Sura K. Ali
Abstract: Given the importance of the Tigris River in Iraq as a major source for multiple purposes such as drinking water, irrigation, industry and others. Two methods were used for computing water quality index at each province (Nineveh, Baghdad, Maysan) for three years (2013-2015) which are Weighted Arithmetic Water Quality Index method and Bhargava method. Twelve factors have been used to assess the raw water quality of Tigris river by Weighted Arithmetic Water Quality Index methodwhich are alkalinity, total hardness, turbidity, total dissolved solids (TDS), pH, Ec., Cl, Na, Mg, Ca, K and SO4, while six parameters used by using Bhargava method which areT.H., TDS., pH, Ca, Cland SO4.Both WQI methods showed that the water quality of the Tigris River is classified as poor in northern Iraq to very polluted in the south, so it requires specific treatment to make the river water suitable for human use.
Keywords: Water Quality Index, Tigris River, Iraqi Governments, physicochemical characteristic