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Grid infrastructureNew ZealandEIR-2754

Transformer fire at Underwood substation near Lorneville, Southland, New Zealand

Nov 2021Published 4 Nov 2026Responsible editor: Chief Editor

MinorThermal / fireProvisionalNext update 5 Nov
Estimated damageEstimated by the register's adjusterHow? Know the real figure?
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supply cut for about •• daysShown in the record →Full estimate
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Companies named in the reporting of this entry (being named is not a finding of fault): PowerNet

What happened

A transformer at the Underwood substation, near Lorneville in Southland, caught fire at about 11.30am on 7 November 2021. Fire and Emergency New Zealand said smoke was seen coming from the site, and crews from Invercargill and Wallacetown attended with PowerNet staff. Once the power was isolated, firefighters used foam to extinguish the oil-filled transformer fire, which was out by 12.35pm. Environment Southland was notified because the smoke from the oil fire was thick and black. Power was lost for a time to nearby areas including Lorneville and Wallacetown, and to the nearby freezing works. PowerNet said supply had been restored to most customers by 1pm.

Contributing factors

The source does not state the cause. PowerNet said the cause of the outage was being investigated. Fire and Emergency New Zealand noted that oil-filled transformer fires are difficult to extinguish.

Lessons learned

  1. Oil-filled transformer fires need enough extinguishing foam to be ready before attack starts, because running out lets the fire restart.
  2. Isolating the equipment with the network operator before firefighting was the sequence used in this incident.
  3. Oil fires producing heavy smoke should prompt early notification of environmental regulators.

More lessons on fire suppression and firefighting, emergency response and public communication, from every incident on the register.

Source

odt.co.nz

Published 2026-11-04. Written from public reporting. Descriptive, not investigative. See the data accuracy disclaimer.

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