The observations of flash flood events in the Yangtze River Delta region

We have selected and observed 7 representative watersheds in the Yangtze River Delta region. The discharge stations in the outlets and several rainfall gauges for each basin were set to observe streamflow and rainfall, respectively. The total rainfall for each basin is estimated via the Thiessen polygon method. Overall, a total of 172 flash flood events during the rainy season, caused by extreme rainstorms, in these 7 headwater basins is observed.