Hydrochemical Assessment and Groundwater Quality of Eastern and Western Catchments of Erbil City, Northern Iraq

Abstract

This study aims to determine the physiochemical properties of water quality which is essential for assessing its suitability for various purposes, including livestock, building, agricultural and drinking water supplies.Water well samples were collected from different wells during two periods, the first period is considered a minimum recharge period (drought) in November 2021 and the second period is considered a maximum recharge period (wet) in May 2022; 36 samples (18 from the eastern part, 18 from the western part) for each period.Water sample collections were made for the purpose of hydrochemical study which involved the analysis of major cations, anions, the salinity, temperature, electrical conductivity, and pH. The accuracy of the water sample analysis shows that all of the samples are useful for the hydrochemical interpretation. Aquifer sediments and abundant soils are considered to be the major sources of cations and anions, whereas the fertilizers, municipal wastewater and irrigation-return flows are additional contributors of Mg2+, Na+, K+, Cl-, SO42- ions. The concentration of major ions decreases slightly in the wet season due to excess rainfall which normally dilutes dissolved elements. Generally, the concentration of physiochemical parameters, cations, and anions in the eastern part is lower than in the western part because the eastern part is considered a recharge zone of the basin. The soil formation and depth of wells could also be a significant factor.