Northland transmission tower collapse report released

The Electricity Authority’s report into the collapse of a Northland transmission tower on 20 June 2024 that left 88,000 people without power has been released, Energy Minister Simeon Brown says.

“The report highlights that several key failures led to the transmission tower collapsing and that the economic impact for Northland was substantial. The report shows a range of estimates between $37.5 million and $80 million dollars in lost economic activity and that without distributed electricity generation, this figure would have been even higher.

“As expected, the report found that the removal of the nuts on the tower’s baseplates, which led to the towers collapse and the underlying factors that contributed to this, were entirely avoidable.

“More broadly, the report found an overreliance by Transpower on service providers to ensure that critical assets are maintained. It also found that identifiable risks were missed, including concerns that were raised internally.

“The report shows that concerns were raised by a senior engineer within Transpower in 2021 regarding a gap in the knowledge of maintenance crews undertaking foundation work, but that the recommendations for improvement by Transpower were not acted on.

“Transpower failing to act on these opportunities has led to terrible consequences for the people of Northland but there is also evidence that the removal of all nuts from more than one tower leg was not a one-off event.

“These are incredibly concerning findings, and the report identifies a number of recommendations that I expect Transpower will fully accept and act with urgency to address.”

The report recommends that Transpower review its policies on the escalation of service provider noncompliance events. It also calls for greater reporting on service providers so that the Transpower board and senior management can exercise effective governance and oversight.

The report also found that the restoration of power after the tower collapsed was carried out quickly, safely and efficiently, and highlights the importance of distributed generation.

“Distributed generation was able to meet 45 per cent of the peak demand, meaning that many customers could get up and running shortly after the tower collapse. Without distributed electricity generation, the economic cost to Northland would have been far greater. The Electricity Authority estimates that having access to that distributed electricity generation saved Northland consumers at least $26 million.

“The report recommends a review of the rules which limit the amount of power that can be generated by electricity distributors. The Government has already announced that we will be easing the restrictions that currently exist on EDBs so they can increase electricity generation and bolster regional resilience. Details will be confirmed by Cabinet later this year.

“The 26 recommendations in the report provide not only improvements in the oversight of maintenance work, training and assurance processes they also lay out a way to promote regional resilience,” said Brown.

Recommendations include:

• Transpower improving processes for maintenance work for baseplate refurbishment, and ensuring its contractors are more appropriately trained, monitored and compliant.
• Transpower should require its service providers to review and revise their work procedures for baseplate refurbishment to ensure they align with Transpower’s technical specifications.
• Transpower ensuring regular reporting and escalation of non-compliance by service providers to the Transpower’s Board so that the Board and senior management can exercise effective governance and oversight.
• The Electricity Authority developing options to amend the Electricity Code to allow for more regional resilience through distributors able to generate more on their own networks.

“Transmission towers are critical infrastructure and must be treated as such by all parties involved in managing and maintaining them.

“These recommendations are concrete steps for Transpower to improve its processes and contractor management to ensure that an event like this does not happen again. I will be writing to the Electricity Authority to express my expectation that the recommendations are implemented. The Electricity Authority will also be monitoring implementation of the recommendations.

“I would like to thank the review’s independent Chair Sarah Sinclair and the review team for its comprehensive report and those who provided information to inform the findings and recommendations,” said Brown.

Image credit: Miguel A. Padrinan