In order to advancing the underground works on the Borumba pumped hydro energy project, Queensland Hydro is calling for Expressions of Interest.
Using controlled blast and drilling methods, the tunnel drilling package will involve the digging of soil and rock, which is better than TBM to form a D-shaped tunnel leading to the proposed site of the underground powerhouse cavern.
Considering that a detailed understanding of ground conditions is required to inform detailed design of the project and how it is best delivered, this tunneling is going to complement surface geological investigations.
Following completion, the excavated tunnel will be repurposed to become a permanent cable tunnel and the works is slated to be accompanied by the required environmental approvals.
The EOI release follows the co-ordinator-general’s coordinated project declaration on October 12, signaling the start of the assessment of social, economic and environmental matters before the Borumba Project’s Main Works can begin.
Construction of a new upper reservoir, as well as a new dam wall to replace the existing Borumba Dam wall and increase Lake Borumba’s storage capacity from 46 to 224 gigalitres, are the contents of this project with A$14.2bn (£7.4bn) value. It will include an underground power station and pump turbines, and underground tunnels to transfer water between the upper and lower reservoirs, as well as cable and access tunnels.