Thames Tunnel
Encyclopedia
The Thames Tunnel is an underwater tunnel
Tunnel
A tunnel is an underground passageway, completely enclosed except for openings for egress, commonly at each end.A tunnel may be for foot or vehicular road traffic, for rail traffic, or for a canal. Some tunnels are aqueducts to supply water for consumption or for hydroelectric stations or are sewers...

, built beneath the River Thames
River Thames
The River Thames flows through southern England. It is the longest river entirely in England and the second longest in the United Kingdom. While it is best known because its lower reaches flow through central London, the river flows alongside several other towns and cities, including Oxford,...

 in London
London
London is the capital city of :England and the :United Kingdom, the largest metropolitan area in the United Kingdom, and the largest urban zone in the European Union by most measures. Located on the River Thames, London has been a major settlement for two millennia, its history going back to its...

, United Kingdom, connecting Rotherhithe
Rotherhithe
Rotherhithe is a residential district in inner southeast London, England and part of the London Borough of Southwark. It is located on a peninsula on the south bank of the Thames, facing Wapping and the Isle of Dogs on the north bank, and is a part of the Docklands area...

 and Wapping
Wapping
Wapping is a place in the London Borough of Tower Hamlets which forms part of the Docklands to the east of the City of London. It is situated between the north bank of the River Thames and the ancient thoroughfare simply called The Highway...

. It measures 35 feet (11 m) wide by 20 feet (6 m) high and is 1,300 feet (396 m) long, running at a depth of 75 feet (23 m) below the river's surface (measured at high tide). It was the first tunnel known successfully to have been constructed underneath a navigable river,
and was built between 1825 and 1843 using Thomas Cochrane
Thomas Cochrane, 10th Earl of Dundonald
Admiral Thomas Cochrane, 10th Earl of Dundonald, 1st Marquess of Maranhão, GCB, ODM , styled Lord Cochrane between 1778 and 1831, was a senior British naval flag officer and radical politician....

 and Marc Isambard Brunel
Marc Isambard Brunel
Sir Marc Isambard Brunel, FRS FRSE was a French-born engineer who settled in England. He preferred the name Isambard, but is generally known to history as Marc to avoid confusion with his more famous son Isambard Kingdom Brunel...

's newly invented tunnelling shield
Tunnelling shield
A tunnelling shield is a protective structure used in the excavation of tunnels through soil that is too soft or fluid to remain stable during the time it takes to line the tunnel with a support structure of concrete, cast iron or steel...

 technology, by him and his son Isambard Kingdom Brunel
Isambard Kingdom Brunel
Isambard Kingdom Brunel, FRS , was a British civil engineer who built bridges and dockyards including the construction of the first major British railway, the Great Western Railway; a series of steamships, including the first propeller-driven transatlantic steamship; and numerous important bridges...

.

The tunnel was originally designed for, but never used by, horse-drawn carriages and now forms part of the London Overground
London Overground
London Overground is a suburban rail network in London and Hertfordshire. It has been operated by London Overground Rail Operations since 2007 as part of the National Rail network, under the franchise control and branding of Transport for London...

 railway network.

Construction

At the start of the 19th century, there was a pressing need for a new land connection between the north and south banks of the Thames to link the expanding docks on both sides of the river. The engineer Ralph Dodd
Ralph Dodd
Ralph Dodd was a late 18th century engineer primarily known, by his detractors, for his attempt, and ultimate failure to produce a tunnel underneath the Thames.-Marine painter:...

 tried, but failed to build a tunnel between Gravesend
Gravesend, Kent
Gravesend is a town in northwest Kent, England, on the south bank of the Thames, opposite Tilbury in Essex. It is the administrative town of the Borough of Gravesham and, because of its geographical position, has always had an important role to play in the history and communications of this part of...

 and Tilbury
Tilbury
Tilbury is a town in the borough of Thurrock, Essex, England. As a settlement it is of relatively recent existence, although it has important historical connections, being the location of a 16th century fort and an ancient cross-river ferry...

 in 1799.

In 1805–1809 a group of Cornish
Cornish people
The Cornish are a people associated with Cornwall, a county and Duchy in the south-west of the United Kingdom that is seen in some respects as distinct from England, having more in common with the other Celtic parts of the United Kingdom such as Wales, as well as with other Celtic nations in Europe...

 miners, including Richard Trevithick
Richard Trevithick
Richard Trevithick was a British inventor and mining engineer from Cornwall. His most significant success was the high pressure steam engine and he also built the first full-scale working railway steam locomotive...

, attempted to dig a tunnel further upriver between Rotherhithe and Wapping/Limehouse but failed because of the difficult conditions of the ground. The Cornish miners were used to hard rock and did not modify their methods for soft clay and quicksand. The "Thames Archway" project was abandoned after the initial pilot tunnel (a 'driftway') flooded twice when 1,000 feet (305 m) of a total of 1,200 feet (366 m) had been dug. It only measured 2–3 feet by 5 feet (61–91 cm by 1.5 m), and was intended as the drain for a larger tunnel for passenger use.

