To strengthen cooperation among local governmental departments and improve water ecology, China has proposed the river management policy "river chief system + procurator". However, it remains to be verified that intergovernmental cooperative policies contribute to the improvement of China's water ecology. Based on data from 87 national water quality monitoring sites released by the China Environmental Monitoring Station from 2015 to 2022, this paper constructed a multiperiod differences-in-differences model to evaluate the effectiveness of the cooperative governmental policy, the "river chief ...
