Research of risk assessment system on water function areas

Abstract

Accidents that lead to water pollution are frequent and have seriously affected the aqueous environments of water function areas in recent years. Risk assessments of water function areas at the appropriate scale could provide a useful tool for addressing such accidents. Serious damage is caused to water function areas by water pollution accidents, and an accurate early warning management system for such accidents in water function areas has not been developed. Thus, this study proposes a new method of conducting risk assessments for water pollution accidents in water function areas based on an index system of environmental risk to resolve these problems. Using the analytical hierarchy process and expert scoring, a quantitative index system was constructed using a one-dimensional steady mixed decay model and GIS spatial analysis tools. The method was applied to the water function area of the mainstream in the Taizi River Basin. The results of the risk map show that risk increases along with the direction of flow affected by the upstream industrial point sources. Risk regionalization was performed for water pollution accidents in the water function area of the Taizi River Basin, and five high-risk regions and three moderate-risk regions and three low-risk regions were identified. The results objectively reveal the spatial distribution of the risk of water pollution accidents in the water function area of the Taizi River Basin.