Urban Thirst
Many cities are growing in locations with scarce rainfall and limited water retention, often becoming elongated and sprawled. This makes it harder to deliver essential services, including water and sanitation.
This visualization presents findings from the study “Urban Sprawl Is Associated with Reduced Access and Increased Costs of Water and Sanitation.” The research covers 100+ cities across Asia, Africa, and Latin America, home to 650 million people and 183 million buildings.
To make comparisons across cities easier, the study introduces Sparseness, a measure of how the population is distributed across the city, based on Remoteness—the distance of any location to the city center (0–30). Sparseness is the population-weighted average of remoteness across all locations in a city.
Remoteness categories (area-level):
- Central (remoteness ≤ 3)
- Inner (3 < remoteness ≤ 5)
- Suburban (5 < remoteness ≤ 9.5)
- Peri-urban (remoteness > 9.5)
City size categories (by population):
- Small (<1.5M)
- Medium (1.5–3M)
- Large (3–10M)
- Mega (>10M)
This framework helps us understand how urban form—population spread and density—affects water access, infrastructure proximity, and service costs.
Paper
Rafael Prieto-Curiel, Pavel Luengas-Sierra, Christian Borja-Vega. Urban Sprawl Is Associated with Reduced Access and Increased Costs of Water and Sanitation. Nature Cities . https://doi.org/10.1038/s44284-025-00338-3
Credits
This is a collaborative work between the Complexity Science Hub and the World Bank.
