Evaluation of Hydraulic Structures for Agricultural Discharge Optimization

Abstract

The objective of the research was to evaluate the hydraulic structures on the Al-Gharraf River in southern Iraq and their ability to achieve the required discharge for agricultural areas that depend on them. Al-Gharraf head regulator discharges unstable volumes of water, ranging from 280 m3/s in winter to 100 m3/s in summer. The research aimed to determine whether the operational discharges are achievable for the offtakes branching from the Al-Gharraf River when the river's discharge ranges from 60% to 100% of the operational discharge. The researchers utilized a simulation of the irrigation channel (SIC) model to simulate river flow. The researchers used hydraulic indicators such as Delivery Performance Ratio (DPR), Discharge Deviation (∆Q), and Sensitivity (S) to evaluate the work of the hydraulic structures (regulators), determine the more and less efficient regulators in delivering water to the offtakes, and determine the reasons for inefficiency. Depending on the discharge values for each offtake from simulation results by SIC and calculating the hydraulic indicators, it is observed that some offtakes exceed their operational discharges, such as Al-Zydia and Al-Sabila. Also, some offtakes do not receive their operational discharge (Al-Dawaiya, Shatt Al-Shatra, and Al-Basra) projects, which failed to reach even 10% of their operational discharges. The researchers suggest redesigning some offtakes and ensuring reasonable control of gate openings for other offtakes to make the water distribution proportional. Doi: 10.28991/CEJ-2024-010-05-010 Full Text: PDF