Deriving Rainfall Intensity-Duration-Frequency Relationships fo Kerbala
MUTHANNA JOURNAL OF ENGINEERING AND TECHNOLOGY (MJET)
Dr. Ayad Kadhum Hussein
University of Kufa/College of Engineering/Structural and Water Resources Engineering
E-mail addresses: Dr.ayad.alkafajy@Gmail.com
Intensity-Duration-Frequency (IDF) relationship of rainfall amount is one of the most
commonly used tools in water resources engineering for planning designing, and operation of
water resources projects. The objective of this research is therefore, to develop operational
IDF relationships for the provinceof Kerbala based on historical data. The IDF curves have
been developed considering application to Kerbala area and presented in the form of general
mathematical equation, curves relating Intensity–Duration-Frequency of rainfall. The IDF
curves are plotted for 2, 5, 10, 25, 50 and 100-year return periods in Kerbala. The values of
the constants α, γ and exponents β, τ in the IDF function are calculated from the observed
precipitation data by using different methods.Using themethods ofgoodness of fit has been
reached in Kerbala that the Log Pearson type III is the best method of other methods.
Keywords:plotting position,rainfall frequency analysis.