ABSTRACT

Understanding the driving forces of urban flood variations is important for better formulating future management strategies. This study explores the changes in urban drainage indicators (i.e., catchment area, imperviousness, pipe length and capacity) in historical urbanization and their impacts on urban flood from multiple spatio-temporal scales. By employing a GIS-based processing module, a SWMM-based flood modelling and a statistical analysis, we identify the indicators with significant changes and explore the causal relationships between the indicators and flood volumes in a case study in Northern China. Results showed a clear distinction in drainage indicators at different spatial scales. Flood volume is more sensitive to urban development and drainage performance in urban center. Our regression models explained over 85% of the historical flood variations for all spatial scales at the 90% confidence level. The study contributes to a better discussion of urban flood vs. urbanization patterns and drainage characteristics.