Influence of moving rainstorms on watershed responses

Since rainfall activates watershed responses in hydrologic systems, it is critical information for predicting flow and pollutant transportation, and then impacting watershed management strategies. Therefore, it is important to understand clearly rainfall characteristics in the application of hydrologic and water quality models. The objective of this study was to discuss the influence of storm movement on runoff predictions and pollutant exports in a conceptual catchment. The Virginia stormwater for windows (WinVAST) model was applied to predict watershed responses in this work. The result shows that the storm direction has stronger influence on hydrograph shapes than spatial rainfall excess intensity patterns. However, pollutant exports are significantly influenced by both the direction of storm movement and rainfall patterns. The peak of pollutant concentration could be seriously high, due to the delayed discharge in downstream-moving storms.