Can China’s water tax reform promote green water resource efficiency? ——an empirical study based on 280 prefecture-level and above cities

Assessing the impact of water resources tax reform on green water resource efficiency provides useful guidance for building a water-saving society and promoting green development. Based on the panel data of prefecture-level and above cities in China from 2006 to 2020, this paper constructs a super-efficient SBM-DEA model to measure and assess the green water resources efficiency of 280 cities, and empirically tests the impact of water resource tax on green water resources efficiency by using a multi-period double-difference method. The results show that China’s green water resource efficiency at the city level as a whole shows a decreasing and then increasing trend, and at the same time, the pilot of water resource tax can significantly promote the improvement of green water resource efficiency through mechanisms such as optimizing water use structure and reinvesting in water-saving taxation. Based on this, the State Council of China should issue relevant implementing regulations and specific implementation rules for the premise of unification, the State Council of China on the improvement of the basic matters of water resource tax to set a reasonable range or interval, and the local government in the scope of the limitations of the scope of the implementation of the pilot program in accordance with the characteristics of the local conditions, so as to achieve the further promotion of water resource tax system reform. At the same time, China should expand the scope of the pilot program in due course on the basis of this foundation, so as to give full play to the policy effect of water resource tax and continuously improve the efficiency of green water resources.