The occurrence of haloacetic acids (HAAs) was studied in the drinking water samples from Gharbiya governorate water treatment plants and its water supply network that served more than 5 million people. Drinking water disinfection by-products are formed when a disinfectant reacts with natural organic matter and/or bromide/iodide present in a raw water source.  Trihalomethanes and haloacetic acids are the two most prevalent classes of DBPs and are regulated by the US Environmental Protection Agency as well as being subject to World Health Organization guidelines due to their potential health risk. Drinking water samples were collected from 4 sites monthly over one year (2017-2018). The aims of the present study are to investigate the levels of HAAs in Gharbiya governorate (middle of Delta Egypt) drinking water. monochloroacetic acid ranged from 6.8 to 32.5 µg/L, dichloroacetic acid ranged from 9.8 to 43.7 µg/L, and the trichloroacetic acid ranged from 6.5 to 31.8 µg/L, the minimum values observed during winter 2018 and the maximum value observed during summer 2017., The HAAs species values were complying with the Egyptian standard (Ministerial Decree No.458/2007) and as well as WHO 2012) standards for drinking water.

Keyword(s): Haloacetic acids, DPBs, Gharbiya Governorate, Egypt, Environment, Pollution, Disinfection,