Up to 46,000 people in Sydney could fail to evacuate if flooding comparable to that experienced in Lismore earlier this year strikes in the future, a report has warned.
The findings of an independent inquiry, led by NSW chief scientist and engineer Mary O'Kane and former police commissioner Mick Fuller, will be released today after being handed to NSW Premier Dominic Perrottet more than two weeks ago.
The inquiry will back plans to raise the Warragamba Dam wall, arguing it could save lives and homes by giving people more time to evacuate.
Bureau of Meteorology rejects suggestions it was unprepared for Northern Rivers NSW flood event
The Bureau of Meteorology has hit back at suggestions it is treated as a "nine-to-five business operation" after a report found it needs to review its data processes in the wake of the NSW floods.Five people died in the first flood event in the Northern Rivers on February 28, with evacuation orders for towns such as Lismore issued through the night as flood waters tore through the region.
The independent flood report estimates that by 2041 up to 46,000 people will live in high-risk flood zones in the Hawkesbury-Nepean Valley and could fail to evacuate in a one-in-1,000-year flood – like the one experienced in Lismore in February — and last seen in the area in the 1860s.
The report says that increasing the dam's capacity could reduce that risk by "holding back floodwaters" and "delaying peak flows".
It said increasing the capacity of Warragamba Dam could "provide a significant reduction in current risks to life and property" in the area.
The state government believes its plan to raise the dam's wall would mitigate floods by giving the dam about 14 metres of space above the current level to "hold back" extra water.
Flood-ravaged communities split amid backlash to temporary pod housing plan
Denise Lowe says opposition from North Coast residents to the installation of the pods in parks makes her feel "less essential than people being able to walk their dog".Lismore City Council has rejected a state government request to put the pods on sporting fields at Hepburn Park and plans to use a site in the hinterland village of Tregeagle have sparked a community backlash.
The plan has been criticised by environmental groups — who argue the Blue Mountains could lose its world heritage listing — and some First Nations people, who warn culturally significant sites would be destroyed.
Off the back of the report, the NSW government will also establish a Reconstruction Authority to oversee the rebuilding of housing and infrastructure in the wake of future disasters.
More than 6,000 homes were damaged in this year's floods, most of those in Lismore, with almost 1,500 of those severely damaged or destroyed.
Hundreds of people are still living in temporary accommodation in the flood devastated Northern Rivers region, with no certainty going forward.
The ABC understands a proposal to dismantle Resilience NSW, with is currently tasked with rebuilding flood destroyed communities, would be put to cabinet.
The new authority, which the government intends to have in place by Christmas, would be tasked with procuring and managing funds from government and philanthropic sources, and distributing it to affected communities.
It would also be in charge of disaster prevention in high-risk areas across the state.
The full report, which is expected to give communities in the Northern Rivers region more guidance on where and how they can rebuild their homes, will be released today.