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Sadiq Khan’s Pollution Paradox: On the Silvertown Tunnel, and When Rhetoric Doesn’t Match Action

Kids in one of London’s poorest boroughs, Newham, are struggling to breathe. So why is the London Mayor pushing ahead with a new road tunnel that could make the situation even worse?

Sadiq Khan the Mayor of London on stage at the Hay Festival at the weekend, talking about his book Breathe – Tackling the Climate Emergency. Photo: Steven May / Alamy Live News

Sadiq Khan’s Pollution Paradox: On the Silvertown Tunnel, and When Rhetoric Doesn’t Match Action

Kids in one of London’s poorest boroughs, Newham, are struggling to breathe. So why is the London Mayor pushing ahead with a new road tunnel that could make the situation even worse?

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The PR machine surrounding Mayor Sadiq Khan’s new book, ‘Breathe’, billed as a guide to combating the climate emergency, has been firing on all cylinders. Multiple media outlets have dedicated airtime to interviews with Khan, discussing the climate crisis and the solutions proposed in his book. 

It has laudable aims, and the Mayor’s persistence in facing down critics of his soon-to-be-expanded Ultra Low Emissions Zone is to be welcomed. And yet.

Amid the media blitz, a significant detail has been overlooked. Not a single interviewer has challenged the London Mayor on his support for a project that risks worsening air pollution in one of the most polluted areas of the whole UK. 

Despite the climate-conscious rhetoric, a closer examination of Khan’s track record reveals a considerable gap between his words and actions. Campaign group Stop the Silvertown Tunnel goes further: “The London mayor’s decisions may have contributed more to the UK’s CO2 emissions than nearly any other individual in the country.”

‘Breathe’ purports to be a guide to collective action on climate issues. Yet Khan’s response to the outcry over the Silvertown Tunnel from climate, traffic, air quality experts, doctors, residents, and his own party members paints a starkly different picture of his commitment to collective action.

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Two decisions by Khan highlight this inconsistency. In 2016, Mayor Khan greenlit an expansion of London City Airport, resulting in up to 41,000 additional short haul flights per year, increasing CO2 emissions by 600-800,000 tons annually. This move was even denied by Boris Johnson during his tenure. Now that the decision is irreversible, Khan, in a largely performative act, opposes the very increase he enabled.

But Khan’s most significant financial decision as Mayor – remember that the Elizabeth Line was approved under previous administrations – was to approve the £2.2bn Silvertown road tunnel. Labelled as the country’s biggest under-construction road project and the second-largest transport infrastructure project after HS2, Silvertown looks set to increase London’s transport CO2 emissions.

Tunnel Vision

It is time to raise a flagship infrastructure project of Sadiq Khan as Mayor – the Silvertown Tunnel, due to be completed in 2025. While Sadiq Khan has generally been reluctant to discuss it, critics argue it will exacerbate air pollution in London’s most vulnerable boroughs and increase CO2 emissions. This fact has been largely omitted from public discourse, with only one or two notable exceptions. 

Contrary to Khan’s claims, Transport for London’s (TfL) Carbon and Energy Statement clearly shows that Silvertown will increase London’s operational transport CO2 emissions. But TfL’s public estimate underestimates the true increase in emissions by incorporating potential future CO2 reductions from tolls on adjacent roads, thereby glossing over Silvertown’s actual emissions increase. 

There is, sadly, little certainty that extra tolls will be kept under a new mayor. And judging by the Conservative mayoral wannabes’ rhetoric, they do not take kindly to road charging. £55m a year in toll income is a drop in the ocean of the Greater London Authority’s £19bn a year budget. 

Surprisingly, even the Mayor himself appears uncertain about the actual increase in pollution and CO2 emissions the tunnel would generate. Calls for transparency on the figures have been met with refusal from the Mayor, who claims there is a legal obligation for the Blackwall Tunnel toll – a claim that, opponents say, has been debunked. 

