Abstract
![CDATA[Estimation of large to rare floods is important in the planning and design of large hydraulic structures and many other important water resources management tasks. This is regarded as a difficult challenge due to limited availability of observed flood data in this range of flood magnitudes. Methods used to estimate large to rare floods involve significant extrapolation beyond the available flood data, either using a rainfall-runoff model or empirical methods. This paper presents a simple Large Flood Regionalisation Model (LFRM) which is relatively easy to apply in practice as it is based on a small number of easily obtainable predictor variables. The LFRM assumes that the maximum observed flood data over a large number of sites in a region can be pooled together by accounting for the at-site variations in the mean and coefficient of variation (CV) of annual flood maxima. The LFRM in this paper builds on previous research work by combining it with a spatial dependence model that accounts for the reduction in net information available for regional analysis (i.e. the number of independent sites Ne). The main interest of the LFRM is its application to ungauged catchments, which has been achieved in this study by developing prediction equations using Bayesian Generalised Least Squares regression with the region-of-influence approach to estimate the mean and CV of the annual maximum flood series as a function of catchment characteristics. The LFRM is developed and tested in this paper using data from 626 catchments across the Australians continent. An independent test has shown that the new LFRM can provide quite reliable design flood estimates for the large to rare flood range when compared to a world model and other established methods.]]
Original language | English |
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Title of host publication | 2012 Hydrology and Water Resources Symposium : 19-22 November 2012, Dockside, Cockle Bay, Sydney, NSW Australia |
Publisher | Engineers Australia |
Pages | 969-976 |
Number of pages | 8 |
ISBN (Print) | 9781922107626 |
Publication status | Published - 2012 |
Event | Hydrology and Water Resources Symposium - Duration: 19 Nov 2012 → … |
Conference
Conference | Hydrology and Water Resources Symposium |
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Period | 19/11/12 → … |
Keywords
- Australia
- flood forecasting
- rain and rainfall