The selection of appropriate technological processes for water treatment has a key impact on the qualitative safety of water intended for human consumption. The article analyzes water treatment processes used in a selected Water Treatment Plant (WTP) in terms of surface and ground water treatment. Five-year results of the research are presented on selected physico-chemical and bacteriological parameters of water quality before treatment processes, after individual stages of treatment (settling tanks, DynaSand® filters, ozonation, carbon filters, UV rays and chlorine gas disinfection). The reduction of key pollutants at individual stages of technological processes was calculated. The results of the analyzes demonstrated that the technological processes used in WTP effectively remove turbidity, color, UVA254nm, permanganatate oxygen demand, Fetotal, Mn,