Spatial-temporal variation of permanganate index under accident conditions during different water periods in Zigui drinking water source area, Three Gorges reservoir area, China

With the rapid development of the economy, the risk of pollution accidents occurring in urban drinking water source areas has increased, which has brought important impacts on people’s living and social economy. From the emergency treatment of accidents such as chemical spills and explosions from all over the world. Some treatments have limited effectiveness due to lack of understanding for pollution scope and its development trend, leading to pollutant diffusion and more serious impacts. Therefore, it is meaningful to carry out researches on selecting a suitable model to simulate the time variations and spatial distributions of pollutant concentrations in different water periods under accident conditions. This study chose a method that can simulate the temporal and spatial variations of pollutant concentrations under accidents conditions in the drinking water source area. And parameter calibration and model validation were carried out. The method was applied to the Zigui drinking water source area. It is located in the Fenghuangshan area of Zigui County, Yichang City and it supplies water to Zigui County and has a water supply population of 40,000. In this paper, the permanganate index was selected as the characteristic index, The change of the permanganate index over time in the water intake of the drinking water source area, the change of the maximum permanganate index of the drinking water source area over time, and the temporal and spatial variation of the permanganate index of the whole drinking water source area were analyzed, and the change of permanganate index in different water periods of the drinking water source area were compared. Under the assumption of accident conditions, the permanganate index of the drinking water source area intake of drinking water reached the standard after 1.93 h of dry period, reached the standard after 1.74 h of falling period, reached the standard after 1.73 h of flood period and reached the standard after 1.72 h of impounding period. The permanganate index of the whole drinking water source area reached the standard after 4.39 h of dry period, 3.98 h of falling period, 2.48 h of flood period, and 2.47 h of impounding period. This new model can predict the spatial-temporal variation of pollutants and it can provide a reference and a tool for relevant researchers and managers to provide technical support for water resource management.