Street-network Sprawl in Luján, Argentina

What is Street-network sprawl?

Street-network Sprawl is a way to measure urban sprawl, worldwide, through the connectedness of the streets. Less sprawl means more connected, more walkable streets. Well-connected streets – like New York City’s grid – are more walkable and can be served by public transit.

The street network is permanent, and its connectivity affects the livability and environmental footprint of cities for decades and centuries to come. In places with more connected streets, residents drive less and walk more. A well-connected street network is associated with better outcomes for health, the environment, sustainable consumption, social integration, and equity.

We can quantify how connected street networks are with the Street Network Disconnectedness Index (SNDi).

SNDi -- our measure of street-network sprawl (disconnectedness)

The SNDi is a comprehensive measurement of “sprawl”. It captures:

A higher SNDi means less-connected streets – i.e., more sprawl. For the 10137 cities in our dataset, the average SNDi is 2.25, with half of the cities' SNDis falling between 1.08 and 3.25.

More information on the sprawl index can be found in these research papers:

To see the state of street-network sprawl across the globe, visit the sprawlmap.

Luján: city in Buenos Aires, Argentina

What exactly constitutes the spatial extent of the city? For these aggregations, we used the Global Human Settlement Layer Urban Center Database (GHS-UCDB) to define the boundaries of the city. These cities -- or urban centers -- cover areas that are densely populated and built-up, and so may extend beyond the spatial borders of these cities that we may be familiar with. The GHS area is shaded in blue.

View Luján, Argentina on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Luján as of 2014, the overall level of street-network sprawl is 0.52, which is relatively well-connected.

Trends in street network construction: The SNDis of street construction for the respective time periods are 0.3, 0.99, 2.13 and 7.45. In each period, new street development in Luján steadily grows more disconnected than in the last.

Quantity of street network construction: The street network in Luján spans a total of 304 kilometers. It is dominated by roads constructed prior to 1975. These roads have an SNDi of 0.3, which is very well-connected.

Effect on the aggregate network: New construction in each period adds to the total stock of streets, but does not change streets that have already been built. Therefore, it has a limited effect on the street network as a whole. The SNDis of the aggregate street network in the respective time periods are 0.3, 0.45, 0.49 and 0.52. Overall, the SNDi of the aggregate street network has risen: the street network in Luján has become more disconnected. This increase has slowed: between 1975 and 1976-1990, SNDi rose by 0.15 points, but between 1991-2000 and 2001-2014, it rose by just 0.02.

Luján and Buenos Aires follow the same trend in the disconnectivity of their street network constructions. The SNDi for both of these rose steadily.

How do development practices in Luján fare in comparison to others in Buenos Aires? Most recently in 2001-2014, street construction in Luján was the 1st-most disconnected out of the 17 cities in Buenos Aires. Its position in the ranks since 1975 has risen; relative to other cities in Buenos Aires, street construction in Luján has become more disconnected. Luján ranked 4th in 1975, 6th in 1976-1990, 4th in 1991-2000 and 1st in 2001-2014.

Luján and Argentina follow the same trend in the disconnectivity of their street network constructions. The SNDi for both of these rose steadily.

How do development practices in Luján fare in comparison to others in Argentina? Most recently in 2001-2014, street construction in Luján was the 1st-most disconnected out of the 70 cities in Argentina. Its position in the ranks since 1975 has risen; relative to other cities in Argentina, street construction in Luján has become more disconnected. Luján ranked 21st in 1975, 12th in 1976-1990, 11th in 1991-2000 and 1st in 2001-2014.

Luján and Buenos Aires follow the same trend in the disconnectivity of their aggregate street networks. The SNDi for both of these rose steadily.

To date, Luján is the 5th-most disconnected out of the 17 cities in Buenos Aires. Its position in the ranks since 1975 has fallen; relative to other cities in Buenos Aires, the street network in Luján has become more connected. Luján ranked 4th in 1975, 5th in 1976-1990, 5th in 1991-2000 and 5th in 2001-2014.

Luján and Argentina follow the same trend in the disconnectivity of their aggregate street networks. The SNDi for both of these rose steadily.

To date, Luján is the 22nd-most disconnected out of the 70 cities in Argentina. Its position in the ranks since 1975 has fallen; relative to other cities in Argentina, the street network in Luján has become more connected. Luján ranked 21st in 1975, 21st in 1976-1990, 21st in 1991-2000 and 22nd in 2001-2014.

As of 2015, Luján had a built-up area of 11.78 square kilometers, and a population of 66303 people.

These are some other cities with approximately the same population: