The Ceneri Base Tunnel (CBT; ) is a Swiss railway base tunnel in the canton of Ticino. It passes under Monte Ceneri between Camorino in the Magadino Flat and Vezia near Lugano; it bypasses the former high-altitude rail route through the Monte Ceneri Tunnel. It is composed of two single-track tunnels, each long. It is part of the New Railway Link through the Alps (NRLA) project for faster north-south rail links across the Swiss Alps.
An exploration tunnel near Sigirino was excavated between 1999 and 2003 to gain geological data on the rock formations at the Ceneri Base Tunnel's level. Based on those data, it was decided to excavate most of the tunnel with traditional blasting methods and only drill a small part using a faster tunnel boring machine (TBM). Both the CBT and Gotthard Base Tunnels were built under contract from the Swiss Federal Government by Alptransit Gotthard AG. Construction of the two single-track bores started during March 2006. The official start of the CBT's construction phase was celebrated on 2 June 2006 with the laying of a foundation stone. The final breakthroughs took place on 21 January 2016 (west tube) and 26 January 2016 (east tube). Rail service started on 4 September 2020 and was operationalised for freight in December 2020.
On opening, the Ceneri Base Tunnel has become an important southern feeder for the Gotthard Base Tunnel as the existing, proportionally steep and curvy track over Monte Ceneri is not suitable for high speeds or heavy freight trains. Another feeder is the Luino link along Lake Maggiore which is about to be upgraded by Italy in prospect of the opening of the Gotthard Base Tunnel. Both links meet in the Magadino Flat in the future Camorino Node (). The CBT will ease local train traffic, mainly between the two major cities Locarno and Lugano but also between Bellinzona and Lugano. Travel time on the TILO, an S-Bahn, from Locarno to Lugano dropped from 50 to 22 minutes.
History Background
The Ceneri Base Tunnel is the lowest of the routes through the Ceneri axis and connects Camorino in the Magadino Flat to Vezia near Lugano. It allows traffic to bypass the conventional high-level railway running through the historic Monte Ceneri Tunnel. It forms only one element of a wider effort, commonly referred to as the New Rail Link through the Alps (NRLA) programme, which is being developed by AlpTransit Gotthard AG (ATG), a wholly owned subsidiary of the Swiss Federal Railways (SBB). When it became operational in December 2020, the Ceneri Base Tunnel began working together with the longer Gotthard Base Tunnel to significantly shorten the journey times between the Northern Swiss city of Zürich and the Northern Italian city of Milan by providing a flatter route for freight and passenger trains than previous conventional lines."Ceneri Base Tunnel." railway-technology.com, Retrieved: 10 June 2018."SBB prepares for Gotthard base tunnel opening." Railway Gazette, 1 May 2015.
The Ceneri Base Tunnel carries a pair of parallel bores, each containing a single-track, set apart from one another and connected by cross passages at evenly spaced intervals of . Stretching between the towns of Camorino and Vezia, it possesses a total length of ; the eastern bore has a length of and the west bore is long. An operations center controlling ventilation and logistical activities has been constructed at Sigirino. Operationally, the Ceneri Base Tunnel was anticipated to be used by in excess of 300 trains each day travelling in both directions. It has been furnished with ETCS Level 2 signalling, allowing for trains to traverse it at speeds of up to ."Thales awarded Ceneri Base Tunnel signalling contract." Railway Gazette, 16 September 2016. Although the technical maximum speed is through the Ceneri tunnel, the maximal authorized speed has been reduced to for ecological and economical reasons, while the operating speed of passenger trains is restricted to in order to accommodate the freight traffic, with the possibility to accelerate up to 230 km/h in case of delay.
For handling emergency situations in the Ceneri Base Tunnel, the Swiss Federal Railways has acquired a fleet of dedicated rescue trains; these are equipped with specialised fire fighting equipment and other useful facilities, such as independent air supplies."SBB orders rescue trains." Railway Gazette, 7 February 2016.
The Ceneri Base Tunnel was approved in July 2001 by the Swiss Federal Council, clearing the way for detailing planning activity to proceed. Further Parliamentary approval of the selected route for the tunnel was received in 2003, and the first funds towards construction were released during 2005."Ceneri tunnel start." Railway Gazette, 1 August 2005. During April 2007, AlpTransit Gotthard AG awarded a Sfr85m ($91.52m) contract for the construction of the first underground element of the tunnel to Consorzio Monte Ceneri (CMC) JV, a consortium of CSC, Lugano, Frutiger, Thun, Rothpletz, Lienhard & Cie, and Aarau. During June 2009, the Board of Directors of AlpTransit Gotthard AG announced that it had awarded the principal contract for the tunnel's construction to the Consorzio Condotte Cossi consortium. At the time, the tunnel was expected to be operational by December 2020. This contract was valued at Sfr987 million ($1.6 billion). The estimated total cost for the Ceneri Base Tunnel is Sfr2.4 billion ($2.58 billion).
