Abstract

Enhancing water use efficiency hinges on improving water consumption and the performance of irrigation systems. Nevertheless, challenges such as limited access to historical and current data, difficulty in securing continuous data, conflicts, the inability to cover vast areas, and high costs impede the monitoring and assessment of irrigation performance. This study aims to evaluate the water consumption patterns and irrigation performance indicators using open-access datasets. The study demonstrated the actual evapotranspiration and irrigation performance indicators, including water productivity, equity, adequacy, relative water deficit, and beneficial fraction. QGIS and ArcGIS were used to conduct spatiotemporal analysis on the locations of irrigated fields (lower, middle, and upper) across the Koga irrigation scheme. The WaPOR datasets on water, climate, and land, with a spatial resolution of 30 m and real-time temporal resolution, were used for the analysis of the irrigation scheme. The findings indicated that in the 2018 irrigation season, the minimum values for actual evapotranspiration, transpiration, biomass, and yield were 439 mm, 326 mm, 5.9 t ha^-1, and 2.8 t ha^-1, respectively. The estimated delivery performance indicators were categorized as poor for adequacy and relative water deficit, fair for equity, and acceptable for beneficial fraction. These outcomes provide insights into the features of irrigators and the overall trends in irrigation systems. The spatial and temporal analysis of delivery performance indicators highlighted that agronomic practices, management, and operations are the factors contributing to water scarcity in the irrigation scheme. In conclusion, our findings highlight that open-source data offers valuable insights for evaluating and overseeing water consumption and the performance of irrigation schemes in data-scarce regions.