Your city is making you sick. Diesel fumes are contributing to cancer and alzheimers. Air pollution is causing 40,000 early deaths per year in the UK. And on Tuesday we learned, thanks to new data from Greenpeace, that children are at risk too, with 47,000 babies and children exposed to illegal levels of air pollution at nurseries near polluted roads.

All this has ramped up the pressure on the British government’s new air pollution strategy, to be published this month. It’s a case of third time lucky for the government, whose previous two strategies were thrown out by the High Court for failing to cut emissions soon enough. Theresa May has already indicated that the plan will include some kind of financial help for diesel drivers, possibly in the form of scrappage vouchers in cities where £20-a-day “toxin taxes” are introduced.

In responding to the airborne killers, the air pollution debate to date has focussed, quite narrowly, on getting older diesel vehicles off the road and moving to electric or gas-powered ones. But limiting ourselves to swapping the kind of cars we drive risks missing the bigger opportunity to tackle the myriad other ways cities are making us sick.

Urban ailments

Let’s start with obesity and heart disease. Most British cities encourage a sedentary lifestyle that involves driving to work, sitting at a desk, and driving home again, with many sitting for 9 hours a day. Walking is actually going down as a share of journeys, falling from 28 per cent to 24 per cent over the past 20 years. Cycling is just 2 per cent of journeys; in the Netherlands, it’s 26 per cent.

One of the main reasons cited in surveys as a barrier to walking and cycling is the physical environment. Our many sprawling, cul-de-sac-based estates make walking indirect, and therefore time consuming. Infrastructure is designed for drivers, with pedestrians accommodated on the side and cyclists at best an afterthought. Meanwhile, in the inner-city areas which actually are walkable, a profusion of fried-chicken shops stand ready to mainline fat into our arteries.

Then there’s our mental health. Badly designed streets, buildings and environments don’t just look oppressive: they have a knock-on effect on our wellbeing and ability to cope. People who live in cities have a 40 per cent increased risk of depression, a 20 per cent increased risk of anxiety and double the risk of schizophrenia. We also suffer from a lack of, or poorly designed green space: people living in less ‘green’ areas experience significantly higher levels of mental distress, while gym addicts report lower benefits to wellbeing compared to exercise in natural areas.

As for our social life, all that time spent commuting takes a toll, eating into time spent with family and friends. Things are particularly bad for people on low incomes – one in ten people commuting from outer London deliberately take a longer journey to work, usually by bus, to save money – but taking the bus or coach to work on a journey lasting more than 30 minutes has the biggest negative impact on personal well-being of all commutes.

Churchill is said to have once quipped “never let a good crisis go to waste”. Tackling sickness from air pollution is a prime opportunity to tackle these ills as well and create cities where people can keep active, feel well, and have good home and social lives, as Respublica proposed in our recent report “Air Necessities: Place-based approaches to a pollution crisis”.

Prevention is better than cure

To do so we need to rethink our approach to health, cities, and transport. For one thing, we need to join up transport investment with the creation of dense but green “transit-oriented communities” like Ebbsfleet, where access to transport can be planned-in from the beginning.

Investment in high-quality rapid transit then give existing commuters a good option to switch out of cars. This makes it politically feasible to reduce parking in city-centres, meaning more land available for more productive uses, commercial development and housing. Less parking means less journeys by car, freeing up road lanes to be given over to cycling, housing, or parks, as San Francisco plans to do.

We also need to think about the implications of the way we pay for our city transport. Are zonal tube fares which penalise those in cheaper housing areas and encourage people to cram into the inner zones to save money on travelcards really a good way of organising the city?

In terms of designing cities to be healthier, the NHS’s Healthy New Towns is already showing promise in designing health into housing, but we need to do something for existing towns too. That’s where there’s a lot to be learnt from the “suburban retrofit” movement in the US, whose plans to transform the car-centric suburbs of US metropolises include mixed-use communities in abandoned malls and apartment blocks instead of garage space.

None of this will necessarily come cheap, but there’s a solid rationale for business to get behind healthier cities. Releasing all this valuable land from parking for more efficient uses like housing, creative spaces and businesses increases its productivity – in the long term, paying for itself. And, perhaps, less sick days.

Tom Follett works on devolution policy at the think tank ResPublica.

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