Silvertown Tunnel Easing Congestion, TfL Says
The title of this post, is the same as that of this article on the BBC.
This is the sub-heading.
Transport for London (TfL) has shared the first insights about the impact on traffic of the new Silvertown Tunnel, as part of commissioner Andy Lord’s latest report to the TfL Board.
These two initial paragraphs gives a summary of about three weeks traffic.
Analysis of data between 21 April and 11 May shows the Silvertown and Blackwall tunnels are being used by an average of about 88,000 vehicles on a typical weekday. Of these, about 20,000 are using the Silvertown Tunnel.
Before the tunnel opened on 7 April, about 100,000 vehicles used the Blackwall Tunnel on weekdays.
TfL are claiming that this 12,000 drop in traffic is helping to ease congestion.
Logically, a drop in traffic will ease congestion, but the BBC article also says this.
However, it said it was aware of some increased traffic volumes at other river crossings, including the Woolwich Ferry.
The only other river crossings in the area are the Rotherhithe Tunnel and the Woolwich Ferry, both of which are free to all users.
So is the drop in traffic through the Blackwall and Silvertown Tunnels, due to drivers objecting to paying a toll and taking a free route instead?
On The Buses
The BBC article says this about bus passengers.
Mr Lord’s report also provided ridership data about the three bus services that operate through both tunnels: the new Superloop SL4, the extended route 129 and the 108, which already ran through the Blackwall Tunnel before 7 April.
Across the routes there is a daily average of more than 20,000 passengers making use of these services, of which typically about 7,000 are crossing the river using one of the two tunnels. In March 2025, there were about 2,700 crossings a day made using route 108.
The increase in bus passengers is not surprising.
Before the opening of the Silvertown Tunnel, there was just this bus service through the Blackwall Tunnel.
- London Bus 108 – Stratford and Lewisham via North Greenwich.
This has now been joined by, these bus services through the Silvertown Tunnel.
- London Bus 129 – Great Eastern Quay and Lewisham via City Airport and North Greenwich.
- London Bus SL4 – Canary Wharf and Grove Park via East India, Blackheath and Lee.
Note how the buses call at rail stations, an airport and other important traffic interchanges.
In Could The Silvertown Tunnel Handle More Buses?, I asked if buses through the Silvertown Tunnel should be increased?
Given that traffic through the combined Silvertown/Blackwall complex has dropped by 12,000 vehicles per day, that must leave space for a few buses or coaches.
- Assuming, that one bus or coach takes up the space of four cars, that would be space for 3,000 buses/coaches per day.
- Also assuming the bus and coach services are run on a twenty-four hour basis, that would be 125 buses/coaches per hour.
If the bus and coach services ran every ten minutes, that would say, there is space in the tunnel for up to a dozen new bus or coach routes.
There could develop a virtuous circle and feedback loop, which drives the tunnel to a state of equilibrium, where traffic grows through the tunnels, until it is maximised.
Consider.
- Research shows a bus route from A to B through the tunnel would attract passengers.
- Drivers and their passengers decide that on balance a bus ride is more convenient, no slower and more affordable than driving.
- Congestion charges and other charges for non-electric vehicles will play their part.
- Green issues will also will play their part.
- Fewer cars will use the tunnels.
- Increasing tunnel charges will only drive more car users to the buses.
- More free space in the tunnel, will allow more bus and coach routes.
- More bus and coach routes will attract drivers from their cars.
Eventually, equilibrium will be reached.
A similar effect happens, when a new bypass is opened and as if by magic it fills up.
When it happens with train services I call it, London Overground Syndrome.
On Your Bike
The BBC article says this about cyclists.
There is also a cycle shuttle service, enabling cyclists to take their bikes free of charge on a bus through the Silvertown Tunnel. TfL said some 100-150 people were using it on a typical day.
While this is below its capacity, TfL believes usage will grow as cyclists adapt their routes to benefit from this safer crossing option.
When I used to cycle around London in the 1970s, I never cycled under the Thames, but I did generally cycle as fast as I could across the city. I wouldn’t have put my bicycle on a free bus.
So, is this why the cycle shuttle service is below capacity?
The BBC article says this.
TfL believes usage will grow as cyclists adapt their routes to benefit from this safer crossing option.
I believe, that if TfL should ever charge for the cycle shuttle service, they’d kill it.
In my opinion, they’d be better off providing secure bike parking, but even some of that seems lightly used.
Tunnel Performance
The BBC article says this about tunnel charging and performance.
TfL said it intended to publish quarterly factsheets on the operational performance of the tunnels’ toll scheme.
This will include information about how many people pay the charge, the compliance rates for vehicles using the tunnels and the number of Penalty Charge Notices that are issued.
The first of these factsheets will be published later this year, but initial data shows that compliance has steadily increased, with about 90% of motorists either paying a charge or benefiting from an exemption.
Surprisingly, so far, I haven’t met anybody who has driven through the Silvertown Tunnel, except for a couple of bus drivers.
The Anonymous Widower 