Abstract: In view of the previous design of the drainage system in the flight area of China′ s airports, the rainstorm recurrence period selected was too small, resulting in insufficient water delivery capacity of the drainage facilities under heavy rainstorms. According to the Specifications for Aerodrome Drainage Design, the storm water management model (SWMM) simulation software is used to simulate and analyze the rainfall and runoff in the flight area of Wenzhou Longwan International Airport, and to discuss the demand law for the spatial parameters of drainage facilities when the rainstorm recurrence period is large. The analysis results show that in the reconstruction and expansion of the airport, the rainstorm recurrence period of P = 5 a should be selected, and the spatial parameter requirements of the specification should be met; for the utilization of existing facilities, the recurrence period of the peak year should be selected for check as much as possible. And measures such as increasing the width of the existing pipe trenches and increasing the parallel diversion can be used to improve the drainage effect, thereby laying a foundation for increasing the rainstorm recurrence period of the drainage facilities. The research results can provide a reference for the comprehensive improvement of the drainage system function of the airport flight area.

Key words: airport flight area, drainage facilities, rainstorm recurrence period, facilities reconstruction and expansion