Street-network Sprawl in Yên Bái, 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.

Yên Bái: city in 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 Yên Bái, Vietnam on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Yên Bái as of 2014, the overall level of street-network sprawl is 4.46, which is highly disconnected.

Trends in street network construction: The SNDis of street construction for the respective time periods are 2.76, 2.66, 1.62 and 5.64. The disconnectivity of new streets constructed in Yên Bái fell, then rose. In 1991-2000, new street layouts were the most connected.

Quantity of street network construction: The street network in Yên Bái spans a total of 310 kilometers. It is dominated by roads constructed in 2001-2014. These roads have an SNDi of 5.64, 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 2.76, 2.9, 2.85 and 4.46. Disconnectivity in Yên Bái's street network follows a zig-zag trend. In 1975, the city was most disconnected; while it was most connected in 2001-2014.

Yên Bái and Yên Bái do not follow the same trend in the disconnectivity of their street network constructions. The SNDi in Yên Bái was at its lowest in 1991-2000, while the SNDi of street constructions in Yên Bái followed a zig-zag trend with an overall increase.

How do development practices in Yên Bái fare in comparison to others in Yên Bái? Most recently in 2001-2014, street construction in Yên Bái was the 1st-most disconnected out of the 1 cities in Yên Bái. Its position in the ranks since 1975 has not changed. Yên Bái ranked 1st in 1975, 1st in 1976-1990, 1st in 1991-2000 and 1st in 2001-2014.

Yên Bái and Vietnam do not follow the same trend in the disconnectivity of their street network constructions. The SNDi in Yên Bái was at its lowest in 1991-2000, while the SNDi of street constructions in Vietnam rose steadily.

How do development practices in Yên Bái fare in comparison to others in Vietnam? Most recently in 2001-2014, street construction in Yên Bái was the 7th-most disconnected out of the 129 cities in Vietnam. Its position in the ranks since 1975 has risen; relative to other cities in Vietnam, street construction in Yên Bái has become more disconnected. Yên Bái ranked 32nd in 1975, 43rd in 1976-1990, 75th in 1991-2000 and 7th in 2001-2014.

Yên Bái and Yên Bái follow the same trend in the disconnectivity of their aggregate street networks. The SNDi for both of these followed a zig-zag trend with an overall increase.

To date, Yên Bái is the 1st-most disconnected out of the 1 cities in Yên Bái. Its position in the ranks since 1975 has not changed. Yên Bái ranked 1st in 1975, 1st in 1976-1990, 1st in 1991-2000 and 1st in 2001-2014.

Yên Bái and Vietnam do not follow the same trend in the disconnectivity of their aggregate street networks. The SNDi in Yên Bái followed a zig-zag trend with an overall increase, while the SNDi of street constructions in Vietnam rose steadily.

To date, Yên Bái is the 14th-most disconnected out of the 129 cities in Vietnam. Its position in the ranks since 1975 has risen; relative to other cities in Vietnam, the street network in Yên Bái has become more disconnected. Yên Bái ranked 32nd in 1975, 36th in 1976-1990, 39th in 1991-2000 and 14th in 2001-2014.

As of 2015, Yên Bái had a built-up area of 3.81 square kilometers, and a population of 102148 people.

These are some other cities with approximately the same population: