This study analyzed the organic distribution characteristics of original and treated water and their impacts on drinking water quality using a conventional water treatment process in the typical water supply sources for towns in the southwest hilly area of China. The results showed that the water supply source in this area is micro-polluted water. Dissolved organics of low molecular weight accounted for the great majority of the organics, with the proportion ranging from 50% to 80%. There were 53 kinds and 14 classes of organics, including alkanes, esters, phenolic compounds, and benzenes, with the proportion from 80% to 90%. The amounts of organic acid, alkene, alcohols, and aldehyde were small, while the amounts of dichloromethane, phenol, and dibutyl-phthalate were relatively high. Herbicides, food additives, and antibiotics were detected, such as terbuthylazine, 2,6-di-tert-butyl-p-cresol, and nalidixic acid. The conventional water treatment process could efficiently remove the compounds with molecular weights higher than 10×103 and organic acid; however, it was limited greatly in its removal of alkanes, esters, phenolic compounds, and benzenes.
Keywords: conventional water treatment process; distribution characteristics; drinking source; organics; southwest hilly area; water quality.