Effectiveness of chlorine treatment on physico-chemical characteristics of water supplies for Zakho city/kurdistan of Iraq

The present work was undertaken to investigate the drinking water quality of Zakho city after adding chlorine (as an efficient disinfectant), and assess the water quality of Little Khabur River (before adding chlorine). Also a systematic study has been carried out to assess the water quality of Zakho city after distribution (at the consumer tap). Water was analyzed during rainy season for 2014 and during all seasons of 2015 to determine its quality using standard methods. The aim was to find how the addition of chlorine could affect the physical and chemical properties of water for Zakho city. Quantification of chlorine residual, pH, turbidity, etc. was performed. Each physico-chemical parameters (pH, dissolved oxygen, COD, BOD, total alkalinity, hardness, turbidity, etc.) was compared with the standard desirable limit of that parameter in river water (or drinking water) as prescribed by WHO. pH generally ranged from 7.02 to 7.30; conductivity fluctuated from 359 to 374 μS/cm; turbidity varied from 0.34 to 2.79 NTU; and TDS values were found to be ranging between 180 and 187 mg/l. Chlorine normally added to public water supplies to kill disease-causing bacteria that the water or its transport pipes might contain. The value of total chlorine was found to be 0.86 to1.7 mg/l.