Performance assessment of the Devegeçidi irrigation scheme based on irrigation performance indicators under climatic variability (2019–2024)

Irrigation unions in Türkiye officially began operating under the legal framework of the Irrigation Unions Law No. 6172, enacted on March 8, 2011. Despite the legal foundation, fluctuations in system performance frequently occur due to climatic conditions, natural disasters, and farmer behavior. For this reason, the present study aims to evaluate the irrigation performance of the Devegeçidi Dam irrigation area for the period 2019–2024. Focusing on the most recent 6-year period enables assessment of the influence of climatic shifts, pandemics, and natural disasters on irrigation performance. In the study, key performance indicators such as Water Supply Ratio (WSR), Irrigation Ratio (IR), Collection Ratio (CR), and Sustainable Irrigation Ratio (SIR) were examined, and annual trends were evaluated. According to the findings, irrigation ratios ranged from 74.17% to 87.87%, water supply ratios from 0.98 to 1.58, collection ratios from 59.06% to 96.03%. The sustainable irrigation ratio remained constant at 64.16% throughout the period. Additionally, annual changes in the crop pattern within the irrigated area were analyzed to determine the relationship between water use and crop preference. The results provide significant insights into both the technical and economic sustainability of the irrigation system. The findings show that irrigation performance in the region is susceptible to disasters, water availability, climatic variability, and economic conditions.