Planning is well underway for a major project to overhaul Unit 1 at our Wivenhoe Pumped Hydro Power Station, located west of Brisbane.

Queensland’s only pumped hydro power station has been generating lower-emission electricity for more than 40 years, and this major overhaul will ensure the station continues to operate safely and reliably for decades to come.

CleanCo owns and operates the 570MW power station, which can produce electricity for up to 10 hours when required to support the grid.

$48M investment over two years

In September 2024, the Queensland Treasurer, David Janetzki, announced a $48M investment in Wivenhoe Power Station over the next two years as part of the Electricity Maintenance Guarantee, a cornerstone of the Queensland Energy Roadmap. The Guarantee supports the ongoing safe, reliable and efficient operation of state-owned generation assets, helping to secure Queensland’s energy future as the system evolves. The Unit 1 overhaul forms part of that broader investment.

The overhaul is scheduled to begin Tuesday, 5 May 2026, bringing an additional 130 workers on site for 100 days and delivering a boost to the local economy, with an increase in demand of up to $1.3 million for local hospitality and accommodation services expected during the works.

A total of 19 specialist contractors will support the project, including Brisbane-based company Hydraulic Resolutions providing speciality hydraulic services, and Allied Rubber delivering rubber sealing solutions. The main labour component will be delivered by Downer, which was awarded the contract following a competitive tender process late last year.

Technical challenges

One of the most challenging aspects of the overhaul will be the bifurcate penstock recoating, which will involve constructing more than 40 tonnes of scaffolding inside Wivenhoe’s bifurcate — the Y-shaped junction where a single main water pipe from Splityard Creek Dam splits into two separate pipes feeding the station’s two Francis turbines.

The embedded guard gate tracks at Splityard Creek Dam, used by the plant’s high-pressure emergency intake gates, will also be maintained and upgraded.

Comprehensive maintenance of the Generator Circuit Breaker will restore the equipment to its original design specifications, supporting a further 10 to 15 years of reliable operation.

The overhaul will also include replacement of the main transformer bushings, with the high-voltage electrical insulators connecting the generator step-up transformer to the grid being swapped out as part of the works.

Specialised maintenance procedures, including generator inspections, slot wedge testing and life assessment activities, will also be undertaken to support the ongoing reliability and longevity of the station’s generator-motors.

Reduced road speed near power station

To support community safety, reduced speed limits will apply near the power station. Traffic controls will be in place – please follow directions.

CleanCo will share updates about the project as work progresses through our social media channels and website.