Assessment and delineation of groundwater potential zones using integrated geospatial techniques and analytic hierarchy process

Abstract

Hydrogeologists and other allied professionals involved in the exploration and management of water resources have benefited greatly from the integration of geospatial techniques and remote sensing (RS) applications for identifying prospective or possible groundwater availability zones. This method is progressively becoming a viable alternative to the traditional geophysical survey for groundwater (GW) exploration, which is costly, time-consuming, and labour-intensive. This research explored the applicability of integrating RS, geospatial technologies and multi-criteria decision analysis (MCDA) for mapping and classifying GW potential zones in Bosso Local Government Area of Niger State in Northern-Nigeria. Five thematic maps were produced which represent the factors that influence and control the occurrence and transportation of GW. These factors are geology, lineament density, slope, land use and land cover, and drainage density. Normalized weights were assigned to these factors using analytic hierarchy process (AHP) based on their relative influence on occurrence and transportation of GW. Weighted overlay was implemented in a GIS environment to model the MCDA resulting to a GW potential map (GWPM). The produced GWPM was classified into four classes: ‘Very low’, ‘Low’, ‘Moderate’, and ‘High’ representing 3, 1, 85 and 11% of the total study area, respectively. The obtained result was validated using datasets obtained via hydrogeophysical techniques (vertical electrical sounding), and the result shows 68% positive correlation with the integrated remote sensing approach. The generated GWPM is recommended as an essential tool for water resource developers, and government agencies in charge of sourcing and distributing potable water resource in the study area.