Network maintenance is a key part of keeping electricity flowing to the homes and businesses of North Canterbury. MainPower carries out network maintenance and upgrades year round. Below is a summary of some of our larger projects. For more information, please refer to our current Asset Management Plan.

Southbrook 66kV Substation upgrade

Overview: Rangiora and the surrounding area is experiencing significant growth, with new subdivisions and businesses springing up at a steady rate. The Southbrook Substation supplies this region. It currently operates at 33 kV. The purpose of this project is to upgrade and replace the substation to a higher capacity 66 kV / 11 kV 40MVA substation.

This project will future proof the network and allow us to continue providing a reliable supply of electricity to customers on our growing network.


  • design of the zone substation completed

  • system equipment procured

  • geotechnical works

  • compound and earthing works

  • other civil works

June 2021 update: Concrete poured for new switchroom foundations. Civil works continue to progress to schedule.

July 2021 update: The transformer foundations have been poured and switchroom construction is underway. Once complete, the switchroom will house 11kV switchboards and protection, as well as control and communications equipment.

October 2021 update: The two new transformers for the substation delivered and lifted onto their foundations.

MainPower NZ Ltd

New transformer being lifted onto foundations at Southbrook Substation in September 2021.

Hanmer Substation Line Upgrade

Overview: This project will provide a stronger and higher capacity supply into Hanmer Springs into the future. The line into Hanmer will be progressively upgraded from 33kV to 66kV. The work will involve pole replacements and line realignments,

August 2021 update: Scheduled for late 2021.

October 2021 update: Work is underway securing easements and completing other preparatory work. The focus for 2022 is to complete the agreed easements and to replace construction poles heading south from Lochiel Zone Substation.

Kippenberger Avenue Kiosk and Circuit Breaker

Overview: The Kippenberger Avenue kiosk project provides additional capacity from the new Southbrook zone substation into northern Rangiora. This will allow the end-of-life Rangiora North zone substation to be decommissioned. The Kippenberger Avenue circuit breaker project will improve network reliability in this area by separating the urban underground and rural overhead networks.

August 2021 update: This job is at the scoping and design stage and has been scheduled for October-November 2021.

October 2021 update: Design is now complete for both the kiosk and circuit breaker. The pole livening is scheduled for early November. The kiosk installation will be completed once resource consent comes through. This is expected this month.

Amberley North Regulator

Overview: During a fault event at either Amberley or McKenzies Road zone substations there is no full backup supply, due to voltage constraints. This Amberley North regulator project will improve our ability to back-feed during a fault by boosting the network voltage.

August 2021 update: The regulator has been ordered and the job has been scheduled for early 2022.

October 2021 update: Design is due to be completed during October.

Townsend Road Feeder

Overview: MainPower is currently constructing a new Southbrook zone substation to increase capacity into the Southbrook and Rangiora areas. This project's goal is to install a new cable down Todds road to provide a new feeder and capacity into western Rangiora.

August 2021 update: This job is at the scoping and design stage.

October 2021 update: Designs are now complete and consents received. Work is planned to begin in January 2022.

Amberley Rural Circuit Breaker

Overview: The Amberley area is currently supplied via an 11kV feeder which covers part of the urban township as well as part of the rural network outside of Amberley. This project installs a circuit breaker to minimise the impact of outages on the rural overhead network.

August 2021 update: This job is at the scoping and design stage.

October 2021 update: Design is now completed, with work underway to plan and schedule the job.

Pegasus Feeders

Overview: The Pegasus and Ravenswood subdivisions are continuing to grow, requiring more capacity from the network. This project extends two high capacity feeders into the Pegasus and Ravenswood networks to provide new capacity and an alternative back-feed supply.

October 2021 update: The work has been scheduled for February-March 2022.