Risk assessment of failure of multicrop irrigation rules in complex irrigation systems under the background of climate change

Amid intensifying global climate change, extreme hydrometeorological events have become increasingly frequent, posing significant challenges to irrigation systems that depend on the coordinated operation of multiple water-source infrastructures, particularly reservoir–pumping station systems. To address the limitation that existing studies primarily focus on single water sources or historical statistical analyses, while lacking quantitative evaluations of synergistic failure risks among multiple water-source projects under future climate scenarios, this study proposes a comprehensive risk assessment framework. Using a typical irrigation district in Jiangsu Province, China, as a case study and daily meteorological data from 1970 to 2017 as the baseline, the proposed framework quantifies the failure probability of existing irrigation rules under future climate scenarios and identifies the corresponding critical failure thresholds. The results indicate that, under the drier IPSL-CM5A-LR climate scenario, the failure probability increases significantly compared with that under the wetter BNU-ESM scenario, with the projected failure occurring 23 years earlier than under the historical baseline conditions. Compared with previous studies on irrigation engineering risk assessment, the proposed framework enables a comprehensive end-to-end evaluation encompassing meteorological drivers, runoff simulation, rule extraction, and failure probability quantification. It therefore provides a transferable decision-support tool for enhancing the climate resilience of agricultural infrastructure in water-receiving regions.