Cheng et al. (2026) Hydrologically driven coordination of transboundary floods

Identification

• Journal: Journal of Hydrology
• Year: 2026
• Date: 2026-02-20
• Authors: Changgao Cheng, Qinghua Pang, Qin Zhou, Zhou Fang, Shi Xue, Shuang Zhao, Yuan Zhuang, Zhongde Huang, Yan Tang, Mingjiang Deng
• DOI: 10.1016/j.jhydrol.2026.135159

Research Groups

• School of Economics and Finance, Hohai University, China
• School of Sociology and Population Studies, Nanjing University of Posts and Telecommunications, China
• Center for Integrative Conservation & Yunnan Key Laboratory for Conservation of Tropical Rainforests and Asian Elephants, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, China
• University of Chinese Academy of Sciences, China
• Department of Natural Resources and Environmental Sciences, The University of Illinois at Urbana-Champaign, USA
• College of Business Administration, Ningbo University of Finance & Economics, China
• Business School, Hohai University, China
• College of Computer and Information, Hohai University, China
• College of Water Conservancy and Hydropower Engineering, Hohai University, China

Short Summary

This study develops a hydrologically driven coordination framework integrating physical flood routing into an open-loop differential game for transboundary flood management in the Yarlung Tsangpo–Brahmaputra River Basin. It demonstrates that cooperative strategies, accounting for hydrologic travel time, significantly reduce downstream flood peaks and suprathreshold flow durations compared to noncooperative approaches.

Objective

• To develop a hydrologically driven coordination framework that integrates physical flood routing into an open-loop differential game to optimize transboundary flood management.
• To derive and compare optimal flood management strategies under full cooperation, noncooperative Nash equilibrium, upstream minimum release, and risk-averse scenarios, quantifying their welfare implications in the Yarlung Tsangpo–Brahmaputra River Basin.

Study Configuration

• Spatial Scale: Yarlung Tsangpo–Brahmaputra River Basin (transboundary river basin).
• Temporal Scale: Flood wave propagation over hours to days; coordination strategies involving a pre-release advance of approximately 13 days and a reduction in suprathreshold flow duration by 18 days.

Methodology and Data

• Models used: Hydrologically driven coordination framework integrating physical flood routing into an open-loop differential game. Semi-analytical solutions derived for optimal strategies under various scenarios.
• Data sources: Not explicitly specified as satellite, observation, or reanalysis. The study focuses on a modeling framework development and application.

Main Results

• Modeling hydrologic travel time fundamentally alters strategic interactions in transboundary flood management.
• Under full cooperation, an upstream pre-release advance of approximately 13 days and staggered peak shaving emerge as optimal strategies.
• This cooperative coordination reduces downstream flood peaks by 19.4 % and shortens suprathreshold flow durations by 18 days relative to the noncooperative baseline.
• Uncoordinated actions lead to timing mismatches that exacerbate flood extremes.
• Total basin welfare is highest under full cooperation, followed by the Nash outcome, risk-averse, and minimum-release strategies.
• Sensitivity analyses highlight the value of harmonizing damage assessment standards and aligning information sharing with physical travel times for robust cooperation.

Contributions

• Development of a novel hydrologically driven coordination framework that integrates physical flood routing into an open-loop differential game for transboundary flood management.
• Derivation of unique optimal trajectories and closed-form expressions for various strategic scenarios, enabling transparent welfare comparison.
• Quantification of the significant benefits of cooperative flood management, demonstrating how accounting for hydrologic travel time fundamentally changes strategic interactions and improves outcomes (e.g., 19.4 % reduction in flood peaks, 18 days reduction in flow duration).
• Provides a quantitative basis for designing robust transboundary cooperation strategies by highlighting the value of harmonizing damage assessment and aligning information sharing with physical travel times.

Funding

• Not specified in the provided text.

Citation

@article{Cheng2026Hydrologically,
  author = {Cheng, Changgao and Pang, Qinghua and Zhou, Qin and Fang, Zhou and Xue, Shi and Zhao, Shuang and Zhuang, Yuan and Huang, Zhongde and Tang, Yan and Deng, Mingjiang},
  title = {Hydrologically driven coordination of transboundary floods},
  journal = {Journal of Hydrology},
  year = {2026},
  doi = {10.1016/j.jhydrol.2026.135159},
  url = {https://doi.org/10.1016/j.jhydrol.2026.135159}
}