ARID AND SEMI-ARID REGIONS IDF CURVE GENERATION: CASE STUDY AL QUSIR, EGYPT

Intensity-Duration-Frequency curve is a graphical representation of the likelihood of a specific average rainfall intensity occurring. It is calculated using a mathematical function that links rainfall intensity to duration and frequency. These curves are extensively used in hydrology and civil engineering for flood forecasts and urban drainage design. In water resources projects and hydrological assessments, intensityduration-frequency (IDF) curves are often utilized. The actual distribution of rainfall intensity over the period of rainfall is one of the most critical prerequisites for producing IDF curves, yet short-duration rainfall records are rare in arid places where daily rainfall data is available. Hydrologists can use the Natural Resources Conservation Service's (NRCS) standard synthetic rainfall distributions to generate short-duration rainfall data from daily rainfall data. The main purpose of this research is to demonstrate the technique for creating the IDF curve using daily rainfall data collected from the Al Qusir weather station. Where 36 years were used in this study in 1934 and from 1985 to 2020, where the highest value was recorded at 34 mm and was in 1934 The HyfranPlus program was used to perform frequency analysis on the observed rainfall records. The results of the comparison indicate that the Gamma distribution (maximum likelihood) is best suited to represent the rainfall data for the Al Qusir weather station in this. The results of the corresponding rainfall data for 2, 5, 10, 25, 50 and 100 years were used and the corresponding rain intensity was inferred for every 6 minutes over a 24 hour period. for each of the previous years