Bacteriological Analysis of Water Tanks in Girls’ Hostels in Joseph Sarwuan Tarka University Makurdi, Benue State

Abstract

This study investigated the bacteriological quality of water stored in girls’ hostel tanks at Joseph Sarwuan Tarka University, Makurdi, Benue State, Nigeria. Water samples were collected from three hostel tanks: Hostel Block A, Hostel Block B, and Zamf Girls Hostel using sterile containers. The samples were serially diluted and inoculated using the pour plate method into Nutrient Agar and MacConkey Agar, then incubated at 37 ºC for 24 hours to determine the total heterotrophic and coliform counts. Distinct colonies were sub-cultured on selective media such as Eosin Methylene Blue Agar, Xylose Lysine Deoxycholate (XLD) Agar, and Mannitol Salt Agar for differential identification. Bacterial isolates were characterized through Gram staining and a series of biochemical tests. Results revealed total heterotrophic bacterial counts ranging from 1.79×10⁴ ± 0.13 cfu/ml to 2.03×10⁴ ± 0.13 cfu/ml, while total coliform counts ranged from 2.53×10³ ± 0.36 cfu/ml to 3.21×10³ ± 0.36 cfu/ml, exceeding WHO and EPA permissible limits. Seven bacterial species were identified: Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella species, Bacillus species, Salmonella species, and Streptococcus species. The presence of coliforms such as Escherichia coli and Salmonella species indicates faecal contamination, while Staphylococcus aureus and Streptococcus species suggest contamination from human handling or poor hygiene. The findings suggest that the hostel water is bacteriologically unsafe for consumption. Regular cleaning, disinfection, and bacteriological monitoring of water storage tanks are therefore essential to ensure water safety and protect the health of hostel students