More than two years after devastating floods claimed 13 lives in northern New South Wales, a new scientific report has found that building 10 new dams in the region could have dramatically reduced flood levels by up to two metres. This insight offers a stark perspective on the potential for strategic infrastructure to mitigate the impact of future extreme weather events.
Released this week, the CSIRO report, commissioned by the former Morrison government in the wake of the 2022 disaster, highlights the complex interplay between human intervention and natural forces. While the proposed dams would have significantly lessened the severity of the floods, they would not have been enough to prevent Lismore's critical levee from being overtopped, underscoring the immense scale of the disaster.
The Two-Metre Difference
The scientific modelling undertaken by the CSIRO paints a compelling picture of what might have been. By strategically placing 10 new dams across the northern rivers catchment, floodwaters in Lismore could have been reduced by up to two metres. To put this into perspective, a two-metre reduction could mean the difference between a house being inundated to the roofline and floodwaters reaching only the ground floor, or even remaining almost entirely dry. This substantial reduction has reignited calls for governments to seriously consider and commit to large-scale infrastructure projects as part of a comprehensive flood mitigation strategy. The Guardian Australia reported on the report's key findings, drawing attention to the significant potential impact of these unbuilt dams.
A Decade of Delays and Unanswered Questions
The release of the CSIRO report, four years after its commissioning, raises questions about the pace of government response to natural disaster preparedness. The 2022 floods, often described as a 'one-in-100-years' event, exposed critical vulnerabilities in the region's flood defences and emergency response. While the report was initially commissioned to explore dam options, governments have yet to commit to the specific measures modelled within its pages. The delay in action, particularly given the recurrent nature of severe weather events in Australia, has drawn criticism from community groups and environmental advocates alike, who are demanding more proactive measures to protect lives and property.
Beyond Dams: A Holistic Approach to Resilience
While the CSIRO report focuses on the significant potential of dam construction, experts caution that a holistic approach to flood resilience extends beyond just infrastructure projects. Land use planning, improved early warning systems, voluntary house buy-backs, and community education are all crucial components of a multifaceted strategy. The 2022 floods tragically demonstrated that even with a levee, the sheer volume of water overwhelmed existing protections. Therefore, while additional dams offer a compelling solution for reducing peak flood heights, their implementation must be part of a broader, integrated plan that considers the unique hydrological characteristics of the northern rivers region and the socio-economic impacts on its communities. The cost of such infrastructure projects, potentially running into hundreds of millions or even billions of Australian dollars, would also need careful consideration against the escalating costs of disaster recovery.
Future-Proofing Our Communities
As climate change continues to influence weather patterns, leading to more frequent and intense rainfall events, the findings of the CSIRO report serve as a powerful reminder of the urgent need for long-term strategies. The debate over dam construction in environmentally sensitive areas is often fraught with complexities, balancing ecological concerns with human safety. However, the report’s unequivocal findings regarding the potential reduction in flood levels demand serious consideration from both state and federal governments. The tragic loss of life and billions of dollars in damages incurred during the 2022 floods underscore the imperative to invest in robust, scientifically-backed solutions to future-proof communities against the growing threat of extreme weather.