The failure of the Thames Archway project led engineers to conclude that "an underground tunnel is impracticable". However, the Anglo-French engineer Marc Brunel refused to accept this conclusion. In 1814 he proposed to Tsar Alexander I of Russia
Alexander I of Russia
Alexander I of Russia , served as Emperor of Russia from 23 March 1801 to 1 December 1825 and the first Russian King of Poland from 1815 to 1825. He was also the first Russian Grand Duke of Finland and Lithuania....

 a plan to build a tunnel under the river Neva in St Petersburg. This scheme was turned down (a bridge was built instead) but Brunel continued to develop ideas for new methods of tunnelling.

Brunel and Thomas Cochrane
Thomas Cochrane, 10th Earl of Dundonald
Admiral Thomas Cochrane, 10th Earl of Dundonald, 1st Marquess of Maranhão, GCB, ODM , styled Lord Cochrane between 1778 and 1831, was a senior British naval flag officer and radical politician....

 patented the tunnelling shield
Tunnelling shield
A tunnelling shield is a protective structure used in the excavation of tunnels through soil that is too soft or fluid to remain stable during the time it takes to line the tunnel with a support structure of concrete, cast iron or steel...

, a revolutionary advance in tunnelling technology, in January 1818. In 1823 Brunel produced a plan for a tunnel between Rotherhithe and Wapping, which would be dug using his new shield. Financing was soon found from private investors including the Duke of Wellington
Arthur Wellesley, 1st Duke of Wellington
Field Marshal Arthur Wellesley, 1st Duke of Wellington, KG, GCB, GCH, PC, FRS , was an Irish-born British soldier and statesman, and one of the leading military and political figures of the 19th century...

 and a Thames Tunnel Company was formed in 1824, with the project beginning in February 1825.

The first step taken was the construction of a large shaft on the south bank at Rotherhithe, 150 feet (46 m) back from the river bank. It was dug by assembling an iron ring 50 feet (15 m) in diameter above ground. A brick wall 40 feet (12 m) high and 3 feet (91 cm) thick was built on top of this, with a powerful steam engine surmounting it to drive the excavation's pumps. The whole apparatus was estimated to weigh 1,000 tons. The soil below the ring's sharp lower edge was removed manually by Brunel's workers. The whole shaft thus gradually sank under its own weight, slicing through the soft ground rather like an enormous pastry cutter. The shaft became stuck at one point during its sinking as the pressure of the earth around it held it firmly in position. Extra weight was required to make it continue its descent; a total of 50,000 bricks were added as temporary weights. It was realised this problem was caused because the shaft was cylindrical; years later when the Wapping shaft was built, it was slightly wider at the bottom than the top. This non-cylindrical tapering design ensured it did not get stuck. By November 1825 the Rotherhithe shaft was in place and tunnelling work could begin.

The tunnelling shield, built at Henry Maudslay
Henry Maudslay
Henry Maudslay was a British machine tool innovator, tool and die maker, and inventor. He is considered a founding father of machine tool technology.-Early life:...

's Lambeth
Lambeth
Lambeth is a district of south London, England, and part of the London Borough of Lambeth. It is situated southeast of Charing Cross.-Toponymy:...

 works and assembled in the Rotherhithe shaft, was the key to Brunel's construction of the Thames Tunnel. The Illustrated London News described how it worked:

Each of the twelve frames of the shield weighed over seven tons. The key innovation of the tunnelling shield was its support for the unlined ground in front and around it to reduce the risk of collapses. However, many workers, including Brunel himself, soon fell ill from the poor conditions caused by filthy sewage laden water seeping through from the river above. This sewage gave off methane gas which was ignited by the miner's oil lamps. When the resident engineer, William Armstrong, fell ill in April 1826 Marc's son Isambard Kingdom Brunel
Isambard Kingdom Brunel
Isambard Kingdom Brunel, FRS , was a British civil engineer who built bridges and dockyards including the construction of the first major British railway, the Great Western Railway; a series of steamships, including the first propeller-driven transatlantic steamship; and numerous important bridges...

 took over at the age of 20.

Work was slow, progressing at only 8–12 feet a week (3–4 m). To earn some income from the tunnel, the company directors allowed sightseers to view the shield in operation. They charged 1 shilling for the adventure and an estimated 600–800 visitors took advantage of the opportunity every day.

