Crossrail’s ‘race against the clock’ to complete a key part of its work to the Victorian Connaught Tunnel in the east of London has been completed ahead of schedule. This forms part of the largest infrastructure project being undertaken in Europe at the moment.

Earlier in the year, dam walls were installed in a section of the Royal Docks that runs above the tunnel to allow Crossrail workers to access the tunnel from above. However, the dam had to be removed by the first week of September to allow ships to pass through the dock ahead of a trade exhibition at ExCeL London. Following three months of work around the clock, the work has now been completed, the dam walls have been removed and the dock has been re-opened. A cofferdam the size of a football pitch was installed and 13 million litres of water were drained from the Royal Docks. This allowed workers to deepen, widen and strengthen the central section of the tunnel so that it can accommodate new Crossrail trains. Sections of the tunnel were in a poor condition and parts of it were narrowed during the 1930s so that the dock could be deepened to accommodate larger ships with brickwork removed and steel segments installed. This material has now been removed and a larger, stronger structure has been put in place in preparation for the start of Crossrail services in 2018.The tunnel was built in 1878 and has not been in passenger use since December 2006. It is the only existing tunnel that will be re-used for Crossrail.

“In refurbishing this Victorian rail tunnel, the team at Connaught has had to think on its feet and overcome some unique challenges. It is a source of great pride that our engineers and everyone on the project continue to deliver, often in difficult and complex circumstances,” says Andrew Wolstenholme, Crossrail chief executive.

Linda Miller, Connaught Tunnel Project Manager explains that “It was a race against the clock to get the work completed and the dock re-flooded, so it’s great news that we’ve got it finished ahead of schedule. It’s been a fantastic effort by the whole team to get the job done safely, quickly and effectively.”

When the southeast section of Crossrail opens, up to 12 trains an hour in each direction will run through the Connaught Tunnel, reducing journey times and supporting the wider regeneration of the Royal Docks. With Crossrail, the journey from Abbey Wood to Bond Street will be around 20 minutes quicker and passengers travelling to Heathrow will be able to cut around 40 minutes off their journey.As well as widening and deepening the central section of the tunnel, the work at the site will include laying new tracks, waterproofing, installing water pumps and cleaning the 135 years of coal and soot from the bricks.The total funding envelope available to deliver Crossrail is £14.8bn.

The Crossrail route will pass through 38 stations and run more than 100km from Maidenhead and Heathrow in the west, through new twin-bore 21 km tunnels below central London to Shenfield and Abbey Wood in the east.

When Crossrail opens it will increase London’s rail-based transport network capacity by 10%, supporting regeneration and cutting journey times across the city. Crossrail services are due to commence through central London in 2018.