Source identification and apportionment of pollution sources to groundwater quality in major cities in Southwest, Nigeria

Groundwater in form of hand-dug wells and boreholes serves as the main source of drinking water to the people of south-western Nigeria. Contamination of this resource has been linked to many ambiguous pollution sources. The aim of this paper is to identify and apportion sources of pollution to groundwater in five major cities in south-western Nigeria using Principal Components Analysis (PCA). Studies on physico-chemical parameters of groundwater from Abeokuta, Ifo, Sango, Ibadan and Lagos were adopted from published literatures, and evaluated using a SPSS statistical package. PCA revealed factor ranges between four and eight. Sources identified were bedrock weathering/sea water, nutrient, solids, urban/traffic runoff, industry, hardness, faecal pollution, soil leaching, nutrient, salt-water intrusion and leachate.