Street-network Sprawl in Dumaguete, Philippines

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.

Dumaguete: city in Negros Oriental, Philippines

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 Dumaguete, Philippines on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Dumaguete as of 2014, the overall level of street-network sprawl is 4.3, which is highly disconnected.

Trends in street network construction: The SNDis of street construction for the respective time periods are 2.99, 4.59, 5.4 and 4.81. Street construction in Dumaguete increased in disconnectivity initially but has since improved. The streets constructed in 1991-2000 were the most disconnected.

Quantity of street network construction: The street network in Dumaguete spans a total of 211 kilometers. The period with the greatest volume of street construction was 1976-1990. These roads have an SNDi of 4.59, 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 2.99, 3.96, 4.17 and 4.3. Overall, the SNDi of the aggregate street network has risen: the street network in Dumaguete has become more disconnected. This increase has slowed: between 1975 and 1976-1990, SNDi rose by 0.97 points, but between 1991-2000 and 2001-2014, it rose by just 0.13.

Dumaguete and Negros Oriental follow the same trend in the disconnectivity of their street network constructions. The SNDi for both of these peaked in 1991-2000.

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

Dumaguete and Philippines do not follow the same trend in the disconnectivity of their street network constructions. The SNDi in Dumaguete peaked in 1991-2000, while the SNDi of street constructions in Philippines rose steadily.

How do development practices in Dumaguete fare in comparison to others in Philippines? Most recently in 2001-2014, street construction in Dumaguete was the 55th-most disconnected out of the 89 cities in Philippines. Its position in the ranks since 1975 has fallen; relative to other cities in Philippines, street construction in Dumaguete has become more connected. Dumaguete ranked 38th in 1975, 37th in 1976-1990, 30th in 1991-2000 and 55th in 2001-2014.

Dumaguete and Negros Oriental follow the same trend in the disconnectivity of their aggregate street networks. The SNDi for both of these rose steadily.

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

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

To date, Dumaguete is the 41st-most disconnected out of the 89 cities in Philippines. Its position in the ranks since 1975 has fallen; relative to other cities in Philippines, the street network in Dumaguete has become more connected. Dumaguete ranked 38th in 1975, 41st in 1976-1990, 40th in 1991-2000 and 41st in 2001-2014.

As of 2015, Dumaguete had a built-up area of 5.61 square kilometers, and a population of 166126 people.

These are some other cities with approximately the same population: