Long-term evolution of urban water services in Shaanxi Province, China (2000–2023): A coupling coordination analysis perspective

Study region Shaanxi Province, China. Study focus Urban water service is essential for sustaining resilient cities. In this study, to explore its evolution in response to rapid socioeconomic development under natural water resources constraints from 2000 to 2023, a composite system (NSUW) consisting of natural water resource endowment (N), socio-economy (S), urban water supply (U), and wastewater collection and treatment (W) subsystems was constructed. The coupling coordination degree model, K -means clustering, and obstacle degree model were applied to assess the NSUW system’s development level and obstacle factors. New hydrological insights for the region The NSUW system maintained a high coupling degree of approximately 0.90 after 2006 and the development degree rose from 0.18 to 0.34, while its coupling coordination degree increased from 0.37 to 0.53, evolving from mild dissonance to coordination. The coupling coordination evolution of ten prefecture-level cities exhibited three patterns including “Economy-led”, “Resource-constrained”, and “Resource-conservation”. The obstacle degrees of S and W subsystems decreased while those of N and U subsystems increased. As for the key obstacles, water scarcity was identified as a prominent constraint in Xi’an, whereas the U or W subsystem was found to be the restrictive factor for remaining cities. These findings improve understandings of how urban water services evolved under different combinations of water resources availability and socioeconomic development in arid and semi-arid regions.