Risk Assessment of Sudden Water Pollution Accidents Based on the One-Dimensional Hydrodynamic Model for Weihe River Basin, China

Abstract

The frequent water pollution incidents can lead to deterioration of water environment and increase risk of endangering people's health. According to the characteristics of sudden water pollution accidents, a one-dimensional river-water pollution model was established in this study using hydrodynamic method. Then, taking the Weihe river basin as an example, the longest distance, size of longitudinal dissociation, and the risk range of contaminants were estimated via the model. Moreover, the changes of contaminant concentration risk in the different flow were assessed by the emergency measures of water diversion, which could achieve the purpose of improving water quality in a short time, and greatly reduce the risk of water pollution accidents. The results showed that, in the flow of 30m3.s-1 and 60m3.s-1 the maximum contaminant distance moved forward 34% and 49% than natural condition. Meanwhile, the maximum concentration was decreased by 30 to 40% and the total length section was approximately reduced by 25 to 45%. These validations have showed the method is an ideal tool for making pollution accident emergency treatment. However, the parameters of the model should be adjusted for different watersheds. This study can provide the basis for the water pollution risk decision management.