Bacterial Contamination of Drinking Wells in Makurdi Metropolis

Abstract

This study was carried out to assess the bacterial contamination of drinking wells in Makurdi metropolis. Fifteen (15) untreated water samples, five (5) each were collected from wells in High Level, Wurukum and Wadata areas for physicochemical and bacteriological analysis was done using pour plating and the bacteriological quality was assessed by measuring the total viable, total coliform and fecal coliform counts of bacteria in the samples using Mac Conkey agar and Nutrient agar. The results of the analysis showed that the pH ranged from 6.70 ± 0.16 to 7.40± 0.87, the temperature levels ranged from 28.72 ± 0.04 to 28.87 ±0.05; biological oxygen demand values ranged from 0.02 ±0.04 to 0.02 ± 0.41; the dissolved oxygen values ranged from 1.50 ±0.16 to 170 ± 0.14 while the Electrical conductivity values ranged from 599.20 ±88.98 to 1582.80±199. The results also showed the total viable count, total coliform count and fecal coliform counts ranging from 75.80±16.01cfu/ml to 117.40±34.45cfu/ml; 5.60±5.13cfu/ml to 6.60±6.88cfu/ml and 0.40±0.89cfu/ml to 4.20±3.77cfu/ml respectively. The total viable counts ranged from 75.80±16.01 to 117.40±34.4 (Wadata having the highest and Wurukum having the least), the total coliform counts ranged from 5.60±2.61 to 6.60±6.88 while the fecal coliform count ranged from 0.40±0.89 to 4.20±3.77. The variation in Total Viable Count (TVC) across locations could be as a result of localized factors influencing microbial populations and geographical differences such as land use, anthropogenic activities, and environmental conditions. The bacterial isolates were Bacillus, Escherichia coli, Klebsiella spp, Proteus spp, Enterobacter spp, and Staphylococcus spp. The frequency of occurrence and prevalence percentages of the bacteria isolated from the well water samples show that Klebsiella spp had the highest percentage (23.33%) while Enterobacter spp and Escherichia coli had the least prevalence percentage, representing 10.00% each. Overall, High Level had the highest contamination rate, accounting for 43.33% of the total contamination while Wurukum had the least contamination, representing 23.33% of the total contamination. The distribution patterns of bacterial isolates among the studied locations illuminate discernible trends. The prevalence of pathogenic bacteria in well water sources could be possibly linked to higher urbanization and population density, highlighting the dynamic and site-specific nature of microbial communities. The study highlights the importance of using specific plans to manage water quality. These plans should take into account the special features of each area.