GENERATION OF IDF CURVES IN ARID AND SEMI-ARID AREAS: CASE STUDY HURGHADA, EGYPT

Intensity-Duration-Frequency (IDF) curves are commonly used in water resources projects and hydrological analyses. One of the most important requirements for creating IDF curves is the actual distribution of rainfall intensity during the period of rainfall, but usually short-duration rainfall records are rare in arid regions while daily rainfall data are available. Hydrologists can generate short-duration rainfall data from daily rainfall data through using the Natural Resources Conservation Service (NRCS) standard synthetic rainfall distributions. The main purpose of this paper is to show the procedure to be followed in developing the IDF curves using the daily rainfall data recorded at the Hurghada weather station. Frequency analysis of the observed rainfall records was performed using HyfranPlus software. The gamma distribution is the most widely accepted probability distribution in this research.