CHANNEL TUNNEL

 

CHANNEL TUNNEL :

                       

Ø  The Channel Tunnel (often called the 'Chunnel' for short) is an undersea tunnel linking southern England and northern France. It is operated by the company Getlink, who also run a railway shuttle (Le Shuttle) between Folkestone and Calais, carrying passengers in cars, vans and other vehicles.

Ø  Eurostar is a totally separate company and is Getlink’s biggest customer, running high-speed passenger services through the Channel Tunnel between London and a number of other European cities on the continent, including Paris, Brussels, Lille, Lyon, Avignon and Marseille.

Ø  The Chunnel is actually comprised of three tunnels: two rail tunnels, used for freight and passenger trains, and a service tunnel

                            

INITIATION OF PROJECT :

 

Ø  Channel Tunnel, a rail proposal based on the 1975 scheme presented by Channel Tunnel Group/France–Manche (CTG/F–M).

Ø  Eurobridge, a 35-kilometre (22 mi) suspension bridge with a series of 5 km (3.1 mi) spans with a roadway in an enclosed tube.

Ø  Euroroute, a 21-kilometre (13 mi) tunnel between artificial islands approached by bridges.

Ø  Channel Expressway, a set of large-diameter road tunnels with mid-Channel ventilation towers.

Ø  The cross-Channel ferry industry protested under the name "Flexilink". In 1975 there was no campaign protesting a fixed link, with one of the largest ferry operators (Sealink) being state-owned. Flexilink continued rousing opposition throughout 1986 and 1987.  Public opinion strongly favoured a drive-through tunnel, but concerns about ventilation, accident management and driver mesmerisation led to the only shortlisted rail submission, CTG/F-M, being awarded the project in January 1986. Reasons given for the selection included that it caused least disruption to shipping in the Channel and least environmental disruption, was the best protected against terrorism, and was the most likely to attract sufficient private finance.

                                               

                    Cost :

 

Ø  The tunnel is a build-own-operate-transfer (BOOT) project with a concession.TML would design and build the tunnel, but financing was through a separate legal entity, Eurotunnel. Eurotunnel absorbed CTG/F-M and signed a construction contract with TML, but the British and French governments controlled final engineering and safety decisions, now in the hands of the Channel Tunnel Safety Authority. A Railway Usage Agreement was signed between Eurotunnel, British Rail and SNCF guaranteeing future revenue in exchange for the railways obtaining half of the tunnel's capacity.

Ø  Private funding for such a complex infrastructure project was of unprecedented scale. An initial equity of £45 million was raised by CTG/F-M, increased by £206 million private institutional placement, £770 million was raised in a public share offer that included press and television advertisements, a syndicated bank loan and letter of credit arranged £5 billion. Privately financed, the total investment costs at 1985 prices were £2.6 billion. At the 1994 completion actual costs were, in 1985 prices, £4.65 billion: an 80% cost overrun. The cost overrun was partly due to enhanced safety, security, and environmental demands. Financing costs were 140% higher than forecast.

 

                    Construction :

 

Ø  Working from both the English and French sides of the Channel, eleven tunnel boring machines cut through chalk marl to construct two rail tunnels and a service tunnel. The vehicle shuttle terminals are at part of Folkestone and Coquelles, and are connected to the English  and French motorways respectively. Tunnelling commenced in 1988, and the tunnel began operating in 1994. The tunnel was officially opened, one year later than originally planned, by Queen Elizabeth II and the French president, François Mitterrand, in a ceremony held in Calais on 6 May 1994.

Ø  A full public service did not start for several months. The first freight train, however, ran on 1 June 1994 and carried Rover and Mini cars being exported to Italy. In 1994, the American Society of Civil Engineers elected the tunnel as one of the seven modern Wonders of the World.

Ø  In 1995, the American magazine Popular Mechanics published the results.

                           

                 OPENING :

 

Ø  Opening was phased for various services offered as the Channel Tunnel Safety Authority, the IGC, gave permission for various services to begin at several dates over the period 1994/1995 but start up dates were a few days later.

