AWWA WQTC69232

The City of Kamloops, British Columbia, recently upgraded its drinking water treatment system to include coagulation, flocculation, and membrane filtration (i.e., ultrafiltration) treatment processes. The objective of this study was to determine if implementation of the membrane treatment facility would reduce the formation of disinfection byproducts (DBPs) within the distribution system. Phase I of the study investigated trihalomethane (THM) and haloacetic acid (HAA) formation in two sections of the distribution system, one section that received water treated by coagulation / flocculation / ultrafiltration / chlorination, and one section that received the same source water treated only by chlorination. Phase II of the study characterized THM and HAA formation using a bench scale flow-through material-specific simulated distribution system (MS-SDS), made from pipe material resurrected from the City of Kamloops distribution system. The results of the present study showed that implementation of the membrane treatment facility did not significantly reduce THM or HAA formation in the distribution system. Further analysis revealed that the THM and HAA precursors in the source water were relatively small and predominantly hydrophilic. Small and hydrophilic DBP precursors typically cannot be removed by coagulation / flocculation / ultrafiltration treatment processes. Includes 7 references, figures.