The objective of this study was to determine the bacterial contaminations in drinking water samples collected form some rural habitations of northern Rajasthan, India. A total of ten bacterial species: Escherichia coli, Pseudomonas aeruginosa, Enterobacter aerogenes, Klebsiella sp, Proteus vulgaris, Alcaligenes faecalis, Bacillus cereus, Staphylococcus aureus, Streptococcus lactis and Micrococcus luteum were identified form drinking water samples. The bacteria belonging to the family enterobacteriaceae (coliforms) showed the maximum occurrences in water samples. The total coliforms count, i.e. TTC\documentclass[12pt]{minimal}
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\begin{document}$^{\it m}$\end{document} (m = MPN index/ 100 ml) in drinking water samples was in the ranges of 25 TTCm (village Naiwala)–41 TTCm (village Meharwala). The data suggested that the drinking water quality deterioration in rural habitations of this region was due to poor sanitation and unawareness about personal hygienic practices. The occurrences some pathogenic bacteria in drinking water may increase the risks of water-related diseases and health problems in local residents.