In a significant development for the 250MW Kidston Pumped Storage Hydro Project (K2-Hydro) in Queensland, Australia, Genex Power Limited has announced the successful completion of the Main Access Tunnel (MAT) for the underground works. This crucial milestone was achieved by the Engineering, Procurement, and Construction (EPC) Contractor – a McConnell Dowell and John Holland Group joint venture – marking a major step forward in the project's construction.

The MAT, serving as the permanent access point to the power station cavern, was excavated in high-quality rock conditions, meeting the required standards. This achievement ensures unimpeded access for lower bench excavation works and subsequent fit-out activities in the power station cavern, all accomplished within the established timeframe of the overall construction program.

Following an incident of water ingress in September 2022, Genex made the strategic decision to realign the MAT away from the zone of fractured material encountered in the original heading. Despite the additional length of 436m for the realigned MAT, this adjustment significantly reduced the overall risk associated with the underground works. Tunnelling works on the realigned MAT commenced in December 2022.

The completion of the MAT marks a major turning point in the underground works, effectively contributing to the de-risking of the entire Kidston Pumped Storage Hydro Project. The company affirms that the project remains on schedule for energization in the second half of 2024.

“The completion of the realigned Main Access Tunnel represents a major milestone for Genex and the Kidston Pumped Storage Hydro Project. We are extremely pleased with the way in which the Genex and EPC Contractor teams responded to the water ingress event last year, completing the redesign and recommencing production with minimal delay. This has limited the time and cost impacts of the water ingress event on the overall Project,” said Genex CEO Craig Francis. “[The] milestone is extremely significant, as it enables Genex and its stakeholders to draw a line under one of the material outstanding risk items for the underground works. Importantly it moves us one step closer toward commencing the power station fit-out works ahead of energisation later in 2024.”

Recently, Andritz Hydro, who is supplying the electro-mechanical equipment for the project, said that the last pieces of equipment arrived on site in October, paving the way for installation of the project’s components. 

Image courtesy McConnell Dowell