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What were the main challenges when the decision was made to build the Lötschberg tunnel?
Kees van Hoek: The Lötschberg base tunnel is one of the biggest single infrastructure projects ever undertaken in Europe. The tunnel is more than 34km in length and as well as being a huge challenge in civil engineering terms, we worked to a number of tough targets. These included a planned eight-year construction timetable, a requirement to stay within the €2.7 billion budget and the decision to build the first ETCS (European Train Control System) Level 2 route, without lineside signals, to support both passenger and freight operation.

What's the basic concept?
The Lötschberg base tunnel is the safest, most modern and technically advanced railway tunnels in the world. It is designed as a dual-tube, single-track tunnel for the maximum possible operational safety. For cost reasons, the parallel tube has not been entirely completed and has been left in its carcass state. Both tubes are linked by a transverse tunnel every 333 metres. This enables one tunnel to become the rescue tunnel for the other. In addition, all of the tunnel systems are duplicated, meaning that, should a technical malfunction occur, operation can continue via the ‘twin' system.

What benefits does the tunnel bring?
One of the main aims is to shift traffic from road to rail in order to protect the Alpine environment. In tandem with this, the tunnel provides a great number of strategic benefits, both for Switzerland and for Europe.

For goods traffic, the new base line confers a decisive capacity increase to the Lötschberg-Simplon axis and consequently also creates the conditions for shifting as much trans-Alpine goods traffic as possible from road to rail, in line with the wishes of the Swiss electorate.

The new trans-Alpine link through the Lötschberg tunnel creates a shorter, more reliable and higher capacity north-south connection for passengers and freight. Trains pass through the new tunnel at speeds of up to 250kmh. It will make the different areas of both Switzerland and Europe more readily accessible. Journeys from the Swiss plateau to the canton of Valais, from Frankfurt to Milan and from the North Sea to the Mediterranean will shorten by up to one hour.

What is the capacity of the tunnel?
For the Lötschberg base tunnel (LBT), the record for a single day is 108 trains. Our capacity aim is 120. On the Lötschberg axis, the single-day record so far is 102,323 gross tonnes.

In order to optimise the use of the tunnel, freight traffic is ‘bundled' into groups of trains travelling in the same direction. In tandem with this, we operate the new base tunnel and the original mountain line as an integrated system to maximise capacity.

Why is European Train Control System (ETCS) signalling technology crucial to the management of tunnel traffic?
The new ETCS Level 2 train protection system is used in the base tunnel in order to achieve the high speeds - up to 250kmh - and short headways necessary to implement the intended timetable. In this standardised European system, travel commands are no longer given by external visual signals, but are transmitted directly to a display in the driver's cab using the GSM-R digital radio network. The base tunnel is totally reliant on ETCS Level 2: there is neither a fallback system, nor are there optical signals.

How are other tunnel assets controlled?
Operators control the tunnel's systems remotely via a tunnel control system from the operations control centre in Spiez. The systems include:

· Ventilation systems for fresh and exhaust air
· An air-conditioning system in the containers and cabinets
· Sluices, doors, sliding doors, railway tunnel doors
· Water supply and removal (fire, cooling, service and wastewater)
· Fire alarm system (fire, flood and gas detection, fire extinguishing systems)
· Communication systems (landline telephones, mobile radio, radio, loudspeaker systems)
· Lighting, light signalling system in the service tunnel
· Video system and access control system
· Power supply (excluding rail power) and emergency power groups
· Data lines

How is maintenance carried out in the tunnel?
Track maintenance in the Lötschberg base tunnel is carried out by the regular BLS maintenance services - trackway, train protection systems, rail power, telecommunication, civil engineering. The objective is to be able to maintain the systems with minimal effort and without impacting on operational availability to any great extent. To this end, the entire tunnel is closed every Sunday night, and a single track of the southern section is also closed on Monday night. Additional maintenance intervals are used during a four-week period in the summer.

Such restricted work periods, and the remoteness of work sites, place high demands on employees and equipment. BLS has therefore purchased a number of new vehicles for special use in tunnel maintenance. These vehicles will be stationed at the new Frutigen maintenance and intervention centre. The vehicles include three diesel locomotives, two self-propelling intervention vehicles and 12 self-propelling maintenance vehicles with modular superstructures and six transport containers (team containers and mobile workshops).

How do you deal with emergencies?
Safety is at the heart of everything we do. Outside the tunnel, detection devices are installed which will, in most cases, prevent a damaged train from entering the tunnel. If an unforeseen incident takes place on the Lötschberg base line (e.g. in the event of a fire), the affected train will, if possible, try to leave the tunnel. If this is not possible, it attempts to reach the emergency stopping point or the intervention points outside the tunnel. If the train stops in the tunnel, passengers and the train crew can escape through the transverse tunnels every 333 metres to one of the protected areas along the parallel tubes and await assistance there. In the southern part of the tunnel (double track) an evacuation can then take place via the parallel railway, on the northern side (single track) by bus.

The incident services must reach the damage site within 45 minutes in order to start rescue and damage abatement operations. BLS's new fire-fighting and rescue train forms the centrepiece of intervention operations. This special train comprises a fire-fighting car, a water car and rescue equipment cars to evacuate the affected passengers and crew. It is stationed at BLS's newly-built maintenance and intervention centre at Frutigen. An additional intervention centre, which is operated by the SBB, is located at Brig on the southern side of the base tunnel.

The intervention personnel consist of the railway fire brigades of the BLS and SBB, the two rail companies, which are supported by local fire brigades. In total, 150 fire-fighting crew and 20 members of the police, ambulance and other essential services of the canton have been trained for intervention in the Lötschberg base tunnel. This number is supplemented by 90 bus drivers from PostAuto AG in Upper Valais who can also be deployed in the event of a passenger evacuation.