Web-based Mapping and Assessment of the Spatial Extent, Intensity and Resilience of Flood Events in Lugbe, Abuja, Nigeria

Abstract

This study evaluates flood spatial extent and intensity in Lugbe, Abuja, using integrated geospatial techniques and rainfall–flood relationship modeling to inform sustainable urban planning. Employing an interdisciplinary design—combining Remote Sensing, GIS, hydrological modeling, and Google Map WebGIS visualization—the research delineates flood-prone zones, quantifies hazards, and examines governance implications. The findings indicate that 34% of Lugbe lies within moderate-to-high hazard zones, with severe areas experiencing flood depths exceeding 1.5m. Vulnerability is heavily concentrated in low-lying drainage corridors and rapidly expanding estates; high-intensity hotspots impact River Park Estate (21.5 ha; 4.48%), Trademore Estate, the Voice of Nigeria axis, and informal settlements near Lugbe Fruit Market, contrasted by low exposure in FHA Capua (1.59 ha; 1.39%). Spatial overlay analysis reveals that 33–36% of local buildings and infrastructure are exposed. Key drivers include high impervious surface coverage (65–75% in built-up estates) and inadequate or blocked drainage infrastructure affecting roughly 40% of mapped corridors. Rainfall modeling indicates that extreme events (>50 mm/day) trigger over 60% of severe floods, and a projected 10% increase in rainfall intensity could boost runoff by 15–20%. Crucially, integrating WebGIS dashboards improved hazard communication by 40–50% and cut emergency response times by up to 45%. The study advocates for immediate drainage remediation, strict enforcement of zoning laws, and a ban on waterway encroachment to mitigate accelerating climate risks.