Background: Globally, 1.1 billion people rely on unsafe drinking water sources from lakes,rnrivers, and open wells. Many studies have confirmed that water related diseases not onlyrnremain a leading cause of morbidity and mortality worldwide but also that the spectrum ofrndisease is expanding and the incidence of many water related microbial diseases arernincreasing. Thus, water becomes contaminated with faecal material due to inadequaternprotection of the source, unhygienic practice of the community at the source and poorrnhousehold handling practices.rnObjectives: The aim of this study was to assess bacteriological quality of drinking water andrnto survey the possible sanitary risk factors at household level in Arba Minch town, SouthernrnEthiopia.rnMethods: A cross- sectional study was carried out in Arba Minch town from November,rn2010 to January, 2011. A total of 126 water samples were collected from main source,rnreservoir, pipe and household water in three rounds to determine bacteriological quality ofrndrinking water. The bacteriological analysis was conducted at Arba Minch RegionalrnLaboratory. Consequently, level of contaminations was determined on the bases of totalrncoliforms and fecal coliforms existence.rnResults: Water analysis of the study area demonstrated that 100% and 55% of householdrnwater samples were contaminated with total and faecal coliform bacteria respectively.rnSimilarly, 10% and 5% of water samples taken from pipes were again contaminated withrntotal and faecal coliform bacteria respectively. But, 100% of water samples taken from bothrnmain source and reservoir were free from any indicator bacteria. Accordingly, 100% of waterrnsamples taken from both main source & reservoir and 95% of water samples taken fromrnpipes meet WHO guidelines. But, 5% of pipes and 100% of household water samples werernfound above the limits of WHO standards set for drinking water quality.rnConclusions: The majority of water samples in the study area were safe for drinking purposernfrom bacteriological point of view. But some water samples taken from pipes and almost allrnwater samples taken from households were not recommended for drinking purpose.rnTherefore, training of local people to look after the water supply system, extension ofrnhygiene and health education on sanitation could have a notable impact for the provision ofrnsafe water supply at community/household level.