Forget road bridges. TfL should extend the London Overground to Thamesmead and Abbey Wood

The bustling transport hub that is Thamesmead town centre. Image: Darryl Chamberlain.

Listen carefully to local politicians in the east of London, and there's a low mantra you keep on hearing. A mantra of desperation.

"River crossings... jobs and investment... river crossings... jobs and investment..."

Newham's elected mayor may not be standing in Beckton, staring at Thamesmead with a tear in his eye; and the leader of Bexley Council may not be gazing over at Rainham, wondering what it'd be like to for her to be closer to the marshes there.

But getting between east and south-east London can be a pain, whether by road or rail. The River Thames widens dramatically once you pass Woolwich, and the communities on either side of the water have very little to do with each other.

That simple fact of geography has always been with us as London has grown. But in the recent years, it's been blamed for low employment levels in these riverside communities.

In this narrative, the area's problems have little to do with the decline of established industries – the Royal Arsenal, the docks, the Ford car plant at Dagenham – and the lack of new employment to replace them.

Neither does it have anything to do with London's politicians building a whole new town on the south bank – Thamesmead – with utterly inadequate public transport, leaving much of it more than a mile from a railway station. The nearest its residents get to fast, easy travel are London City Airport-bound jets roaring over their heads.

No, it's just evil geography to blame. Doing nothing is not an option, these politicians declare. But while elsewhere in London, public transport is improved and steps are promised to clean up the air, here, they want to build thumping great roads instead.

New roads would be ridiculed elsewhere

In most of the rest of London, laying down new tarmac would be met with ridicule. The capital is too scarred by memories of the London Motorway Box, which threatened to destroy now-desirable areas such as Hackney, Highbury and West Hampstead.

But south east London is a part of town that’s underneath the key on most maps. It’s always been expected to put up with second best.

Three crossings are proposed. By far the most advanced is the Silvertown Tunnel, four miles west of Thamesmead.

This road between the Greenwich Peninsula and Royal Docks – both already being redeveloped off the back of new public transport – will do little to connect areas that are currently lying dormant. Instead, it's an add-on to the Blackwall Tunnel, aimed at solving congestion there. 

But the plan is fatally flawed. It shares Blackwall’s already-congested southern approach, and is designed to allow HGVs easier access to streets north of the river.

It’s more likely to generate more traffic on its approaches and overwhelm local roads, creating new bottlenecks elsewhere and exacerbating already poor pollution problems.

Don't take my word for it – those are the findings of a report commissioned by Greenwich council. Greenwich dumped the report and supported the tunnel anyway.

But Hackney council recently passed a motion opposing it; Southwark and Lewisham councils have serious doubts about the scheme, too.

The other road crossings are planned to the east and west of Thamesmead – entrenching car dependency in an area the capital’s decision-makers created, then forgot about.

Ease demand by giving Thamesmead the Overground

Congestion is a London-wide problem, not just a parochial issue at a few bottlenecks. The Silvertown Tunnel won't do a thing to solve that. And without a serious effort to cut traffic across the capital, all of these crossings are doomed to failure.

Yet if London's ready to spend £1bn on a river crossing, then we should go easy on the tarmac. One solution would not just help ease demand on Blackwall Tunnel, but also spark interest in London’s neglected new town without putting an extra car on the roads. It's extending the London Overground, from Barking to Thamesmead and Abbey Wood.

The Gospel Oak to Barking line used to be the runt of London's railway litter, with clapped-out diesel trains wheezing their way across north-east London at miserly 45-minute frequencies.

Since 2007, it's been transformed as part of the London Overground network, with four new trains per hour, often full to bursting. Plans are afoot to electrify it and extend it onto Barking Riverside, a huge housing development by the Thames that's been on hold until decent public transport can be arranged.

That sprinkle of Overground magic is set to be the catalyst for 10,000 new homes on the brownfield site.

Yet despite the clamour for ways of making the Thames easier to cross, taking the extension on a couple of miles further, to Abbey Wood, isn’t on the agenda.

The effects would be dramatic. Thamesmead residents would be finally plugged into the London rail network for the first time since the town was founded in 1967, while Barking Riverside residents would gain an interchange with Crossrail at Abbey Wood.

Northbound traffic in the Blackwall Tunnel in the morning rush hour. The red diamonds are the vehicles' origin; blue squares its destination. The proposed Overground extension is shown in yellow. Image: TfL/Darryl Chamberlain.

It could also take pressure off the roads. A hefty chunk of Blackwall Tunnel traffic comes from Thamesmead, from people who end up driving because their current transport options are so poor. The area’s “town centre” is served only by a pair of poorly-placed bus stops.

Politicians are waking up to the idea – but they need to move fast

Why isn’t it happening already? Thamesmead and Abbey Wood are missing out because of short-term thinking at London's City Hall. Just as with the Bakerloo and Northern line extensions, the Barking Riverside extension is intended to regenerate land that has seen little development.

Creating new links to serve existing communities is at the bottom of the priority list. A Thamesmead Overground connection languishes on TfL’s wishlist for the year 2050. If London’s politicians are serious about reviving the community they forgot, they need to be pushing this up the list as soon as they can.

If only. TfL's map of the Overground in 2026, with the Thamesmead extension drawn on in crayons. Image: TfL/Darryl Chamberlain.

