CALCULATION OF DESIGNED FLOOD IN WEAK DATA REGION IN VIET NAM USING WIN-TR55 MODEL

Tóm tắt

Road transportation infrastructure is of great importance in the development of a nation. Viet Nam is facing many challenges in developing road infrastructure due to lack of rainfall and flow data required for calculation of designed flood, especially in mountainous areas. Furthermore, many water drainages have been damaged by heavy rain and severely affected by climate change. In this study, the Win-TR55 based on SCS method is employed for calculating storm runoff volume, discharge and hydrograph to estimate designed flood values for small watersheds. In order to use TR55, parameters for calculating designed flood including rainfall, soil type and land use map are required. This program is widely used in many countries, but has not been applied to the small basins in Viet Nam because of data missing. Tong Soong bridge on the National Highway No.31 crossing Dinh Lap district, Lang Son province, Viet Nam was selected as a case study. The study shows a great potential of the Win-TR55 method to estimate the hydrograph for small and medium watershed in Viet Nam.