Street-network Sprawl in Fukaya, Japan

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.

Fukaya: city in Saitama, Japan

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 Fukaya, Japan on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Fukaya as of 2014, the overall level of street-network sprawl is 0.61, which is relatively well-connected.

Trends in street network construction: The SNDis of street construction for the respective time periods are 0.83, 0.51, -0.31 and 0.49. The disconnectivity of new streets constructed in Fukaya fell, then rose. In 1991-2000, new street layouts were the most connected.

Quantity of street network construction: The street network in Fukaya spans a total of 660 kilometers. It is dominated by roads constructed in 1976-1990. These roads have an SNDi of 0.51, 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 0.83, 0.62, 0.61 and 0.61. Overall, the SNDi of the aggregate street network has fallen: the street network in Fukaya has become more connected.

Fukaya and Saitama do not follow the same trend in the disconnectivity of their street network constructions. The SNDi in Fukaya was at its lowest in 1991-2000, while the SNDi of street constructions in Saitama peaked in 1991-2000.

How do development practices in Fukaya fare in comparison to others in Saitama? Most recently in 2001-2014, street construction in Fukaya was the 2nd-most disconnected out of the 2 cities in Saitama. Its position in the ranks since 1975 has fallen; relative to other cities in Saitama, street construction in Fukaya has become more connected. Fukaya ranked 1st in 1975, 2nd in 1976-1990, 2nd in 1991-2000 and 2nd in 2001-2014.

Fukaya and Japan do not follow the same trend in the disconnectivity of their street network constructions. The SNDi in Fukaya was at its lowest in 1991-2000, while the SNDi of street constructions in Japan peaked in 1991-2000.

How do development practices in Fukaya fare in comparison to others in Japan? Most recently in 2001-2014, street construction in Fukaya was the 88th-most disconnected out of the 109 cities in Japan. Its position in the ranks since 1975 has fallen; relative to other cities in Japan, street construction in Fukaya has become more connected. Fukaya ranked 79th in 1975, 92nd in 1976-1990, 102nd in 1991-2000 and 88th in 2001-2014.

Fukaya and Saitama do not follow the same trend in the disconnectivity of their aggregate street networks. The SNDi in Fukaya fell steadily, while the SNDi of street constructions in Saitama peaked in 1991-2000.

To date, Fukaya is the 2nd-most disconnected out of the 2 cities in Saitama. Its position in the ranks since 1975 has fallen; relative to other cities in Saitama, the street network in Fukaya has become more connected. Fukaya ranked 1st in 1975, 2nd in 1976-1990, 2nd in 1991-2000 and 2nd in 2001-2014.

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

To date, Fukaya is the 97th-most disconnected out of the 109 cities in Japan. Its position in the ranks since 1975 has fallen; relative to other cities in Japan, the street network in Fukaya has become more connected. Fukaya ranked 79th in 1975, 95th in 1976-1990, 97th in 1991-2000 and 97th in 2001-2014.

As of 2015, Fukaya had a built-up area of 27.9 square kilometers, and a population of 72000 people.

These are some other cities with approximately the same population: