Flood level characteristics of Puyang River were explored under combined conditions of various flood frequencies in Puyang River and different flood discharge rates for Gaohu flood detention basin based on a 2D hydrodynamic model of Puyang River.The results show that when Puyang River suffers from once flooding in ten years,in twenty years and fifty years the mean flood level at a typical observation point of the east and west branch rivers is reduced by 0.62 m,0.70 m and 0.59 m,respectively.This suggests t...