Evolution in flood modelling based on the example of the Eudlo Creek crossing over the Bruce Highway by Anna Kolega and Bill Syme.

Abstract

The evolution of flood modelling to inform design of hydraulic structures and flood risk management has undergone substantial technological advances since the advent of computers. On-going software developments, a shift towards a Monte Carlo approach for design flood estimation, and the opportunities available using Cloud based computing indicate continued advances over the coming years. Of interest is the Bruce Highway crossing of Eudlo Creek, which has been the subject of repeated and wide-ranging flood assessments for over 30 years due to several cross-drainage design investigations and highway upgrades. The latest assessment was the hydraulic analysis for Eudlo Creek as part of the Bruce Highway Interchange Upgrades – Maroochydore Road and Mons Road (BHIUMM) undertaken for WSP and the Department on Transport and Main Roads. This project is identified as a high priority 1 project within the Bruce Highway Action Plan (BHAP). The BHAB was developed in 2012 by the Queensland Government with a view to implementing a generational upgrade in the condition of the Bruce Highway. This project included the development of a new TUFLOW HPC model with a 5m grid resolution, upgraded from an TUFLOW Classic model at a 10m resolution. The model was calibrated to four historic events and simulated for a range of design events using the latest Australian Rainfall and Runoff (ARR) 2019 guidelines, as well as ARR 1987 and Council’s Duration Independent Storm. The previous TUFLOW Classic model was developed in 1999 and validated against a physical model. This paper provides an overview of the evolution of flood modelling over the past 30 years, using the Eudlo Creek crossing as a case study. It discusses how modelling approaches have progressively improved; driven by the innovation and enhancements in available data, guidelines, hardware and software. This paper also provides an introduction to new software advancements for 2019 that are set to revolutionise modelling into the future.