Channel Tunnel
The Channel Tunnel, (or Chunnel, or le tunnel sous la Manche) is a rail tunnel beneath the English Channel at the Straits of Dover, connecting Cheriton in Kent, England and Sangatte in northern France. A long-standing project that saw several false starts, it was finally completed in 1994.
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2 The current tunnel 3 External links 4 See Also |
A link between Britain and France had been proposed on many occasions, but it was not until the 19th century that engineers came to believe that the necessary technical ability was available. Various French and British engineers put forward proposals and works on a tunnel were briefly undertaken in 1880 (but soon abandoned due to flooding). The British government was, however, firmly opposed to a link, fearing that it could serve the French as an invasion route. It was not until after World War II that the concept began to receive serious attention.
In 1984 the idea was relaunched with a Anglo-French government request for proposals to build a privately funded link. Of the four submissions received the one most closely resembling the 1973 plan was chosen and announced on January 20, 1986. The Fixed Link Treaty was signed by the two governments in Canterbury, Kent on February 12, 1986 and ratified in 1987.
The planned route of the tunnel took it from Calais to Folkestone (a route rather longer than the shortest possible crossing) and the tunnel was to follow a single chalk stratum (which meant the tunnel was deeper than the previous attempt). For much of its route, the tunnel is nearly 40m under the seafloor, with the southern section being deeper than the northern.
Digging the tunnel took 15,000 workers over seven years , with tunnelling operations conducted simultaneously from both ends. The prime contractor for the construction was anglo-french Transmanche-Link, a consortium of construction companies. Engineers used large Tunnel Boring Machines (TBMs), mobile excavation factories that combined drilling, material removal, and the process of shoring up the soft and permeable tunnel walls with a concrete liner. After the British and French TBMs had met near the middle, the French TBM was dismantled while the British one was diverted into the rock and abandoned. Three tunnels were dug: two primary ones, which carry trains north and south, and a smaller access tunnel. This access tunnel (which is served by narrow wheeled vehicles) is interconnected, by means of transverse passages, to the main tunnels at regular intervals. It allows maintainance workers access to the tunnel complex, provides a safe route for escape during emergencies, and dissipates the aerodynamic shockwave that would otherwise accumulate in front of a train travelling through a main tunnel at full speed.
When the two tunnels met 40 meters beneath the English Channel seabed on 1 December 1990 (in what was to become one of the "crossover halls" that allow diversion of trains from one main tunnel to the other), it became possible to walk on dry land from mainland Britain to Europe for the first time since the Weichsel glacial period, over 13,000 years ago. The British and French efforts, which had been guided by laser surveying methods, met with less than 2 cm of error.
The tunnel was officially opened by the Queen and French President Francois Mitterrand during a ceremony on May 6, 1994.
It is 50 km long, out of which 39 km are undersea. The average depth is 40 m underneath the seabed. It opened for travel later in 1994 and its rail service carries vehicles as well as passengers. Nearly 7 million passengers take the 35 minute journey travel through the tunnel every year.
The American Society of Civil Engineers have declared the tunnel to be one of the modern Seven Wonders of the World.
The tunnel is operated by Eurotunnel. Four types of train services operate:
The tunnel has become a popular means by which asylum seekers, hoping their chances of receiving asylum are better in the UK than in France, illegally enter the UK. A few attempt to walk through the tunnel or to cling to the trains themselves, but most try to hide in freight containers or trucks using the tunnel. In 2002, British immigration authorities added sophisticated listening and imaging equipment to their post in Kent, hoping to hear the heartbeats or sense the breathing of such stowaways. In early 2003 the British government persuaded French authorities to close the controversial center for asylum seekers at Sangatte, which they felt encouraged such clandestine travel.Previous attempts
The current tunnel
Planning
In 1957 the Channel Tunnel Study Group was formed. It reported in 1960 and recommended a railway tunnel of two main tunnels and a smaller service tunnel. The project was launched in 1973 before the folding due to financial problems in 1975.Construction
Completion
Statistics
Operation
Although Eurostar trains travel at high speeds in France (where the tracks are modern and custom-made for high speed travel), their speed in Kent is limited by the condition of the normal tracks over which they must run. The British government has instituted The Channel Tunnel Rail Link project, to a high-speed line from London to the tunnel. As of late 2003, around half the distance is improved (the section from mid-Kent to Cheriton).Asylum seekers
