Street-network Sprawl in San Miguel de Allende, Mexico

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.

San Miguel de Allende: city in Guanajuato, Mexico

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 San Miguel de Allende, Mexico on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in San Miguel de Allende as of 2014, the overall level of street-network sprawl is 2.82, which is in the 40th to 60th percentile of disconnectedness.

Trends in street network construction: The SNDis of street construction for the respective time periods are 2.51, 3.0, 2.52 and 5.42. Disconnectivity in street construction in San Miguel de Allende follows a zig-zag trend. In 1975, street construction was most disconnected, while construction was most connected in 2001-2014.

Quantity of street network construction: The street network in San Miguel de Allende spans a total of 270 kilometers. The period with the greatest volume of street construction was 1991-2000. These roads have an SNDi of 2.52, which is in the 40th to 60th percentile of disconnectedness.

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 2.51, 2.8, 2.67 and 2.82. Disconnectivity in San Miguel de Allende's street network follows a zig-zag trend. In 1975, the city was most disconnected; while it was most connected in 2001-2014.

San Miguel de Allende and Guanajuato do not follow the same trend in the disconnectivity of their street network constructions. The SNDi in San Miguel de Allende followed a zig-zag trend with an overall increase, while the SNDi of street constructions in Guanajuato rose steadily.

How do development practices in San Miguel de Allende fare in comparison to others in Guanajuato? Most recently in 2001-2014, street construction in San Miguel de Allende was the 3rd-most disconnected out of the 15 cities in Guanajuato. Its position in the ranks since 1975 has fallen; relative to other cities in Guanajuato, street construction in San Miguel de Allende has become more connected. San Miguel de Allende ranked 2nd in 1975, 2nd in 1976-1990, 11th in 1991-2000 and 3rd in 2001-2014.

San Miguel de Allende and Mexico do not follow the same trend in the disconnectivity of their street network constructions. The SNDi in San Miguel de Allende followed a zig-zag trend with an overall increase, while the SNDi of street constructions in Mexico rose steadily.

How do development practices in San Miguel de Allende fare in comparison to others in Mexico? Most recently in 2001-2014, street construction in San Miguel de Allende was the 25th-most disconnected out of the 166 cities in Mexico. Its position in the ranks since 1975 has fallen; relative to other cities in Mexico, street construction in San Miguel de Allende has become more connected. San Miguel de Allende ranked 21st in 1975, 28th in 1976-1990, 85th in 1991-2000 and 25th in 2001-2014.

San Miguel de Allende and Guanajuato do not follow the same trend in the disconnectivity of their aggregate street networks. The SNDi in San Miguel de Allende followed a zig-zag trend with an overall increase, while the SNDi of street constructions in Guanajuato rose steadily.

To date, San Miguel de Allende is the 2nd-most disconnected out of the 15 cities in Guanajuato. Its position in the ranks since 1975 has not changed. San Miguel de Allende ranked 2nd in 1975, 2nd in 1976-1990, 2nd in 1991-2000 and 2nd in 2001-2014.

San Miguel de Allende and Mexico do not follow the same trend in the disconnectivity of their aggregate street networks. The SNDi in San Miguel de Allende followed a zig-zag trend with an overall increase, while the SNDi of street constructions in Mexico rose steadily.

To date, San Miguel de Allende is the 33rd-most disconnected out of the 166 cities in Mexico. Its position in the ranks since 1975 has fallen; relative to other cities in Mexico, the street network in San Miguel de Allende has become more connected. San Miguel de Allende ranked 21st in 1975, 22nd in 1976-1990, 30th in 1991-2000 and 33rd in 2001-2014.

As of 2015, San Miguel de Allende had a built-up area of 8.9 square kilometers, and a population of 79280 people.

These are some other cities with approximately the same population: