Improving routes and times

The Haut Bugey line project is one of several Franco-Suisse projects. Its aim is to improve train links between France and Switzerland, as per the agreement signed in 1999 by French and Swiss governments. Although the project is entirely located in France, the Swiss government provides close to one third of the financing for the €340 million project, in line with the expected benefits for Switzerland.

Before the opening of the first TGV line, Paris-Genève passengers travelled by way of Lausanne. This journey usually involved a change of train, and thus offered a rather poor service and an uncompetitive travel time of approximately 6 hours.

With the opening in 1981 of the Paris to Lyon TGV line (LN1), the journey time between Paris and Genève fell to 3 hours and 30 minutes. The route was changed, and trains began running at high-speed between Paris and Macon, then leaving the high-speed line at Macon and carrying on through Bourg-en-Bresse, Amberieu, Culoz, Bellegarde-sur-Valserine and on to Genève. This helped greatly in building up an efficient train service between Paris and Genève. Travel time was further reduced to 3 hours and 22 minutes when the maximum operational speed on the LN1 High-Speed line was increased from 270km/h to 300km/h in 2004. Such travel time however remained just above the 3 hour threshold where train takes advantage over planes for that type of journey. Journey times will not be expected to increase in the near future, neither on the high-speed line nor on the classical line between Macon and Bellegarde-sur-Valserine, due to the curvature and gradient of the line. Besides, the section between Macon and Amberieu also accommodates freight traffic, often conflicting with passenger traffic.

To gain a journey time below the 3 hour threshold, various options, involving boring long tunnels through the Jura Mountains, were studied but later abandoned because of high costs. One option, however, appeared to be cost-effective while meeting the target. This option was to modernize an existing line linking Bourg-en-Bresse and Bellegarde-sur-Valserine by way of Nantua. This route is 47km shorter than the current one (65km long via Nantua against 112km long via Amberieu) and it was expected that it will cut journey times by 20 minutes. Another advantage is to free, for freight traffic, train paths currently used by TGVs on the Bourg-en-Bresse – Amberieu section.

The Bourg-en-Bresse – Bellegarde-sur-Valserine line

The so-called ‘carpate’s line’, linking Bourg-en-Bresse and Bellegarde-sur-Valserine via Nantua, was in operation from the late 19th Century until 2005.

Operation of the section between Bourg-en-Bresse and the junction onto Oyonax (hereafter called first section) started in 1877 and was suspended in August 2005 until modernization works are completed.

Operation of the section between junction onto Oyonax and Bellegarde-sur-Valserine (hereafter called second section) started in 1882 and was stopped in 1990.

The 65km long railway runs through the mountainous region of the Haut Bugey, reaching an altitude of 600m by the Lake of Sylans. Sylans is known as a very cold area where, until not so long ago, ice was extracted from the lake and stored in deep wells to be sent to Paris or Marseilles almost all year round. From Nantua to Bellegarde-sur-Valserine, snow can be expected for at least three months a year, sometimes as late as April.

The line curves around peaks, travelling up and down steep gradients (often 2%). Many curves have radiuses of 300m or less. After modernisation, operation will start again on the whole of the line. The first section will accommodate both TGVs and regional traffic originating either from Lyon or Bourg-en-Bresse and carrying on onto Oyonax and Saint Claude while only TGVs will travel the second section.

The project

Preliminary studies started in the late 90s, at the time RFF was created to take over the French railways infrastructure from SNCF. Concertation procedures, both within the French administration and with the public were completed in early 2003 for the former and by the end of 2003 for the latter. The Swiss government confirmed its financing (€110 million) in September 2003. The project was approved and it was decided to go on with the next phase. The consulting engineer was chosen through a competitive bid process to perform detailed design and prepare tender documents for the works. That phase started in 2004 and was completed in early 2006 with regards to the detailed design and is still going on for railway equipment tenders.

Given the area that the project is going through, environment is a crucial issue. Although noise levels will be lower than the ones generated by the rolling stock operated up until 2005 on the jointed existing track, an approximate length of 4000m of noise protection walls will be erected.

