Assessment of Contamination along the Tigris River from Tharthar-Tigris Canal to Azizziyah, Middle of Iraq

The Tigris River is the second-longest river in Western Asia and runs through heavily populated areas, especially Baghdad city with nearly 8 million inhabitants. water demand at its highest levels, nevertheless discharge has severely declined last decades; combined fact that wastewater quantities are increasing, treatment plants experiencing a deficiency. Four sites were chosen: Tharthar-Tigris Canal which located north part of city, Diyala conjunction site, Al-Azizziyah site south near Kut government, to determine effect decreasing flow on quality identify sources pollution. In this research, used method evaluates concentration contaminants along course source as novelty research. data include River, hydrochemical analysis, such major ions trace elements, biological parameters (BOD5, COD, E. coli bacteria, coliform bacteria MPN/100 mL) contamination indicators. Multivariate statistical techniques (factor analysis) applied evaluate spatial variations, for years 2005 2020, Phreeqc software was assess saturation indices dominant geochemical processes responsible surface quality. minerals gypsum, anhydrite, halite. within permissible limits drinking, except main deterioration factors recognized as: total dissolved solids, fecal BOD5, COD. By applying SPSS program, two identified. first anthropogenic factor discharged into represents 71.27% variance comprised agricultural land sewage water. While second 17.02%, indicated by variables Ca2+, K+, Mg2+, SO42?. This accounts chemical weathering rocky components. It recommended periodic monitoring system needed to. follow up pollution levels conducting seasonal surveys.