Study on the Impact of Sudden Pollution on Water Resources: A Case Study of Nanjing Section of Yangtze River

Sudden water pollution accident is a major threat to water quality of drinking water sources. In this study, the process of pollutant and transport was examined based on two-dimensional hydrodynamic and quality model simulations by taking the Nanjing section of the Yangtze River as an example. Two scenarios (i.e., industrial accident and ship accident) were set up to simulate the transport and diffusion of phenol during the dry season. The results show that in the industrial accident at Machahe, only Longtan water source was affected by 30.5 hours; while in the ship accident at the Yangtze River Third Bridge of Nanjing, all the five water sources were affected. Jiangpu-pukou water source was affected for the shortest time, 18 h and Longtan water source was affected for the longest time, 146 h. Downstream water source was affected for a longer period with the increase in the length of the polluted zone, which was mainly related to the tital action and the ramp terrain in the Nanjing section. The results can provide technical support for regulating water supply during sudden water pollution accidents and can serve as the basis for response to water source emergency.