<![CDATA[Bacterial resistance to water purification processes reflects the capacity of microorganisms to adapt to changing environments, necessitating a critical re-evaluation of bacterial resistance patterns in drinking water. Although sachet drinking water often contains detectable microbial loads, the potential role of inadequate disinfection procedures within quality control units is frequently overlooked. This study investigated ten samples from each of four popular brands of sachet drinking water (Teenerx, Danchiz, Wisdom, and Fountino table water) purchased within the study area in Nigeria. Isolation and enumeration of bacteria were performed using the spread plate technique, while morphological and biochemical characterizations were conducted to identify specific bacterial genera. The results revealed detectable concentrations of non-fastidious bacteria across the samples, with mean total viable counts of 1.0 x 102, 7.0 x 101, and 4.5 x 102 CFU/mL for Teenerx, Danchiz, and Fountino table water, respectively, showing statistically significant differences (p < 0.05). The isolated bacteria were identified as Staphylococcus aureus, Staphylococcus epidermidis, and Proteus spp., all of which exhibited sensitivity to chlorine alongside distinct biofilm-forming features. While chlorine susceptibility indicates effective protein denaturation, the expression of biofilm structures serves as a cellular defense mechanism that enhances bacterial persistence in water systems. Although these levels may technically comply with specific baseline colony-forming thresholds, the presence of opportunistic pathogens poses potential public health concerns that warrant strict regulatory oversight. Therefore, this study recommends a comprehensive reassessment of bacterial resistance traits and optimization of disinfection protocols in sachet water production to ensure consumer safety.]]>
