This study is principally aimed at the exploration of the bacterial contaminants that are prevalent in the drinking water of different reservoirs in Mahabubnagar, TS, India, along with cost-effective water treatment using palatable leaves of Mentha piperita. Water samples from three different reservoirs of Palamuru, namely, Ramanpadu reservoir (RPR), Koilsagar reservoir (KSR) and Jurala reservoir (JUR), were collected and bacteriological and chemical parameters were assessed. Colony forming units (CFU) were determined by plate culture method using different media. The bacterial diversity concomitant with the three different reservoirs was examined and compared using a molecular approach coalescing fingerprinting by denaturing gradient gel electrophoresis (DGGE). Overall, 37 16S rDNA sequences were obtained. The sequencing dominant bands validated that the major phylogenetic groups identified by DGGE belonged to Bacillus, Brevibacillus, Exiguobacterium, Gammaproteobacteria, Acinetobacter sp. and some uncultured or unidentified bacteria. At household level, incubation of potable water with pudina leaves decreased the bacterial contamination showing its anti-bacterial effect and proving it to be an easy method to impede bacterial contamination in potable water.