Monte Carlo simulation of flood frequency curves from rainfall : the way ahead

This paper summarises the results of a 3-year research project by the CRC for Catchment Hydrology (CRCCH) on the joint probability approach (Monte Carlo simulation technique) to design flood estimation and the subsequent research activities to further the CRCCH method towards industrial applications. It identifies significant shortcomings in the current design event approach to rainfall-based design flood estimation, and argues that substantial improvements in the accuracy and reliability offlood estimates can be obtained from a more rigorous treatment of probability aspects in the generation of design floods. Applications of the proposed Monte Carlo simulation approach to test catchments in Victoria and Queensland have produced promising results, and demonstrated the feasibility and in-principle advantages of the approach. More recently, the Monte Carlo simulation approach has been integrated with the industry-based flood estimation model URBS thus significantly broadening its range of application. The paper disusses how far the recent research on the joint probability approach has advanced towards resolving the main research issues, and outlines desirable future development work to allow the new method to be routinely applied as a design tool.