Ø  Surveying undertaken in the 20 years before construction confirmed earlier speculations that a tunnel could be bored through a chalk marl stratum. The chalk marl is conducive to tunnelling, with impermeability, ease of excavation and strength. The chalk marl runs along the entire length of the English side of the tunnel, but on the French side a length of 5 kilometres (3 mi) has variable and difficult geology. The tunnel consists of three bores: two 7.6-metre (25 ft) diameter rail tunnels, 30 metres (98 ft) apart, 50 kilometres (31 mi) in length with a 4.8-metre (16 ft) diameter service tunnel in between. The three bores are connected by cross-passages and piston relief ducts. The service tunnel was used as a pilot tunnel, boring ahead of the main tunnels to determine the conditions. English access was provided at Shakespeare Cliff, French access from a shaft at Sangatte. The French side used five tunnel boring machines (TBMs), the English side six. The service tunnel uses Service Tunnel Transport System (STTS) and Light Service Tunnel Vehicles (LADOGS). Fire safety was a critical design issue.

Ø  Environmental impact assessment did not identify any major risks for the project, and further studies into safety, noise, and air pollution were overall positive. However, environmental objections were raised over a high-speed link to London.

                               

                 SURVEYING :

 

Ø  The surveying catered for immersed tube and bridge designs as well as a bored tunnel, and thus a wide area was investigated. At this time, marine geophysics surveying for engineering projects was in its infancy, with poor positioning and resolution from seismic profiling. The surveys concentrated on a northerly route that left the English coast atDoverharbour;usingmoreboreholes, an area of deeply weathered rock with high permeability was located just south of Dover harbour.

 

Ø  Given the previous survey results and access constraints, a more southerly route was investigated in the 1972–73 survey, and the route was confirmed to be feasible. Information for the tunnelling project also came from work before the 1975 cancellation. On the French side at Sangatte, a deep shaft with adits was made. On the English side at Shakespeare Cliff, the government allowed 250 metres (820 ft) of 4.5-metre (15 ft) diameter tunnel to be driven. The actual tunnel alignment, method of excavation and support were essentially the same as the 1975 attempt. In the 1986–87 survey, previous findings were reinforced, and the characteristics of the gault clay and the tunnelling medium (chalk marl that made up 85% of the route) were investigated. Geophysical techniques from the oil industry were employed

                                           

 

                  Tunnelling :

 

Ø  The eleven tunnel boring machines were designed and manufactured through a joint venture between the Robbins Company of Kent, Washington, United States; Markham & Co. of Chesterfield, England; and Kawasaki Heavy Industries of Japan.[83] The TBMs for the service tunnels and main tunnels on the UK side were designed and manufactured by James Howden & Company Ltd, Scotland.

                                                

 

                 Tunnel boring machines :

 

Ø  The eleven tunnel boring machines were designed and manufactured through a joint venture between the Robbins Company of Kent, Washington, United States; Markham & Co. of Chesterfield, England; and Kawasaki Heavy Industries of Japan.The TBMs for the service tunnels and main tunnels on the UK side were designed and manufactured by James Howden & Company Ltd, Scotland.

                                               

 

 

                Principal items of the fixed equipment :

 

Ø  Mechanical equipment in the tunnels

Ø  550km of pipes

Ø  2 ventilation systems

Ø  1 cooling system with the two cooling plants at Shakespeare Cliff and Sangatte

Ø  1 drainage system with 6 pumping stations

Ø  1 fire main, with 2 huge reservoirs at each end and their pumping stations

Ø  600 cross-passage doors and the giant cross-over doors

Ø  Track and catenaries

Ø  200km of track, including 100km in the tunnels and 176 points, including 4 cross-overs

Ø  950km of catenary cables.

                               

            Electricity supply :

Ø  2 substations connected to the British and French grids to supply the 25,000volts for the traction and the 21,000volts (three-phase) for other fixed equipment

Ø  175 secondary substations (high, medium and low voltage supply), 350km of supporting structures and more than 1,300km of cables in the tunnels

Ø  20,000 lighting fixtures.

 

           Regional impact :

Ø  A 1996 report from the European Commission predicted that Kent and Nord-Pas de Calais had to face increased traffic volumes due to general growth of cross-Channel traffic and traffic attracted by the tunnel. In Kent, a high-speed rail line to London would transfer traffic from road to rail. Kent's regional development would benefit from the tunnel, but being so close to London restricts the benefits. Gains are in the traditional industries and are largely dependent on the development of Ashford International railway station, without which Kent would be totally dependent on London's expansion. Nord-Pas-de-Calais enjoys a strong internal symbolic effect of the Tunnel which results in significant gains in manufacturing.

 

Ø  Since the opening of the tunnel, small positive impacts on the wider economy have been felt, but it is difficult to identify major economic successes directly attributed to the tunnel.The Eurotunnel does operate profitably, offering an alternative transportation mode unaffected by poor weather. High costs of construction did delay profitability, however, and companies involved in the tunnel's construction and operation early in operation relied on government aid to deal with debts amounted.