Groundwater Vulnerability Assessment using Drastic Index and GIS in Kumasi Metropolitan Assembly, Ghana.


  • Anthony Ewusi Geological Engineering Department University of Mines and Technology Tarkwa


DRASTIC, Groundwater, Vulnerability


The assessment of groundwater vulnerability               to contamination has become an important element for landuse planning and groundwater resource management. The study aims at estimating groundwater vulnerability using an integration of Geographic Information System (GIS) and DRASTIC method in Kumasi Metropolitan Area (KMA). The groundwater vulnerability map was prepared using index and overlay analysis with the aid of Arc GIS 10. The DRASTIC Index (DI) computed ranged between 70 and 164 as the lowest and highest contamination potential respectively. The eastern and western flanks and north-west tip of KMA underlained by the granites which bear water due to the combined effect of weathering and fracturing were dominated by "Very High", "High" and "Moderate" vulnerability. The "Low" and "Very Low" vulnerability are located at the northern, central and southern parts of KMA underlained by phyllites. These suggest that boreholes located in the Birimian metasedimentary units mostly phyllites would be less likely to be vulnerable to contamination than those located in the intrusive rocks dominated by the granites.


Author Biography

Anthony Ewusi, Geological Engineering Department University of Mines and Technology Tarkwa



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Geological Eng. Article