A simplified BLP-based approach for IBWT operation lacking regulating reservoir: optimization and structural analysis

ABSTRACT To resolve inter-basin water transfer (IBWT) scheduling challenges without regulating reservoirs, this study proposes a simplified bi-level programming (SBLP) framework. This framework introduces a terminal equilibrium reservoir (TER) and integrates water transfer with local supply scheduling lines, converts the original bi-level model into a single-level optimization. This framework incorporates essential spillage reduction and end-period water level iteration modules, establishing a many-objective optimization framework solved via NSGA-III. The results applied to an IBWT project in Shanxi, China show that SBLP's dual capability to reduce dimensionality while enhancing transfer-demand alignment; the valve chamber flow threshold has a significant impact on scheduling flexibility, increasing TER's admission flow threshold can strengthen the operational synergy; time-dependent mode exhibit marginal superiority over time-averaged mode under identical algorithmic conditions; optimized scheduling substantially improves TER utilization, with most pareto solutions dominating the original design across objectives except operational costs, persistent challenges remain in discovering boundary solutions; compared to computationally expensive nested BLP frameworks, SBLP is more efficient and provides more balanced solution set; SBLP's active adjustment mechanism also prevents the over-extraction common in aggregated–decomposed frameworks. This study's methodology holds potential for future IBWT operation research.