Abstract: Water use performance and wastewater decontamination performance improvement is an effective way to alleviate water shortage. Industrial production system in China can be divided into production water use sub-system and wastewater decontamination sub-system. By considering the linkages between the two sub-systems and the disposability of pollutants in different sub-systems, a new two-stage network DEA model is proposed to evaluate the performance of china's industrial water use systems. The proposed model is applied to evaluate the performance of 30 regional industrial water use systems of China. The application results show that the overall efficiency of regional water use systems is relatively low in China and the inefficiency is largely driven by wastewater decontamination performance. There exist significant regional disparities in water use efficiencies of regions and areas. In particular, evident relationships between water use efficiency and water resource endowment, and a region may achieve a high efficiency score with relatively lower resource endowment, and vice versa. The proposed model can simultaneously evaluate the efficiencies of the whole industrial water use system and its two sub-systems, and it can identify the key factors that affect the performance of industrial water use systems. The proposed model can also be applied to evaluate regional energy efficiencies. All these show the great practical value of the proposed model.

Key words: data envelopment analysis, industrial water use systems, two-stage model, disposability of pollutants