Programme Updates

The answer to our cities’ air problems—tech, nudge, or big stick?

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Air pollution has improved since the Great Smog, but it still causes more deaths than car accidents in London, and globally the problem is still worse. What combination of policy and practice will keep people moving—and breathing? The article below is based on a roundtable discussion, convened by Go-Ahead Group CEO David Brown and Jericho Chambers on 5 October 2017.

It’s now 65 years since the Great Smog of London descended on the city’s inhabitants on Friday December 5, 1952. The pea-soupy yellow and black murk—caused by the combination of cold weather, windless conditions and an anti-cyclone—lasted four days.

A man guiding a London bus through thick fog with a flaming torch. Source

From domestic coal fires in homes, plus huge coal-fired power stations at Fulham, Battersea, Bankside, Greenwich and Kingston-Upon-Thames, every day the Smog lingered, with 1,000 tonnes of smoke particles, 140 tonnes of hydrochloric acid, 14 tonnes of fluorine compounds, and 370 tonnes of sulphur dioxide were pumped into the air. And stayed there, a 200-feet deep blanket covering what was then the world’s largest city.

‘You had this swirling,’ recalled Stan Cribb of T Cribb and Sons, an East End funeral director, ‘as if somebody had set a load of car tires on fire. It’s like you were blind.’ Visibility was so low that London Transport inspectors had to lead buses out of terminuses with flares. Four thousand people lost their lives from the Great Smog’s effects.

The quality of the air in London—and all other cities in the UK—is now far superior to those days. The Clean Air Act of 1956 saw to that. But air quality is back on the agenda. Fast forward and here’s a Guardian headline from October 2017: Revealed: every Londoner breathing dangerous levels of toxic air particles.’

This is not just a London problem, although the capital typically hogs much of the Unclean Air limelight. And the problem is not simply down to the size of each metropolis. The city of Manchester has better air quality than Nottingham, Leicester and Luton—all of which are much smaller cities.

So what is to be done?

Go-Ahead Group and Jericho Chambers recently convened an expert panel on the subject of how to Breathe Air Into The Congested City. The panel included representatives from Department for Transport, GLA, TfL, European Transport Research Advisory, Zipcar, Arup, Go-Ahead Group and others. (Full attendee list at the bottom). The discussion was conducted under the Chatham House Rule which helped the civil servants present express themselves freely. The podcast below gives an account of a separate series of interviews conducted as part of the discussion, drawing out thinking on current challenges and solutions from some of the leading players in the transport space. Either stream or download. 



Many British cities are running out of road. In the capital, for example, Transport For London thinks that in around four years it will have exhausted all existing technological means and tricks of keeping traffic moving through congested streets. London remains the most congested UK city followed by Manchester, Aberdeen and Birmingham. And congestion fouls the air.

It is now 13 years since the introduction of a Congestion Charge in central London. In 2003—the first year of charging—the average speed for all vehicles was 10.9 mph, up from 8.8 mph the previous. City planners took heart. But in 2015 that figure had fallen to 8.3 mph.  

Huge construction projects both above and below the ground have slowed traffic by removing road space for vehicles. Many road junctions have been deliberately redesigned to make them more friendly to those on bikes or on foot while making them markedly less efficient at processing large numbers of vehicles. The large-scale removal of traffic gyratory systems slows speeds around hubs where trunk roads come together.

David Brown: Cities will have to work out how to prioritise.

David Brown, the CEO of Go-Ahead Group accepts that the status quo won’t do. As the operator of buses from Plymouth to Gateshead he needs to keep his buses moving. ‘Cities cannot just grind to a halt amid toxic air,’ he says. ‘Road space is scarce and finite. Cities will have to work out how to prioritise. There will be times when the public good outweighs some people’s desire for unlimited journeys, and one-hour deliveries to the door.  How do we have this honest conversation, and how do we trade off public transport, freight, walking, cycling, cars and public space?  Is this the time for road pricing? We need leadership and private and public sectors working in partnership.’

That leadership is likely to come from political sources. The advent of the City mayors across the UK has devolved power from the centre giving increased powers to make critical transport decisions on their own. Some have made more of this power than others.

Isabel Dedring: We should embrace rather than reject politics.

