Coliform contamination as an indicator for potability of different drinking water sources in and around the Nainital City, Western Himalaya, Uttarakhand

摘要

Based on the presence or absence of indicator bacteria i.e., Escherichia coli, drinking water quality supply of Nainital city was investigated from January to December in 2018. The potability assessments of 28 water samples, collected aseptically in sterilized container from treated and untreated water sources, were carried out by determining total plate count and total coliform bacteria count. During the present study, treated water samples were found most suitable for drinking when compared with the samples of untreated as per defined standards of potability by World Health Organization (WHO). The antimicrobial resistance among confirmed E. coli isolates from water samples was also determined by disk diffusion method. All isolates of E. coli were found resistant against Cefotaxime and Penicillin while antibiotics such as Gentamycin and Norfloxacin showed highest susceptibility for isolates investigated in the present study. It is recommended that the current situation of untreated water sources is degrading for drinking purpose and thus, requires an immediate action towards improvement of their quality for the welfare of the residing people. Safe and pure drinking water should also be provided by authorities and municipal corporations to entire population of Nainital City (Uttarakhand, India).