Street-network Sprawl in Rajapalaiyam, India

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.

Rajapalaiyam: city in Tamil Nadu, India

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 Rajapalaiyam, India on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Rajapalaiyam as of 2014, the overall level of street-network sprawl is 3.52, which is highly disconnected.

Trends in street network construction: The SNDis of street construction for the respective time periods are 1.51, 3.35, nan and 3.44. Data was not available in 1991-2000.

Quantity of street network construction: The street network in Rajapalaiyam spans a total of 124 kilometers. It is dominated by roads constructed in 2001-2014. These roads have an SNDi of 3.44, 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 1.51, 3.08, 3.65 and 3.52. The aggregate street network in Rajapalaiyam increased in disconnectivity initially,but the trend has turned around after 2000.

Rajapalaiyam and Tamil Nadu 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 Tamil Nadu rose steadily.

How do development practices in Rajapalaiyam fare in comparison to others in Tamil Nadu? Most recently in 2001-2014, street construction in Rajapalaiyam was the 70th-most disconnected out of the 151 cities in Tamil Nadu. Its position in the ranks since 1975 has risen; relative to other cities in Tamil Nadu, street construction in Rajapalaiyam has become more disconnected. Rajapalaiyam ranked 56th in 1975, 34th in 1976-1990 and 70th in 2001-2014. There was no ranking in 1991-2000 due to unavailable data.

Rajapalaiyam and India 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 India rose steadily.

How do development practices in Rajapalaiyam fare in comparison to others in India? Most recently in 2001-2014, street construction in Rajapalaiyam was the 569th-most disconnected out of the 1716 cities in India. Its position in the ranks since 1975 has risen; relative to other cities in India, street construction in Rajapalaiyam has become more disconnected. Rajapalaiyam ranked 572nd in 1975, 351st in 1976-1990 and 569th in 2001-2014. There was no ranking in 1991-2000 due to unavailable data.

Rajapalaiyam and Tamil Nadu do not follow the same trend in the disconnectivity of their aggregate street networks. The SNDi in Rajapalaiyam peaked in 1991-2000, while the SNDi of street constructions in Tamil Nadu rose steadily.

To date, Rajapalaiyam is the 40th-most disconnected out of the 151 cities in Tamil Nadu. Its position in the ranks since 1975 has risen; relative to other cities in Tamil Nadu, the street network in Rajapalaiyam has become more disconnected. Rajapalaiyam ranked 56th in 1975, 44th in 1976-1990, 31st in 1991-2000 and 40th in 2001-2014.

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

To date, Rajapalaiyam is the 463rd-most disconnected out of the 1716 cities in India. Its position in the ranks since 1975 has risen; relative to other cities in India, the street network in Rajapalaiyam has become more disconnected. Rajapalaiyam ranked 572nd in 1975, 425th in 1976-1990, 332nd in 1991-2000 and 463rd in 2001-2014.

As of 2015, Rajapalaiyam had a built-up area of 7.17 square kilometers, and a population of 297177 people.

These are some other cities with approximately the same population: