PORR to build Poland’s longest railway tunnel

Complex transport infrastructure – including a high-speed rail network – is being built around the new main airport located between Warsaw and Łódź. Now PORR has been awarded the tender for the construction of a railway tunnel in Łódź. “The high-speed railway line will bring Warsaw closer to Łódź and is therefore an important building block in expanding Poland’s transport infrastructure. The size and technical complexity of this project is unprecedented on the Polish market. That’s why we’re especially pleased about the trust that CPK has placed in us by awarding us the contract for the tunnel. We’re aware of what a responsibility this is”, said PORR CEO Karl-Heinz Strauss. The project will be completed within four years.

The approximately 4.6km-long tunnel, which runs from the “Retkinia” launch shaft to the “Fabryczna” exit shaft in Łódź, is the longest and widest railway tunnel in Poland to be bored in a single section. This also makes it one of the most technically demanding elements of the “Y” railway line. The tunnel is being excavated using a TBM (tunnel boring machine) weighing approx. 3,200t with a 14m-diameter cutterhead. The route has double tracks and trains will be able to travel at speeds of up to 160km/h in both directions.

The contract also includes the necessary operational infrastructure for the tunnel, the shafts and the railway line. As part of the project, PORR will build five supply shafts along the tunnel route. It will also realise the inner shells of the launch and exit shafts, which are currently being built as part of a separate contract. In terms of railway technology, the tunnel will be equipped with water and wastewater systems, electrics, telecommunications and fire protection. The project also includes road works and final site development in the vicinity of the shafts.

Slab Track Austria used for the first time in tunnel in Poland

The tunnel is suitable for speeds of 160km/h thanks not only to the structure itself but also a special superstructure. PORR is using the Slab Track Austria technology it developed and patented; it’s the first time it is being applied in a railway tunnel in Poland. In contrast to conventional superstructures, in which the rails are attached to sleepers lying on a layer of ballast, Slab Track Austria technology uses a prefabricated concrete slab as a base. Due to its long service life, stability and track accuracy, as well as the comparatively low noise and vibrations caused by passing trains, this technology can be used on high-speed lines at speeds of up to 400km/h.

Major tunnel projects in Poland completed

To date, PORR has completed several major tunnel projects in Poland. These include the S3 Bolków-Kamienna Góra tunnels, which opened to traffic in July last year, and the TS-26, which at around 2,300m is the longest non-urban tunnel with hard rock tunnelling and was built using the New Austrian Tunnelling Method (NATM). PORR also built a tunnel under the Świna Strait, which connects the islands of Usedom and Wolin in Świnoujście. In addition, it widened a historic railway tunnel in the Lower Silesian Voivodeship, whereby the tunnel-in-tunnel method was used for the first time in Poland. This method allows work to be carried out while maintaining active railway traffic.

Piotr Kledzik, CEO of PORR S.A.: “PORR has already built dozens of kilometres of railway tunnels in Europe, including Poland. Our team consists of experienced engineers who are not only familiar with state-of-the-art technology but can also implement it effectively in dense urban and geologically challenging conditions. And this is exactly the kind of challenge we face in this project. I’m certain that our team’s expertise, technical precision and responsibility will guarantee the smooth, safe and timely completion of this project.”

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