Applying the sub-index model to evaluate the quality of water for irrigation purposes, a case study: wells water of left side from Mosul city, Iraq

The present study aims to assess the quality of well water in some areas of the left side of Mosul city for irrigation; Water samples were collected from twelve wells scattered in the neighborhoods of Al-Muthana, Al-Zohoor, Al-Siddiq and AlHadba from November 2019 to January 2020 to measure the physical and chemical properties of wells and applying the subindicator model to evaluate the water quality. The results of the study indicated the suitability of well water quality for irrigation, where the WQI values ranged between (34.5-59.8(, which indicates that the water quality from good water type to excellent quality for irrigation, and this relative deterioration is due to the high values of pH, EC25, P. Salinity, Mg Hazard and HCO3 ions as well as the effect of the relative weight (Wi) that was reflected in the values of (IWQI) and confirmed by the effective weight values (EWi) for each parameter that ranged between (15.0-22.8), (16.1-21.3), (27.5-34.5), (11.9-15.9) and (7.239.47), consecutive. Keyword: Groundwater quality, IWQI, Irrigation water indexes