Informal settlement vulnerability to multi-hazards in eThekwini, South Africa: An AHP and geospatial approach

Abstract

Informal settlements in rapidly urbanising contexts face heightened exposure to climate-related hazards due to precarious locations, inadequate infrastructure, and socio-economic marginalisation. This study assesses the multi-hazard susceptibility of informal settlements in the eThekwini Metropolitan Municipality, South Africa, with a focus on floods, fires, and landslides. A Geographic Information Systems (GIS)-based multi-criteria decision-making approach was employed using the Analytical Hierarchy Process (AHP) to derive weighted influences of key geomorphological, environmental, and anthropogenic factors, including elevation, slope, rainfall intensity, land surface temperature, soil type, vegetation cover, drainage density, and proximity to rivers and roads. Susceptibility maps were generated and classified into five risk categories. The results demonstrate pervasive exposure, with informal settlements predominantly falling within moderate to high susceptibility zones for all hazards: 65.5% and 31.61% of land area exhibit moderate and high flood susceptibility, respectively; 55.58% and 44.17% show moderate and high fire susceptibility; and 67.62% and 29.29% fall within moderate and high landslide susceptibility. These overlapping hazards underscore systemic vulnerability driven by settlement expansion into steep terrain, wetlands, and floodplains. The findings provide crucial spatial intelligence for integrated planning and prioritised disaster risk reduction, highlighting the need for proactive interventions that strengthen resilience and address underlying vulnerability in eThekwini's informal settlements.