The current study was conducted on the southern part of Gharaf River in order to define the physical-chemical properties and the impact of the Tigris River’s floodplain water on its ecological characteristics during 2019. Four sites were selected along the southern part of the river. The findings showed a strong connection between the temperature of air and water at all sites. A value ranging from 4.85 - 84.65 NTU was reported for turbidity. The water was found to be oligohaline, low alkaline, and well ventilated due to high dissolved oxygen concentrations. Gharaf River is considered to be of questionable clean water, according to the results of BOD5. The total alkalinity values were recorded to be in the range of 92-292.8 mg /L, which are higher than the acceptable limits of 20-200 mg /L CaCO3 for the Iraqi and international water standards. It was also found that Gharaf River water was very hard, but still within the allowable natural water limits (200 mg /L Ca and 150 mg /L Mg). Concentrations of sulphate ranged 50-200 mg / L, while levels of bicarbonate ranged 140-230 mg /L. On the other hand, ranges of 3354-855 mg / L and 3-85 mg / L, respectively, were recorded for TDS and TSS. In addition, nitrates values were found to be in the range of 0.04-5.14 mg / L, being below the permissible limits for Iraqi water (15 mg / L). Other values observed for phosphates were 0.004-0.085 mg / L. Overall, the results demonstrated different effects on the properties of Gharaf River water during and after the floodplain period.
