Abstract
Surface water quality in China has improved substantially over the past decade but has plateaued recently under current levels of industrial activity and nutrient (N, P, and chemical oxygen demand) discharge standards. This stagnation signals the need to identify previously underestimated drivers and actionable thresholds for achieving Sustainable Development Goal (SDG) 6.3 (clean water and sanitation). A high-resolution national water quality dataset was analyzed in this study using the random forest method, partial dependence analysis, and a modified coupling coordination degree model. Results revealed that groundwater extraction and petroleum pollution now surpass conventional nutrients in water-scarce regions and industrial clusters. The three dominant factors are per capita water resources, petroleum discharge, and groundwater usage, with thresholds for good water quality at 985 m3 per person per year, 108 tons per year, and 25.5 × 108 m3 per year, respectively; falling below these thresholds reduces water quality by 5–10%. The COVID-19 pandemic period highlighted reduction of petroleum pollutants as a key factor associated with water quality recovery. Based on these findings, a spatially differentiated management paradigm was proposed that prioritizes groundwater restoration in arid northern China, stringent petroleum control in coastal industrial clusters, and integrated water–agriculture measures in northeastern farmlands. This threshold-based, mechanism-explicit framework offers a pathway toward realizing SDGs in China, and provides a transferable methodology for other countries addressing the water–development–pollution nexus.
Subjects
- Climate sciences
- Environmental sciences
- Environmental social sciences
- Hydrology
- Water resources
Acknowledgements
This work was financially supported by the National Key Research and Development Program of China (2022YFC3204000) and the National Natural Science Foundation of China, China (42407513). We thank James Buxton MSc for editing the English text of a draft of this manuscript.
Author information
Authors and Affiliations
Corresponding authors
Ethics declarations
Competing interests
The authors declare no competing interests.
Additional information
Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Supplementary information
Supplementary information (download PDF )
Rights and permissions
Open Access This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, which permits any non-commercial use, sharing, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if you modified the licensed material. You do not have permission under this licence to share adapted material derived from this article or parts of it. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by-nc-nd/4.0/.
Reprints and permissions
About this article
Cite this article
Luo, M., Niu, Y., Wang, L. et al. Beyond nutrients: groundwater extraction and petroleum discharge as dominant drivers of water quality in China.
npj Clean Water (2026). https://doi.org/10.1038/s41545-026-00615-1
Received:
Accepted:
Published:
DOI: https://doi.org/10.1038/s41545-026-00615-1
Source: Resources - nature.com
