This study was carried out four main centers in Qalyubia Governorate, Egypt namely Benha, Kafr Shukr, Toukh Qalyub before after treatment process drinking water. Each the four main sites included subsites along the distribution system namely Benha (Mit Asem Benha), Kafr Shukr (Isnit Kafr Shukr), Toukh (Toukh, Al Deir Qaha), Qalyub (Qalama Qalyub). Physical bacteriological examinations were carried out in both main subsites during winter summer 2017-2016. Turbidity pH values were ranged between (1.16-2.60) NTU (7.27-7.87) during two seasons after treatment process, respectively. Additionally, lower values electric conductivity (EC) Total hardness (T.H.) were recorded after treatment than before, the lowest values were observed in Qalyub Benha during summer, respectively. Moreover, total solids (dissolved TDS suspended TSS) values were in permissible limits indicate the efficiency treatment process. Respecting the changes in total bacterial counts in all main subsites under study, higher counts bacteria were observed in samples incubated 37℃ than 22℃ with highest count in Qalyub Toukh, respectively. While Salmonella fecal streptococci counts were reduced with considerable numbers after treatment than before most subsites didn’t record any counts Salmonella during winter. The most prevalence bacteria were isolated testing their susceptibility against antibiotics found one them was multiple antibiotics resistant which finally identified by 16sDNA gene sequencing as Salmonella enterica. Various chlorine concentrations found be efficient against S. enterica 7.0 ppm was the best with save residual chlorine concentration.