INTENSITY - DURATION-FREQUENCY RELATIONSHIP IN AN ARID AND A SEMI-ARID CASE STUDY WADI EL DOM-EL AIN EL SOKHNA, EGYPT

Intensity–duration–frequency (IDF). They are curves describing the relationship between the intensity of precipitation, duration of precipitation. Ordinarily, intensityduration-frequency (IDF) curves are widely used in hydrology and water resource systems to predict floods and their paths and to design protection structures and rain drainage networks. The intensity, duration, and frequency (IDF) curves are obtained by frequency analysis of rainfall intensity measurements available at meteorological stations. The Natural Resources Conservation Service (NRCS) method is can use for calculating direct runoff volume for a given rainfall event. Consequently, the main objective of this research is to illustrate the steps of the derivation of the IDF curve using rainfall measurements obtained from the meteorological Suez stations. The most popular and widely used distribution of probability functions methods has also been applied to determine the maximum precipitation depth in this study for varied return periods of 2, 5, 10, 25, 50, and 100 years using HyfranPlus. Accordingly, was demonstrated that the findings obtained using the Weibull approach were better than other distributions, the corresponding rain intensity was extracted for every 6 minutes over a 24-hour period for each of the previous years.