The excavation was also hazardous. The tunnel flooded suddenly on 18 May 1827 after 549 feet (167.3 m) had been dug. Isambard Kingdom Brunel
Isambard Kingdom Brunel
Isambard Kingdom Brunel, FRS , was a British civil engineer who built bridges and dockyards including the construction of the first major British railway, the Great Western Railway; a series of steamships, including the first propeller-driven transatlantic steamship; and numerous important bridges...

 lowered a diving bell
Diving bell
A diving bell is a rigid chamber used to transport divers to depth in the ocean. The most common types are the wet bell and the closed bell....

 from a boat to repair the hole at the bottom of the river, throwing bags filled with clay into the breach in the tunnel's roof. Following the repairs and the drainage of the tunnel, he held a banquet inside it.

1828

The tunnel flooded again the following year, on 12 January 1828, when six men died and Isambard himself narrowly escaped drowning. Isambard was sent to Brislington, near Bristol to recuperate where he heard about the competition to build what became the Clifton Suspension Bridge
Clifton Suspension Bridge
Brunel died in 1859, without seeing the completion of the bridge. Brunel's colleagues in the Institution of Civil Engineers felt that completion of the Bridge would be a fitting memorial, and started to raise new funds...

.

Financial problems followed, leading in August to the tunnel being walled off just behind the shield. The tunnel was abandoned for seven years.

Re-opening

In December 1834 Marc Brunel succeeded in raising sufficient money (including a loan of £247,000 from the Treasury
HM Treasury
HM Treasury, in full Her Majesty's Treasury, informally The Treasury, is the United Kingdom government department responsible for developing and executing the British government's public finance policy and economic policy...

) to continue construction.

Starting in August 1835 the old rusted shield was dismantled and removed. By March 1836 the new shield (improved and heavier) was assembled in place and boring resumed.

Impeded by further floods, (23 August 1837, 3 November 1837, 20 March 1838, 3 April 1840) fires and leaks of methane
Methane
Methane is a chemical compound with the chemical formula . It is the simplest alkane, the principal component of natural gas, and probably the most abundant organic compound on earth. The relative abundance of methane makes it an attractive fuel...

 and hydrogen sulphide
Hydrogen sulfide
Hydrogen sulfide is the chemical compound with the formula . It is a colorless, very poisonous, flammable gas with the characteristic foul odor of expired eggs perceptible at concentrations as low as 0.00047 parts per million...

 gas, the remainder of the tunnelling was completed in November 1841, after another five and a half years. The extensive delays and repeated flooding made the tunnel the butt of metropolitan humour:
The Thames Tunnel was fitted out with lighting, roadways and spiral staircases during 1841–1842. An engine house on the Rotherhithe side, which now houses the Brunel Museum, was also constructed to house machinery for draining the tunnel. The tunnel was finally opened to the public on 25 March 1843.

Pedestrian usage

Although it was a triumph of civil engineering, the Thames Tunnel was not a financial success. It had cost a fortune to build—£454,000 to dig and another £180,000 to fit out—far exceeding its initial cost estimates. Proposals to extend the entrance to accommodate wheeled vehicles failed owing to cost, and it was only used by pedestrians. It became a major tourist attraction, attracting about two million people a year, each paying a penny to pass through, and became the subject of popular songs. The American traveller William Allen Drew commented that "No one goes to London without visiting the Tunnel" and described it as the "eighth wonder of the world". When he saw it for himself in 1851, he pronounced himself "somewhat disappointed in it" but still left a vivid description of its interior, which was more like an underground marketplace than a transport artery:
Drew was perhaps charitable in his view of the tunnel, which came to be regarded as the haunt of prostitutes and "tunnel thieves" who lurked under its arches and mugged passers-by. The American writer Nathaniel Hawthorne
Nathaniel Hawthorne
Nathaniel Hawthorne was an American novelist and short story writer.Nathaniel Hawthorne was born in 1804 in the city of Salem, Massachusetts to Nathaniel Hathorne and the former Elizabeth Clarke Manning. His ancestors include John Hathorne, a judge during the Salem Witch Trials...

, writing in 1855, took a much more negative view of the tunnel when he visited it a few years after Drew:

Use as a railway tunnel

No doubt to the relief of the tunnel's investors, it was purchased in September 1865 by the East London Railway Company, a consortium of six mainline railways which sought to use the tunnel to provide a rail link for goods and passengers between Wapping (and later Liverpool Street
Liverpool Street station
Liverpool Street railway station, also known as London Liverpool Street or simply Liverpool Street, is both a central London railway terminus and a connected London Underground station in the north-eastern corner of the City of London, England...

) and the South London Line
South London Line
South London Line may refer to one of two semicircular railway lines which both run between London Victoria and London Bridge stations through the southern suburbs of London, UK:*Inner South London Line - running via Denmark Hill and Peckham Rye...

