Urban sprawl and drinking water services in an African city: the case of Bukavu in DR Congo

Abstract

This study evaluates urban growth and access to drinking water in Bukavu from 1980 to 2024, combining diachronic Landsat image analysis, demographic and geospatial data, and household surveys. Bukavu’s population rose from 280,000 to over 2 million, with an annual growth rate of 4.57%, doubling every 16 years. The urbanized area expanded from 17 km2 in 1984 to nearly 50 km2 in 2024, with progressive densification in risk-prone zones such as steep slopes and wetlands. Theoretical access to drinking water is 61%, falling below 20% in informal neighborhoods. REGIDESO produces 25,000–30,000 m3/day, while the estimated demand is 70,000–72,000 m3/day, creating a deficit of over 30,000 m3/day. Households rely on public standpipes (45%), unimproved sources (33%), and the parallel market (44%), with average collection times of 45 min. High-density areas show elevated health risks, with 57% of water samples contaminated by Salmonella and 36% contaminated by E. coli. Land tenure insecurity affects 29.7% of households. Statistical analysis indicates strong correlations between distance and collection time (r = 0.963) and moderate correlations with disease occurrence (distance r = 0.582; time r = 0.411). These findings demonstrate that rapid urban sprawl, informal settlement, and weak institutional capacity significantly constrain water access, contributing to health risks and highlighting broader implications for African cities experiencing similar growth patterns.