Street-network Sprawl in Hillcrest, New Zealand

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.

Hillcrest: city in Auckland, New Zealand

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 Hillcrest, New Zealand on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Hillcrest as of 2014, the overall level of street-network sprawl is 4.04, which is highly disconnected.

Trends in street network construction: The SNDis of street construction for the respective time periods are 3.98, nan, 6.85 and 3.94. Data was not available in 1976-1990.

Quantity of street network construction: The street network in Hillcrest spans a total of 771 kilometers. It is dominated by roads constructed prior to 1975. These roads have an SNDi of 3.98, 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 3.98, 3.98, 4.04 and 4.04. Disconnectivity in Hillcrest's street network follows a zig-zag trend. In 1975, the city was most disconnected; while it was most connected in 1991-2000.

Hillcrest and Auckland do not follow the same trend in the disconnectivity of their street network constructions. There was not enough data from the city, as well as the Auckland's street network construction.

How do development practices in Hillcrest fare in comparison to others in Auckland? Most recently in 2001-2014, street construction in Hillcrest was the 1st-most disconnected out of the 2 cities in Auckland. Its position in the ranks since 1975 has not changed. Hillcrest ranked 1st in 1975, 1st in 1991-2000 and 1st in 2001-2014. There was no ranking in 1976-1990 due to unavailable data.

Hillcrest and New Zealand do not follow the same trend in the disconnectivity of their street network constructions. There was not enough data from the city, as well as the New Zealand's street network construction.

How do development practices in Hillcrest fare in comparison to others in New Zealand? Most recently in 2001-2014, street construction in Hillcrest was the 4th-most disconnected out of the 8 cities in New Zealand. Its position in the ranks since 1975 has fallen; relative to other cities in New Zealand, street construction in Hillcrest has become more connected. Hillcrest ranked 2nd in 1975, 3rd in 1991-2000 and 4th in 2001-2014. There was no ranking in 1976-1990 due to unavailable data.

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

To date, Hillcrest is the 1st-most disconnected out of the 2 cities in Auckland. Its position in the ranks since 1975 has not changed. Hillcrest ranked 1st in 1975, 1st in 1976-1990, 1st in 1991-2000 and 1st in 2001-2014.

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

To date, Hillcrest is the 3rd-most disconnected out of the 8 cities in New Zealand. Its position in the ranks since 1975 has fallen; relative to other cities in New Zealand, the street network in Hillcrest has become more connected. Hillcrest ranked 2nd in 1975, 2nd in 1976-1990, 3rd in 1991-2000 and 3rd in 2001-2014.

As of 2015, Hillcrest had a built-up area of 56.73 square kilometers, and a population of 219043 people.

These are some other cities with approximately the same population: