Earlwood to Summer Hill cable project

Earlwood to Summer Hill cable project - a similar cable project 
Ausgrid is planning to replace underground electricity cables that run between our substations at Earlwood and Summer Hill. The existing 33,000 volt cables are nearing the end of their service life and need to be replaced so Ausgrid can maintain a safe and reliable power supply to the area in the future.

Project need

The existing 33,000 volt underground cables are nearing the end of their service life and are to be replaced.  The cables are connected to a substation at Summer Hill (known as Dulwich Hill zone substation) which Ausgrid is also planning to replace with a new facility next door.

The existing substation and cables have been in service since 1966 and are a key part of the electricity network supplying power to Summer Hill and surrounding suburbs. Ausgrid constantly monitors its infrastructure and has identified the need to replace the cables and substation in the coming years before they become unreliable.

Planning cable projects

As Ausgrid plans this project, there area number of factors to consider, including:

  • community impacts
  • availability of space around existing utility services
  • environmental and heritage impacts
  • cost (minimising the impact on electricity bills)
  • technical feasibility
  • traffic impacts
  • crossing Cooks River and the Bankstown railway line.

Project status

Key project dates

Project approval process and environmental assessment

Ausgrid is responsible for assessing and approving works under the Earlwood to Summer Hill cable project. This process includes preparation of an environmental assessment (Review of Environmental Factors or REF). The REF includes a range of specialist studies and input from the community, councils and other authorities.

The REF was on exhibition for comment from Monday 22 May to Monday 19 June 2017 and Ausgrid encouraged feedback electronically, by email, phone or directly at a drop in session during this time. The REF was available at the Emanuel Tsardoulias Community Library in Dulwich Hill, Ausgrid's office at 570 George Street, Sydney and via the link at the top right hand side of this page (where it can still be viewed). A drop in session was also held at the Canterbury-Hurlstone Park RSL Club on Tuesday 6 June 2017 for interested community to attend and ask questions.

While Ausgrid received no formal submissions, there were enquiries and feedback was provided directly to the project team during this time. The project team are now considering all feedback received as part of the process to assess the project for approval based on information contained in the REF  and other relevant documents. Subject to project approval, construction is planned to start in the second half of 2017 and be completed by the end of 2019.

If you have submitted feedback or expressed interest in the project we will be in touch to let you know when the environmental assessment is complete. 


Community engagement

Initially Ausgrid's planning focused on potential ways to cross the Cooks River and the Bankstown Line railway as this would have a significant influence on the potential cable routes. Potential options for these crossings included boring underneath the river or attaching the cables to existing bridge structures. A range of initial route options were developed for further investigation and Ausgrid began consultation with the then Canterbury Council (now Canterbury-Bankstown Council).

Ausgrid investigated these routes with consideration of a range of factors (see the 'Planning cable projects' section above) and further consulted with Council. Following this process, Ausgrid refined the potential routes to a number of feasible options for community feedback.

On 21 June and 23 June, 2016, Ausgrid held two information sessions, one at the Canterbury Hurlstone Park RSL Club and the other at the Ashfield Civic Centre, to seek local information and community feedback on potential cable routes. Interested community members were invited to the workshop directly through newsletters, social media and advertisements in local newspapers.  At the community information sessions, members of the project team gave two presentations -  on project need and what to expect during construction of a typical underground 33,000 Volt cable project.

 A summary of feedback received at the information sessions and via direct feedback to Ausgrid after the sessions was prepared and this  feedback was considered by the project team as part of the process to refine the options to a proposed route and to plan the project to minimise impacts during construction. The presentations and a summary of the feedback from the sessions and from direct contact with Ausgrid can be viewed in the community information and presentations section.

Ausgrid then sought comments on the project's environmental assessment ( REF) which was on exhibition from Monday 22 May to Monday 19 June 2017.  The REF was available at the Emanuel Tsardoulias Community Library in Dulwich Hill, Ausgrid's office at 570 George Street, Sydney and online). A drop in session was also held at the Canterbury-Hurlstone Park RSL Club on Tuesday 6 June 2017 for interested community to attend and ask questions. While Ausgrid received no formal submissions, feedback from the community was provided directly to the project team. All feedback is now being considered as part of the process to assess the project for approval based on information contained in the REF  and other relevant documents.

Ausgrid welcomes feedback throughout all stages of the project.

What to expect during construction

Like any construction work, the project would involve noise and dust, and temporary traffic and parking disruptions, which we would work to reduce as much as possible. Any potential impacts are assessed as part of an environmental assessment (known as a Review of Environmental Factors or REF) and measures would  be put in place to minimise impacts on the local environment.Click here to view an information graphic showing the stages of cable laying. Construction would include:

  • digging trenches, typically 800mm wide, to lay conduits (plastic pipes) to hold the new cables
  • filling trenches and resurfacing the area temporarily
  • trenching and temporary restoration of affected areas takes about three days outside each property depending on ground and weather conditions
  • excavating underground joint bays every approximately 900 metres along the route in the road to feed in and join sections of cables together
  • feeding in and joining the sections of cables takes two to four months to complete at the joint bays
  • work on the joint bays usually occurs in distinct stages
  • final restoration of affected roads and other areas in consultation with council.