Water pollution incidents and their influencing factors in China during the past 20 years

There is an urgent need to explore the current situation of China's water pollution incidents for policymaking, accident prevention, and risk mitigation. This study analyzed 1528 water pollution incidents in China from 2001 to 2020 and explored the spatiotemporal characteristics and causes of incidents and consequent damage. The frequency of water pollution accidents increased in 2004, peaked in 2006, and decreased thereafter with a significant decline in 2016. Due to the developed river networks, high population densities, and increasing environmental awareness, pollution incidents were mostly concentrated in China's relatively industrially developed eastern coastal regions. Illegal emission is the major cause, accounting for 51% of all incidents, but with pipeline construction gradually approaching a peak, pipeline leakage poses a noteworthy risk in the future. Although the severity of accidents has reduced recently, it is still necessary to strengthen the risk prevention strategies for general and major accidents. Furthermore, three key factors, including economic development, regulations and legal system, and public participation in pollution supervision and control, which affect the trends and characteristics of water pollution incidents in China, were discussed. This paper offers valuable insights and suggestions that may have useful implications for policymaking and the prevention of water pollution.