Running through highly renowned sites such as Nantua and the Sylans lakes at the foot of cliffs, special measures have to be taken to ensure preservation while making sure safety is maintained and reinforced. Discreet safety nets will be installed in the slopes facing the lake so that in a few years time they will be hardly noticeable.

Although diesel trains are prohibited in these areas, the track will be made water-tight when passing close to water resources used for human consumption. Drastic safety measures are taken while the works are performed, such as closing down sensitive water resources and providing alternative ones for the duration of the works.

One of the main characteristics of the project is to use the existing platform. Besides the new viaduct in Bellegarde-sur-Valserine there is only one location where the project gets away from the existing platform. Leaving Bourg-en-Bresse the track was supposed to follow a large curve which would allow a maximum speed of 140km/h for a few kilometres. But during the design phase, a European-protected species was discovered in the area and, to ensure its preservation, the project had to be changed and the speed had to be brought down from 140 to 120km/h.

In early 2005, the project was declared as ‘urgent and in the public interest’. This allows expropriation should the need arise. Until now, all properties have been bought after negotiation based on market price. Tender procedures for the civil works were carried out in early 2005 and bids were received in October of the same year. Bid analysis and negotiations took place at the end of 2005 – early 2006.

Financing for the construction phase was eventually totally secured by mid-2006, and authorization to begin with the works was received in September 2006. Civil works contractors were notified in November 2006 and the final detailed design for civil works began while all safety measures related to the works, such as road traffic and water resources protection, were implemented.

Railway equipment tenders for track, catenary systems, telecommunications and GSM-R will be released during 2007.
The civil works are mainly modifications and adjustments to the electrification gauge of 80 bridges and 11 tunnels, totalling 7.4km in length. Some bridges will be totally rebuilt.

Tunnels will be made water tight, carefully avoiding disturbance to existing water paths that feed surroundings villages. They will also be made safer by installing lighting, water tanks and by keeping rail-road fire engines ready to intervene at specific locations along the line and through other safety measures.

Because of all the safety risks involved, each and every level crossing has been carefully studied and actions will be taken to cancel as many of them as possible. Altogether, 15 level crossings will be suppressed.Two level crossings will be replaced by special undertrack paths for cattle, while two others, classified as potentially dangerous, will be replaced by bridges.

Six passing loops shall be lengthened and renewed and a new TGV station shall be built in Nurieux to ease transportation to and from the French plastic valley of Oyonax.

Arriving in Bellegarde-sur-Valserine, a new bridge will allow trains to proceed on to Genève without reversing. Because of the rather steep slope (a gradient of about 2%), a shunting track with a buffer stop will take on any drifting train.

A multimodal platform with three new car parks will allow easy transfer between TGVs, regional trains and buses in Bellegarde-sur-Valserine. The ‘flying saucer’ shaped new station, besides being most functional, is also environmentally friendly, requiring very little energy to cool or heat.

Curves will be eased to allow for a slight increase in speed and a smoother ride. Maximum speeds will be 120km/h leaving Bourg-en-Bresse going to Ceyzeriat and in the Mornay tunnel until the train reaches Brion. For the remaining part of the line, the speed will be 80 to 100km/h depending on the curves and gradient. 65km of track (LWR) and ballast will be totally renewed. The line will be electrified at 2×25 KV 50 Hz with the construction of a 2×25 KV substation at Cise-Bolozon. A rigid catenary system shall be implemented in the longer tunnels and the line will be re-signalled with automatic block colour light signal and KVB beacons. Solid state pc-based interlockings will be installed at each passing loop and the line will be remote-controlled from Bellegarde-sur-Valserine where the same SSI equipment, with a human-machine interface, will be installed in a brand new cabin. A GSM-R telecommunication system will also be implemented to reinforce safety. Works completion date is set for the second half of 2009.

About the author

Jean-Damien Bierre is an ENSEEIHT graduate (electrotechnical engineer). He led important projects abroad for French firms (subways of Hong Kong and Athens) and was a manager of the Danish branch of Spie Enertrans from 1997-2004. He joined Réseau Ferré de France (RFF) in 2004 as Project Manager of the Haut Bugey mission.