Transpower is being called on to act urgently after an investigation into the downed pylon found the power company had failed to act ahead its collapse. 

Almost 100,000 people across Northland were left without power after the pylon holding Transpower’s two 220-kilovolt (kV) transmission lines into Northland toppled over on a farm near Glorit, south of Wellsford on June 20. 

Today’s report included the already known finding that the pylon tipped after the removal of the nuts on the tower’s baseplates. 

The investigation, led by lawyer Sarah Sinclair, found several key failures including an “overreliance by Transpower on service providers to ensure that critical assets are maintained”, according to Energy Minister Simeon Brown. 

It also found a Transpower senior engineer in 2021 had raised concerns about a “gap in the knowledge of maintenance crews” but calls for improvement were not acted on by Transpower. 

“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,” Brown said. 

“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.” 

Within the 26 recommendations, Sinclair proposed Transpower improve processes for maintenance work for basplate refurbishment, ensure contractors were properly trained and regularly report on non-compliance from service providers. 

She also recommended the Electricity Authority assess options to “amend the Electricity Code to allow for more regional resilience through distributors able to generate more on their own network 

The estimated cost of the incident was between $37.5 million and $80m in lost economic activity. 

• Businesses want compensation as Transpower says too many nuts taken off in routine maintenance caused power cut
• 'Inconceivable' - bolts removed from pylon caused collapse, power outage
• Work continues to get Northland’s power supply back to full strength
• 'Unacceptable': Energy Minister on fallen pylon that cut power for 100,000 Northlanders

An earlier investigation, initiated by Transpower, found the Omexom crew working on the pylon responsible for its collapse. 

“The tower fell because the Omexom crew that was performing routine baseplate maintenance work did not follow Omexom’s standard practice and removed all of the nuts from three of the tower’s four legs.” 

The investigation found there was insufficient supervision of two less-experienced workers, who had not received any formal training for the work they were doing and were not certified by Omexom as competent for the tasks they completed unsupervised. 

The “inexperienced” team member who removed the nuts from the foundation legs was also not adequately supervised while performing the task, as the team leader was engaged in sandblasting work. 

Last month, Transpower acting chief executive John Clarke apologised to everyone affected by the resulting power cuts. 

Adam Pearse is a political reporter in the NZ Herald Press Gallery team, based at Parliament. He has worked for NZME since 2018, covering sport and health for the Northern Advocate in Whangārei before moving to the NZ Herald in Auckland, covering Covid-19 and crime.