CZ/SK verze

Zooming through the Ore Mountains: An Exclusive Interview on the Record-Breaking Rail Tunnel Connecting Czech Republic and Germany

Zooming through the Ore Mountains: An Exclusive Interview on the Record-Breaking Rail Tunnel Connecting Czech Republic and Germany
photo: RAILTARGET/Zooming through the Ore Mountains: An Exclusive Interview on the Record-Breaking Rail Tunnel Connecting Czech Republic and Germany
22 / 07 / 2023

RAILTARGET presents an exclusive interview with Prof. Dr.-Ing. Arnd Stephan, who works at the Technical University of Dresden. He is also the Director of the Institute of Railway Technology Prof. Stephan is involved in the design of the longest railway tunnel in the Czech Republic and Germany and provided our editorial team with exclusive information. Do you know how this unique technical structure is designed and what all the engineers have to take into account?

Professor, the planned Berlin-Prague-Vienna high-speed railway line will run between Dresden and Ústí nad Labem through the 30 km-long Erzgebirge tunnel. What is the current status of the preparation and planning of the longest railway tunnel in Germany and the Czech Republic?

I would like to start by saying that I am personally very excited about this project. It is not only an excellent, almost unique technical task for us engineers but, above all, a European transport project that will bring the inhabitants of our countries closer together on many levels. We can already see this in the current planning phase, which is being organised bilaterally between the Czech Republic and Germany.

And people from both countries are working together on this. After initial considerations in early 2010, which included the project in the German Federal Transport Infrastructure Plan (Bundesverkehrswegeplan), a legal requirement for it to have any chance of being implemented, extensive planning and survey work is now underway. The German side has an important land-use procedure in which the possible route alternatives are comparatively evaluated in principle, resulting in the identification of a preferred alternative for subsequent detailed planning. In parallel, extensive geological investigations are currently being carried out using state-of-the-art scientific methods. For the first time, the Ore Mountains are being mapped completely underground in this area. The main objective is to identify potential geological risk areas for the tunnel construction. The findings will then be directly incorporated into the route evaluation. In addition, preliminary engineering planning is already underway, particularly concerning aspects of rail traffic and integration into existing rail networks, as well as the electrical supply of the tunnel route. Our university is also involved in this, which we are very proud of. These basic plans are very important because, after all, the facility is to operate efficiently for many decades.

What criteria are relevant for the route? When will these criteria be used to determine the best, i.e., preferred, route option?

In spatial planning, the so-called spatial permeability is assessed, i.e., the question of where the route can be routed and what effects it can be expected to have on people and the environment. The technical and economic aspects of the construction and subsequent operational phases also play a role, but not only these. The aim is ultimately to find the best compromise. It may turn out that the cheapest option is not the preferred one, but the one with the fewest obstacles in the area but comparable benefits.

The Ore Mountains are geologically very diverse. What do you have to take into account as opposed to other transport structures? Are there any surprises to be expected in this respect, and should delays in planning the construction be taken into account?

Yes, of course, there will be surprises. But the modern survey methods already mentioned, with a large number of test holes and electromagnetic surveys of the strata, aim to identify these risk areas as far in advance as possible, even if this is only possible on a rough scale. Partial problems may occur, but correcting them is easier than changing the entire route. Experience with the construction of new large Alpine tunnels in Switzerland, Austria, and Italy has shown that these risks can be taken into account already in the construction planning through appropriate reserves. The rule of thumb is, it is better to research and plan thoroughly in advance than be caught unprepared later.

Will the preferred option also include a specific cost estimate?

Absolutely, because studies in the different planning phases always update previous cost estimates based on the new planning and preparation phase. The decision on the preferred route is also made based on economic considerations. In addition, an updated cost estimate on an ongoing basis is absolutely essential because projects of this magnitude must, of course, go through the parliamentary approval process in the Bundestag.

How do you assess the cooperation between the Czech Railway Administration and DB Netz AG so far?

According to what we know about our contacts with our German and Czech colleagues, the cooperation is developing well and is based on trust. It should be remembered that railways and especially rail network operators are national "domains" in their historical development, certainly with different technological approaches and sets of rules. In cross-border projects, these worlds come into direct contact, and it is always a question of how many national specificities will eventually be reflected in a joint project... In the end, however, the goal is to build a well-functioning overall system between Dresden and Ústí nad Labem, not two half-tunnels that meet at the border in the middle. It also applies to the subsequent long-term operational management and maintenance. In particular, who is responsible for what, and what are the technical and operational solutions? It always requires compromises on both sides for the best long-term solution. Because in the end, it is essential for people on both sides that the railway is fast and reliable.