DEVELOPING RAINFALL INTENSITY-DURATION-FREQENCY RELATIONSHIP FOR BASRAH CITY

The rainfall Intensity-Duration-Frequency (IDF) relationship is one of the most commonly used tools in water resources engineering, either for planning, designingand operating of water resource projects, or for various engineering projects against floods. The purpose of this paper is to develop an empirical formula to estimate design rainfall intensity based on intensity–duration–frequency (IDF) curvesfor Basrah City. These curves have been generated from a 31-year recordedrainfall data. The study showedmaximum intensities occur at shout duration large variations with return period, Furthermore ,it also notice ; at long duration there is no much difference in intensities with return period.