The town of Parys, situated within the Ngwathe Local Municipality in South Africa’s Free State Province, has recently faced significant challenges related to drinking water quality and supply. Incidents of brown, turbid water emerging from household taps have raised public health concerns and pointed to deteriorating raw water sources primarily the Vaal River heavily impacted by agricultural runoff, domestic wastewater, and industrial discharges. This study assessed the efficacy of local drinking water treatment plants by analysing the physico-chemical and microbial quality of water at various stages: raw water intake, throughout treatment, and at the distribution endpoint. Water samples were collected from the Vaal River, three municipal treatment plants, and a final distribution point at the local police station. Parameters measured included pH, total dissolved solids (TDS), electrical conductivity (EC), turbidity, dissolved oxygen (DO), and bacteriological contaminants, using both in-situ and laboratory methods in accordance with standard protocols. The results indicated that most physico-chemical parameters complied with (SANS 241, 2015) standards, with pH ranging from 7.39 ± 0.62 to 7.45 ± 0.22, TDS from 271 ± 54.1 mg/L to 234 ± 17.99 mg/L, EC at 70 ± 57.3 µS/cm, and DO from 4.53 ± 0.69 mg/L to 4.88 ± 1.39 mg/L. However, turbidity exceeded permissible limits, particularly in the wet season (13.5 ± 4.0 NTU). Bacteriological analysis revealed high contamination levels in raw water, with E. coli, heterotrophic plate count, faecal coliforms, and total coliforms recorded at (75 CFU/100 ml, 450 CFU/1 ml, 58 CFU/100 ml, 320 CFU/100 ml) respectively. Post-treatment samples showed complete removal or inactivation of microbial contaminants, indicating effective disinfection processes. The study concludes that while the water treatment plants in Parys are effective in microbial decontamination, they are inadequate in controlling turbidity, particularly during the rainy season. To address these deficiencies, the study recommends upgrading filtration infrastructure, enhancing the frequency and scope of water quality monitoring, and promoting community engagement in water conservation and pollution prevention initiatives. These actions are vital for ensuring the long-term safety and resilience of the municipal water supply.