What does a company do when it has three large construction sites in an urban area that need to move material around without clogging up the roads? They build a long conveyor belt network that goes over the heads of the roads and around the houses in the area.
This is HS2’s conveyor belt network, that’ll move muck dug out of the ground for the new Old Oak Common station and later the HS2 railway tunnels, across to a handling site where it can be loaded onto freight trains to remove.
The HS2 site, close to Willesden Green station will become Old Oak Common station, a huge HS2 station that’ll include 6 subterranean platforms for HS2 trains, and 8 platforms at the surface for the Elizabeth line and National Rail (GWR) services.
However, the area is also the construction site for a large crossover box that’ll allow trains to swap tracks, and is also the starting point for the tunnel boring machines that’ll dig the tunnels towards Euston.
Three large sites in a part of London that’s a mix of industrial and residential, and not keen on loads of lorries driving between the three locations. So, they’ve been building a large conveyor belt network between them.
From one end to the other is a mile as the bird flies, but to snake around the existing buildings, it’s 1.7 miles as the belt flows. Yesterday, it was formally switched on and started conveying muck away from the Old Oak Common station building site.
As the conveyor belts run around houses and over roads, they’ve been enclosed in a metal shield and each of the junction boxes is acoustically protected to reduce noise. There’s still a rumble from the machinery, but compared to the rest of the site, it’s pretty quiet.
The spoil being removed from the Old Oak Common station box is heavy London Clay, so it’s brought to the end of the conveyor belt where a machine breaks the clumps of spoil into smaller more even-sized lumps to be carried away on the belts.
Later, the conveyor belt will also carry away the spoil dug out for the crossover box being built at the Victoria Road site, and when tunnelling starts, will remove the spoil dug up by the Northolt Tunnel East tunnel boring machines when they are launched from the site in late 2023.
At the end of the conveyor is the Willesden Euroterminal site, where a fleet of freight trains carry the spoil away, to be used in landscaping sites in Cambridgeshire, Kent, and at Rugby.
The site at Willesden was chosen as it sits right next to the mainline railway, so they are able to bring freight trains onto the site, load them up and send them off. Each train can carry 1,500 tons of spoil away, which would have required about 70 lorries if they hadn’t been next to the railway.
They can run up to seven trains per day from the site, with two coming in to drop off the tunnel segment rings that’ll be needed next year.
The argument for building the conveyor is mainly to reduce road traffic, which in turn makes the local roads safer and quieter, but also cleaner as there’s less muck dropped on the roads as the lorries drive around. But the conveyor belt can also carry a lot more spoil faster than the lorries could have managed.
Everything is monitored from a control cabin, and the conveyor belt is expected to be in use until the middle of 2025.
The construction of the station box for the HS2 platforms is already underway, and they’re also preparing for the Great Western Main Line’s largest changes as the existing 4-track railway needs to be fanned out to accept eight platforms. That’ll see the railway rebuilt for about 2 kilometres on either side of the new station.
Fortunately, there’s space for that, and also the rail depot to the south that can be used as temporary diversions during the works. There will however be a point, where the old and new railway tracks need to be joined, and there’s likely to be some blockades in a few year’s time to allow that to happen.
The station is currently on target to be completed in 2030 — with a range of 2029 to 2033 to allow for problems, not just here at Old Oak Common, but along the rest of the railway to Birmingham. There is a contingency plan in the station design that could allow the GWR/Elizabeth line platforms to open sooner if there are delays to HS2 opening.
When it opens, apart from the huge capacity increase on regional and commuter lines created by shifting intercity trains onto HS2, the purpose of Old Oak Common is to relieve pressure on London Underground and Paddington station. It’s expected for example, that a lot of people who currently swap between the GWR and Elizabeth line at Paddington will find is easier to change at Old Oak Common instead. Likewise, people who might otherwise have caught HS2 into Euston only to then head out west can avoid London entirely by swapping services at Old Oak Common.
The intention is essentially to replicate the Stratford effect in east London on the Western side as well. Stratford is now a very busy interchange that gives people options to swap lines without going into central London, and when it opens, Old Oak Common will do the same for west London, and in doing so will improve the journeys for the millions of people who head to/from London to Birmingham and beyond when HS2 opens.
In the meantime though, a great big conveyor belt is rumbling around Willesden Junction to make it all happen.