Water use and economic growth decoupling in the Yangtze River Basin driven by technological and structural change over two decades

Based on water resource utilization data from 11 provinces and municipalities in the Yangtze River Basin from 2002 to 2022, this study systematically investigates the impacts of technological and structural effects on the decoupling of water resource utilization and economic growth using structural decomposition analysis. Key findings include: (1) The technological effect dominated the decoupling process, contributing 75.69% of the decoupling force on average during 2002–2022. (2) Significant spatial heterogeneity exists: Lower-basin provinces like Shanghai and Jiangsu achieved technology-driven decoupling, while middle- and upper-basin provinces faced structural lock-in challenges. (3) Temporally, technological and structural effects contributed comparably during 2002–2007 at -50.87% and − 31.63% respectively. By 2017–2022, structural effects weakened to -12.05%, while technological effects became the primary driver at -121.59%. These results suggest region-specific water governance strategies: developed lower reaches should address diminishing technological dividends, while middle and upper reaches require structural reforms to break industrial lock-ins. This study provides a scientific foundation for balancing ecological protection and high-quality development in the Yangtze River Basin.