Marc Isambard Brunel is often overshadowed by his son Isambard Kingdom Brunel, but it is to both that we owe the Thames tunnel at Rotherhithe. The vision and initiation was Marc’s but it took Isambard to finish it after 18 long years of construction.
At the beginning of the nineteenth century major docks on the Thames included those at Wapping, Blackwall, Surrey and the Isle of Dogs. Most of these were up to four miles downstream of the nearest crossing point at London Bridge. As well as this trading bottleneck, there was also a military disadvantage of having to reinforce the vulnerable County of Kent over a congested bridge in the centre of a major city. Any bridge built lower down the river would have to be of a height to allow ships to pass beneath or with a moveable section. Neither solution was easy from an engineering perspective.
A tunnel was the obvious solution but the ground was soft and presented its own problems of stability and water penetration. The same factors explain the comparative paucity of tube tunnels to the south of the river. Marc Brunel’s approach was to build the tunnel from a travelling ‘shield’ with the miners working the face from small panels which were only exposed one section at a time. A circular or rectangular ring of wood or iron held the tunnelled ground at bay until supporting brickwork was constructed behind this moving shield. The design was allegedly inspired by the shipworm and in 1818 Marc took out a patent for the ‘Forming of Drifts and Tunnels Underground’.
On 24th June 1824, the Bill for ‘Making and Maintaining a Tunnel under the Thames’ was given Royal Assent. The tunnel was to connect Rotherhithe and Wapping and would be 396 metres long. Marc had lobbied hard to gain approval – a key supporter was the Duke of Wellington. The construction aim was for the tunnel to follow the narrow clay band between the quicksand below and the gravel beds above. This brought the roof of the tunnel perilously close to the river bed, as subsequent events would sadly prove. Construction started on the south bank at Rotherhithe in March 1825 when a shaft was sunk by constructing a cylinder of bricks that sank under its own weight. Boring of the tunnel itself commenced in November of the same year and that is when the troubles began.
Shortly after work started Marc became ill and his son Isambard became involved with the project. At the tender age of 20, Isambard soon became resident engineer. By 1827, steady progress was being made and, in the absence of twentieth century Health and Safety rules, members of the public were admitted to marvel at the engineering. In April, for example, over 700 were admitted at one shilling (5p) each. In May 1827 the first flood occurred when water broke through from the Thames above and flooded the workings. Fortunately no lives were lost but this record was not to be maintained. sambard’s response to this influx was to fill the hole from the river above with iron bars and clay, using a diving bell to monitor operations. The tunnel was then able to be pumped out and work recommenced.
Marc suffered a stroke in August 1827 and never enjoyed good health thereafter. After re-opening, a ‘Celebration Banquet’ was held underground in November 1827. This celebration turned out to be more than a little premature as just two months later the second flooding took place, this time injuring Isambard himself and killing six workmen. In August of the same year, the money ran out, work was halted and the tunnel itself was bricked up.
It was fully seven years later that funds were raised to allow work to continue. Both Brunels remained involved but Isambard was by now busy with the surveying of the Great Western Railway and the position of Chief Engineer went instead to Richard Beamish. A new and larger tunnelling shield was installed and excavations continued in 1835. Thomas Page in turn took over the position of Chief Engineer in 1836. Over the next three years a further three floods took place: on each occasion the river bed had to be plugged and the tunnel pumped dry. In addition, explosions from fire damp (methane) became a regular occurrence. As the marathon neared completion, Marc was knighted in 1840 and in 1842 work commenced on the shaft on the north side. It had, in all respects, been a Wapping project.
The tunnel was finally opened in 1843 as a foot tunnel with visitors descending staircases within the shafts. The original plan was to have had ramps for vehicular traffic but these were never constructed; the tunnel thus became a novelty attraction rather than the transport thoroughfare initially projected. In the first ten days, a staggering 100,000 visitors passed through the tunnel for a toll of a penny (0.4p) each. By fifteen weeks the visitors had exceeded one million (London’s population was around two million at this time). For several years the tunnel remained a popular attraction but, despite the introduction of fairs and fire-eaters, stalls and sword-swallowers, by 1860 the tunnel was run down and populated by vagrants. The railway age had by then produced its own engineering marvels and it was the railways that were to prove the tunnel’s salvation.
In 1865 the tunnel was taken over and re-used by the East London Railway as part of their network and opened to traffic in 1869. The line was taken over by London Underground and became part of the Metropolitan Line - East London Branch. In 20109 theoperator changed again and it becae part of London Overground. Prior to this last re-opening, the public were allowed to walk through the tunnel.
The original Brunel engine house and adjacent Grand Shaft on the southern side of the tunnel is now run as the Brunel Museum and is well worth a visit. In 2014, Subterranea Britannica celebrated its 40th anniversary with a banquet in the Grand Shaft for 80 members. This emulated in a small way the celebratiions of 1827. Today access to the shaft has been improved and performances also take place underground.
Based in part on The Brunels’ Tunnel edited by Eric Kentley, the publication of which was partially sponsored by Sub Brit.