Frederick Street cable upgrade
What we're doing
We're replacing major underground cables that we use to transport electricity from the National Grid to our network. The cables run from Transpower's Central Park substation off Brooklyn Road to our Frederick Street substation.
The Frederick Street substation is the main power hub for the area, supplying approximately 6,300 residential and 1,800 commercial properties via a downstream network of cables and smaller substations.
These substations supply electricity primarily to the Wellington suburbs of Te Aro, Mount Victoria and Mount Cook, and to some parts of Oriental Bay, Newtown and Wellington Central.
'Whakareri' means to prepare
As the city continues to grow, we're getting ready for the future by ensuring that our supply of electricity can meet demand. The new, modern cables will allow us to achieve this by increasing the amount of capacity available.
The new cables have also been designed to better withstand earthquakes, improving the resilience of our network and the electricity supply for consumers in these areas.
We’re also going to be installing new communications cables and upgrading our control and protection systems. These changes will all help increase the reliability of the area’s power supply and reduce the impact that power outages can bring.
How and when
Works along the new cable route will start in April 2021, which we expect to complete by September 2021. We’ll have around three separate crews working along the route to reduce the amount of time it takes for us to complete the project. As the crews progress, they’ll be digging up some roads and footpaths along the route to:
- Install new ducts and the new cables through these ducts.
- Connect lengths of cable together at three strategic locations (joint bays).
- Connect the cables to the substations at each end.
The crews will typically complete 5-20 metres of digging each day, installing ducts and filling in the dig sites as they go. So, not all of the route will be impacted at any one time.
We'll then complete work on the upgrades to our control and protection systems and put the new cables into service between December 2021 and February 2022.
We'll restore all affected roads and footpaths to their original state as soon as practical, and make sure everything's back to how it was once we're done.
Get in touch
If you can't find the information you're looking for in our FAQs section, please feel free to contact us.
News & Updates
Click here to get the latest information and see our interactive route map.
⚠️ Face-to-face visits are currently subject to COVID-19 Alert Level rules, but we're still able to organise a meeting if you'd like to discuss the project with us.

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