Assessment on the trihalomethanes formation potential of Tan Hiep Water Treatment Plant

Vu Nha Trang, Lai Duy Phuong, Nguyen Phuoc Dan, Bui Xuan Thanh, Chettiyappan Visvanathan



The quality of raw water of Sai Gon River has been degraded in terms of an increase of pollutants such as organic substances, nitrogen and pathogen due to poor water pollution control of agricultural, industrial and domestic activities in the upstream region. This has resulted in high chlorine consumption of water treatment plants which take raw water from Sai Gon River. The current amounts of chlorine used for pre-chlorination at the Hoa Phu Raw Water Intake and at the receiving box at Tan Hiep Water Treatment Plant are about 1-2 and 2-4 g/m3, respectively. Total organic carbon (TOC) value of raw water ranged from 2.9 – 4.1 mg/L. At high concentration of total chlorine coupled with high value of TOC, thus disinfection by-products (DBPs) in the treated water may be formed before entering the distribution network. This study focused on assessment of THM formation potential at unit operations of Tan Hiep Water Treatment Plant. The average total THMs at the sedimentation tank and after disinfection were about 76.7 and 155.8 µg/L.


Keywords: Formation potential; Trihalomethane; Natural organic matter; Saigon river water; Water treatment plant