Street-network Sprawl in Alagoinhas, Brazil

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.

Alagoinhas: city in Bahia, Brazil

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 Alagoinhas, Brazil on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Alagoinhas as of 2014, the overall level of street-network sprawl is 2.13, which is relatively well-connected.

Trends in street network construction: The SNDis of street construction for the respective time periods are 1.94, nan, 3.78 and 2.55. Data was not available in 1976-1990.

Quantity of street network construction: The street network in Alagoinhas spans a total of 346 kilometers. It is dominated by roads constructed prior to 1975. These roads have an SNDi of 1.94, which is relatively 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 1.94, 1.94, 2.09 and 2.13. Overall, the SNDi of the aggregate street network has risen: the street network in Alagoinhas has become more disconnected.

Alagoinhas and Bahia do not follow the same trend in the disconnectivity of their street network constructions. There was not enough data from the city, while the SNDi of street constructions in Bahia was at its lowest in 1976-1990.

How do development practices in Alagoinhas fare in comparison to others in Bahia? Most recently in 2001-2014, street construction in Alagoinhas was the 13th-most disconnected out of the 21 cities in Bahia. Its position in the ranks since 1975 has fallen; relative to other cities in Bahia, street construction in Alagoinhas has become more connected. Alagoinhas ranked 8th in 1975, 7th in 1991-2000 and 13th in 2001-2014. There was no ranking in 1976-1990 due to unavailable data.

Alagoinhas and Brazil do not follow the same trend in the disconnectivity of their street network constructions. There was not enough data from the city, while the SNDi of street constructions in Brazil rose steadily.

How do development practices in Alagoinhas fare in comparison to others in Brazil? Most recently in 2001-2014, street construction in Alagoinhas was the 180th-most disconnected out of the 348 cities in Brazil. Its position in the ranks since 1975 has fallen; relative to other cities in Brazil, street construction in Alagoinhas has become more connected. Alagoinhas ranked 87th in 1975, 82nd in 1991-2000 and 180th in 2001-2014. There was no ranking in 1976-1990 due to unavailable data.

Alagoinhas and Bahia do not follow the same trend in the disconnectivity of their aggregate street networks. The SNDi in Alagoinhas rose steadily, while the SNDi of street constructions in Bahia was at its lowest in 1976-1990.

To date, Alagoinhas is the 10th-most disconnected out of the 21 cities in Bahia. Its position in the ranks since 1975 has fallen; relative to other cities in Bahia, the street network in Alagoinhas has become more connected. Alagoinhas ranked 8th in 1975, 8th in 1976-1990, 9th in 1991-2000 and 10th in 2001-2014.

Alagoinhas and Brazil do not follow the same trend in the disconnectivity of their aggregate street networks. The SNDi in Alagoinhas rose steadily, while the SNDi of street constructions in Brazil rose steadily.

To date, Alagoinhas is the 115th-most disconnected out of the 348 cities in Brazil. Its position in the ranks since 1975 has fallen; relative to other cities in Brazil, the street network in Alagoinhas has become more connected. Alagoinhas ranked 87th in 1975, 109th in 1976-1990, 107th in 1991-2000 and 115th in 2001-2014.

As of 2015, Alagoinhas had a built-up area of 9.94 square kilometers, and a population of 120505 people.

These are some other cities with approximately the same population: