The Thames Tunnel

As London expanded eastwards in the early 19^th century, with the opening of new docks on both sides of the Thames, a means of crossing the river was badly needed downriver of London Bridge. A bridge was out of the question because it would need to be of enormous height for ships’ mast to pass under. Various tunnels had been constructed by canal engineers but a tunnel under a river had never been successfully achieved anywhere in the world. It was the engineering genius of two men, father and son, that created the solution.

Throughout the 19^th century there was a growing complex of docks on both the north and south sides of the Thames to the east of London. However, there was no dry crossing downriver of London Bridge by which to travel from one side to the other. It was observed that goods arriving at the new docks being constructed on the north side had to make a lengthy journey westwards through narrow streets, then pay a toll to cross London Bridge, to reach Southwark and Rotherhithe on the south side. The bridge was very congested, with an estimated 4,000 vehicles each day struggling to cross. It was said that it cost more to carry a cargo of skins over the Thames from Wapping than to transport it across the Atlantic from Hudson’s Bay. The river was often congested with ships and not easy to cross by boat. The ideal solution would be a tunnel but machinery and expertise to create an underground thoroughfare did not yet exist.

The idea of a tunnel under the Thames to link one bank with the other was first seriously considered at the end of the 18^th century, even before the creation of the docks. Ralph Dodd is a name that often crops up as a promoter of docks, bridges and canals in various parts of the country at around that time. Some of his proposed schemes came to fruition, such as the Grand Surrey Canal, Vauxhall Bridge, and Waterloo Bridge, although not necessarily with his involvement to their conclusion. Prior to those projects he had embarked on a scheme to build a tunnel under the Thames from Tilbury to Gravesend. In addition to the movement of goods, such a resource was considered advantageous for troop movements at the time when Britain was at war with Napoleonic France and under threat of invasion. A tunnel between the ordnance depot at Tilbury Fort and the busy maritime town of Gravesend therefore seemed ideal. A report in The Times in July 1798 explained that the tunnel would save a land journey of 50 miles between those two points and cost an estimated £15,995. The project gained the approval of senior military men and a series of public meetings were held. Following the first, at Gravesend chaired by local landowner the Earl of Darnley, a committee was formed that included three Members of Parliament. A company was launched at a meeting in the Strand in London in November 1798. Thirty thousand pounds was raised in share sales by February of the following year and Samuel Wyatt was engaged as a consultant. Royal assent was given by King George III in July 1799.

Work began with a tunnel sunk close to a chalk pit near Gravesend, overseen by Colonel Twiss, Wyatt and a miner by the name of Ludlam. Things did not go well from the beginning. A shaft of 10 feet in diameter became so flooded at 42 feet in depth that a steam pump had to be employed to drain it. Each time the pump was turned off the shaft flooded within an hour. By June 1802 the flooding was so bad that a survey was requested from the engineer John Rennie, who made suggestions but declined to give an opinion on the practicality of the scheme. Work was temporarily halted in October when the engine house burnt down. In December the shaft reached 85 feet in depth. At that point, having cost more than £15,200, the project was abandoned.

The idea of a tunnel under the Thames became increasingly important. The West India Docks, London Docks, and East India Docks opened on the north bank of the river during the first decade of the 19^th century. On the opposite bank there were the naval arsenals at Woolwich and Deptford and the growing dock complex at Rotherhithe. Even before Ralph Dodd’s project had been abandoned the Cornish engineer Robert Vazie was proposing a tunnel further upstream between Rotherhithe and Limehouse, which would be ideal to link the dock and naval complexes on each side. He dug shafts on both sides of the river and reported the cost would be lower than first expected, £140,000 was raised, and the Thames Archway Company formed. An Act of Parliament was given royal assent in July 1805.

The tunnel was designed for the use of pedestrians, horses and carriages. A team of Cornish miners was brought to London to carry out the work. The first shaft was sunk near Lavender Lane at Rotherhithe. From there the plan was to drive a miners’ drift passage under the river about five feet high and wide enough for two men to pass. The main tunnel would then be created above it, with the pilot tunnel acting as a drain, a method that had recently been employed in the creation of the Blisworth Tunnel on the Grand Junction Canal. The Rotherhithe shaft quickly filled with water and Vazie ordered a powerful pump. Instead the company directors would only authorize a much less powerful machine. As the miners dug deeper the pump proved inadequate and work came to a halt.

Costs were exceeding budget, work was suspended, and John Rennie’s advice was once again sought, together with William Chapman, another canal engineer. They gave contradictory opinions so the company brought in Davies Giddy, a Cornish Member of Parliament and he recommended bringing his friend Cornish mining engineer and pioneer of steam locomotion Richard Trevithick (who was already working in London), to take charge of the project. Relations between Trevithick and Vazie were not harmonious and in October 1807 the latter was dismissed from the venture. By then the tunnel under the Thames stretched for nearly 400 feet. There was some sympathy for Vazie, who had been working on the project for four and a half years, and Trevithick often found himself at odds with the directors. In January 1808 the tunnel was a thousand feet long. Trevithick was in the far end with one of the workers when quicksand caused water to suddenly flood in. It was soon above their shoulders but they managed to swim to the exit. Shortly after there was another flood and the directors called an emergency meeting at Limehouse. They had lost confidence in Trevithick and offered £500 pounds to anyone who could propose a scheme to finish the work. Despite a large response they decided to throw in the towel and the company was wound up.