Flood Vulnerability Assessment of Afikpo South Local Government Area, Ebonyi State, Nigeria

Abstract

The study was conducted in Afikpo South Local Government covering a total area of 331.5km2. Remote sensing and Geographic Information System (GIS) were integrated with multicriteria analysis to delineate the flood vulnerable areas. Seven criteria were considered; rainfall, runoff, slope, distance to drainage, drainage density, landuse and landcover, and soil. The various criteria were fit into fuzzy membership classes based on their effect in causing flood. The fuzzy members of all criteria were then overlaid to generate the flood vulnerability map. The result of the flood vulnerability map shows that very low vulnerable zones cover 86.7% of the total area, low vulnerable zones cover 1.6% of the total area, moderate vulnerable zones cover 2.17% of the total area, highly vulnerable zones cover 2.3% of the total area while very highly vulnerable zones cover 7.3% of the total area. Built up was used as a measure of the effect of flooding on human lives and properties in Afikpo South Local Government. Built up covers a total area of 38.6km2. Over sixty eight (69.8%) of built up lies in very low vulnerable zone, 3% lies in low vulnerable zone, 3.7% lies in moderate vulnerable zone, 0.6% lies in highly vulnerable zone and 17.9% lies in very highly vulnerable zone. The study provides information on target areas that may be affected by flood in Afikpo South Local Government. This information is useful for decision making on flood early warning and preparedness as well as in mitigation preparedness within Afikpo LGA.