A screen showing the chlorine disinfection byproduct (THMs) prediction program developed by the Seoul Water Institute. [Seoul Metropolitan Government]
A screen showing the chlorine disinfection byproduct (THMs) prediction program developed by the Seoul Water Institute. [Seoul Metropolitan Government]

The Seoul Metropolitan Government said Tuesday it has developed its own program to predict the generation of trihalomethanes, a disinfection byproduct produced during tap water treatment.

In summer, when monsoon rains and heat waves arrive, rising water temperatures and rainfall increase the volatility of raw water quality. The city said it expects the program to enable more systematic water quality management during those months.

According to the city, tap water production involves a chlorine disinfection process to eliminate pathogenic microorganisms. When chlorine reacts with organic matter in the water, trihalomethanes form. Because concentrations above a certain level can be harmful to human health, continuous monitoring of their generation is necessary.

The city said management is also needed because chlorine dosage and process operating methods vary across purification centers depending on the characteristics of the raw water and operating conditions at each facility.

The Seoul Water Institute developed the program using five years of operational data from 2020 to 2024 at two purification centers. Researchers examined key factors affecting trihalomethane generation — including raw water quality, chlorine dosage and water temperature — and optimized a predictive formula.

Users can enter conditions such as raw water quality and chemical dosage into the program to predict trihalomethane generation at each stage of the water treatment process.

The tool helps operators review in advance how trihalomethane concentrations would change under varying conditions, allowing more precise adjustments to chlorine dosage and process settings.

The city has distributed the program to two centers, including the Gangbuk Arisu Water Purification Center, and is verifying the operational results. Based on those findings, it plans to refine the program and expand distribution to all purification centers by next year.

Yun Hui-cheon, director of the Seoul Water Institute, said the program is significant because it was developed to put research findings to practical use in purification center operations.


ken@heraldcorp.com