Abstract:To scientifically evaluate the effectiveness of waterlogging control in plain water network areas, taking Dianshanhu Town in Kunshan City as a study area, the MIKE FLOOD model, which integrates a one-dimensional river network, a two-dimensional terrain, and a one-dimensional drainage network, was used to simulate urban flooding in the plain water network area. The model was calibrated and validated using observed rainfall data, allowing for accurate simulations of maximum inundation depths in current situation and after treatment under four different rainfall return periods: 2-year, 5-year, 10-year, and 20-year events. The simulated results indicate that the inundation area changes significantly under the 20-year return period, while it shows no substantial variation under the other three return periods. For urban waterlogging control under smaller rainfall return periods, priority should be given to upgrading drainage networks, while for intense short-duration storms, the construction of sponge city facilities should take precedence. To address urban flood risks caused by various return periods and short-duration rainfall, a combination of drainage system upgrades and sponge city facilities is recommended.