Water Quality Testing: pH, Turbidity & Chlorine Levels Explained

South Korea’s Wonju city is reporting consistent monitoring of tap water quality, with recent data released on February 13, 2026, detailing levels of turbidity, residual chlorine, and pH.

According to data published by the Wonju City Upper and Lower Sewage Treatment Plant, turbidity levels are consistently maintained at 0.5 NTU or below, despite potentially rising to thousands of NTU during heavy rainfall due to soil runoff. Treatment processes are employed to ensure compliance with the standard.

The city measures water’s acidity and alkalinity through pH levels, reporting a range of 7.5 to 7.9 in recent tests. The acceptable range for pH in Wonju’s water supply is 5.8 to 8.5, with values above 7 considered alkaline and below 7 considered acidic.

Residual chlorine levels, crucial for disinfection, are currently measured at 0.94 ppm at the Wonju Water Purification Plant and 0.88 ppm at the Sinlim Water Purification Plant. The city maintains residual chlorine levels between 0.1 and 4.0 ppm to ensure ongoing sterilization, with a target of at least 0.1 ppm at the tap.

The city’s water quality monitoring includes assessments of taste, odor, and color, all currently reported as within acceptable limits – described as tasteless, odorless, and with a color level of 5 degrees or less. These parameters are considered indicators of water clarity and overall quality.

South Korea’s regulations, outlined in the enforcement rules of the Water Supply Act, mandate continuous monitoring of residual disinfectant concentrations. Measurements of pH and water temperature are required at least once daily, with samples collected from the outlet of the water purification plant.

The Wonju city government publishes real-time water quality data, noting that continuous measurement devices may occasionally display “under inspection” status during maintenance and cleaning.