Analysis of the Development Consent Order (DCO), the legally binding document governing the project, reveals that a new Mayor would have the authority to rewrite the entire charging policy for Silvertown in line with their priorities, following consultation. There is no explicit requirement within the DCO that a toll must be implemented, nor any specific environmental outcomes to be achieved. 

Lib Dem Assembly Member and anti-pollution campaigner Hina Bokhari tells Byline Times: “For years the Silvertown Tunnel was Sadiq Khan’s dirty secret. Now, Londoners are increasingly aware of just how catastrophic this project is for the environment.”


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Peril of Particulates

A letter from former Commissioner Andy Byford letter to Assembly Member Caroline Pidgeon affirms that without a toll, traffic and pollution will increase, thereby implying a rise in CO2 emissions. 

It is highly likely that the opening of the tunnel will lead to significant increases in particulate matter (PM) emissions in certain areas. While electric vehicles are far less polluting in areas like NO2, they do not produce less particulate matter, which can devastate the lungs. A new tunnel is not likely to result in traffic coming down significantly. Recent research indicates the adverse effects of PM emissions on health, particularly affecting the developing lungs and brains of children.

Even with tolls in place, the Silvertown Tunnel will redirect an additional 20,000 to 30,000 vehicles per day into the East London borough of Newham, with a substantial proportion expected to be highly polluting HGVs. Current levels of PM pollution near major roads in Newham already significantly exceed the Mayor’s 2030 targets for PM2.5 concentrations. Children’s lungs in the borough are literally stunted due to the high levels of pollution – including particulates. 

While Khan denounces climate ‘deniers and delayers’, his endorsement of high-CO2-emitting projects represents another form of climate denial – the refusal to accept the damaging impact of his own projects. That view has only been confirmed when the Mayor has repeated palpably inaccurate statements about the project.

Breathe, tackling the climate emergency by Sadiq Khan goes on sale. Credit: JOHNNY ARMSTEAD/Alamy Live News

Choices to be Made 

As one of the UK’s most vocal politicians on climate matters, Khan has a duty to ensure his actions match his rhetoric. His climate-related decisions draw attention away from the realities of his environmental record. With Labour presenting itself as a government-in-waiting, the public should be aware that Ed Miliband, Shadow Secretary for Climate and Net Zero, endorses Khan despite these concerning actions.

There were choices to be made. Sadiq Khan has reduced congestion charge hours in the centre of London. He cancelled plans for a bike and pedestrian bridge, and later for the ferry that was supposed to supplant it. And plans for an extension of the Bakerloo line have been put on ice due to “lack of funds.” .

So the £2.2bn spent on Silvertown looks increasingly like a missed opportunity to reduce CO2 emissions by funding projects that could decrease emissions. This may feel a little bit like spilled milk – much of the tunnel has already been dug. But it’s important to raise any discordance between rhetoric and action in dealing with the climate emergency. Leaders’ actions should be consistent with their commitments – whatever party they are from.

Khan is right: the consequences of climate inaction are too grave to be ignored. This is especially important when it comes to scrutinising figures in power. With his extensive publicity and media coverage, the London Mayor holds considerable influence over the public’s understanding of climate change and the needed action. A big part of this leadership role should involve living the change you promote, ensuring that the steps taken match the messages conveyed.

The Green Party’s former mayoral candidate Sian Berry tells me Mayor Khan’s book is “trying in vain to minimise the impact of the Silvertown Road Tunnel and minimise the opposition to it.” She has published a range of alternative uses for the tunnel – including letting Londoners walk and cycle through it.

While ‘Breathe’ holds promise as a guide to collective action, all Londoners should question if its author truly embodies that spirit. By failing to listen to expert advice on the Silvertown Tunnel, by advocating for projects that increase rather than decrease emissions, Khan’s record is, unfortunately, rife with contradiction. 

When Labour, as the party likely to form the next government, portrays itself as the protector of climate action, they need to be able to say it with confidence. 

‘Breathe’ is an important work. But, as Hina Bokhari tells me, it is a re-election tool. Journalists and voters need to use their own tools to dig beneath the surface.

City Hall and Transport for London were contacted for comment.

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