Ren et al. (2025) From seasonal variability to long-term trends: a comprehensive analysis of reservoir-induced flow regime alterations

Identification

• Journal: Journal of Hydrology
• Year: 2025
• Date: 2025-12-25
• Authors: Kang Ren, Shengzhi Huang, Vijay P. Singh, Chongyu Xu, Guoyong Leng, Hongbo Zhang, Qiang Huang
• DOI: 10.1016/j.jhydrol.2025.134863

Research Groups

• College of Hydraulic & Environmental Engineering, China Three Gorges University, Yichang 443002, China
• State Key Laboratory of Eco-Hydraulic in Northwest Arid Region of China, Xi’an University of Technology, Xi’an 710048, China
• School of Water Conservancy, North China University of Water Resources and Electric Power, Zhengzhou 450046, China
• Department of Biological and Agricultural Engineering and Zachry Department of Civil & Environmental Engineering, Texas A&M University, College Station, TX, USA
• Department of Geosciences and Hydrology, University of Oslo, P O Box 1047 Blindern, N-0.16 Oslo, Norway
• Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
• School of Water and Environment, Chang’an University, Xi’an 710054, China

Short Summary

This study comprehensively assesses the seasonal variations and long-term trends (1980-2020) of reservoir-induced flow regime alterations across the Contiguous United States, revealing distinct intra-annual patterns and significant reductions in high flow impacts alongside increases in low flow impacts over recent decades.

Objective

• To comprehensively assess the impact of reservoir operations on natural flow regimes across the Contiguous United States, considering both seasonal variability and long-term trends, to inform sustainable river management for ecosystem conservation.

Study Configuration

• Spatial Scale: Contiguous United States (CONUS)
• Temporal Scale: 1980 to 2020

Methodology and Data

• Models used: Dynamic time warping algorithm (for clustering High and Low Flow Impacts - HFIs and LFIs)
• Data sources: Reservoirs’ inflows

Main Results

• Reservoir operations exhibit notable seasonal variations in their impacts on high and low flows throughout the year.
• Annual mean High Flow Impacts (HFIs) and Low Flow Impacts (LFIs) show positive correlations.
• Three distinct intra-annual patterns were identified for both LFIs and HFIs, with minimal correlation to geographical location or primary reservoir purposes.
• Long-term trends (1980-2020) indicate substantial reductions in HFIs and simultaneous increases in LFIs in numerous reservoirs.
• These trends are not associated with reservoir capacities, discharge levels, or the degree of regulation but are correlated with trends in annual mean flows.

Contributions

• Provides a comprehensive assessment of reservoir-induced flow regime alterations across the Contiguous United States, integrating both seasonal variability and long-term trends.
• Introduces a method to identify admissible flow variation ranges based on reservoir inflows.
• Utilizes the dynamic time warping algorithm for detailed intra-annual analysis of high and low flow impacts.
• Highlights the complex and evolving nature of flow regime alterations, emphasizing the need for adaptive management strategies.
• Offers critical insights for developing sustainable river management practices that balance human water needs with ecosystem conservation requirements.

Funding

• Funding information is not available in the provided paper text.

Citation

@article{Ren2025From,
  author = {Ren, Kang and Huang, Shengzhi and Singh, Vijay P. and Xu, Chongyu and Leng, Guoyong and Zhang, Hongbo and Huang, Qiang},
  title = {From seasonal variability to long-term trends: a comprehensive analysis of reservoir-induced flow regime alterations},
  journal = {Journal of Hydrology},
  year = {2025},
  doi = {10.1016/j.jhydrol.2025.134863},
  url = {https://doi.org/10.1016/j.jhydrol.2025.134863}
}