The Silvertown Tunnel is no solution for the Blackwall Tunnel’s failures

Delays hit the Blackwall Tunnel

The Blackwall Tunnel closure caused gridlock across south-east London – but a new tunnel at this point is not a serious solution to these problems

It’s the nightmare that haunts hundreds of thousands of drivers. And it happened on Tuesday morning, right as the rush hour began. A mobile crane managed to shed a load of diesel and hydraulic fluid all over the northbound Blackwall Tunnel.

Cue huge jams and a lengthy closure as south-east London’s road network ground to a halt while the difficult task of resurfacing the tunnel began. Three-hour delays for buses were reported at the height of the disruption, while howls of frustration could heard from as far away as the Kent coast.

None of this is good for the lives of people who live near the tunnel. It’s no good for the wider economy, either.

But the proposed Silvertown Tunnel is no solution to Blackwall Tunnel woes – whether huge failures like Tuesday’s, or the minor closures that happen every day.

It fails as a diversionary route – blighting Canning Town and Poplar

As a diversion route, the proposed tunnel is inadequate for the levels of traffic that use Blackwall each day. Normal operation would see it restricted to just one lane for normal traffic, with another set aside for buses and HGVs. At times of disruption, all traffic would be able to use both lanes… only to hit a set of traffic lights at the tunnel’s northern exit.

Many drivers from south London and Kent assume they’ll be able to just fly away from the Silvertown Tunnel once they cross the Thames. That won’t be the case on a good day, and it certainly won’t happen on a bad day. Northbound traffic would emerge at a rebuilt Tidal Basin Roundabout – a junction that’d be controlled by traffic lights.

At Tidal Basin Roundabout, you can head right towards Silvertown and local roads through the Royal Docks; or left to the Lower Lea Crossing and the Docklands. There’d be no direct route for the majority of diverted Blackwall Tunnel traffic to reach the A12 towards Bow – to do that you’d need to proceed through three more congested junctions, all of which are vulnerable to jams on the A13 or on the Limehouse Link/ Aspen Way.

With the Silvertown Tunnel in place, a Blackwall Tunnel closure would be likely to spread traffic jams across both sides of the Thames, grinding Lower Lea Crossing, Leamouth Road and East India Dock Road to a halt.

If you were heading towards Essex, you’d end up on local roads through Silvertown and Beckton which aren’t up to the job of taking all the diverted traffic.

Traffic jams will still blight south-east London – and wreck bus services

Meanwhile, traffic would start queuing back from Tidal Basin Roundabout, through the Silvertown Tunnel, and back down the A102 as before. As usual, buses would take the biggest hit, with route 108 rendered unusable, just as it is now.

And all this is taking TfL’s highly dubious assertions of a minimal traffic increase from the Silvertown Tunnel at face value. New roads have an unfortunate habit of generating new traffic, so the combined Blackwall and Silvertown approach would be significantly busier than it is now.

It’s also worth saying that the location of the Silvertown Tunnel makes it impractical for A12 drivers when the southbound Blackwall Tunnel packs up; you’d either be stuck on the northern approach or crawling through Stratford, West Ham and Canning Town.

River crossings and the roads around them will always be vulnerable to disruption – even the network of bridges in west London suffers badly when one is closed. The Silvertown Tunnel would merely add pressure to existing roads – particularly the A102 – and would be little use when things go wrong with Blackwall.

Cut traffic levels, cut the number of jams

The only way you can guarantee reducing congestion is by reducing the amount of traffic on the roads – and giving Londoners alternative ways to cross the river, such as by public transport, on foot, or by bike. This would free up space for those who need to use the roads.

Now he is mayor, we are calling on Sadiq Khan to commission a thorough review of the Silvertown Tunnel, as he promised, along with the other crossings proposed under his predecessor.

All of us – drivers, residents, and commuters – deserve fresh thinking on this issue, and not the same old “solutions” that are bound to fail, just as the Blackwall Tunnel did on Tuesday.