Construction
During June 2006, construction work on the tunnel officially commenced. In November 2008, the excavation of a adit tunnel was completed, involving the excavation of of hard rock. A tunnel boring machine (TBM), provided by Robbins Company and equipped with cutters, was used to bore the adit tunnel over the course of ten months during which it advanced at a rate of per day."Ceneri Base Tunnel." therobbinscompany.com, Retrieved: 10 June 2018. During the spring of 2010, work commenced upon the boring of the Ceneri Base Tunnel itself. During March 2010, it was announced that blasting had begun on the main drives of the twin-bores."Ceneri base tunnel blasting begins ." Railway Gazette, 30 March 2010. By the end of the year, the rate of tunneling had reportedly attained its full speed. A combination of conventional drilling and blasting techniques were used to bore approximately of the tunnel (including the two main tubes and access tunnels), while the remainder was bored using a TBM.
Breakthrough in the west tube between Sigirino and Vezia occurred on 17 March 2015."First Ceneri base tunnel breakthrough." Railway Gazette, 18 March 2015. Breakthrough in the east tube between Sigirino and Vezia occurred on 30 March 2015. On 21 January 2016, breakthrough was achieved in the west bore between Sigirino and Vigana, while the breakthrough in the east bore between Sigirino and Vigana occurred on 26 January 2016. That same day, it was announced that the excavation process had been completed, and the installation of railway infrastructure was the next major stage of the work. During February 2017, the final concrete block was placed in a ceremony marking the tunnel becoming structurally complete."Ceneri rail tunnel moves closer to completing new alpine rail link." thelocal.ch, 8 February 2017.
During August 2013, the Mons Ceneris Consortium, headed by Mancini & Marti, was awarded a Sfr96 million ($103.36 million) contract to provide railway track and logistics for the tunnel. That same month, the Cablex-led CPC Consortium won a Sfr129 million ($138.89 million) contract to provide railway systems and overall tunnel co-ordination services. The planning, supply, installation and commissioning of the tunnel control systems, which are to be controlled from a control centre at Pollegio, has been contracted to Tunnel Control Systems. The awarding of these contracts was not without controversy; a pair of appeals were subsequently upheld by the Federal Supreme Court of Switzerland regarding the awarding process. At one point, it looked as if the completion of the Ceneri Base Tunnel may be delayed as a consequence of legal disputes."Ceneri Base Tunnel: two-year delay possible." tunnel-online.info, Retrieved: 10 June 2018."Ceneri Base Tunnel: Swiss Supreme Court confirms Railway Infrastructure Awards." tunnel-online.info, June 2014. However, the dispute was settled during September 2014, which unblocked the awarding of contracts as well as allowing for work to proceed."Ceneri base tunnel dispute resolved." Railway Gazette, 14 September 2014.
During 2017 the installation of the track, electrical supply cables, telecommunications and radio systems, automation systems, overhead lines, and various safety and control systems commenced. During August 2017, the first sections of ballastless track were laid in the northern end of the eastern bore.Barrow, Keith. "Tracklaying begins in Ceneri Base Tunnel." railjournal.com, 1 August 2017. On 30 May 2018, the final railroad tie was laid, meaning that trains would be able to travel the entire length of the tunnel.
The tunnel was officially opened on 4 September 2020. Final testing concluded with a rescue test in October 2020, and routine operations began in December 2020. The construction has cost CHF 2.5bn.
+ Construction monthly progress Year Month Total excavated km mi %percentage of 2010 1 January 18.9 1 February 19.0 1 March 19.1 1 April 19.4 1 May 19.8 1 June 20.4 1 July 21.0 1 August 22.2 1 September 22.9 1 October 23.8 1 November 25.0 1 December 26.3 2011 1 January 27.2 1 February 28.6 1 March 29.9 1 April 31.0 1 May 31.8 1 June 33.0 1 July 34.2 1 August 35.1 1 September 35.8 1 October 37.2 1 November 39.1 1 December 40.9 2012 1 January 42.4 1 February 43.7 1 March 45.2 1 April 46.9 1 May 48.3 1 June 50.3 1 July 51.8 1 August 53.1 1 September 53.7 1 October 54.8 1 November 56.0 1 December 57.3 2013 1 January 57.9 1 February 59.0 1 March 60.5 1 April 61.8 1 May 63.2 1 June 64.5 1 July 65.6 1 August 66.5 1 September 67.4 1 October 68.6 1 November 70.0 1 December 71.7 2014 1 January 71.7 1 February 73.9 1 March 74.8 1 April 76.0 1 May 76.9 1 June 78.6 1 July 80.2 1 August 81.9 1 September 82.5 1 October 84.1 1 November 85.4 1 December 86.4 2015 1 January 87.3 1 February 88.8 1 March 90.2 1 April 91.3 1 May 92.5 1 June 93.8 1 July 94.7 1 August 95.7 1 September 96.2 1 October 97.2 1 November 97.9 1 December 99.1 2016 1 January 99.7 1 February 100Note:
The monthly progress update graphic was available online.
See also NRLA Gotthard Base Tunnel Lötschberg Base Tunnel Zimmerberg Base Tunnel
References
External links
AlpTransit Gotthard AG - Official company site AlpTransit Gotthard AG - Status of construction: Ceneri AlpTransit Portal of the Swiss Federal Archives