Microbial quality of water in Barekese reservoir and feeder streams in Ghana: Fid-Bau Portal

Microbial quality of water in Barekese reservoir and feeder streams in Ghana

Kumasi, Tyhra Carolyn / Obiri‐Danso, Kwasi / Ephraim, James Hawkins

Concern is growing in Ghana about the high incidence of water‐related diseases and deaths resulting from use of water contaminated with microorganisms. This water often remains unsafe for human consumption because of inadequate decontamination of microbially infected water. Data are presented in this study on the microbial quality of Barekese reservoir, which is the main drinking water reservoir for the city of Kumasi and its environs (population = 2, 5 million), and nine feeder streams in its catchment. Water samples were collected from 13 sampling sites and analysed for Escherichia coli, total and faecal coliforms. Furthermore, 18 faecal coliform isolates were randomly selected from all sampling sites and confirmed as E. coli using Analytical Profile Index 20E system. Escherichia coli, total and faecal coliforms were enumerated using the most probable number method. Mean bacterial indicator numbers from all sampling sites ranged from 1.45 × 10⁴ to 9.50 × 10⁷ 100 mL⁻¹ for total coliforms, 1.60 × 10³ to 9.00 × 10⁵ 100 mL⁻¹ for faecal coliforms and 1.50 × 10¹ to 9.50 × 10³ 100 mL⁻¹ for E. coli. Indicator numbers exceeded the World Health Organization (0.100 mL⁻¹) for E. coli and Ghana Water Resources Commission‐Target Water Quality Range of 5–100 100 mL⁻¹ for total coliforms and 0.100 mL⁻¹ for faecal coliforms in water used for domestic purposes. The identified isolates in Barekese Reservoir and its feeder streams belonged to Serratia, Enterobacter, Citrobacter, Salmonella and Klebsiella genera. Bacterial numbers were significantly (P < 0.05) higher in the feeder streams, compared with Barekese Reservoir water. This finding indicates the feeder streams pose health risks to local communities that withdraw water from them. The results of this study highlight the urgent need to raise public awareness on the adverse effects of water‐quality degradation through improper waste disposal methods in order to decrease the cost of treating the reservoir water.