JSTE_V3_N1_RP2 N. Vivekanandan Journal on Structural Engineering 2320 - 2343 3 1 7 12 Anderson-Darling, Kolmogorov-Smirnov, Mean Square Error, Probability Weighted Moments, Rainfall Assessment of annual rainfall for a river basin is of utmost importance for planning, design and management of water resources projects. This paper illustrates the use of six parameter estimation methods of Extreme Value Type-1 (EV1) distribution for modelling annual rainfall of Krishna and Godavari river basins. Goodness-of-Fit (GoF) tests such as Anderson-Darling and Kolmogorov-Smirnov are used for checking the adequacy of fitting of EV1 distribution to the recorded rainfall data. A diagnostic test of root mean square error is used for the selection of a suitable method for modelling annual rainfall. Based on GoF and diagnostic test results, probability weighted moments is identified as best suited method for modelling annual rainfall of Krishna and Godavari river basins. March - May 2014 Copyright © 2014 i-manager publications. All rights reserved. i-manager Publications http://www.imanagerpublications.com/Article.aspx?ArticleId=2979