Some already are. Barking & Dagenham council leader Darren Rodwell was the first to call for it last year.

A petition from the No to Silvertown Tunnel campaign was followed by action from two Labour assembly members. Fiona Twycross asked if building a new station at Barking Riverside that could quickly become redundant was a waste of money, while Len Duvall suggested that an extension that didn’t cross the river was a missed opportunity.

Only a fool would pretend the puzzle of making it easier to cross the Thames is an easy one to solve. But the people of Barking and Thamesmead deserve the same sustainable solutions that are being proposed elsewhere.

Occasionally, an extension of the Docklands Light Railway is suggested for Thamesmead – usually to make one of the road bridges seem more palatable. Yet an Overground link would dramatically widen opportunities for Thamesmead’s residents to get around the capital compared with the slow and limited options provided by the already-overloaded DLR.

In May, a new mayor will have to decide what to do with Boris Johnson’s transport legacy. Whoever gets the job should ditch the £1bn Silvertown Tunnel – a project that’s doomed to failure. Instead, he or she should start putting the river crossings programme on a sustainable track, and bring the Overground to Thamesmead.

Darryl Chamberlain is a writer and one of the founders of the No To Silvertown Tunnel campaign. He blogs at 853

 
 
 
 

The mountain in North Wales that tried to stop the UK’s blackout

Elidir Fawr, the mountain in question. Image: Jem Collins.

Last Friday, the UK’s National Grid turned to mush. Not the official term perhaps, but an accurate one after nearly one million people were left without power across the country, with hundreds more stranded at train stations – or even on trains (which isn’t nearly as fun as it might immediately sound). 

Traffic lights stopped working, back-up power failed in hospitals, and business secretary Andrea Leadsom launched an investigation into exactly what happened. So far though, the long and short of it is that a gas-fired power station in Bedfordshire failed just before 5 o’clock, followed just two minutes later by Hornsea offshore wind farm. 

However, amid the resulting chaos and inevitable search to find someone to blame for the outage, a set of mountains (yes, mountains) in North Wales were working extremely hard to keep the lights on.

From the outside, Elidir Fawr, doesn’t scream power generation. Sitting across from the slightly better known Mount Snowdon, it actually seems quite passive. After all, it is a mountain, and the last slate quarry in the area closed in 1969.

At a push, you’d probably guess the buildings at the base of the mountain were something to do with the area’s industrial past, mostly thanks to the blasting scars on its side, as I did when I first walked past last Saturday. 

But, buried deep into Elidir Fawr is the ability to generate an astounding 1,728 megawatts of electricity – enough to power 2.5 million homes, more than the entire population of the Liverpool region. And the plant is capable of running for five hours.

Dubbed by locals at the ‘Electric Mountain’, Dinorwig Power Station, is made up of 16km of underground tunnels (complete with their own traffic light system), in an excavation which could easily house St Paul’s Cathedral.

Instead, it’s home to six reversible pumps/turbines which are capable of reaching full capacity in just 16 seconds. Which is probably best, as Londoners would miss the view.

‘A Back-Up Facility for The National Grid’

And, just as it often is, the Electric Mountain was called into action on Friday. A spokesperson for First Hydro Company, which owns the generators at Dinorwig, and the slightly smaller Ffestiniog, both in Snowdonia, confirmed that last Friday they’d been asked to start generating by the National Grid.

But just how does a mountain help to ease the effects of a blackout? Or as it’s more regularly used, when there’s a surge in demand for electricity – most commonly when we all pop the kettle on at half-time during the World Cup, scientifically known as TV pick-up.

The answer lies in the lakes at both the top and bottom of Elidir Fawr. Marchlyn Mawr, at the top of the mountain, houses an incredible 7 million tonnes of water, which can be fed down through the mountain to the lake at the bottom, Llyn Peris, generating electricity as it goes.


“Pumped storage technology enables dynamic response electricity production – ofering a critical back-up facility during periods of mismatched supply and demand on the national grid system,” First Hydro Company explains.

The tech works essentially the same way as conventional hydro power – or if you want to be retro, a spruced up waterwheel. When the plant releases water from the upper reservoir, as well as having gravity on their side (the lakes are half a kilometre apart vertically) the water shafts become smaller and smaller, further ramping up the pressure. 

This, in turn, spins the turbines which are linked to the generators, with valves regulating the water flow. Unlike traditional UK power stations, which can take hours to get to full capacity, at Dinorwig it’s a matter of 16 seconds from a cold start, or as little as five if the plant is on standby.

And, designed with the UK’s 50hz frequency in mind, the generator is also built to shut off quickly and avoid overloading the network. Despite the immense water pressure, the valves are able to close off the supply within just 20 seconds. 

At night, the same thing simply happens in reverse, as low-cost, surplus energy from the grid is used to pump the water back up to where it came from, ready for another day of hectic TV scheduling. Or blackouts, take your pick.

Completed in 1984, the power station was the product of a decade of work, and the largest civil engineering project commissioned at the time – and it remains one of Europe’s largest manmade caverns. Not that you’d know it from the outside. And really, if we’ve learned anything from this, it’s that looks can be deceiving, and that mountains can actually be really damn good at making electricity. 

Jem Collins is a digital journalist and editor whose work focuses on human rights, rural stories and careers. She’s the founder and editor of Journo Resources, and you can also find her tweeting @Jem_Collins.