Samples of water were collected from the Khabur River in Zakho city in Iraqi Kurdistan Region in three seasons, the summer, autumn, and winter of 2021, at three different locations, before arriving at the city, inside the city, and after passing the city, and some Physio-chemical properties of water were determined to evaluate the spatial and seasonal variation effects on the renowned Khabur River properties. The result revealed the dissolved oxygen DO, biological oxygen demand is significantly (p<0.01) influenced by the summer season than autumn and winter, as the high temperature minimizes the dissolvability of oxygen necessary for life in the water, however, the level of BOD in Khabur river in three seasons not exceeded the recommended level of WHO and Iraqi slandered 3 mg/l. The pH of the Khabur River is not significantly affected by seasonal changes, while EC is significantly affected by seasonal variation. The alkalinity of the Khabur River is significantly higher in summer than in autumn and winter, and the opposite of almost all the studied parameters that increased in winter. The river has a total hardness greater than 200 mg/l as well as total calcium and magnesium. Hardness is significantly high in winter, as the dissolution of both Ca and Mg from bedrock and soil is increased by the action of heavy rainfall on the eroded soil. Regarding the spatial variation, the most studied parameters of the Khabur deteriorated when the river enters Zakho city, as approximately all the sewage water of this city is discharged into the river without any proper treatment.

The main objective of the present study is to spatially evaluate the water contamination of Khabur River, before it arrives in Zakho City, inside the city, and after  it leaves the city of Zakho by heavy metals. Also, the seasonal effects of Zakho municipal wastewater discharged in the Khabur River were detected in this study. The results showed that some heavy metals, such as Ni, were not detected in all studied samples in this study due to their low concentration levels. It is indicated that heavy metals are statistically affected by spatial location and high amounts were detected after leaving, compared to before entering the city which indicates that municipal wastewater is the main source of metal pollution. However, all water tests met the WHO's authorized limits. The average detected concentrations of copper, iron, manganese, and lead ranges from 0.003 to 0.025 mg/L, 0.000 to 0.054 mg/L, and 0.057 to 0.112 mg/L, and 0.014 to 0.135 mg/L respectively, while the highest concentrations of copper and iron were recorded significantly in Bedare (0.025 mg/L, 0.054 mg/L) respectively. The highest concentration of Lead (Pb) was detected in Chamtre and Tawke 0.117 mg/L and 0.135 mg/L respectively and this increase may be due to the presence of oil in the discharged industrial wastewater, in this village. Regarding season’s effects, higher mean concentrations for Mn 0.13423 mg/L, Fe, and 0.04208 mg/L were recorded in the autumn season. However, copper and lead had higher mean concertation 0.02389 mg/L, and 0.097 mg/L respectively, during the winter season, while the lowest mean concentration of copper was recorded in autumn, and lead in the summer season had a minimum concentration. There was a significant difference (P <0.01) in the seasonal variation of Cu, Fe, Mn, and Pb (P=0.001).