Microbiological Quality Assessment of Groundwater around Industrial Effluent Site of Odonla-A suburb of Ikorodu, Lagos

Abstract

This research work was conducted to determine the faecal contamination level in underground sources of drinking water around an industrial effluent site in Odonla, a suburb of Ikorodu North Local Government of Lagos State, Nigeria. Thirty samples were randomly collected from thirty different locations of groundwater sources which either served domestic or commercial purposes.  Each of the samples was collected at about 100m away from each other and at not more than 300m away from industrial effluent source. Level of faecal contamination using Escherichia coli as indicator organism and physico-chemical properties of the water sources were conducted. The results showed that 20% of the samples collected were below WHO pH standard (6.5-8.5) for drinking water. Although the samples were physically presentable in terms of colour, odour and taste but microbiologically unfit for drinking as the microbial analysis showed that all the collected samples had E. coli content above the specified WHO range (0cfu/ml) with 36.7% having 1-10cfu/ml; 60% having 11-20cfu/ml and 3.3% having 21-30cfu/ml. The waste effluent samples had less Escherichia coli count than 35% of the samples collected near the effluent discharge point indicating possible faecal pollution from other sources.