Water resources evaluation and driving factor analysis in nine provinces of Western China based on water footprint theory

• Water footprint fluctuated, with virtual water footprint as the main contributor (67.01%–86.60%). • Study area has weak sustainable water resource utilization. • Economic development and technology are key positive and negative drivers of water footprint. The Western China is characterized by scarce rainfall and fragile ecological environments. The quantity and utilization of water resources determine the region’s development prospects. Previous studies have assessed water resource changes in this region using the water footprint concept but struggled to quantify actual water consumption, resulting in double counting of blue water and gray water. This study applies the virtual water footprint theory to integrate water footprint and water stress indicators from 2015 to 2023. It establishes a multi-dimensional water resource evaluation system, and uses the LMDI method to identify driving factors. Results show an uneven spatial distribution of per capita water footprint, with virtual water footprint accounting for 67.01% to 86.60% of total water resource consumption. And the results of this method are overall 30% to 40% smaller. Overall water stress is manageable, but water supply–demand conflicts are significant in Ningxia. Economic and technological effects are the main positive and negative driving factors of the study area’s water footprint, respectively. Thus, industrial upgrading and technological innovation could alleviate these regions’ water resource constraints in multiple ways. Our findings indicate weak sustainable water use capacity in the nine western provinces (regions), providing a scientific basis for optimizing western China’s water resource allocation and devising differentiated water-saving policies.