Analysing the evolution of urban space distribution


Amongst the urban cyclists community, Copenhagen is nowadays considered as the world’s capital of bicycle. The Danish city is even more bicycle-friendly than Amsterdam !

Copenhagenize design co. is a company that aims to, as its name points out, copenhagenize cities. This means to make them more cyclable, by promoting innovative urban design.

The purpose of my article is not to promote this company, even though I am a fervent urban cyclist, but it is to talk about a mapping method seen on the Copenhagenize blog, which inspired me for a map I made on QGIS.

 

The idea

In his article on the blog, Mikael Colville-Andersen, the CEO of Copenhagenize, exposes a method to analyse the distribution of public space between different user categories : pedestrians, cyclists, and cars.

His method consists in analysing an aerial picture. During a family trip in Paris, he took a picture of the intersection of Quai Branly and Pont d’Iéna from the top of the Eiffel tower. He squared off the photo with roughly one square metre squares. He then coloured the squares depending on who the space is intended for (blue for pedestrians, red for cars etc…).

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Analyse of urban space distribution down the Eiffel tower (Source : Mikael Colville-Andersen)

However this method is a bit « home-made », it is very visual and self explanatory.

To our big surprise (really?), we discover that more space is allocated for Almighty Cars than for other user categories.

In the following image, Mikael Colville-Andersen then points out that there are a lot more pedestrians than cars on this intersection, to show how the injustice is even bigger. Space is not distributed logically between user categories.

Urban space distribution and number of users (Source : Mikael Colville-Andersen)

Urban space distribution and number of users per category (Source : Mikael Colville-Andersen)

 

Why so much space for cars ?

As this diagram shows, Parisians walk and use public transportation a lot. Parisians use cars and motorbikes for only 13% of their travels.

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How Parisians move in the city (Source : Le bilan des déplacements en 2014 à Paris)

(You can find this document here.)

This is also true at the scale of the whole Île-de-France region : only 45,3% of travels involve a car or a motorbike.

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How people move in Île-de-France (Source : Commissariat général au développement durable – Service de l’observation et des statistiques)

(You can find this document here.)

But in our car-centric society, cars arrogantly get the biggest slice of the cake. Even though more travels are made by foot or public transportation than by car, more public space is allocated to cars, for driving and parking. This is what  the author calls « the arrogance of space ».

The following quotation describes the opinion of Mikael Colville-Andersen on public space distribution :

« When you actually count the number of individuals using the space the injustice becomes more and more apparent. The Arrogance morphs into pure mocking of the majority of citizens and visitors to the city. Pedestrians clustered together at crossings waiting for The Matrix to reluctantly grant permission to cross. Bicycles thrown to the hyenas into the middle of the Red Desert. »

The author then applies his method to Calgary and Tokyo, to show that the situation can be different in other cities, and that solutions can be found, to make cities less car-centric and more liveable.

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In Tokyo, the famous intersection of Shibuya shows a bigger amount of space allocated to pedestrians, compared to Paris. (Source : Mikael Colville-Andersen)

 

Case study : Porte d’Orléans

I found this method very interesting, not only to describe the distribution of space, but also to study its evolution. I decided to improve this method with GIS and to apply it to the study of the evolution of the space distribution at the Porte d’Orléans intersection, before and after the construction of the tramway T3a, in the south of Paris.

I georeferenced two aerial views on QGIS thanks to the Openlayer plugin. One from May 2004, before the construction of the tramway, and one of October 2007, after the construction.

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Aerial views of the Porte d’Orléans intersection, before and after the tramway construction (Source : Guillaume Lequy, Google images georeferenced on QGIS with the Openlayers plugin)

The next step was to create polygons, according to the user categories. After that I could easily create a categorised symbology so the different categories would appear in different colours.

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Analyse of the evolution of the space distribution between the different user categories at the Porte d’Orléans intersection, before and after the construction of the T3a tramway (Source : Guillaume Lequy)

 

Coordinate system problem…

The last step was to calculate the surfaces of the polygons and to analyse the evolution of space distribution. This is where I spotted a mistake…

The coordinate system of my project is WGS 84 / Pseudo Mercator (EPSG:3857), which is the system of Google maps. When I created the polygon shapefiles, I choose a wrong coordinate system WGS 84 (EPSG:4326). The result is that the surfaces calculated are not in m² and it is impossible to calculate surfaces in m².

As I already spent too much time on this article, I decided to analyse the space distribution using theoric surface units. So let’s say the surfaces are calculated in unit², or u². The units are wrong, but the proportions are still correct.

 

Analyse of the space distribution

We can see that the surface allocated to cars decreased, in favor of public transportation and pedestrians and that a cycle path was created. Also the amount of « lost space » has decreased, which shows a smarter use of urban space. It is also visible that the buildings « moved ». This is because of the picture’s different angles.

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Analyse of the evolution of space distribution at Porte d’Orléans (Source : Guillaume Lequy)

Since 2007, the space distribution has evolved again. Bus lanes were created on the 25 août 1944 square, in the south of the intersection.

Those changes in public space distribution are a general trend in Paris, and in many cities. Urban planners now slowly start to understand that it is important to reduce the place of cars in cities if we want to make the cities more liveable.

 

To go further : you can read this article.


Sources :

http://www.copenhagenize.com/2014/09/the-arrogance-of-space-paris-calgary.html

http://www.copenhagenize.com/2013/03/the-arrogance-of-space.html

https://api-site.paris.fr/images/77965

http://www.statistiques.developpement-durable.gouv.fr/fileadmin/documents/_shared/pdf/IDF_cle0ec212.pdf