Disillusionment among supporters of a tunnel solution for Bamberg. Many in the city council had apparently hoped that an underground double tube would swallow rail noise completely. But this is not the case, as Ursula Sowa (GAL), among others, was disappointed to discover. Even with a tunnel, a third of freight train traffic would still roll above ground, albeit in whisper mode from 2025 onwards.
On Friday, the railroad and the city of Bamberg had invited to the fifth meeting of the coordinating group for railroad expansion. Both sides are still avoiding the conflict-laden topic of costs. The figures in the three-digit million range are to be determined for three variants in a next step and published at the end of March, probably after the local elections. But even so, the city gained important insights in the process of approaching the largest transportation project in Bamberg’s recent history.
Two figures were used by Klaus-Dieter Josel, Group Representative of Deutsche Bahn, to illustrate the effects of two fundamentally different variants. If a four-track extension is built, 18,000 of the 20,000 people who live near the tracks will benefit from the possibilities of innovative noise protection. This is an improvement of 5,000 compared to the current situation, in which the limit values are only complied with for 13,000 residents. The number of people protected from rail noise would also increase with tunnel construction, but not as much – from 13,000 to 17,000. The reason is the lack of noise protection north of the station, where the railroad line would run underground.
For Josel, the first figure in particular was good news. It means that, despite all the prophecies of doom, innovative noise protection will achieve its goal – an urban-compatible rail expansion – at least that’s how the German transport company sees it.
In its calculations, it relies primarily on the nationwide introduction of so-called quiet freight trains with plastic brakes, to which the federal government has committed the railroad by 2025.
In addition, so-called rail web dampers are to be used in Bamberg and the tracks are to be ground regularly. All this means that the "monster walls" feared by many will not be built in Bamberg now again "shortened could be built – to a depth of three meters. They are also to be kept in glass where the view of the city’s towers falls: at four points.
240 million is too little
Since Friday, the realization that a tunnel under Bamberg is technically feasible has also been official, so to speak. According to the engineers, it would have to be built using the mining method, i.e. with a tunnel boring machine. This is how the two tubes with a maximum depth of 25 meters under the station could be broken through solid rock. In addition, an open construction method places much higher demands on the control of groundwater flows running from east to west.
On Friday, Deutsche Bahn did not want to give any details about the costs of the two-and-a-half-kilometer tunnel through Bamberg. At least this much was learned from Josel’s mouth: 240 million euros, a figure that was last mentioned by the citizens’ initiative Bahnsinn Bamberg, appears to the railroad as "clearly too little". In addition fits, which announces at present from Leipzig. The cost of a similarly long double tube under construction there is 960 million euros.
Even without the cost issue, the tunnel solution, which for a time was seen as the ideal solution, has received a few scratches in the paint as a result of the study. Thus, according to calculations of the railroad and despite an underground west branch, it is far from possible to banish all wagons in Bamberg under the ground. 71 freight trains would have to continue to run above ground through Bamberg in the future, 40 of them at night, because of the station’s function as a hub.
Not even visually does the tunnel seem to be the panacea that some had hoped for: Because of the 500 meter long ramps, the tunnel also needs noise protection. "Up to the atrium, the variant would therefore hardly differ from any other", A municipal traffic planner described the dilemma.
The importance of noise protection is also shown by the traffic volume figures for 2025: Overall, the railroad assumes a significant increase in train frequency in Bamberg. Of the 400 or so trains that will then pass through Bamberg, 250 will be freight trains – that would be double the number today.
Also in terms of construction time, the tunnel is likely to bring the greatest burdens. The realization of the mining tunnel construction would take eight years, the new construction in the existing structure five, the eastern bypass four years, said railroad planner Reiner Gubitz.
If you believe the decision-makers at the railroad, there is currently no favorite. Bamberg’s eastern bypass – the bugbear of conservationists and many residents in Bamberg-Ost, Lichteneiche and Gundelsheim – is also still in the running. This has mainly to do with the costs. Even without precise figures, it is clear that building a new line on a greenfield site is significantly cheaper than upgrading the line "on wheels" right through the city.
For the Bahnsinn initiative, it is therefore clear that an eastern bypass can only be considered completely underground. Spokesman Robert Bartsch also thinks it is essential to continue thinking about this variant because he does not like to believe the railroad’s promises about innovative noise protection. "Railroad tries to bring down walls with statements of intent. We don’t go along with that."