NSW’s deadly one-in-100-years floods could have been slashed by two metres using dams, CSIRO finds

North Lismore artist and musician Jimmy Willing stands on the site of his studio, destroyed in the 2022 floods. Photograph: Christine Tontorf View image in fullscreen North Lismore artist and musician Jimmy Willing stands on the site of his studio, destroyed in the 2022 floods. Photograph: Christine Tontorf NSW’s deadly one-in-100-years floods could have been slashed by two metres using dams, CSIRO finds Governments have not committed to measures modelled in the report on Lismore’s 2022 floods, which led to the deaths of 13 people Get our breaking news email , free app or daily news podcast Building 10 new dams in New South Wales’s northern rivers could have reduced flood levels by up to two metres during devastating floods in 2022, but not enough to prevent a key levee overspilling, a report has found. The CSIRO report was released on Tuesday, four years after it was commissioned by the Morrison government following NSW’s one-in-100-years floods. The extensive flooding in the northern rivers between late February and early April 2022 led to the deaths of 13 people. More than 4,000 properties were left uninhabitable and another 10,849 were damaged. The total socioeconomic and structural damage is estimated at $16bn. The report found additional water detention dams would have reduced flooding by 2.1 metres, but would not have prevented the 3.8 metre over-topping of the Lismore CBD levee in February 2022. Sign up for the Breaking News Australia email The state and federal governments have not committed to delivering the measures modelled in the report as part of the $11.4m Northern Rivers Resilience Initiative (NRRI). On Tuesday, they announced a joint $3m feasibility study. While the report involved community engagement over several years, some Lismore residents have called for alternative measures, including relocating or establishing a second CBD above the flood level. CSIRO hydrologist Dr Jai Vaze, who led the report, said while implementing the measures in the report would likely be dependent on a business case, detailed architectural proposals and environmental approvals, as well as other flood resilience measures had already been implemented under $150 million in federal funding . “We can reduce the impact of large floods with strategically located detention and other flood mitigation measures across the entire Richmond river catchment,” he said of Tuesday’s findings. View image in fullscreen Michael Gooley, the operator of a family-run menswear business that has been in the Lismore CBD since 1957. Photograph: Christine Tondorf ‘Businesses have gone’ On Tuesday, Lismore residents had mixed reactions to the reports’ findings. Matthew Gooley, the operator of a family-run menswear business that has been in the Lismore CBD since 1957, and estimated it had lost “millions in stock” in floods, said the measures considered in the report would cost a “lot of money” but would be “amazing for Lismore”. “Take two metres off [2022 levels] and it goes bac