Geoinformatics and Analytic Hierarchy Process (AHP) in modelling groundwater potential in Obudu Plateau, Southeastern Nigeria Bamenda Massif

Abstract

Water is a vital resource used in effective sanitation, hygiene, drinking and agricultural uses. This study was in Obudu Plateau covering an area of 3,053.08km². Analysis of remote sensing, geographic information system (GIS), and global positioning system (GPS) data obtained from satellite imageries and digital elevation model (DEM) assessed groundwater potential. The model was validated using borehole data in the area. Thematic layers of geology, lineament density, slope, geomorphology, land use and land cover and drainage density were integrated using GIS software. Multicriteria evaluation of the layers was by analytic hierarchy process (AHP). Pairwise comparison matrix shows consistency the consistency ratio is 0.07 or 7%. This shows the comparison of groundwater controlling factors is within acceptable limit of consistency. Overlay analysis produced groundwater potential map classified into five zones of very high 2.66% (81.31km²), high 6.92% (211.38km²) very low 9.60% (292.69km²), moderate 46.95% (1,433.46 km²) and low 33.87% (1,034.23km²). Structural geological setting determines largely the suitability of an area to groundwater occurrence. Overlaying each thematic layer with lineament density map produced a more credible groundwater potential model compared to preceding related works. This method is suitable for both local and regional groundwater development.