Homebush cable project

 

Ausgrid plans to lay new 33,000 Volt underground cables between substations in Pomeroy Street and Columbia Lane, Homebush to allow the Strathfield Subtransmission substation to be decommissioned. 

Project need

Ausgrid’s Strathfield Subtransmission Substation, located in Columbia Lane Homebush, is nearing the end of its serviceable life and is planned to be retired from service by the end of 2017. To allow this equipment to be retired, Ausgrid needs to install a new power supply for the Sydney Trains Strathfield site, which is next to our substation.

Ausgrid is planning to provide this supply by installing new 33,000 Volt underground electricity cables from our nearby Homebush Subtransmission Substation in Pomeroy Street to the Sydney Trains site. Once the new cables are installed and the Strathfield substation is retired from service, Ausgrid plans to retain the site as a storage yard. The existing 132,000 Volt overhead powerlines entering the site will remain in service.

Project planning overview

Ausgrid considers a number of factors when planning a cable route. These include:

  • public health and safety
  • availability of space around existing underground utility services
  • community impacts
  • environmental impacts
  • cost (minimising the impact on electricity bills)
  • technical feasibility
  • traffic considerations.

Planning the cable route

In planning cable routes there are a number of factors we consider, including the location of existing utility services under roads (such as power cables, gas and water mains) and ease of access for future cable maintenance.

Traffic authorities require Ausgrid to minimise work on major roads to avoid widespread disruption to motorists. Ausgrid also aims to minimise route length to lower the cost of construction and cables and to reduce community impacts.

Ausgrid also reviews the location of other local projects. We are liaising with WestConnex and Strathfield Council about their plans for the area.

Ausgrid has investigated and developed a proposed cable route (to view the proposed cable route please see the link to the right of page). For a large part of the route Ausgrid proposes to use an existing powerline easement through the Ismay, Allen Street and Arnott’s Reserves, with the remainder under local roads or undeveloped private land. 

While other route options are feasible, this route is preferred by Ausgrid as it:
• Passes the fewest number of homes and businesses
• Follows underneath the existing 132,000 Volt powerlines
• Reduces excavation in roads and community disturbance
• Allows for a faster construction process.

The other route options considered also can be viewed in the link to the right of page.


Project status

The project is currently in the planning stage. We are working with local residents and Strathfield Council to plan our works to ensure community impacts are minimised.

During the current stage of planning, Ausgrid encourages feedback on the proposed cable route by 31 March 2016.

Project approval process

Ausgrid is the approving authority for these works under the NSW Environmental Planning & Assessment Act. As part of the approval process, Ausgrid will conduct environmental assessments for this project, including the preparation of specialist studies and considering relevant input from the community, councils and other authorities.

Community consultation

Community consultation started in late 2015 with meetings with Strathfield Council and other stakeholders. Engagement with residents and businesses located along and around the cable route started in March 2016 and has included door knocks and delivery of newsletters to residents and businesses. Please find the first community newsletter in the publications section to the right.

Ausgrid welcomes questions or comments on the proposed route. We will consider all feedback before making a final decision on the cable route for construction. A map showing the alternative routes considered so far in planning the project are also available through the link on the right of this page.

Community feedback assists us to identify all potential issues and address them in our construction plans to minimise impacts as much as possible. The consultation process also allows people to discuss the project with the project team and find out more about the work in their area. Please get in touch to let us know your thoughts about the proposed route by 31 March 2016. 

If you have any questions or comments about the project, please contact us any time (see project contacts top right).


Electricity and health

Ausgrid welcomes questions about electric and magnetic fields (EMF) and whether it is safe to operate electricity cables in the community.

We take the health and safety of the community and our staff seriously and has planned this project in accordance with relevant health guidelines. Ausgrid will complete modelling of the predicted fields along the route and these results will be publicly available. However, based on the cable type and the location of the proposed cable route, we do not expect there to be any difference to background levels of EMF in local homes and businesses.

Reinstatement of roads and reserves

The majority of the proposed cable route is through local reserves. As each section of work is completed in these areas, the trenches will be backfilled and resurfaced with turf.

Following trenching and cable installation in roads, a temporary surface is laid over the trench so that the road can return to normal use. The temporary road surface remains in place until the cables have been pulled through the conduits (pipes) and tested. A period of time is required between work finishing and permanent restoration to allow for the road to settle and prevent cracks on the final surface. The excavated sections are then reinstated permanently in consultation with Strathfield Council by specialist road construction crews. Ausgrid will generally restore the trench area plus 300 milimetres either side, however each road is assessed on a case by case basis in consultation with Council.

What to expect during construction

As with any construction work, there would be some noise and dust, and temporary traffic, access and parking disruptions, which we will make every effort to keep to a minimum.

Construction generally will involve:

  • excavation of a 1.5 metre trench in the reserve or road and conduits (plastic pipes) laid in the trench to hold the new cables
  • steel plates placed over road trenches outside of working hours to maintain normal traffic flow
  • a temporary asphalt surface laid once road trenching is finished to enable normal road use to resume
  • construction will be completed progressively along the route. Depending on ground conditions, around 30 metres of work will be completed each day
  • excavation of underground joint bays every 500 metres to feed in and join the cables together 
  • at some locations bores may be used to cross rail and water ways 
  • permanent resurfacing to occur at the end of the project in consultation with Strathfield Council.