When a 275kV transmission tower supplying BHP's Olympic Dam operation was damaged during a storm event in October 2024, our teams needed to replace the structure while keeping power flowing to one of Australia's most critical industrial sites.
The customer
BHP operates Olympic Dam, one of Australia’s most significant mining and processing operations. Maintaining a reliable power supply is critical to supporting ongoing site operations and productivity.
The opportunity
In 2024, severe storms caused the collapse of two permanent 275kV transmission towers supplying power to Olympic Dam. Temporary transmission structures were rapidly installed to restore service while a permanent replacement solution was developed.
The project required the replacement of temporary transmission structures with new permanent towers while the line remained live, maintaining supply to the network.
Delivering this outcome required extensive engineering, detailed safety planning, specialist live-line expertise and close collaboration between all project stakeholders – the technical expertise and coordination on show was outstanding.
The solution
The Enerven Transmission Design Team took a forward-thinking approach from the outset of the emergency response in October 2024, designing the temporary emergency tower installation to allow the permanent replacement structure to be installed without interrupting power supply.
During the initial design phase, the team identified an opportunity to replace the existing guyed mast structures with freestanding tubular steel poles. This innovative solution meant the permanent restoration could be completed while the line remained energised, avoiding any isolation of the critical supply.
Further deign and modelling confirmed it would be possible, using carefully planned works by the highly skilled Glove and Barrier Lines team, to transfer all conductors live, thus eliminating the need for any shutdown of the 275 kV supply to Olympic Dam.
The temporary arrangement used two Lindsey towers to support the transmission conductors while the new permanent structure was constructed between them. Once complete, a specialised live-line crew safely transferred the conductors from the temporary towers onto the permanent structure, restoring the transmission line to its intended long-term configuration without a network outage.
Safety underpinned every stage of the project. Before construction began, civil works established a stable working platform and ensured safe access for personnel and equipment. During the live-line works, two cranes fitted with specialised high-voltage insulators were used to suspend the conductors, providing a critical engineering control that maintained the required clearances between the energised conductors and each crane’s earthing system. Two live-line elevated work platforms (EWPs), each subjected to rigorous pre-use dielectric testing, enabled crews to work safely in direct contact with the 275kV infrastructure. Field technicians also wore Faraday suits throughout the conductor transfer, protecting them from the effects of corona discharge and allowing barehand live-line work to be carried out safely.
The conductor transfer and tower changeover were successfully completed over approximately four days on site. Through detailed planning, technical innovation and close collaboration, the team delivered a safe and efficient outcome for BHP while maintaining supply to critical operations.
The project demonstrates Enerven’s ability to solve complex transmission infrastructure challenges using highly specialised live-line techniques. It is a capability that remains exceptionally rare within the Australian utility sector and showcases the depth of expertise across the business.
