Mapping Fluvial Flood and Environmental Risks in Ngaoundéré -Vina’s Riparian Zones Using Proximity-Based Analysis, Adamawa, Cameroon

Riverine flooding, intensified by climate change and rapid urbanisation, threatens Ngaoundéré-Vina, Adamawa, Cameroon, particularly in its riparian zones. The study aimed at quantifying riverine flood exposure at the building parcel scale while identifying contamination hotspots where 73% of solid waste sites and 69% of potable water wells occupy flood-prone zones. Employing a Proximity-Based Flood Hazard Exposure Analysis (PBHEA) framework, the methodology integrated geospatial data building footprints, historical flood extents, and topographic variables (elevation, slope) with Geographic Information Systems (GIS) and Multi-Criteria Decision Analysis (AHP-MCDA) to model flood probability and proximity risk. Results indicate that 42.51% of the study area lies within high to very high flood susceptibility zones, with low-lying settlements and impermeable surfaces amplifying exposure. Flood-induced contamination from waste sites threatens groundwater, elevating public health risks (waterborne diseases). The high-resolution exposure map, validated with 90% accuracy against 35 historical flood events (2019–2023), pinpoints critical hotspots for targeted interventions like riparian buffer zoning and drainage upgrades. This replicable, cost-efficient approach empowers municipal planners to prioritise flood risk mitigation and enhance urban resilience in data-scarce settings, safeguarding vulnerable communities against escalating fluvial flood hazards.