Do British cities have grid systems? We used science to find out

Some American cities with grid systems, yesterday. Image: Google Maps.

Grids! What are they good for? Basic urban planning, it turns out: take a look at how a US city is laid on a map, and often you’ll be looking at a grid of streets criss-crossing at exactly 90 degrees.

This is not strictly speaking an American phenomenon – similar systems have been used across the world for thousands of years because, well, it’s an easy way to divide up land. Fans of Worthing in West Sussex may be excited to learn that it owes some of its street layout to ‘centuriation’ – the grid system used by the Roman Empire.

But the US has really taken the idea and run with it, as you can see from these charts, which show the most common road orientations within a given city – the closer the chart is to a cross over the centre, the more closely aligned the city is to a grid. Just look at how dead on most of them are:

The street orientations of 25 US cities. Image: Geoff Boeing.

These charts are the work of urban planning researcher Geoff Boeing, who’s put together some software that can analyse the layout of the roads within a city, or any other geographical space, using data from OpenStreet Maps.

 

The streets of Manhattan, in map and polar histogram form. Image: Geoff Boeing.

Here he’s used the same process on 25 cities from around the world, which tend to be a lot less carefully laid out:

Image: Geoff Boeing.

Even where there isn’t a strict grid system, you can still usually make out an overall orientation if you squint – look at London, for instance.

London with some highly scientific lines drawn on it. Image: author’s own work.

When the City of London burned down in the great fire, the suggestions for how to rebuild it actually included various ideas for grid systems. It came to nothing, and the city ended up with broadly the same layout it had before it burned down – but if we use Boeing’s method, we can there is a pattern to the street orientation:

The City of London as a histogram. Image: author’s own work.

Which does make sense when you think about it – the roads either tend to follow the line of, or run down to, the river, thus: a grid.

Here’s the City together with the London boroughs:

The London boroughs as polar histograms of street orientation. Maps are so last year! Image: author’s own work.

What this doesn’t account for is size. Perhaps the larger the borough, the less likely it is to have a clear pattern – whether that be because it has several ‘competing’ grids or just is not going to be tied down with geometry, man. If we compare the City (1.12 square miles) and Bromley, the largest London borough (57.97 square miles), that seems plausible.

But that’s not necessarily true, because here are the boroughs in size order:

The London boroughs, now in size order. Image: author’s own work.

Lambeth is noticeably more of a jumble than its ‘size-neighbours’ Southwark and Camden, for instance.

And for that one guy who complains on Facebook that I only ever write about London, here are 25 UK towns and cities:

London plus 24 other weird places that aren’t London. Image: author’s own work.

But what about the most famous grid system in the UK, in Milton Keynes? Well, erm:

The Milton Keynes ‘grid system’. Image: author’s own work.

So does Milton Keynes have a grid system or not? Well, yes, but isn’t that strict.

Firstly, that’s because not every road is part of the grid – the ‘squares’ of the grid are the main roads and the smaller roads within don’t necessarily conform to any particular layout. And secondly, because it was deliberately designed not be as rigid as an American-style grid. In the words of David Lock, a planner who’s worked in Milton Keynes since the 1970s:

“The designers decided that the grid concept should apply but should be a lazy grid following the flow of land, its valleys, its ebbs and flows. That would be nicer to look at, more economical and efficient to build, and would sit more beautifully as a landscape intervention.”

Don’t worry though, grid fans, they did stick to a proper grid for the town centre.

Grids! Grids! Grids! Image: author’s own work.

Right, now for a rousing singalong of that classic post-war planning anthem: “You’ve never seen anything like it: Central Milton Keynes!”

Altogether now:

Ed Jefferson works for the internet and tweets as @edjeff.

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Barcelona’s car-free “superblocks” could extend lives. So will they catch on elsewhere?

Barcelona. Image: Getty.

The world’s biggest cities have larger populations and higher economic outputs than some countries. But as they grow in size and complexity, cities are also facing thorny challenges that threaten the health and happiness of residents. Congestion, pollution and a lack of community spaces have become major drags on people’s aspirations and experiences of urban living.

In response, cities must manage their resources and priorities to create sustainable places for visitors and residents, and foster innovation and growth. Enter Barcelona – the capital of Catalonia, in Spain – where a bold stroke of urban planning first introduced “superblocks” in 2016.

Image: ISGlobal/FAL.

