Flood Risk Assesment of Zaria Metropolis and Environs: A GIS Approach

Abstract

Delineation of flood prone areas within Zaria and environs was carried out. Spatial data such as elevation, slope, wetness and drainage distances was used to delineate flood prone areas. These data were reclassified and weighted using Analytical hierarchy procedue-multi criteria evaluation method. The resulting flood risk map reveals the central and north eastern part of the study area as highest flood risk zones, while the southwestern part of the study area as the lowest flood risk factor. Areas delineated as having very low flood risk account for 28.3% of the study area and covers some 86.88 km2. Areas delineated as having low flood risk accounted for 29.5% of the study area and covers 90.56 km2. Areas depicted as having high flood risk accounted for about 32.1% covering some 98.545 km2. Areas depicted as having very high flood risk accounted for 10% of the study area and covers an area extent of 31.007 km2. Future infrastructural development must be guided by technical reports forecasting high risk, flood prone areas.