In a first for flood recovery, a Black Hawk helicopter has been hauling 40 tonnes of boulders through the steep valleys of the Northern Rivers to repair a 100-year-old weir damaged by the 2022 floods and the aftermath of former Tropical Cyclone Alfred.
The long-line helicopter operation was used to airlift 24 basalt boulders to the historic Lavertys Gap Weir on Wilsons Creek, stabilising the eroded creek bank and preserving a key piece of Mullumbimby's heritage.
The $2.7 million weir repair, part of the million Northern Rivers Water and Wastewater Repair and Recovery Program, is led by the NSW Reconstruction Authority in collaboration with Byron Shire Council and delivered by NSW Public Works. The program is restoring critical water and wastewater infrastructure across flood-impacted communities.
A specialist marine contractor using tracked vehicles, floating barges and helicopters is carrying out the repairs. The works pose a complex logistical challenge requiring deep expertise.
The creek bank at the southern end of the 100-year-old weir wall suffered serious erosion during the floods. The damaged area has been carefully stabilised and reinforced with specialised geofabric, concrete and rock placement.
The two-tonne boulders, quarried outside Kyogle, were trucked to a staging site 400m from the weir. One rock at a time, the helicopter on Thursday and Friday last week airlifted its sling load to the weir over a total of four hours flying time.
The Black Hawk precision operation reduced the need to create new access tracks to the weir site and minimised environmental disturbance around the Wilsons Creek catchment.
An extension of Mullumbimby's emergency watermain connection to the Rous County Council regional water network was completed earlier this year under the same NSW Government program, which enabled the repair works to be completed without impacting the local water supply.
Thanks to careful planning, residents have experienced no disruption to water services, even as the weir has been drained. The repair works, which began in September, is expected to be completed by early January, depending on weather conditions.
Minister for Recovery Janelle Saffin said:
"You wouldn't normally call in a Black Hawk for reconstruction efforts but we had to think outside the box to ensure we could repair and protect a key piece of local history while ensuring Mullumbimby has a secure and reliable water supply for the future.
"The sight of a UH-60 Black Hawk helicopter placing giant boulders at the weir site was a joy to behold and shows what is possible when different levels of government work together in the best interests of a community in need of recovery support.
"The recovery of the Northern Rivers is long and complex but we are here with the community every step of the way."
NSW Reconstruction Authority Executive Director Reconstruction Graham Kennett said:
"This project highlights the practical on-the-ground recovery work the RA is delivering across the Northern Rivers."
NSW Public Works Project Manager Richard Greenhill said:
"This is a precision operation to stabilise Lavertys Gap Weir. By placing rock and engineered clay with precision, we're building a durable barrier that will protect the weir from erosion and withstand future flood events."
"We're addressing erosion that's undermining the weir wall itself which if left unchecked, could compromise the structure."
"This is a collaborative effort involving Council, state agencies, Traditional Owners, and the landholder, everyone has played a role in making this possible."
Byron Shire Mayor Sarah Ndiaye said:
"This is a complex project in a challenging location, and it is achieving results that will preserve the heritage fabric of Lavertys Gap Weir and secure its long-term integrity which are important to our community."
