The promising study aimed to periodically monitor the environmental certainty of the Tigris River water and its suitability for irrigation using the water pollution index model in Mosul City, Northern Iraq. The different identified sites were five points, starting from the city entrance of Mosul (Mushairfa area) to the Albusief area where the river leaves the city. The collection of water samples occurred during the drought season (five replicates for each site) using clean polyphthalate containers for conducting physicochemical tests and calculating the different parameters related to irrigation. These include sodium adsorption ratio (SAR), residual sodium carbonate (RSC), permeability index (PI), Kelly’s ratio (KR), sodium percentage (Na %), magnesium adsorption ratio (MAR), and potential salinity (PS). The mathematical model application evaluated the water quality for irrigation purposes. The results indicated that the qualitative characteristics did not exceed the permissible limits for irrigation. However, a relative increase emerged in the values of electrical conductivity, potential salinity, permeability coefficient, and magnesium adsorption rate, among others, with the river flow in the city. Fortunately, the Tigris River water has better quality for irrigation, and as per the irrigation water quality index (IWQI), the values ranged from 0.3164 to 0.3566.
Irrigation water, water quality, Tigris River, water pollution index (WPI), pollution load
A relative increase was evident in bicarbonate ions to reach the highest value (2.64 meq.l-1). The Na (%), KR, and SAR measurements (3.99, 0.041, and 0.11, respectively) were necessary to determine the possibility of using water for irrigation.