Abstract:
Waterborne diseases are a global problem that causes more than 2.2 million deaths annually.
Therefore, the present study was focused on microbiological contamination of both ground and
surface water by means of total coliform, Escherichia coli (E. coli), Salmonella spp., Shigella spp. and
Campylobacter spp. Seventy two groundwater and 45 surface water sampling locations were selected to
collect water from the head, transitional and meandering regions of the Kelani River Basin for a period
of one year (both dry and wet seasons). The results of the study revealed that the entire Kelani River
basin was contaminated with total coliform and E. coli bacteria and almost all the sampling locations
exceed Sri Lanka Standards Institute (SLSI) guideline value given for drinking water (0 CFU/100 mL).
Further, in groundwater, 17 locations were positive for Salmonella spp., whereas only 2 locations were
positive for Campylobacter spp. In surface water, 26 and three sampling locations were positive for
Salmonella spp. and Campylobacter spp., respectively. In this study, 23 di erent human pathogenic
serovars were isolated and the Salmonella enterica serovar Kentucky was identified as the commonest
type. Thus, the result of the study revealed that the consumption of raw water from the Kelani River
Basin is unsafe and possible to cause gastrointestinal diseases.
