Impact of temporal rainfall patterns on flash floods in Hue City, Vietnam

Urban flooding is a perennial problem, especially in developing countries with relatively weak infrastructure under ever-increasing stress due to climate change and human activities. We simulate the temporally variable flood-water depth and inundation area under four designed rainfall patterns in the typical tropical rainforest city of Hue, Vietnam. The four rainfall types are R1 (peak at fifth hour), R2 (peak at 20th hour), R3 (peak at first hour), and R4 (peak at 13th hour). Results show that temporal rainfall pattern R4 with peak rainfall in the middle of the total period yielded the maximum water depth of 1.88 m. R3, with peak rainfall in the first hour, yields the shallowest maximum water depth and the largest inundation extent. When the water depth for R3 is 0.1-0.2 m, the inundated area caused by R3 is 3-4 times that of the other three patterns. Analysis of urban flood inundation in Hue provides a management tool to facilitate flood risk management in the context of extreme rainfall.

Automated summary

Urban flooding is a persistent issue, particularly in developing countries with weak infrastructure and increasing stress from climate change and human activities. A study in the tropical rainforest city of Hue, Vietnam, simulated flood-water depth and inundation area under four designed rainfall patterns. The results showed that the timing of peak rainfall in different patterns influenced the water depth and extent of inundation.