Tarraleah Redevelopment Project

The redevelopment of Tarraleah hydropower scheme is part of Hydro Tasmania’s (HT) major projects, aiming to replace the existing aging water conveyance facilities, increase the hydropower scheme capacity and flexibility to align with the needs of the modern energy market.

PSM was engaged by HT as part of their integrated owners engineering team to provide engineering geological, hydrogeological and geotechnical design services. This included development of the project’s reference design for the following components:

• Surface pipeline foundations.
• Ground support design of cut slopes and portals.
• Primary support systems for the underground works including access, headrace and power tunnels.
• Primary support design for surge shaft and power station excavations.

Multi-disciplinary interfaces:

• Work ranging from engineering geological models, hydrogeology, landslide risk assessment, surface civil, tunnel excavations, digital engineering, contract risk and strategy in assisting the client in preparing a robust Request for Proposal (RFP).

Reference Design:

• Pressurised tunnel in variable ground conditions, large scale geological structures, groundwater leakage, poor ground with shallow cover.
• Slope instability associated with the portal face excavation.
• High inflow to power station box excavation below Nive River.
• Heavy loading on pipeline thrust blocks founded on soft alluvium.

Remote site and limited access.

A flexible “toolbox’ of robust ground support types to account for the variability in ground conditions.

Conducted optioneering studies and prepared technical specifications to reduce the contract risks, set up the minimum requirements and ensured the constructability of the reference design.

Automations in Building Information Modelling (BIM) to facilitate the development of 3D BIM models.

In tunnel grouting to control the operational water leakage and ensure long-term asset integrity.

Tarraleah Redevelopment Project is poised to revolutionise Tasmania's hydropower capabilities for the future energy market. By embedding extensive D&C delivery experience within the asset owner's engineering team, PSM identified geotechnical challenges and risks in the project. HT received a clear path forward, establishing project certainty and confidence in project costs and schedules.

Services: #Tunnelling #Hydropower #Geotechnical #Hydrogeology #Tarraleah #HydroTasmania