Regional flood estimation for ungauged basins in Sarawak, Malaysia

Abstract

Design flood estimation is an important task that is required in the planning and design of many civil engineering projects. In this study, the flood records of more than 23 gauged river basins in Sarawak, Malaysia, are examined using an index-flood estimation procedure based on L-moments. Two homogeneous regions were identified and the Generalized Extreme Value and the Generalized Logistic distributions are found to describe the distribution of extreme flood events appropriately within the respective regions. A regional growth curve is subsequently developed for each of the regions. These curves can be used for the estimation of design floods in ungauged basins in Sarawak within the limitations identified for the method. The results presented herein are useful for practicing engineers in Sarawak while the general methodology may be used in any other regions, provided flood records are available.

Application of the L-moments approach to the analysis of regional flood frequency in Northern Algeria

“…The IFM is commonly used to develop regional flood frequency models for ungauged or gauged sites where there is insufficient hydrological information to reliably estimate extreme events (Cunane 1987;Watt et al, 1989;Portela and Dias, 2005;Saf, 2009;Nyeko-Ogiramoi et al, 2012;Ellouze and Abida, 2008). Worldwide application of the L-moments method with the IFM in regionalisation studies of maximum flow rates has yielded very satisfactory results (Vogel and Fennessey, 1993;Madsen et al, 1997;Lim and Lye, 2003;Ferro and Porto, 2006;Ellouze and Abida, 2008;Saf, 2009;Mishra et al, 2009;Hussain, 2011). This is called an index-flood approach to regional frequency analysis (Dalrymple, 1960).…”

Frequency Analysis of Annual Maximum Flood for Segamat River

“…The analysis was done using annual maximum rainfall series for several time resolutions obtained from 17 recording rain gauges that are located all over the peninsular. Meanwhile, GEV and Generalized Logistic distribution are identified as the best fitted distribution for frequency analysis using annual flood data from more than 23 gauged river basin in Sarawak, Malaysia [15]. Fig.…”

TRMM Satellite Algorithm Estimates to Represent the Spatial Distribution of Rainstorms

“…Meanwhile, the lesser rainfall seasons, SouthWest Monsoon (SWM) occurs from May to September and two transition periods occur in April and October. Average rainfall varies between 3000 to 5500 mm annually and temperature fluctuates within the range of 20º C to 36º C [13][14][15]. …”