Wu et al. (2026) Hierarchical multi-objective management of cascade reservoirs: coordinating long-term strategy and daily operation under hydrological variability

Identification

• Journal: Journal of Hydrology
• Year: 2026
• Date: 2026-08-07
• Authors: Haotian Wu, Zhaoyang Zhu, Zhaocai Wang, Jiachen Kong, Qikai Liu, Zhenlai Tan, Chenye Liu, Tianyu Ren
• DOI: 10.1016/j.jhydrol.2026.136180

Research Groups

College of Information, Shanghai Ocean University (China) Department of Civil and Environmental Engineering, University of California, Davis (USA) College of Hydraulic Science and Engineering, Yangzhou University (China)

Short Summary

This study proposes a Multi-scale Socio-Economic-Environmental Reservoir Management framework to address the scale dilemma in large-scale cascade reservoir operation. The framework restores long-neglected ecological functions while enhancing economic benefits.

Objective

• Investigate the effectiveness of a hierarchical multi-objective management approach for coordinating long-term strategy and daily operation under hydrological variability in cascade reservoirs.

Study Configuration

• Spatial Scale: Cascade reservoir system with three key periods: drawdown period, flood season, and storage period.
• Temporal Scale: 10-day time step (upper-layer model) and daily-scale optimization (lower-layer model).

Methodology and Data

• Models used: Reinforcement learning-enhanced evolutionary algorithm (SPEA2-RLS), RF-AdaBoost-based surrogate model for water temperature predictions.
• Data sources: Hydrological data, ecological-temperature evaluations.

Main Results

• Effective Ecological Hydropeaking Days (EEHD) increased from 0 to 17 in wet years.
• Ecological Flow Deficit (EFD) was substantially reduced by 42.9% in dry years.
• Total Power Generation (TPG) and System Minimum Power Output (SMPO) increased by 4.4% and 14.9%, respectively, while Navigation Interruption Days (NID) were reduced by 30.5% in normal years.

Contributions

This study provides a comprehensive understanding of the dynamic trade-offs among objectives in cascade reservoir operation and reveals the benefits of multi-objective coordination and watershed management.

Funding

• This research was funded by the National Natural Science Foundation of China (Grant No. 52109214).
• The work was also supported by the Shanghai Municipal Science and Technology Commission (Grant No. 20DZ1200300).

Citation

@article{Wu2026Hierarchical,
  author = {Wu, Haotian and Zhu, Zhaoyang and Wang, Zhaocai and Kong, Jiachen and Liu, Qikai and Tan, Zhenlai and Liu, Chenye and Ren, Tianyu},
  title = {Hierarchical multi-objective management of cascade reservoirs: coordinating long-term strategy and daily operation under hydrological variability},
  journal = {Journal of Hydrology},
  year = {2026},
  doi = {10.1016/j.jhydrol.2026.136180},
  url = {https://doi.org/10.1016/j.jhydrol.2026.136180}
}