Burnie–Port Latta–Smithton 110 kV transmission line upgrade
Client: TasNetworks
Location: Tasmania, Australia
Date: 2023 - ongoing
Services: pole arrangement design, wire attachment point loads, foundation design, construction support
Concept and detailed design to help keep Tasmania’s transmission network safe, efficient and reliable
Description
Reliable, flexible and resilient transmission networks are crucial components of Australia’s energy transition. In Tasmania, aging assets that were built through the many decades of hydropower expansion must be maintained and upgraded to support existing needs as well as enable more new renewable energy generation and a more flexible energy system.
TasNetworks’s Burnie–Port Latta–Smithton transmission line is a key part of Tasmania’s power infrastructure, connecting customers across 71 km in the north-west of the state, including the communities of Smithton and Stanley.
Originally constructed in 1949, the line has been exposed to decades of harsh coastal conditions. Over time, corrosion can develop, which can weaken a tower – so for reliable service and ongoing safety, deteriorated towers ultimately need refurbishment or replacement.
Solution
When TasNetworks identified a number of transmission towers with corrosion issues, the towers were scheduled for replacement with new double-circuit steel poles. The new double-circuit suspension and strain pole designs would need to suit the requirements of these lines as well as other 110 kV lines in the system.
Entura reviewed the existing loads and insulator swings in each transmission line and completed the preliminary and detailed design for replacement of the towers along the corridor.
This included determining the suitable dimensions for the new suspension and strain poles and how to meet the site-specific requirements for the proposed locations.
We used PLS CADD and PLS-Pole throughout the design process, which was performed in accordance with the required standard.
Outcome
TasNetworks is now progressively delivering the Burnie–Port Latta–Smithton upgrade program, replacing aging infrastructure with modern structures aligned with contemporary engineering standards and designed for long service life in challenging coastal conditions.
The project to upgrade all 279 structures is expected to continue over a decade, ensuring north-west Tasmania’s transmission infrastructure is robust, adaptable and ready to support the state’s evolving energy future.
The designs also incorporate additional height and strength to better manage clearances and dynamic loading, while enabling future network upgrades (such as higher-capacity conductors) without requiring further major structural changes.
We are proud to have played a significant role in futureproofing the safe, reliable, efficient and compliant transmission and distribution of electricity to the Tasmanian community for generations to come.
