnel Joint Venture, consisting of Wayss & Freytag Ingenieurbau AG, Ed. Züblin AG, Marti Tunnelbau AG and Jäger Bau GmbH. The Katzenberg Tunnel is a twin-bore tunnel with a total length of 9.4 km each, of which 8,984 m were driven by TBM. Two 67 m deep ventilation shafts were built inmid length of the tunnels.

For the first time in German railway construction history, two EPB-TBMs were used to construct the tunnels consisting of a single-pass reinforced concrete segmental lining. The geology encountered was characterized by layers of marl and Meletta. With an overburden of up to 120 m, design water pressures of up to 9 bar and water inflows of up to 60 l/s had to be coped with. By choosing 2 EPB machines, which could be operated both fully filled and partly filled with or without compressed air cushion, it was possible to cope safely with the varying soil conditions.

The Katzenberg Tunnel was opened to traffic by an ICE train and a freight train driving through the tunnel tubes. Wayss & Freytag Ingenieurbau, Area Tunnelling, built the third largest railway tunnel in Germany in a joint venture.

The Federal Minister for Transport, Peter Ramsauer and Rüdiger Grube, Chairman of the Board of Deutsche Bahn AG (German Railway), together with Winfried Hermann, Minister for Transport in the Federal Land of Baden-Württemberg, gave the go-ahead for the operation of the new tunnel in Efringen-Kirchen. “It is a showcase project“, explained head of the German Railway, Rüdiger Grube. To avoid the sonic boom effect, all tunnel portals were provided with a cover structure. The Katzenberg Tunnel is part of the new and upgraded section of the Karlsruhe / Basel railway line and is situated in the „Markgräfler Land” on the Swiss border.

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