ABSTRACT
The study was carried out to investigate the impact of close proximity of septic tanks to borehole water in Ovia North-East L.G.A in Benin city, Edo state, Nigeria. Analysis of water samples from designated areas was carried out for 3 months (April, May and July, 2018). The research areas were Iguosa and Isiohor both in Ovia North-East L.G.A in Benin city and the University of Benin water board as a control station. Four houses from these areas were selected. The location of the boreholes and distance from septic tanks were determined using a Global positioning system (GPS) device and a measuring tape respectively. The water samples from these houses were analysed for both physicochemical and bacteriological properties, they include; pH, conductivity, turbidity, suspended solids, alkalinity, chloride, phosphate, sulphate, nitrate, ammonium, dissolved oxygen (DO), biochemical oxygen demand (BOD), Total coliform count and Faecal coliform count. The results across the stations for the three months sampled had values ranging from 5.12-5.75 (pH), 11.7-26.7 (conductivity), 0-.033 (turbidity), 0-0.17 (suspended solids), 4.7-6.3 (alkalinity), 10.59-12.94 (chloride), 0.093-0.12 (phosphate), 1.3-2 (sulphate), 2.48-2.9 (nitrate), 3.03-3.53 (ammonium), 7.3-8.05 (DO), 2.65-3.1 (BOD), 43.3-1560cfu/100ml (Total coliform count), 0cfu/100ml (Escherichia. coli) and 0cfu/100ml (Streptococcus Faecalis). The presence of total coliform count in all the stations indicated faecal contamination of water. Also, from correlation analysis carried out, result showed increase in bacteria load with decreasing distance. The study recommends the treatment of water before consumption and the need to consider distance of septic tanks to boreholes when acquiring or building a house.
