Residual chlorine management in water distribution systems using network modelling techniques: case study in Seoul City

Twelve sampling locations in a network from a water treatment plant to consumers' taps were selected for measuring residual chlorine loss, THMs, TOC, etc. and 24 hour sampling in the locations was conducted on a bimonthly basis for one year. Chlorine bulk decay and THM formation tests were carried out by bottle tests under controlled temperatures for three locations: a water treatment plant, a large service reservoir, and a pumping station. Water quality modelling of chlorine loss in the distribution system was performed using data collected in the field study. This study contributed to the improvement of chlorine management in the distribution system by providing information for operators to maintain a minimum level of chlorine residual in a service reservoir.