Abstract: Taking the Jielin River in Jieshou City, Fuyang area as an example, this paper uses chemical oxygen demand (COD) and ammonia nitrogen as indicators, and divides the study area into industrial area, residential area and urban village according to the sewage water quality and pollutant concentration. A single rainfall event with a rainfall intensity greater than 1 is studied, the maximum value method is used to generalize the overflow in the area as a continuous and constant pollution source, the quality-based interception ratios are designed, and the MIKE11 hydrodynamic water quality model is established. From the two aspects of reducing pollutants in the river and increasing the dynamic water environmental capacity, the interception effects of quality-based interception and traditional interception are compared. The results show that when the traditional interception ratios are used, $ \rho_{COD} $ and $ \rho(NH_{3}-N) $ at the river chief system section of Jielin River are reduced by 28% and 25%, respectively; when the quality-based interception ratios are used, $ \rho_{COD} $ and $ \rho(NH_{3}-N) $ decrease by 39% and 32%, respectively. In terms of the dynamic water environmental capacity of COD and ammonia nitrogen, the quality-based interception increases by 30% and 16%, respectively, compared with the traditional interception. It can be concluded that the effect of the quality-based interception on river water quality improvement is better than that of the traditional interception. The study can provide reference for the selection of the interception ratio of confluent drainage system in old urban areas.
Keywords: MIKE11 model; quality-based interception; water environmental capacity; interception ratio
合肥工业大学学报自科版