Groundwater Quality Assessment for Irrigation in Kirkuk Governorate

All irrigation waters contain some dissolved salts .Dissolved salts are present because some chemical elements have a strong attraction for water and a relatively weak attraction for other elements .The total amount and kinds of salts determine the suitability of the water for irrigation use .Water may contain large amounts of salts that are not suitable for irrigation because of their risks to the soil and crop. The study of groundwater quality is important as one of the main freshwater resources that are used for various purposes, including irrigation of agricultural crops. The study aims to identify the chemical composition of groundwater in Kirkuk Governorate, and evaluate its quality for irrigation purposes. The study area is located between two latitudes (35̊ 23′51″-35̊ 29′ 50″) N and longitude (44̊ 12′47″-44̊ 27′81″)E and has a total area of about (305158.41) hectares .Samples were collected during September (2023), where sixty wells randomly distributed in the study area were selected, many chemical and physical analyzes were conducted, GIS technology was used to perform spatial analysis using (Arc GIS v,10.4.1), the IWQI irrigation water quality index was determined with five parameters, which include electrical conductivity EC, sodium Na, chlorides Cl , bicarbonate HCO3 and Sodium absorption ratio SAR. The values of the irrigation water quality index IWQI ranged between (46.37-86.59).The spatial distribution map of the irrigation water quality index showed that 0.02% of the study area was classified as having excellent restrictions and determinants for irrigation purposes, and that 88.97% of them were classified as having low restrictions and determinants, while 10.98% of them were classified as having moderate restrictions and 0.02% were classified as having high restrictions.