Determining the occurrence of potential groundwater zones using integrated hydro-geomorphic parameters, GIS and remote sensing in Enugu State, Southeastern, Nigeria

In many parts of Nigeria, water resource is scarce, and where available, determining their abundance is difficult. In the present paper, various groundwater potential zones for the evaluation of groundwater availability in Enugu State have been delineated using remote sensing and GIS techniques. The satellite images and conventional data obtained from US Geological Survey, World Soil Resources Office in Cooperation with Land and Water Development Division/FAO and Nigerian Geological Survey Agency are used to prepare the thematic layers viz. drainage density, geomorphology, slope, landcover/land use, soil, geology, rainfall and lineament density were converted to raster data adopting feature to raster converter device in ArcGIS. The raster maps of abovementioned factors are assigned a definite score and weight computed from multi-influencing factor approach. Additionally, each weighted thematic layer is statistically computed to generate groundwater potential zones map of the study area. The groundwater potential zones thus obtained were divided into four categories, viz., super-abundant, moderately abundant, abundant and scarce zones. The groundwater resources map demonstrates that the study area is dominated by abundant and scarce groundwater potential zones which covers surface area of about 6073.44 km2 (73.27%) of the study area while the remaining 2294.98 km2 (26.73%) are dominated by super-abundant and moderately abundant groundwater potentials. However, the result validation with boreholes/wells yield data collected from the study area showed good correlations with respect to groundwater potential zones map. It is concluded that the use of hydro-geomorphic approach is very efficient for the determination of groundwater potential zones.