Efficiency evaluation for regional industrial water use and wastewater treatment systems in China: A dynamic interactive network slacks-based measure model

Abstract

This paper develops a dynamic interactive network slacks-based measure (SBM) model to assess the performance of regional industrial water systems (IWSs) in China. Such a system can be separated into a water use subsystem (WUS) and a wastewater treatment subsystem (WTS). Within this, wastewater and recycled water are interactive intermediate variables, and the capacity of facilities for treatment of wastewater (CTW) can be considered as a carry-over variable, reflecting dynamic components. Based on the proposed approach, we specify an evaluation technique for the subsystem, period, and subsystem period efficiencies. We apply the proposed approach to analyze the efficiencies of 30 regional IWSs in China during 2008–2014, and the results show the carry-over CTW has notable impacts on the overall efficiency of the IWS, especially on WTS efficiency. Only four regions are deemed overall efficient, namely, Beijing, Tianjin, Fujian, and Hainan. The inefficiency of the whole system arises from weaknesses in both the WUS and the WTS. It was found that the eastern area has the highest mean overall efficiency and mean subsystem efficiencies among the three major geographical areas of China.