Enumeration of total and fecal coliform bacteria in drinking water of Khairpur Sindh

ABSTRACT

The number and range of total coliform and fecal coliform bacteria were analyzed in the drinking water of Khairpur city to determine the quality of the water supplied to the residents of the city. The bacteriological study was carried out for indicator organisms i.e total coliform and fecal coliform [E. coli] by membrane filtration methods. A total of 90 samples were collected from three sites, thirty samples each from main reservoir [water works], distribution line and consumer taps [households, hotels and schools]. All samples were found contaminated [100%] with total coliform [TC] as well as fecal colifom [FC] bacteria. The counts were higher than the maximum microbial contaminant level established by World Health Organization [WHO]. The higher densities of bacteria were found in consumer taps [4-4.30 log cfu/100 ml] per 100 ml, followed by distribution line [3.79-4.20] and main reservoir [3-3.94 log cfu] per 100 ml total and fecal coliform. The pH and residual chlorine of water samples were also determined. It was observed that pH was within the limits of WHO standard [6.5-8.5], the residual chlorine was not detected in any sample of drinking water