Historical Trends and Driving Forces of River Water Quality Improvement in the Megacity Shenzhen, China

The water quality of urban rivers in China has undergone significant improvement since the 13th Five-Year Plan period (2016–2020). Among these, Shenzhen are most representative. Assessing historical trends and analyzing driving forces river is great importance provides valuable insights. This study selects two typical watersheds, Maozhou River Longgang River, to explore how link with control projects from 2003 2020. were evaluated using a recently developed index called WQI-DET, which considers DO, COD, NH3-N, TP, anionic surfactants. Results showed that both seriously polluted before 2010 gradually improved during 12th period. After 2010, rapidly thanks environmental remediation mainstream, especially interception project around 2015. rainwater sewage diversion renovation mainly contributed meeting standards for Class IV bodies reveals semi-quantitative between comprehensive pollution engineering measures. It helpful review useful reference other cities.