Assessing the vulnerability of groundwater to pollution using the SEEPAGE model
MetadataShow full item record
It is estimated that about 80% or more of the low-income peri-urban population in developing countries is currently using groundwater for drinking water purposes (Croni et al., 2006). Urban groundwater quality in these peri-urban and urban settlements is, therefore, an issue of increasing concern due to the high rates of contamination generation per unit area and limited waste management systems (Pegram et al., 1999). This research aims at evaluating the level of groundwater vulnerability to pollution in Jinja district and also identify areas in Jinja where groundwater vulnerability to pollution is most using the SEEPAGE model. In the analysis, the vulnerability index is calculated by considering different hydrogeological parameters such as water table depth, topography/soil slope, vadose zone material, aquifer material, soil depth, and attenuation potential. All parameters for this study have been prepared, classified, weighted, and integrated into the Geographic Information System (GIS) environment. The SEEPAGE vulnerability index values ranged from 120 to 577. Areas with low vulnerability to pollution have an index ranging from 120 to 272, covering about 46% of the district; those with moderate vulnerability ranged from 272 to 424, covering about 43% of the district while those with high vulnerability ranged from 424 to 577 covering about 11% of the district. The results show that Jinja’s largest area lies in the low vulnerability zone hence a low potential of pollution of groundwater. The single parameter sensitivity analysis indicated that depth to water table has the most significant influence on the vulnerability index, with an average weight of 31% against the theoretical weight of 25%. The slope has the least influence on the vulnerability index with an average weight of 12% against the theoretical weight of 10%. This study recommends the implementation of environmental management decisions aimed at mitigating the threat of pollutants on groundwater. The research implores that this model can, therefore, be an effective tool for local authorities in groundwater asset planning and preservation and formulation of efficient groundwater management strategies.