Street-network Sprawl in Sha Tin, China

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.

Sha Tin: city in China

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 Sha Tin, China on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Sha Tin as of 2014, the overall level of street-network sprawl is 1.9, which is relatively well-connected.

Trends in street network construction: The SNDis of street construction for the respective time periods are 1.58, 2.38, 3.28 and 5.53. In each period, new street development in Sha Tin steadily grows more disconnected than in the last.

Quantity of street network construction: The street network in Sha Tin spans a total of 589 kilometers. It is dominated by roads constructed prior to 1975. These roads have an SNDi of 1.58, 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 1.58, 1.87, 1.88 and 1.9. Overall, the SNDi of the aggregate street network has risen: the street network in Sha Tin has become more disconnected. This increase has slowed: between 1975 and 1976-1990, SNDi rose by 0.29 points, but between 1991-2000 and 2001-2014, it rose by just 0.02.

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

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

Sha Tin and China do not follow the same trend in the disconnectivity of their street network constructions. The SNDi in Sha Tin rose steadily, while the SNDi of street constructions in China followed a zig-zag trend with an overall increase.

How do development practices in Sha Tin fare in comparison to others in China? Most recently in 2001-2014, street construction in Sha Tin was the 75th-most disconnected out of the 1651 cities in China. Its position in the ranks since 1975 has risen; relative to other cities in China, street construction in Sha Tin has become more disconnected. Sha Tin ranked 635th in 1975, 496th in 1976-1990, 199th in 1991-2000 and 75th in 2001-2014.

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

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

Sha Tin and China follow the same trend in the disconnectivity of their aggregate street networks. The SNDi for both of these rose steadily.

To date, Sha Tin is the 743rd-most disconnected out of the 1651 cities in China. Its position in the ranks since 1975 has fallen; relative to other cities in China, the street network in Sha Tin has become more connected. Sha Tin ranked 635th in 1975, 719th in 1976-1990, 718th in 1991-2000 and 743rd in 2001-2014.

As of 2015, Sha Tin had a built-up area of 38.47 square kilometers, and a population of 1234633 people.

These are some other cities with approximately the same population: