THE Northern Rivers region’s Community Leaders Forum has welcomed the eagerly awaited state-of-the-art hydrodynamic model report for the Richmond River catchment.
While this is a very technical process, now it’s time for the community, particularly local councils, to be involved in charting a course towards better flood mitigation and adaptation for our region.
The model implementation report from the Northern Rivers Resilience Initiative (NRRI) was released publicly through the National Emergency Management Agency (NEMA) website yesterday (30 June 2025). It can be found here: https://www.nema.gov.au/our-work/resilience/northern-rivers-resilience-initiative
The Community Leader’s Forum has acknowledged that hydrodynamic modelling is the ‘Rolls Royce’ of flood modelling, and that the release of this report now lays the foundation for the model to be used in flood mitigation scenario analysis and testing possible flood mitigation strategies across the region to better protect communities and infrastructure.
The model (2D hydrodynamic model – MIKE21 FM) examines physical processes and creates a picture of the way water is moving in the river system. It uses data about rainfall, evaporation, soil and vegetation characteristics, LiDAR and Bathymetry datasets collected as part of NRRI project, and details of the landscape including the topography, streams, levees, and flow control structures such as bridges, culverts, and pipes.
The model was then validated by comparing model simulated flood inundation water levels against recorded data sets from five events in 2008, 2009, 2013, 2017 and 2022. This process reported a high degree of accuracy and seeks to demonstrate that the model is capable of reproducing flooding scenarios across the entire catchment.
The model should now be used to investigate a variety of possible future scenarios, including the changes in flooding associated with a changing climate.
This will help us to look at how we can better protect our communities and infrastructure from future flooding events, including testing structural and non-structural infrastructure options designed to mitigate flooding.
In the coming months, CSIRO has committed to work with NEMA to undertake NRRI stakeholder consultations to develop these Richmond River catchment scale flood mitigation scenarios, and then scenario analysis.
The Community Leaders Forum looks forward to engaging in this process.
The Forum includes Janelle Saffin MP (Lismore), Tamara Smith MP (Ballina), Geoff Provest MP (Tweed), and Richie Williamson MP (Clarence); Federal Member for Page Kevin Hogan, Federal Member for Richmond, Justine Elliot; Mayors Cr Steve Krieg (Lismore City), Cr Chris Cherry (Tweed Shire), Cr Danielle Mulholland (Kyogle), Cr Sarah Ndiaye (Byron Shire), Cr Sharon Cadwallader (Ballina Shire), Cr Robert Mustow (Richmond Valley) and Cr Ray Smith (Clarence Valley); NSW Aboriginal Land Council North Coast representative, Diane Randall, Business NSW Northern Rivers Regional Director, Jane Laverty, and Rous County Council CEO, Philip Rudd.
