Cecilia Lee, Illustrations Editor

A new study by Yale researchers found that inequalities in infrastructure can prevent sustainable urbanization.

As countries around the globe become increasingly urbanized, socioeconomic inequalities have been observed to rise in those countries as well. Led by Bhartendu Pandey GRD ’18 ENV ’21 and co-authored by Karen Seto, professor of geography and urbanization study at the Yale School of the Environment, and Christa Brelsford, research scientist at Oak Ridge National Laboratory, the study set out to determine if and how inequalities in infrastructure prevent sustainable urbanization. 

The team chose to analyze infrastructure distribution in South Africa and India due to the high levels of urbanization and socioeconomic disparities present in the countries. Pandey defined urbanization as both the expansion of cities and the tendency of people to move into these urban areas from rural areas. 

“The properties of infrastructure may not be similar to that of the economic variables, so we had to come up with some empirical framework that captures these properties,” Pandey explained.

Infrastructure analyzed by the study included tap water, sanitation, housing and electricity. Access to each of these was measured through the use of census data from both South Africa and India as well as satellite imaging technology. 

According to Pandey, light pollution is a good way to measure the level of infrastructure an area has, as so much goes into just lighting one bulb, including the construction of an electrical grid and access to electricians. 

In the study, inequality refers to how much preferential bias affects the distribution of the available infrastructure, Pandey explained. According to Brelsford, preferential bias is a framework for how infrastructure is distributed because it accounts for the logical observation that more infrastructure is likely to be added during urbanization in places where it already exists.

“If you’re going to build a power grid, or if you’re going to build a water system, it’s easiest to build your water main and then you connect one house at a time,” Brelsford explained. “And those houses you connect, are going to be close to where you build your big pipes … and so it very naturally means that these … places get access to these kinds of infrastructure preferentially.”

Pandey explained the concept further through an example using cups. Imagine ten cups, he said, and try to fill them with water from one jug in the most equitable way possible — all at the same time, which is impossible. The fastest way to fill the cups would be to completely fill one and then move on to the next, continuing until all of the cups are full. However, when one cup is completely filled and the rest are empty, the greatest level of inequality exists. To successfully maintain equity, one could fill each cup with only a small amount of water before moving on to the next, but it would take much longer to fill all of the cups completely.

A similar problem arises with infrastructure expansion. It seems impossible to distribute the available infrastructure evenly when one must build off of what already exists. Furthermore, increasing the infrastructure in small amounts throughout a region would take longer than completely equipping an area with the necessary infrastructure before moving on to the next. A more equitable approach seems unfeasible with the fast-paced rate of urbanization in the analyzed countries, according to Pandey. 

Analysis of census and satellite data found that there is more infrastructure inequality in urban areas as compared to rural areas, with those in urban areas having greater access to infrastructure than those in rural areas. 

These differences in access to infrastructure will only be exacerbated by urbanization due to the preferential bias framework. 

“The empirical framework, and all of these findings put together took us to our major conclusion, which is that when countries are urbanizing, they seem to traverse this very unequal path of infrastructural distributions, so that means infrastructural inequalities are very much engrained in urbanization,” Pandey said. “It’s not just an outcome of urbanization, it’s a characteristic of urbanization.”

The team looked to determine if the patterns in socioeconomic inequality in South Africa and India correlated with the observed patterns of infrastructure inequality within the respective country, but they did not find patterns due to the varying nature of socioeconomics and infrastructure. 

“Economic inequality is unbounded, there is functionally no limit in the amount of wealth one person can accumulate, but once you have water, you have water,” Brelsford explained. “You do not need a reservoir full of it. Socioeconomic characteristics and infrastructural characteristics are very different in that way.” 

Infrastructure inequalities are essential to address in order to urbanize sustainably, Pandey and Brelsford explained. 

The study, which was published in PNAS, places infrastructure inequality in the broader context of how issues arising from urbanization are addressed. 

“We can better understand and address equitable urbanization by bringing infrastructure inequality to the fore,” the researchers wrote in the study. “Infrastructure inequality has been given less attention than economic inequality.” 

According to Brelsford, infrastructure inequalities grow and change with urbanization, and future research should look to investigate how urbanization and equitable access to infrastructure can take place simultaneously. 

As of 2020, the population of India was 1.38 billion people and the population of South Africa was 59.31 million, according to the World Bank. 

CHLOE NIELD