The Channel Tunnel

Unique in the world, the cross-Channel Fixed Link is the only way to cross the stretch of water between Great Britain and continental Europe in total safety, 365 days a year, 24 hours a day.

The Channel Tunnel is the longest undersea tunnel in the world. The section under the sea is 38km long. The three tunnels, each 50km long, were bored at an average 40m below the sea bed, and link Folkestone in Kent to Coquelles in Pas-de-Calais.

In addition to being the world’s longest undersea railway tunnel, the Eurotunnel network is also setting records in terms of its operations. More than 270 trains run each day, representing one train every 3 minutes at peak times. The Truck Shuttles carry up to 32 heavy goods vehicles, each weighing up to 44 tonnes. These 800-metre long trains run at 140 kph. The Passenger Shuttles travel at the same speed and transport up to 120 cars and 12 coaches. The Eurostar trains travel at 160 kph below the sea. Some of the Freight Shuttles weigh in at 2,500 tonnes.

All this makes extreme demands on the equipment. For instance, in 16 years of operations, all the Tunnel’s rails (excluding points) have already been changed twice. Their quality is not at issue: they simply wear out much quicker than in conventional networks due to the unique load they carry – the highest in the world – with around 120 million tonnes each year.

Tunnel history goes back to  1802, when French mining engineer Albert Mathieu-Favier put forward the first ever design for a cross-Channel fixed link based on the principle of a bored two-level tunnel: the top one, paved and lit by oil lamps, to be used by horse-drawn stagecoaches; the bottom one would be used for groundwater flows. In 1803  the Englishman Henry Mottray unveiled another project for a cross-Channel fixed link: a submerged tunnel made of prefabricated iron sections.

From 1830, the advent of steam trains and the construction of the rail network in Britain led to the first proposals for a rail tunnel. French mining engineer, Aimé Thomé de Gamond, spent 30 years working on seven different designs.  During the state visit to France in Versailles, on 25th of August, 1855, Queen Victoria and Napoléon III approve the proposed undersea tunnel designed by Thomé de Gamond, which was later on presented in the Exposition Universelle of Paris in 1867.

The first attempt of a tunnel excavation began in 1880 when the « Beaumont & English » tunnel boring machine began digging undersea on both sides of the Channel.ButWorldWarschangedallplans. Harold Macmillan, British Defence Minister, announced that he no longer opposed a fixed link on military ground only in 1955. Louis Armand formed the Channel Tunnel Study Group (GETM) on 26th of July, 1957. The Group presented to the governments a proposal of railway tunnel, bored of submerged, comprising a twin rail tunnel with a service tunnel in 1960.

The project of the construction and the operations of a railway tunnel under the Channel were finally launched on 17th of 1973 at Chequers by Edward Heath, British Prime Minister, and Georges Pompidou, French President, when a Franco-British Channel Tunnel Treaty was signed.

1975 -  Harold Wilson, British Minister, announces that the project is stopped and withdrawn for financial reasons and in particular due to the oil crisis.

The British and French Governments reached an agreement on a consultation process with private promoters for the construction and operation of a cross-Channel fixed link, without public funding in 1984.

In 1986 Margaret Thatcher and François Mitterrand announced in Lille that the Eurotunnel bid presented by a Franco-British Consortium « France-Manche-Channel Tunnel Group » had been selected.The Concession Agreement for the construction, the financing and operation of the Channel Tunnel was awarded to the Franco-British Consortium « France- Manche SA / The Channel Tunnel Group Ltd» for a period of 55 years.

19th of May 1986 - Launch of the Eurotunnel logo, representing the holding company comprising the Concessionaires « France-Manche » and « The Channel Tunnel Group Limited ».

29th of July, 1987  -  In Paris, Margaret Thatcher and François Mitterrand ratified the Treaty of Canterbury, paving the way for the Channel Tunnel to become a reality.Boring of the service tunnel started on the UK side on 15th of 1987.

28th of February 1988 -  Start of the service tunnel boring on the French side.

1st December at 12:12 CET British and French teams achieved the first historic breakthrough under the Channel, in the service tunnel at 22.3 km from the UK and 15.6 from France.  The Northrailtunneland the Southrailtunnel were completed on  22th of May  1991 and 28th of June 1991 respectively. Equipment installation, completion work and testing on the whole Concession (tunnels, terminals, etc) lasted until April 1994.

6th of May, 1994 - Official opening by Queen Elizabeth II and French President François Mitterrand.

Eurotunnel shuttles, Eurostar and national freight trains run in the two single track and single direction tunnels. These are connected to a central service tunnel by cross-passages situated every 375m. The service tunnel allows access to maintenance and emergency rescue teams and serves as a safe haven if passengers need to be evacuated in an incident. The service tunnel is a road tunnel used by electric and diesel-powered vehicles. Air pressure is higher in the service tunnel to prevent the ingress of smoke in case of a fire in one of the rail tunnels.

The two rail tunnels are 7.6m in diameter and 30m apart. Each rail tunnel has a single track, overhead line equipment (catenary) and two walkways (one for maintenance purposes and the other for use in the event of an emergency evacuation and on the side nearest the service tunnel). The walkways are also designed to maintain a shuttle upright and in a straight line of travel in the unlikely event of a derailment.

The service tunnel is 4.8m in diameter and lies between the two rail tunnels 15m away from each of them. In normal operations shuttles use the south tunnel in the France – UK direction, and the north tunnel when travelling from the UK to France.

Two undersea crossovers bring flexibility of operation as trains can pass from one tunnel to the other during night maintenance periods to isolate a section of tunnel.

The fixed lighting installations can be switched on from the control centre or manually from within the tunnels. Various fire-protection and detection systems are installed at points along the length of the tunnels.

Although the transport system is automated, controllers are in attendance 24 hours a day, ready to take manual control in the event of technical failure.

Since commercial services started progressively from May 1994, more than 304 million passengers have travelled through the Channel Tunnel, i.e. the equivalent to almost 5 times the population of the United Kingdom.

This project has political and economic influence for Europe. Also it changed the comfort level for travelers.  The journey from Paris to London takes about 2 hours now.   

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