Beneath the streets of the British capital, over 70 million working hours have been put into the largest construction project in Europe. The current construction of the new London Crossrail tunnel project is underway and is expected to provide a 100km route from the west of the capital to the east.
The new Crossrail Tunnel project will run from Heathrow and reading in west London, all the way through to Shenfield and Abbey Wood in the east. The project is set to transform London’s rail transport network by increasing capacity by 10%, cutting journey times and also supporting economic regeneration within the city.
The new Crossrail tunnel project system will enable access for an additional 1.5 million people to the capital within 45 minutes, further enabling economic development in London’s key employment, business and leisure sectors.
Construction of the Crossrail tunnel project poses major beneficial factors for the 750,000 workers who already commute inside of the capital. The project will provide new interchanges that are strategically placed to benefit national, local and international leisure and business travellers.
The Crossrail tunnel project will host 40 stations, which include 10 new stations at Paddington, Bond Street, Tottenham Court Road, Farringdon, Liverpool Street, Whitechapel, Canary Wharf, Custom House, Woolwich and Abbey Wood. These additional stations will open up further access to London residents as well as work based commuters outside of the capital.
During the construction of the Crossrail tunnel project there were major concerns that arose around the safety of London’s crucial sewage and drainage networks. These drainage systems are key to the networking of all of London’s sewage and water and would hold devastating consequences for the city if they were to be damaged.
One of the main areas of concern was the construction based around the Blackwall tunnel site. After carrying out a CCTV drain survey of the sewers during the preparatory work for the project, engineers discovered that the tunnel boring machines would pass close beneath two major sewer lines, the Ham sewer and the Wick sewer, based in the area alongside the northern approach to the Blackwall tunnel.
The upkeep and maintenance of the Ham Sewer are of strategic importance to East London as two million businesses and residents rely on the continual flow of this sewage network. Normal maintenance such as drain clearance would normally not be an issue in the Ham sewer, but if it was to sustain any serious damage through the construction of the Crossrail tunnel project, fixing the problem could prove to be more of a challenge than your average drain repair job.
The Crossrail tunnel project subcontracted private engineers to search for similar problems on a global scale in order to find a resolution, out of 25 projects world wide, none came close to the limited parameters in which the Crossrail tunnel project faced, this was considered to be the closest pass by a tunnel to a key and sensitive structure by far.
Through the use of traditional blocked drain methods, surveyors and engineers began to collect data and information on the sewage network, mainly through the use of CCTV drain surveys and laser burst technology.
This information was then utilised by Crossrail tunnel project engineers to develop a solution for the problem, in which engineers believed that lining the sewage network with steel would stiffen the structure, making the ground movements created by the large tunnel boring machines obsolete, thus minimising the possibility of damage to the sewer network’s masonry foundations.
At Total Drainage we always are amazed to see such innovation in tunnel and drain construction; projects like this are pushing the boundaries and barriers within this industry and we will keep you updated on developments with the project.