Evaluation of Groundwater Chemistry in parts of Abuja, Nigeria using Factor Analysis and Water Quality Index

Abstract

Water is a universal solvent and natural resource tapped by man, animal and plants to meet their need on earth, either in vapour, liquid or solid form. Due to inadequate supply of pipe-borne water, many house-holds in Abuja, Nigeria’s Federal Capital Territory, depend on boreholes and hand-dug wells for their daily water needs, hence the need to ascertain the quality status of groundwater in the area. A total of sixty (60) sets of groundwater samples were collected from two field sampling periods of dry and rainy seasons between the months of April, 2009 and February, 2010. The samples were analyzed using Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES) in Actlabs, Canada. The result of the laboratory analysis was transformed using water quality index and factor analysis. Six factors were identified which accounts for 76.70% of the total variance for dry season and 88.53% of the total variance for rainy season. This implies that the groundwater systems in the area are contaminated through six possible sources. The contaminants are from natural sources such as bedrock dissolution and weathering processes while the remaining factors are attributed to anthropogenic activities arising from urbanization such as leachate from dumpsites, soakaways and agro-chemicals. The water quality index shows that the water in the area range from good to poor. Due to food insecurity, undeveloped plots of land are converted to farmland and the agro-chemicals applied on the soils over time infiltrate into the shallow water table in the area. The suggested geogenic and or anthropogenic factors may be responsible for the modification of the groundwater chemistry in the area. Public enlightenment on the good hygiene and danger of groundwater contamination is recommended.