Superblocks are neighbourhoods of nine blocks, where traffic is restricted to major roads around the outside, opening up entire groups of streets to pedestrians and cyclists. The aim is to reduce pollution from vehicles, and give residents much-needed relief from noise pollution. They are designed to create more open space for citizens to meet, talk and do activities.


Health and well-being boost

There are currently only six superblocks in operation, including the first, most prominent one in Eixample. Reports suggest that – despite some early push back – the change has been broadly welcomed by residents, and the long-term benefits could be considerable.

A recent study carried out by the Barcelona Institute for Global Health estimates that if, as planned, 503 potential superblocks are realised across the city, journeys by private vehicle would fall by 230,000 a week, as people switch to public transport, walking or cycling.

The research suggests this would significantly improve air quality and noise levels on the car-free streets: ambient levels of nitrogen dioxide (NO₂) would be reduced by a quarter, bringing levels in line with recommendations from the World Health Organisation (WHO).

The plan is also expected to generate significant health benefits for residents. The study estimates that as many as 667 premature deaths from air pollution, noise and heat could be prevented each year. More green spaces will encourage people to get outdoors and lead a more active lifestyle.

This, in turn, helps to reduce obesity and diabetes and ease pressure on health services. The researchers claim that residents of Barcelona could expect to live an extra 200 days thanks to the cumulative health benefits, if the idea is rolled out across the city.

Space to play. Imag: Mosa Moseneke/Unsplash.

There are expected to be benefits to mental health, as well as physical health. Having access to such spaces can stave off loneliness and isolation – especially among elderly residents – as communities form stronger bonds and become more resilient.

Stumbling blocks

It was Salvador Rueda, director of the Urban Ecology Agency of Barcelona, who first championed the introduction of superblocks – and he argues that the idea could be used in any city. Even so, authorities looking to expand the concept in Barcelona or beyond will need to be mindful of some concerns.

Changes like these require capital investment. Even as the car-free streets are transformed with urban furniture and greenery, the remaining major roads will likely have to accommodate heavier traffic.

Nothing comes for free. Image: Zvileve/Flickr/creative commons.

Further investments in local infrastructure – such as improving surrounding roads to deal with more traffic, or installing smart traffic management system – could be required to prevent serious congestion. Then the question remains, how to finance such investments – a higher tax rate is unlikely to be popular.


What’s more, whenever a location becomes more desirable, it leads to an increase in property demand. Higher prices and rent could create pockets of unaffordable neighbourhoods. This may lead to use of properties for investment purposes and possibly, displacement of local residents.

It’s also worth noting that Barcelona is an old and relatively well-planned European city. Different challenges exist in emerging global cities across Asia, Africa and Latin America – and in younger cities in the US and Australia. There is a great deal of variation in scale, population density, urban shape and form, development patterns and institutional frameworks across the cities. Several large cities in the developing world are heavily congested with uncontrolled, unregulated developments and weak regulatory frameworks.

Replicating what’s been done in Barcelona may prove difficult in such places, and will require much greater transformations. But it’s true that the basic principles of superblocks – that value pedestrians, cyclists and high quality public spaces over motor vehicles – can be applied in any city, with some adjustments.

Leading the way

Over the history of human civilisation, great cities have been at the forefront of innovation and social progress. But cities need a robust structure of governance, which is transparent and accountable, to ensure a fair and efficient use of resources. Imposing innovation from the top down, without consultations and buy-in, can go squarely against the idea of free market capitalism, which has been a predominant force for modern economies and can lead push-back from citizens and local businesses.

Citizens must also be willing to change their perspectives and behaviour, to make such initiatives work. This means that “solutions” to urban living like superblocks need to have buy-in from citizens, through continuous engagement with local government officials.

A man speaks at a public consultation on the Eixample superblock in Barcelona. Image: Ajuntament Barcelona/Flickr/creative commons.

Successful urban planning also needs strong leadership with a clear and consistent vision of the future, and a roadmap of how that vision can be delivered. The vision should be co-developed with the citizens and all other stakeholders such as local businesses, private and public organisations. This can ensure that everybody shares ownership and takes responsibility for the success of local initiatives.

There is little doubt that the principles and objectives of superblocks are sound. The idea has the potential to catch on around the world – though it will likely take a unique and specific form in every city.

The Conversation

Anupam Nanda, Professor of Urban Economics and Real Estate, University of Reading.

This article is republished from The Conversation under a Creative Commons license. Read the original article.