Street-network Sprawl in Tây Đằng, Vietnam

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.

Tây Đằng: city in Hà Nội, Vietnam

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 Tây Đằng, Vietnam on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Tây Đằng as of 2014, the overall level of street-network sprawl is -1.37, which is very well-connected.

Trends in street network construction: The SNDis of street construction for the respective time periods are -1.0, nan, nan and nan. Data was not available in 1976-1990, 1991-2000 and 2001-2014.

Quantity of street network construction: The street network in Tây Đằng spans a total of 66 kilometers. It is dominated by roads constructed prior to 1975. These roads have an SNDi of -1.0, 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 -1.0, -1.37, -1.37 and -1.37. Overall, the SNDi of the aggregate street network has fallen: the street network in Tây Đằng has become more connected.

Tây Đằng and Hà Nội 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 Hà Nội was at its lowest in 1991-2000.

How do development practices in Tây Đằng fare in comparison to others in Hà Nội? out of the 11 cities in Hà Nội. Tây Đằng ranked 8th in 1975. There was no ranking in 1976-1990, 1991-2000, and 2001-2014 due to unavailable data.

Tây Đằng and Vietnam 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 Vietnam rose steadily.

How do development practices in Tây Đằng fare in comparison to others in Vietnam? out of the 129 cities in Vietnam. Tây Đằng ranked 93rd in 1975. There was no ranking in 1976-1990, 1991-2000, and 2001-2014 due to unavailable data.

Tây Đằng and Hà Nội do not follow the same trend in the disconnectivity of their aggregate street networks. The SNDi in Tây Đằng fell steadily, while the SNDi of street constructions in Hà Nội fell steadily.

To date, Tây Đằng is the 11th-most disconnected out of the 11 cities in Hà Nội. Its position in the ranks since 1975 has fallen; relative to other cities in Hà Nội, the street network in Tây Đằng has become more connected. Tây Đằng ranked 8th in 1975, 10th in 1976-1990, 11th in 1991-2000 and 11th in 2001-2014.

Tây Đằng and Vietnam do not follow the same trend in the disconnectivity of their aggregate street networks. The SNDi in Tây Đằng fell steadily, while the SNDi of street constructions in Vietnam rose steadily.

To date, Tây Đằng is the 129th-most disconnected out of the 129 cities in Vietnam. Its position in the ranks since 1975 has fallen; relative to other cities in Vietnam, the street network in Tây Đằng has become more connected. Tây Đằng ranked 93rd in 1975, 123rd in 1976-1990, 128th in 1991-2000 and 129th in 2001-2014.

As of 2015, Tây Đằng had a built-up area of 3.12 square kilometers, and a population of 62025 people.

These are some other cities with approximately the same population: