What Is The Silvertown Tunnel?

By M@

Last Updated 20 December 2023

What Is The Silvertown Tunnel?
The North Greenwich portal to the Silvertown Tunnel.
The North Greenwich portal to the Silvertown Tunnel. Image TfL

The Silvertown Tunnel is often in the news. Here's our guide to what it is, why it was built, and how to use it.

What is the Silvertown Tunnel?

It will be a pair of road tunnels beneath the Thames connecting North Greenwich to the western end of Silvertown in the Royal Docks. They'll connect to the A1020 Silvertown Way/Lower Lea Crossing to the north, and feed into the Blackwall Tunnel Southern Approach road to the south. It's easier to understand on a map, which is why we embed this ⬇️

Map showing the route of the Silvertown Tunnel
Zoomable version on Wikipedia

Why is it being built?

The nearby Blackwall Tunnels are frequently congested or blocked, leading to long, polluting tailbacks. The Silvertown Tunnel will provide extra capacity, and add redundancy that will help if the existing tunnels are blocked (happens almost daily). The scheme will also open up more bus routes across the river.

When will it open?

Transport for London awarded Riverlinx Consortium the contract in 2018, and construction began in March 2021. As things stand, the tunnel is due to open in 2025.

A tunnel boring machine at its start point for the Silvertown Tunnel
Tunnel boring machine Jill in its launch chamber. Image: TfL

How much did it cost?

Construction of the tunnel is eating up something like £1.2 billion (2020 estimate). It'll then cost another estimated £1 billion over 25 years to pay for maintenance, financing and operation. Riverlinx paid up-front costs and will be paid back by TfL through money collected from tolls.

Tolls? Wait, what?

That's right. The new tunnel will require you to part with some pounds if you want to use it. Despite the consultation on this taking place a decade ago, the final details have yet to be publicised. We can expect something similar to the Dartford Crossing (currently £2.50 for cars etc, free for motorbikes/mopeds).

So won't everyone just use the Blackwall tunnels instead?

Nope. The currently free Blackwall tunnels will also be tolled. Whichever way you go, you'll have to spend money. That £1.2 billion construction debt would take decades to pay back if only one of the tunnels were tolled.

Who can use it?

Like Blackwall, the Silvertown tunnel is intended for motor vehicles only. No cycles, pedestrians, e-scooters, skateboards, pogo sticks...etc.

I don't have a car? Will I ever get to see this exciting new infrastructure?

You do have bus options, though they've been scaled back somewhat. Just two bus routes will run regular services through the tunnel. The existing 129 service will be extended from the existing terminus at North Greenwich up through the Royal Docks. A new "X239" service, part of the Superloop scheme and expected to actually be called the SL4, will also use the tunnel. Beware, though. That one's an express between Blackheath and Leamouth, and won't be stopping at North Greenwich. All buses through the tunnel will be zero emission.

What about horses? Can you ride a pony and trap through the tunnel?

You don't actually need to know, do you? You're only asking to be picky, and to catch us out. As far as we can tell, nothing's yet been announced on equine usage. However, horse-drawn vehicles were banned from the neigh-bouring Blackwall Tunnel in 1947, so I think we can rule out the clip-clop echo of hooves.

What will cyclists do?

In approving construction, the Mayor agreed to look at ways to improve cross-river cycling provision in the area. The only local option currently is to take a bike onto the cable car (which is actually free for cyclists to use before 9.30am). Once the tunnel's open, TfL plans to run a shuttle bus for the use of cyclists, and is currently consulting the public about the specifics. The proposal is to start with six timetabled buses per hour, and tweak this according to demand. "Feedback from the consultation will inform the final frequency, stop locations and route for the service to operate", we're told. The results and plan will be announced at the end of 2023.

What will pedestrians do?

You'll never be able to walk from North Greenwich to the north side of the river, though you can cross using the foot tunnel at what I'm tempted to call Regular Greenwich. That'll bring you out at the southern tip of the Isle of Dogs, mind, a long way from the Silvertown Tunnel. If you're on foot and desperately want to use the tunnel, then you'll be able to hop aboard one of the two bus routes that pass through. Otherwise, the cable car and Jubilee line may serve your needs.

And horse-riders?

Oh cock off.

A green cone shaped tower which will sit over the northern portal of the silvertown tunnel
The northern (Newham) portal. Image TfL.

Did anyone object to the Silvertown Tunnel?

Oh golly gosh, yes. The project has been one big burrow o'strife from the word go. The chief concerns are the obvious ones: the increased pollution and traffic that a major new tunnel are likely to bring, particularly to Greenwich. Traffic through the area just south of the peninsula is already pretty ghastly. And remember, the tunnel's construction costs will be partly recouped through tolls. So it's in the operator's interests to keep traffic high for years to come, in order to keep the coins flowing.

Opposition has come from all political quarters, with No to Silvertown Tunnel and Stop the Silvertown Tunnel Coalition leading the charge. Friends of the Earth, Extinction Rebellion and numerous academics have also drawn attention to the expected environmental impact.

TfL would counter that, by providing contingency, the new tunnel will greatly reduce the number of idling vehicles at the oft-jammed Blackwall tunnels. Voila, less emissions overall. Campaigners would counter-counter argue that TfL should be focussing on reducing car use, by running trams or light railway through the new tunnel. TfL would counter-counter-counter argue that this would have less impact on the Blackwall situation, and would never pay off the construction overheads. And so the debate rumbles on. Barring some hugely unlikely volte face, the tunnel will open as planned in 2025 for motor vehicles only.

So the public-transport horse has now bolted?

Enough with your horses already!

The official TfL page for the Silvertown Tunnel can be found here, with further information.