HS2 have just released a video along with pictures of what is clearly work to build the long awaited ventilation services facility at Stephenson Place to the south of the HS2 site. This, as some will know, entailed the building of a quite controversial building which will help to ventilate the Northern line as well as doubling as a new substation too in order to power its trains.. That structure hasn’t yet been built because much of the work so far has been the construction of the necessary tunnels to form the new system.
The video tweet depicted below basically shows the work in a nutshell. The tunnels are 20 metres below the surface and its said digging these meant some very narrow margins had to be worked with. Its not said exactly what lines were close to the works but there’s no doubt the Victoria and Northern line tubes were the tunnels in question. Not only that the main power routes from the National Grid system to LUL’s substations (eg the Bulk Supply Points – BSPs – which I have written about elsewhere) would have also caused some difficulty as well as things such as the Thames Water Mains that HS2 does mention in their video.
HS2 also released some photographs of the work this week. It might not be realised however TfL supremo Andy Byford was given a tour of the works this week too – because after all, these tunnels are going to be his authority’s responsibility once the work is completed. It’ll be TfL’s task (as London Underground Limited) to fit these structures out including ventilation and electricity equipment as well as staff mess rooms, service stairs, monitoring equipment and the rest of it.
The controversial headhouse in Stephenson Place. Source: Twitter.
View looking south down the new service tunnels. Source: Twitter.
TfL supremo Andy Byford has a tour of the new tunnels. The location is the bottom of the shaft beneath the ‘acoustic shed’ in Melton Street. Source: Twitter.
TfL supremo Andy Byford in group pose with HS2 Ltd CEO Mark Thurston and construction staff. One can see from this picture the state of work is now far more advanced than what’s shown in the video. Source: Twitter.
Screencap from HS2’s new film showing the Stephenson Way shaft worksite. The view looks north west towards Cobourg Street. Its evident the shaft was not fully dug at the time of filming.
According to the HS2 master documents the work should have begun in late 2018 with completion scheduled for late Autumn 2020. The works didn’t even begin until I think late October 2021 (as the ‘acoustic shed’ discussed in the film) wasn’t built until that month as my photographs show. I don’t think the project will be completed this year but rather sometime in the first half of 2023, which would mean a slippage of nearly three years.
It must be remembered the entire Euston HS2 project has been rescheduled in terms of how it is to be constructed – there is one modified phase now rather than two phases – and that’s with a slightly later completion date in the 2030s – thus the lateness of the current ventilation/power supply tunnel work isn’t really going to cause any adverse effect.
Some work on the Stephenson Street site had begun before lockdown in early 2020, including preparing the site for the new construction shaft there.
The new acoustic shed as HS2 calls it in their video – seen in an incomplete state during the second week of October 2021.