In London, one in seven children has not visited a green space in the last year and many more enjoy that pleasure just once a year. It is a form of environmental inequality with the poorest children most likely to suffer from what has now been dubbed “nature deficit disorder”. Schemes to connect young Londoners to nature are reportedly failing, having reached just 4% of those aged 11 or younger in the capital.

These statistics, and more like them, are forcing environmental campaigners and businesses to ask searching questions about what kind of place London might become in the next three decades. With city populations rising exponentially, what quality of life can its residents expect if they become so disconnected with the natural world?

The solution proposed by geographer and explorer Dan Raven-Ellison is to turn the capital into a new kind of national park, 250 years after the industrial revolution prompted the first wave of national park sites, protecting and celebrating the biodiversity of the city. It is at the forefront of a series of global campaigns on bringing nature back into the city, from the fight for Canada’s Rouge National Urban Park in Toronto to smaller crowd-funded community park projects across the US.

Raven-Ellison’s research indicates that mental health conditions cost London £26m a year, while obesity costs £900m. Our slapdash attitude towards green space not only affects our collective health and wellbeing, draining millions from the public purse, it also fails to make the most of business and tourism opportunities in the garden of London outside the city centre.

A greener, calmer London

His big idea is to designate the capital the Greater London National Park City. This would require little upfront investment and no change in planning legislation. It is essentially a branding exercise in which businesses, public services and individuals all think differently about the way they interact with the urban nature around them. It would, he claims, protect green space, promote tourism and encourage Londoners to spend more time outdoors.

“It’s about improving the health of the city and the people, but it’s also about improving the health of the wildlife as well,” Raven-Ellison says.

So what would being a Londoner in a national park city mean in three decades? How will individual lives look and feel different?

“The first one to three years of a child’s life are the most defining in terms of their health and development and what they’re going to be like in the future,” Raven-Ellison says. “This has a fundamental impact, not only for individuals but also for the city as a whole. We need to be in a park to learn that it’s OK to touch a worm and to interact with nature.” His ambition is to design a city in which it is “socially unacceptable” not to bring young people and the natural world together.

“A national park city could galvanise London enough [to ensure] that 100% of the city’s children have engagement with nature in their first three years,” he adds. In 30 years’ time, those first children of the national park would be graduates, working in business but with a more healthy and more resilient attitude.

Re-thinking business

London’s business sectors might also look fundamentally different, with profitability judged not only in fiscal terms but by the social and environmental impact they have on their local area. Raven-Ellison envisages a future in which economic growth is spread to the outer boroughs of the city and national park city status sparks a boom in eco-businesses. “There are so many business opportunities that can be inspired by this idea. That’s one of the really exciting things about it. There are all kinds of ways it can be spun out.”

With a quarter of today’s London taken up by privately owned gardens – one third of which are paved over, increasing flood risks – a national park city three decades down the line would be home to residents who care about the stewardship of the land.

Raven-Ellison’s campaign has attracted high profile support, from PR agency Weber Shandwick to developer Sir Terry Farrell. So far, however, London’s politicians have failed to embrace the challenge to think differently about the capital. That’s something campaigners also want to change.

Matthew Frith, director of policy, London Wildlife Trust, and a member of the steering group for the national park city, said the city needs to change the way it thinks about its development.

“A lot of what [has been] done was done on the basis that England is going through some kind of social and economic decline. That’s now very different, and London is changing so rapidly with an anticipated population of 10 million by 2030,” he said. “We have got a greater desire for London to be a global powerhouse. But what does that mean? That causes us a great deal of trepidation.”

He likens the idea to the slow food movement. “It’s turning the idea of the city on its head, which is very appealing,” Frith says. “There is a tension between living in a city and what the city has to offer. The city is a hard place to live and I believe it’s getting harder. It’s about trying to slow down and getting people to recognise the ecological footprint of their behaviour. It’s about a celebration of the city and its fantastic green benefits.”

So for him what might the park achieve in 30 years’ time? “That London becomes a slower place to live.”

Kate Henderson, chief executive of the Town and Country Planning Association, believes an urban national park could follow in footsteps of the first garden cities in the 1890s, when a fruit tree was planted in every garden, “so you can grow some of your own local produce. That was something that was planted in. I think there is a huge amount to learn about how we plan places and how they’re used”.

The scheme is taking tentative steps forward. City Hall has thrown some weight behind the campaign. A senior adviser on environment and energy to the Greater London Authority has written to Raven-Ellison agreeing to “allocate some officer time” to support the campaign’s research. “The ideas and proposals that might be generated would no doubt be helpful,” it concludes. “We are interested to hear more about how the principle of establishing an entity based on a national park objectives could be transposed into a workable structure for London.”

The campaign’s full strategy will be published this Summer but a public consultation with London citizens and businesses is open until next month.

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