Evaluation of Water Quality at the Confluence Region of Diyala and Tigris Rivers Based on the Weighted Arithmetic Method

Abstract

This study is conducted to assess the water quality index (WQI) of the Diyala and Tigris River confluence region south of Baghdad (Al-Tuwaitha), based on the Weighted Arithmetic method. Sixteen samples of water were collected from different location in the region through two periods 5/11/2021 and 13/3/2022. Water quality parameters such as (PH, EC, TDS, TH, Ca, Mg, Cl, Turbidity, ALK, SO4, HCO3, Na, and K) were used to evaluate WQI in the study area. The final results showed that the water was not suitable for drinking due to the high concentration of water quality parameters. In the 5 November 2021, the water quality in the study area was classified into (good, poor, very poor, and polluted) where the percentages of the above classes were 4%, 6%, 39%, and 51% respectively, while the percentages for the season 13thMarch 2022 were 1%, 41%, and 58% with very poor, polluted, and very polluted class, respectively. The water was not suitable for drinking due to the high concentration of water quality parameters in most locations in the study area.  There are many sources of pollution in the region that dump their harmful waste into the river, which led to increase the concentrations of water quality parameters in most locations of study area.