. The tunnel's generous headroom, resulting from the architects' original intention of accommodating horse-drawn carriages, provided a sufficient loading gauge
Loading gauge
A loading gauge defines the maximum height and width for railway vehicles and their loads to ensure safe passage through bridges, tunnels and other structures...

 for trains as well. The first train ran through the tunnel on 7 December 1869. In 1884, the tunnel's disused entrance shafts in Wapping and Rotherhithe were converted into Wapping
Wapping tube station
Wapping railway station is on the northern bank of the river Thames in Wapping, East London, England. It is in Zone 2, and on the East London Line of London Overground between and ....

 and Rotherhithe
Rotherhithe tube station
Rotherhithe railway station is a railway station on the southern bank of the river Thames at Rotherhithe, London, England. It is on London Overground's East London Line, between and , and is in Zone 2...

 stations respectively.

The East London Railway was later absorbed into the London Underground
London Underground
The London Underground is a rapid transit system serving a large part of Greater London and some parts of Buckinghamshire, Hertfordshire and Essex in England...

, where it became the East London Line
East London Line
The East London Line is a London Overground line which runs north to south through the East End, Docklands and South areas of London.Built in 1869 by the East London Railway Company, which reused the Thames Tunnel, originally intended for horse-drawn carriages, the line became part of the London...

. It continued to be used for goods services as late as 1962. During the Underground days, the Thames Tunnel was the oldest piece of the Underground's infrastructure.

In 1995 the tunnel became the focus of considerable controversy when it was closed for long-term maintenance. Its condition had deteriorated so severely that London Underground management publicly declared that, if it could not be repaired, the entire East London Line would have to be permanently closed. However, the proposed repair method was to seal it against leaks by "shotcreting
Shotcrete
Shotcrete is concrete conveyed through a hose and pneumatically projected at high velocity onto a surface, as a construction technique....

" it with concrete, obliterating its original appearance. This led to a bitter conflict with architectural interests wishing to preserve the tunnel's appearance and disputing the need for the treatment.

Following an agreement to leave a short section at one end of the tunnel untreated, and more sympathetic treatment of the rest of the tunnel, the work went ahead and the route reopened – much later than originally anticipated – in 1998. The tunnel closed again from 23 December 2007 in order to permit tracklaying and resignalling for the East London Line extension
East London line extension
The East London line extension project is a British railway engineering project in London, managed by Transport for London. The project involves extending the East London Line and making it part of the mainline London Overground network...

. The extension work resulted in the tunnel becoming part of the new London Overground
London Overground
London Overground is a suburban rail network in London and Hertfordshire. It has been operated by London Overground Rail Operations since 2007 as part of the National Rail network, under the franchise control and branding of Transport for London...

. After its reopening on 27 April 2010, it is used by mainline trains again.

Influence

The construction of the Thames Tunnel showed that it was indeed possible to build underwater tunnels, despite the previous scepticism of many engineers. Several new underwater tunnels were built in the UK in the following decades: the Tower Subway
Tower Subway
The Tower Subway is a tunnel, dug in 1869, beneath the River Thames in central London, close to the Tower of London. Its alignment runs between Tower Hill on the north side of the river and Vine Lane to the south...

 in London; the Severn Tunnel
Severn Tunnel
The Severn Tunnel is a railway tunnel in the United Kingdom, linking South Gloucestershire in the west of England to Monmouthshire in south Wales under the estuary of the River Severn....

 under the River Severn
River Severn
The River Severn is the longest river in Great Britain, at about , but the second longest on the British Isles, behind the River Shannon. It rises at an altitude of on Plynlimon, Ceredigion near Llanidloes, Powys, in the Cambrian Mountains of mid Wales...

; and the Mersey Railway Tunnel under the River Mersey
River Mersey
The River Mersey is a river in North West England. It is around long, stretching from Stockport, Greater Manchester, and ending at Liverpool Bay, Merseyside. For centuries, it formed part of the ancient county divide between Lancashire and Cheshire....

. All were built using refinements of Brunel's tunnelling shield, with James Henry Greathead
James Henry Greathead
James Henry Greathead was an engineer renowned for his work on the London Underground railway.-Early life:Greathead was born in Grahamstown, South Africa; of English descent, Greathead's grandfather had emigrated to South Africa in 1820. He was educated at St Andrew's College, Grahamstown, and the...

 playing a particularly important role in developing the technology. The historic importance of the tunnel was recognised on 24 March 1995, when the structure was listed Grade II* in recognition of its architectural importance. A plaque could be seen above the stairs descending to the Rotherhithe platforms before the temporary closure. The plaque has been removed for safe keeping for the duration of the works.

Visiting

Nearby in Rotherhithe, the original Brunel Engine House is open to visitors as the Brunel Museum. It was originally built to house the draining pumps for the tunnel and has now been restored. Until the East London Line was closed in 2008 for major refurbishment and upgrade, the museum used to organise tours through the tunnel by train.

The final opportunity for pedestrian access to the tunnel was for two days in March 2010 as part of London's "East" arts festival.

External links

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