132 KV Powerline Relocation Project

Frequently Asked Questions 

Background and details

The Molonglo 132 kilovolt (kV) Powerline Relocation Project will see the replacement of the existing overhead high voltage electricity transmission lines that transect the Molonglo 3 urban development area, including across the new suburb of Whitlam, with underground electrical transmission lines. An example of the overhead powerlines to be removed is shown in Figure 1.

Figure 1: Example of overhead tower/lines to be removed.

The project is being delivered by the Suburban Land Agency in partnership with Evoenergy. Stage 1 of project is the replacement of the existing overhead Holt to Woden powerlines into underground conduits and pits, and the provision of conduits and pits for Stage 2. The second stage of the works, which is expected to occur around 2030, involves the replacement of the overhead Civic to Woden line into the underground conduits and pits constructed in Stage 1.

Why are we doing this?

The underground electrical transmission line project will provide a positive community benefit, with the removal of unsightly infrastructure from the landscape and a better urban Molonglo outcome. Boundary Road at the Arboretum will be sealed enabling a more accessible road for the public, as well as the horticultural team who maintain over 44,000 rare, endangered and symbolic trees.

What is happening?

Starting in April 2022, the first part of works will occur with fencing removal, installation of temporary fencing, topsoil stripping and maintenance access track preparation. Work will be undertaken between 7am and 5pm on weekdays with some work on Saturdays between 7am and 1pm.

Other works include trenching, under-boring, cable hauling, maintenance access track construction, reinstatement of fencing and dryland grass, and road sealing. This work is expected to be undertaken onsite along Boundary Road at the National Arboretum until late 2022.

The works area will be fenced to ensure community safety. Following construction, the existing overhead powerlines and towers, which run from Whitlam to the Tuggeranong Parkway at the Molonglo River, will be removed. Construction noise impacts, above the general highway traffic, should be minimal, and dust suppression practices will be in place.

Where will this occur?

Affected areas for this work will impact public access points within the National Arboretum and adjacent reserve areas. Portions of access trails including Boundary Road will be closed to allow these works to be delivered safely. These closures will be minimised and alternative routes will be provided where practical. Please see the map below that shows the area of works.

What is the alignment?

The alignment for the new underground cables will run along the western edge of Whitlam to William Hovell Drive, head east along William Hovell Drive to Coulter Drive and then head south down the future urban edge of Molonglo (adjacent to the Arboretum) before reconnecting to the existing overhead transmission line on the eastern side of the Tuggeranong Parkway, near the Molonglo River.  

Are underground cables safe?

Yes, they will meet the highest electrical safety standards, similar to underground powerline projects in other states and territories. The electrical cables will be installed within conduits and electrical pits, which are located outside the urban edge within generous easements along the full length of the alignment.  The lines are also well away from where homes will be built in the future. The works will be designed and constructed to meet Evoenergy’s requirements. 

Will the work have any environmental or heritage impact?

The works will have minimal environmental impact as they occur within the future Molonglo Urban Development area which has a number of environmental clearances already in place.  The alignment also avoids all Molonglo environmental offset areas.  The alignment has been developed in conjunction with the Environment, Planning and Sustainable Development Directorate and minimises impact on existing trees and vegetation.  The full alignment has also undergone a heritage assessment.

Will this work have any impact on residents of Whitlam, Denman Prospect and other suburbs?

The work will have little impact on new residents of Whitlam, Denman Prospect or other suburbs.  The trenching and cable installation works will occur on the outside urban edge of Whitlam, having minimal on residents. The decommissioning of the towers will occur through parts of future stages of Whitlam, well before new residents commence building on their blocks. In the long term the project will provide a positive benefit on the community, with the removal of unsightly infrastructure from the landscape. The associated maintenance tracks will also provide access vehicles to respond to bushfires.  

Is the Molonglo Zone Substation part of this project?

Evoenergy are currently constructing a new substation near the intersection of William Hovell Drive and Coulter Drive. The 132kV Powerline Relocation Project was designed to accommodate the future substation at this location, however the projects are being delivered separately. Further information is available from Evoenergy here.