DBP formation kinetics in a simulated distribution system

Little is known about how the growth of halogenated disinfection by-product s (DBPs) in drinking water is affected by time spent in a distribution syst em. Experiments were performed to compare the rate of trihalomethane and ha loacetic acid production in a simulated pipe environment to that observed f or the same water held in glass bottles, Results showed that although the r ate of chlorine consumption in the pipe was much greater than in the bottle , there was no decrease in the amount of haloacetic acids produced and that trihalomethane levels actually increased by an average of 15%. Separate te sts confirmed that this increase was due to a reservoir of organic precurso r material associated with deposits on the pipe wall. This work suggests th at the rate of DBP production in a distribution system will not necessarily be reduced by increased chlorine consumption due to non-DBP producing reac tions with deposits on the pipe wall. (C) 2001 Elsevier Science Ltd. All ri ghts reserved.