Abstract:
Estimation of rainfall Intensity-Duration-Frequency (IDF) is commonly required for the design of hydraulic control structures and for water resources engineering planning and development. The use of IDF curves become more cumbersome and hence a generalized empirical relationship was also developed for the study area. The relationship between rainfall intensity, duration and the return period of a certain rainfall amount was determined through statistical analysis of rainfall data. Daily rainfall data for the year 1977 to 2007 were collected from Indian Meteorological Department (IMD) and the IMD empirical reduction formula was used to estimate the short duration rainfall using Gumbel's probability distribution method. Rainfall data collected from the Jammu, Batote and Bhaderwah stations were used to develop the rainfall intensity duration frequency curves with return periods of 2, 5, 25, 50, 100, 200, 500 and 1000 years and using durations of 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 60, 80, 100, 120 and 180 minutes. This study is an attempt to develop IDF curves, which are used in hydraulic design to size culverts and pipes. Keywords: Intensity-Duration-Frequency (IDF) curve, Rainfall intensity, return period, IDF empirical reduction formula.