Driving factors for urban flooding/waterlogging in different zones in Jincheng city

Study of city flooding/waterlogging with different spatial characteristics is key for flood prevention and improved drainage． The main urban area of Jincheng city is studied here. The SWMM-ICM-WCA2D model is improved to simulate drainage and surface inundation states of pipe networks under different rainfall scenarios, to analyze the driving factors of urban flooding/waterlogging for dense pipe network areas and sparse pipe network areas． The waterlogging in dense pipe network areas is found mainly influenced by rainfall intensity, pipe network drainage capacity and topographic features． The design standard of the current pipe network in the main urban area is low, the drainage capacity is saturated under 5-year rainfall condition． The water depth in the inundation area with elevations of < 751 m in the sparse area of the pipe network is larger． The water depth in the rest of the area with higher elevations is smaller but the flow rate is larger． The correlation between pipe network indicators and inundation elements is strong under different rainfall scenarios, especially at greater water depths of > 1 m．