Simulating rainfall runoff and assessing low impact development (LID) facilities in sponge airport.

Abstract

The appearance of extreme weather causes frequent airport flooding, which has a serious impact on the normal operation of an airport. In this study, three simulation scenarios are set in order to study the effect of low impact development (LID) facilities (green roof and vegetative swale) on the water depth of overflow junctions and total inflow to the study area outlet in an airport at different rainfall return periods (2 a, 5 a, 20 a and 50 a). Vegetative swale has better reduction effect on water depth of overflow junctions than has green roof. The reduction rate of vegetative swale is about 25-52% at different rainfall return periods, but the effect of green roof is not obvious. For the double peak rainstorm, the reduction effect on the water depth of overflow junctions after setting vegetative swale for the first rain peak is better than that for the second rain peak. Under the condition of 2 a, 5 a, and 20 a, the total inflow reduction rates of study area outlet after applied green roof and vegetative swale are 16.85%, 20% and 22.17% respectively, and the effect is poor (only 2.26%) at low-frequency return period (50 a). This study can provide theoretical guidance for the design of LID facilities of a sponge airport.