The new tunnel guides traffic straight from the mountain into the city centre. Special safety precautions had to be taken before workers were able to begin drilling directly under Cochem’s historic city centre. Surveillance marks and special measuring instruments were installed in buildings located within the danger zone. Probes were used to register changes in the soil during work, allowing experts to intervene at any time. “The distance to the building foundations is mostly between 10 and 15 metres, but in critical areas as little as just 3.5 metres,” reports ALPINE employee Marco Reith. The massive steel structure was overhauled before drilling work commenced in the sensitive area.
The drilling work took place in open and closed mode – the machine dug in “open mode” up to a certain point, then it worked in closed mode. This means that near the bore head a soft soil mixture is used to facilitate drilling. This is necessary because in some tunnel boring sections there is nothing but soft rock between the tunnel shaft and the ground surface above. The machine was operated day and night from the middle of August to the beginning of October, drilling the 500-metre long route through the “Oberstadt” district of town. Following the breakthrough in November 2011, the team breathed a sigh of relief and literally saw “light at the end of the tunnel”. “The drilling work was completed without any complications and we were well below the level of subsidence expected,” Marco Reith is pleased to account.
The massive steel structures were the source of a number of extremely tense situations in the historic tunnel. In November 1948 there was a coal dust explosion in the driver’s compartment of a Type 50 2059 steam engine in the middle of the tunnel. D train 21 from Koblenz to Paris had 650 passengers on board. The entire driver’s compartment went up in flames after a jet of flame escaped from the firebox.
The locomotive driver was no longer able to touch the brake valve and it seemed as if the train was unstoppable. In a spectacular feat the locomotive driver climbed out of the driver’s compartment and onto the metal siding of the steam engine, where he was able to reach the front air valve and managed to bring the train to a stop at the end of the tunnel. Locomotive engineer August Vochtel of Trier received the Medal of Bravery from the French Governor for saving the lives of all of the passengers on board the train!
The Kaiser-Wilhelm-Tunnel cuts through a meandering loop of the River Moselle, thus sparing the Moseltalbahn railway line from an incredibly long detour on the route from Trier to Koblenz. The first trains are scheduled to travel through the tunnel on completion at the end of 2012. Then the old Kaiser-Wilhelm-Tunnel will be renovated.
By the way: You won’t see the “light at the end of the tunnel” if you stand at one end of the tunnel and try to look through it. The Kaiser-Wilhelm-Tunnel may be as straight as an arrow, but it ascends a total of 14 metres during the course of its 4,205-metre long route.
>> Press release covering the tunnel break through
Tunnel boring machine at „New Kaiser Wilhelm Tunnel“
„New Kaiser Wilhelm Tunnel“ broken through
Videos source: YouTube
