57-Summer Internship Report on Development of IDF Curves Using Daily Rainfall Data For Different Return Periods for Tawi River Basin.

Abstract

Estimation of rainfall Intensity-Duration-Frequency (IDF) is commonly required for the design of hydraulic control structures and for water resources management, planning and development. The use of 1Di:curves become more cumbersome, hence a generalized empirical relationship was also developed for the study area. The relationships between rainfall intensity, duration and the return period of a certain rainfall amount were determined through statistical analysis of rainfall data. Daily rainfall data for the year 1977 to 2007 was collected from IndianMeteorological Department (IMD) for Jammu, Batote and 13hadcrwah stations and the IMD empirical reduction formula was used to estimate the short durationrainfall using Gumbel's probability distribution method. Rainfall data were then used to develop the rainfall intensity duration frequency curves with return periods of 2, 5, 25, 50, 100, 200, 500 and 1000 years for durations of5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 60, 80, 100, 120 and 180 minutes. The results of the study can be used to develop IDF curves which are useful for hydraulic designing of culverts, pipes and small bridges.