Street-network Sprawl in Três Rios, 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.

Três Rios: city in Rio de Janeiro, 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 Três Rios, Brazil on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Três Rios as of 2014, the overall level of street-network sprawl is 4.9, which is highly disconnected.

Trends in street network construction: The SNDis of street construction for the respective time periods are 3.8, 5.17, 8.96 and 7.94. Street construction in Três Rios increased in disconnectivity initially but has since improved. The streets constructed in 1991-2000 were the most disconnected.

Quantity of street network construction: The street network in Três Rios spans a total of 149 kilometers. It is dominated by roads constructed in 1976-1990. These roads have an SNDi of 5.17, which is highly disconnected.

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 3.8, 4.74, 4.84 and 4.9. Overall, the SNDi of the aggregate street network has risen: the street network in Três Rios has become more disconnected. This increase has slowed: between 1975 and 1976-1990, SNDi rose by 0.94 points, but between 1991-2000 and 2001-2014, it rose by just 0.06.

Três Rios and Rio de Janeiro do not follow the same trend in the disconnectivity of their street network constructions. The SNDi in Três Rios peaked in 1991-2000, while the SNDi of street constructions in Rio de Janeiro rose steadily.

How do development practices in Três Rios fare in comparison to others in Rio de Janeiro? Most recently in 2001-2014, street construction in Três Rios was the 6th-most disconnected out of the 18 cities in Rio de Janeiro. Its position in the ranks since 1975 has not changed. Três Rios ranked 6th in 1975, 6th in 1976-1990, 5th in 1991-2000 and 6th in 2001-2014.

Três Rios and Brazil do not follow the same trend in the disconnectivity of their street network constructions. The SNDi in Três Rios peaked in 1991-2000, while the SNDi of street constructions in Brazil rose steadily.

How do development practices in Três Rios fare in comparison to others in Brazil? Most recently in 2001-2014, street construction in Três Rios was the 15th-most disconnected out of the 348 cities in Brazil. Its position in the ranks since 1975 has risen; relative to other cities in Brazil, street construction in Três Rios has become more disconnected. Três Rios ranked 21st in 1975, 19th in 1976-1990, 10th in 1991-2000 and 15th in 2001-2014.

Três Rios and Rio de Janeiro follow the same trend in the disconnectivity of their aggregate street networks. The SNDi for both of these rose steadily.

To date, Três Rios is the 5th-most disconnected out of the 18 cities in Rio de Janeiro. Its position in the ranks since 1975 has risen; relative to other cities in Rio de Janeiro, the street network in Três Rios has become more disconnected. Três Rios ranked 6th in 1975, 5th in 1976-1990, 5th in 1991-2000 and 5th in 2001-2014.

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

To date, Três Rios is the 9th-most disconnected out of the 348 cities in Brazil. Its position in the ranks since 1975 has risen; relative to other cities in Brazil, the street network in Três Rios has become more disconnected. Três Rios ranked 21st in 1975, 11th in 1976-1990, 9th in 1991-2000 and 9th in 2001-2014.

As of 2015, Três Rios had a built-up area of 4.49 square kilometers, and a population of 59814 people.

These are some other cities with approximately the same population: