Effectiveness of storage as a point-of-use means of improving the bacteriological quality of drinking water

Abstract

The evaluation of the effectiveness of storage as a point-of-use means for improving the bacteriological quality of drinking water was carried out using a completely randomized block design. Total plate and total coliform counts were enumerated for day 0 -10 samples using Nutrient Agar (NA) and multiple tube techniques respectively. Physicochemical analyses of water samples were carried out using standard procedures including titrimetric methods. Ten bacteria species including Escherichia coli, Bacillus cereus, Citrobacter freundil, Salmonella typhymurium, Pseudomonas aeruginosa, Staphylococcus aureus, Klebsiella pneumoniae, Arizona spp., Proteus vulgaris, Enterobacter aerogenes were isolated from water samples obtained from borehole, well and sachet water samples in the study area. For day zero samples, it was found that the total bacteria counts ranged from 1.01x10² to 4.38 x10² CFU/mL for borehole, 0.57x10² to 2.13x10² CFU/mL for well and 0.54x10² to 0.92x10² CFU/mL for sachet water. A significant reduction in bacteria load was recorded for all samples from day 2 to day 7 when the water samples were monitored over a period of ten days. The results reveal that water storage for 2-7 days is a viable point-of-use method of household level drinking water disinfection. © 2013 International Formulae Group. All rights reserved.

Keywords: Nigerian Institute of Standards, Coliforms, water storage, E.coli.