‘In the infrastructure industry, people often like to vilify politics as a cause of delay and uncertainty. However, in my experience politics are more often than not the reason for improvement and change in policy (for example action on air quality and cycling in London) and in catalysing infrastructure projects (for example the Overground extension to Barking Riverside, the extension of the Bakerloo Line). So we should embrace rather than reject politics,’ says Isabel Dedring, once a London deputy mayor responsible for transport, now at global engineering consultants Arup.

Dedring also highlights the need for more comprehensive, fact-based analysis in policy making. ‘It always amazes me the extent to which policy is made by anecdote. There is too much mythology—often combined with an innate conservatism. Cities need to be scientific about their decision-making, and be bold with it.’

While the public/private boundaries in city transport are blurring, politicians are in a unique position to consider the Big Picture and manoeuvre public good to gain precedence over individual’s desires. There are three ways to bring about change in city transport systems and thus improve air quality. The increased use of technology to make things more efficient, persuasion or nudging of individuals to make them behave differently or the big stick of legislation/rule changing which includes charging for road access.   

The advances in digital technology plus GPS mean that road-pricing—always a highly sensitive subject—is now far more practicable than a decade ago.

A number of roundtable members think [road-pricing] to replace existing transport taxes for fuel and vehicles is now inevitable in due course. You will drive your miles and you pay your price accordingly.

The cost of driving in cities would be higher—in some cases much higher—than driving on motorways or other rural roads. But this, it was acknowledged, is a hard political sell.

Centre for London’s Ben Rogers with Elliot Treharne of the GLA. Practicable solutions to air pollution encompass policy, planning, technology and public initiatives.

There is also the influence of unexpected events. It is only two years since the first revelations of the VW scandal. But diesel’s fall from grace has been precipitate. From wearing an early Noughties eco halo due to its lower CO2 emissions than petrol, diesel has become the bad boy fuel. If people did not know about the ill effects created by nitrogen dioxide and microscopic soot particles before VW started trying to mask them they certainly do now.

Ten years ago environmental activism centred around global issues such as CO2 but this has now been supplemented by a far greater focus on local issues such as smog and particulates. This month (October 2017) a higher T-charge will be applied to older, more polluting diesel vehicles entering central London. It is no coincidence that London’s mayor Sadiq Khan was diagnosed with asthma a few years back.

There was some unease from some panel members that modern EU 6 diesels have reached emissions standards that fail to get the clean credit they deserve. Nevertheless, with cities like Paris taking the lead in banning diesel engines from 2020, and with Oxford banning all but electric, non-emitting vehicles from the city centre starting in the same year, it was generally agreed that diesel’s days are now numbered. The Oxford authorities are the first to produce comprehensive plans for improving air quality since the government announced in July that 29 towns and cities would need to address illegal levels of pollution. All will have to produce draft proposals by the end of March and a final plan by December next year to achieve compliance in the “shortest possible time”. Battery technology, which has promised so such for so long, was finally making serious strides forward even for large vehicles such as buses.

One thing is for certain, while 71% of Londoners now never drive in the central parts of the capital, cities are now filled with delivery vehicles, the result of the profound digital shift away from shopping in person in bricks-and-mortar shops to shopping online. These parcels containing books, clothing, and shower rails all have to be delivered—often to people’s place of work. And it’s not just non-perishables from Amazon—food is now on the move all over cities 24 hours a day in cars, on bikes and on mopeds.

Several panel members thought that charging extra fees within cities for freight carriage was now a ‘no brainer’ because the current barriers to entry were far too low and that higher costs would bring consolidation and therefore greater efficiency.  It simply isn’t sustainable for thousands of 90% empty white delivery vans to be clogging city roads and parking on double yellow lines as they offload their parcels.  Whether Amazon customers would continue to be able to receive delivery of purchased goods within hours was questioned by several. And drones do not appear to be the answer. Most are highly sceptical that they will ever take off in city centres, certainly as long as UK aviation rules state that any flying delivery device must be at least 150 metres from a building and 50 metres from a person or vehicle. Aerial cameras also create great unease among privacy and civil liberties campaigners.

Some research suggests up to 30% of traffic in cities is wandering around in search of a parking space.

