Engineers have completed phase one of National Grid’s flagship Tunnel under the River Thames.
The project forms a critical part of National Grid Gas Distribution’s vital work to future-proof London’s gas infrastructure for the 21st century and involves three of London’s most famous locations: the Royal Hospital Chelsea, Battersea Park and the River Thames.
Work recently finished on the project’s first phase, a 30m shaft which has been sunk in the grounds of the Royal Hospital Chelsea. The site has now been cleared to make sure the project doesn’t disrupt local events, such as the Chelsea Flower Show.
Engineers are now shifting their focus to Battersea Park, where another 30m deep shaft will be sunk. Work on this is scheduled to be completed in August 2017 after which tunnelling under the River Thames will begin.
A micro tunnel boring machine (TBM) remotely controlled by an above ground operator will be used to carve out the 330m long tunnel. The tunnelling phase of the project is expected to be completed sometime in 2018 after which the new intermediate pressure gas pipe will be installed.
Andy Hickling, the Director of Estates, Facilities and Quartermaster at the Royal Hospital Chelsea, said: “We fully understand the importance of this project but initially we did have concerns that a project of this scale could adversely impact the major events we hold such as the Chelsea Flower Show, Masterpiece and the Global Champions Tour.
“I’m pleased to report that these concerns have not materialised and we could not have wished for a more cooperative and highly professional workforce.”
He added: “The Hospital is not only looking forward to our events season but to welcoming back National Grid Gas Distribution to complete the project.”
Project Manager Andrew Hejdner said: “I’d like to thank the Royal Hospital Chelsea and its residents for their patience and understanding over the past few months while we’ve been carrying out work in their grounds.
“Our team have got to know many of the residents some of whom served as military engineers or who went onto become engineers after leaving the forces,
“We’ve had some fascinating conversations with them and it turned out that one of the guys had worked on the Channel Tunnel project.”
To get to this stage the project team has had to do a huge amount of work. This has included discussions with 15 different organisations, securing 20 different permissions, working around other major projects such as Thames Tideway and ensuring local events such as the Chelsea Flower Show and arts fair Masterpiece were not affected by the project.
Mr Hejdner explained: “We’re working to a very tight schedule and we had to be off the Royal Hospital site by the end of March to make sure events such as the Chelsea Flower Show weren’t affected by our project.
“I’m delighted to say that we’re proceeding according to schedule thanks to the hard work and commitment of our project team.”
The project is being delivered by National Grid Gas Distribution’s strategic partner tRIIO, which also includes contractors Mott Macdonald and Skanska. The tunnel is part of National Grid’s £1billion investment in replacing ageing gas mains across the capital.