MAYORAL MINUTE NO 16/2022
CALLING FOR THE WARRAGAMBA DAM WALL TO BE RAISED
12 JULY 2022
Councillors,
Residents of The Hills have endured yet another major flood. This flood in particular was the highest that I and many local residents have seen and it was marked by how fast the river levels rose and how quickly properties were inundated.
For some, it is the fourth major flood in 16 months. For our impacted residents, this means having to watch their homes and businesses being severely damaged again and having to go through the clean-up process once more. It is the worst-case scenario, and our residents have had enough of going through this cycle.
Business as usual is not an option. Our residents along the river need greater mitigation from these major floods.
That is why the Mayor of Hawkesbury City Council, Pat Conolly and I have been publicly advocating over the last week that the Warragamba Dam wall be raised as a matter of urgency.
This follows on from long held positions of both Council’s that the Warragamba Dam be raised.
By doing this, we could significantly reduce the risk to life downstream and lessen flood damage by 75 per cent.
Warragamba Dam was only ever built for water storage purposes and not for flood mitigation.
The 2017 NSW Infrastructure Report “Resilient Valley, Resilient Communities” outlined that the raising of the Warragamba Dam wall was the infrastructure option with the highest benefit in reducing flooding of the Hawkesbury-Nepean River. A number of options were reconsidered in the 2021 Environmental Impact Statement (EIS), including raising the Dam wall. This option was considered as offering the most benefit towards meeting the Flood Strategy’s risk reduction objectives and KPIs
As per the 2021 EIS, raising the Dam wall by 14m is predicted to provide significant flood mitigation to residents and businesses along the river. With the presence of the 14m Dam wall, the March 2021 flood levels are predicted to have been reduced by 5m at Penrith and 3.6m in Windsor. 80 per cent of flood impacted properties in the March 2021 flood are predicted not to have been impacted if the Dam wall was in place. Further to this, the presence of a 14m wall is predicted to reduce the estimated damage bill from $3 billion to $400 million in a 1 in 100 year flood. In a flood that is the height of the 1867 disaster, it is estimated that raising the Dam wall would save 7,000 homes.
It is important that Council support our residents and businesses to give them greater mitigation against floods impacting their homes and businesses. That is why this week, I have appeared on 2GB, Channel 7, Channel 9 and Sky News to advocate for our community.
There must be a greater focus on flood mitigation and not simply on recovery. The raising of Warragamba Dam for flood mitigation has been discussed for decades and the process has been bogged down by indecision and bureaucracy. The time has come for a clear commitment from the State Government to proceed with this project, and to do so without Federal support if necessary.
Accordingly, I move that MOTION:
1. This Mayoral Minute be received.
2. Council write to the Premier of NSW and the Prime Minister to advocate for the raising of the Warragamba Dam wall to provide greater flood mitigation.
Dr Peter Gangemi MAYOR