Groundwater flow modeling and hydraulic assessment of Al-Ruhbah region, Iraq

Abstract

Al-Ruhbah region is located in the southwest of Najaf Governorate. A numerical model was created to simulate groundwater flow and analyze the water quality of the groundwater, by developing a conceptual model within the groundwater modeling system software. Nineteen wells were used, 15 for pumping and four for observation. A three-dimensional model was built based on the cross-sections indicating the geologic layers of the study area, which were composed of five layers. When a distance of 1,000 m between the wells was adopted, 135 wells can be operated simultaneously. These wells were hypothetically operated at 6, 12, and 18 h intervals, with a discharge of 200, 430, and 650 m3/day, respectively, and the maximum drawdowns of 12.5, 15, and 21 m were achieved. Water was also extracted from five wells in the study area to evaluate the quality of water for irrigation purposes and to characterize the type of water in these wells based on the Food and Agriculture Organization and Iraqi standards. The results of the laboratory tests revealed that the water suffers from different salinity concentrations, so for a large part of the study area, the water is suitable for some plants that can withstand high salt ranges between 3,000 and7,500 μc/cm.