Source to in-house and seasonal contamination of drinking-water quality is a persistent problem in developing countries. This study was conducted in Damot Sore Woreda, Southern Ethiopia to examine physico-chemical and bacteriological quality of drinking water. In this study, four Kebele administrations were selected by purposive sampling technique. Location map and water quality sampling point were prepared using Arc GIS 9.2 software. A total of 55 water samples were taken and examined for physico-chemical and bacteriological parameters;11 from source,11 from household containers,11 from drinking cup,11 for dry and 11 for wet season. One way ANOVA and correlation was employed to see the statistical difference of the variables at 5% significant level and to observe associations of variables. The result of water quality revealed that average value of all selected physico-chemical parameters showed variation from source to storage. Temperature decrease significantly from supplied source to household storage (p = 0.036). However, other parameters showed no significant change from source to storage. Bacteriological parameters showed variation from source to household storage and from storage to point of-use. The concentration of total coliform increases significantly from supplied source to point of use (p = 0.024). The dry and wet season measurement showed that variation in physico-chemical and bacteriological parameters. However, statistically no significant difference was observed between dry and wet season in all parameters studied. The result of water quality test revealed that average values for all selected physico-chemical parameters were found within the acceptable limit of ES and WHO standards, except Temperature and Phosphate. But the result of bacteriological water quality for all sampled sites exceeded to the ES and WHO standards. So, supplied water in the area is bacteriologically contaminated and therefore not suitable for domestic purposes unless treated.
Keywords: water quality, source, storage, point of-use, dry season, wet season and Damot Sore.