Developing Intensity-Duration-Frequency (IDF) Curves Based on Rainfall Cumulative Distribution Frequency (CDF) for Can Tho City, Vietnam

Information on the relationship between rainfall intensity, duration and accumulation frequency or return period (IDF) is commonly utilized in design management of urban drainage systems. Can Tho City, located Vietnamese Mekong Delta, a city which has recently invested heavily upgrading its stormwater systems hope preventing reoccurring flood events. Yet, much these works were designed based obsolete outdated IDF curves. This paper presents an updated curve for City. For each designated period, cumulative distribution function (CDF) was developed using Pearson III, Log-Pearson Log-Normal functions. In order to choose best CDF empirical formulas used Vietnam Asia (Vietnamese standard 7957:2008, Department Hydrology, Ministry Transportation, Talbot, Kimijima, Bermard) compared. The goodness fit generated by analysis (CDF curve), that predicted assessed efficiency index (EI), root mean squared error (RMSE). built from Vietnam’s TCVN 7957:2008 with new parameters (A = 9594, C 0.5, b 26, n 0.96) showed performance, highest values EI (0.84 ≤EI≤ 0.93) lowest RMSE (2.5 ≤RMSE≤ 3.2), when compared other remnants.