FREQUENCY ANALYSIS OF RIVERFLOW IN SABAH AND SARAWAK

Design flood estimation is an important task that is required planning and design of many
civil engineering projects. In this study, the flood records of 37 stations in Sabah and 5
stations in Sarawak are examined using six probability distributions mostly used in Flood
Frequency Analysis which are Weibull Plotting Position, Log-Pearson III, Gumbel Type
I, Log-Normal 2, Log Normal 3 and Pearson Ill. This is a continuation project of
Frequency Analysis in Peninsular Malaysia made by Miss Nabila Abu Bakar, to complete
the study on Frequency Analysis for Malaysia. The primary objective of frequency
analysis is to relate the magnitude of occurrence, flood in this case through the use of
probability distributions. To ease the process, software called DISTRIB which developed by A.P Dr Saied Saiedi (1989) is used to obtain more accurate result. A best fit
distribution with the lowest error is subsequently developed for each station. The results
presented herein are useful for reference for practicing engineers and will be used to
predict high streamflow on any return period