What may seem to many a mundane subject—parking—is critical. Companies such as Zipcar, the car-sharing business, decry the fact that private vehicles spend so much of their lives stationary but taking up road space while they are parked. Hence the enthusiasm for car-sharing and maximising their use. Several manufacturers, including BMW’s ‘DriveNow’ and Mercedes’ ‘car2go’ are moving into the sharing market which will have profound implications for their premium brand status. Fewer and fewer city-based Milennials own cars – if they can share flats via AirBnB then cars follow easily. A number of people at the roundtable were quite blunt about a reduction in car ownership being a positive step forward. 

Nick Lester-Davis: It’s easy to think of roads and streets just as places of movement, but these are also places where people live, do their shopping, play.

‘I was in rural Ludlow recently,’ said Nick Lester-Davis. ‘We came by car and it took me 20 minutes to find a parking space. Parking charges are far too low almost everywhere. Some research suggests up to 30% of traffic in cities is wandering around in search of a parking space.’

But parking has its supporters. It’s not just a cash-generator for hard-up local authorities but critical for bringing customers to hard-pressed bricks-and-mortar retail outlets in towns and cities. Towns compete hard against each other for citizen’s business and if car parks and roadside spots aren’t priced keenly then customers go elsewhere.  

There has been much talk in recent years about the development of autonomous vehicles (AVs). While they may well have a place on the wide cross-state highways in the United States, their suitability for cities is far less clear. Negotiating their way down city streets filled with roadworks and pedestrians—who when they step in front of an AV force it to brake immediately—is not going to be easy.

At the same time Professor Frank Kelly, Professor of Environmental Health at King’s College London, warned that it’s not just vehicle tailpipes which create emissions. Brakes and tyres, previously ignored when it came to emission-measurement, are now becoming the focus of new research. Given every vehicle requires brakes and tyres, again reducing the number of vehicles on the roads appears to be a key part of the solution.

There’s a strong sense that what cities require now is a Big Fix. There was talk of the search for ‘an Oyster Card of the 2020s’. Do we, for example, require a new Clean Air Act for the 21st century? Far more work needs to be done to make intelligence about the fastest ways to move about cities via public transport instantly accessible. Citymapper is leading the way here in providing real time data on where the pinch points lie.  A major concern remains that elected politicians are not moving sufficiently quickly because big, bold ideas are fraught with political risk. One way or the other, however, the writing appears to be on the wall for private cars with single occupants in city centres in the next two decades. ‘It’s all very well hearing from the cycling and walking camps who are highly proficient lobbyists. A few more policymakers should spend a bit more time travelling by bus,’ remarked one expert.  

‘What cities will have to assert for public highways in future is that the public can access but on our terms,’ said another panel member. One thing is for sure—the path to virtue and cleaner air is not a simple one-way street.

Incidentally, the World Health Organization gathers average particulate levels from cities around the world. They suggest that Beijing’s levels are about five times worse than London’s. The cities with the dirtiest air are Zabol in Iran and Onitsha in Nigeria. All three know real smog when they see and breath it.


The roundtable was convened by Go-Ahead Group, and chaired by Go-Ahead Group CEO, David Brown. Go-Ahead is a leading international transport provider. The Group is responsible for more than a billion journeys each year in the UK and beyond, and is the largest operator of bus services in London. 

Matthew Gwyther is a journalist and commentator. He edited Management Today for fifteen years and is also the main commentator on BBC Radio 4’s In Business programme. His work appears in The Independent, The Telegraph, The Observer and GQ, among others.


Roundtable members include:

David Brown, CEO, Go-Ahead Group (Chair)

Christine Armstrong, Co-Founder, Jericho Chambers
Alexandra Brill, Manager, SustainAbility
Richard Bruce, Director of Energy, Technology & Innovation, Department for Transport
John Dales, Chair of Transport Planning Society, Trustee of Living Streets
Isabel Dedring, former Deputy Mayor for Transport in London and Global Transport Leader, ARUP
Jonathan Hampson, General Manager, Zipcar UK
Martin Harris, Managing Director for Brighton, Go-Ahead Group
Professor Frank Kelly, Professor of Environmental Health, Kings College London
Nick Lester-Davis, Vice-Chair, European Road Transport Research Advisory
Robert Phillips, Co-Founder, Jericho Chambers
Ben Plowden, Director, Strategy and Planning, Transport for London
Ben Rogers, Director, Centre for London
Katy Taylor, Group Commercial and Customer Director, Go-Ahead Group
Elliot Treharne, Air Quality Manager, GLA

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