POWERCOR has revealed the power pole which started the Garvoc St Patrick’s Day fire was 50 years old, and metal supports to strengthen it had been in place for the past 20 years.
When asked if Powercor was sorry about the fires, general manager electricity networks Steven Neave said “absolutely, absolutely”.
“On a day like that, it’s the thing that keeps you up,” he said.
“It’s not comfortable ... We are just really thankful that there has been no fatalities.”
Victoria police found the four main fires at Gazette, Terang, Camperdown and Garvoc all started due to electrical assets.
A “rotten” pole with metal support stakes on Jack Kenna’s farm at The Sister’s broke, igniting the blaze.
Mr Neave said Powercor accepted Victoria police and Emergency Management Victoria’s findings into the causes of the fires, despite it telling The Standard last week the pole had been deemed to be in a “good condition” only four months ago.
“The question really now is why. We are fully co-operating. We accept it has broken. It shouldn’t have broken,” he said.
“Was it due to extreme conditions or was there other issues where the pole actually wasn’t fit at that point in time?”
Mr Neave said inspections of poles occurred every two-and-a-half years, which was ahead of the regulations of three years.
“The Garvoc pole was last inspected in November 2017,” he said.
“The previous inspection was in 2015.”
Mr Neave said Powercor could “usually get 50, 60, 70 years’ life out of a pole”.
He said the two metal supports on either side of the pole had been there for about 20 years.
“They are a common and widely used technique to strengthen a pole,” he said.
“They are not temporary. They are a standard practice used for the life of the asset.”
He said across the Powercor network there was 400,000 timber poles, and about 30,000 had metal supports.
“An asset inspector would have inspected the pole and have ascertained the pole required some work,” he said.
“We would look at our options. One is to remove the pole and another is to put in the stakes. It’s a good option as there is no customer impact.”
He said staking the pole could restore it to be stronger than when it was originally installed.
He said concrete and metal poles were not commonly used in the south-west
“Concrete poles aren’t necessarily the solution,” he said.
“They are good for bushfire prevention but the concrete poles are hollow and they have a steel cage or core and in the south-west they suffer from the salt in the soil and they rust so we don’t tend to use them as much.”
He said Powercor would co-operate if there was an inquiry, as suggested by Wannon MP Dan Tehan.
Mr Neave said routine inspections of poles around the Terang fire area were completed in February 2017.
He said as police had concluded, conductors had clashed, starting that blaze.
“We basically had conductors coming in contact where they shouldn’t be coming in contact,” he said.
“That has started the fire. Again we accept that conclusion, and again it comes to the question of why. How did that come to be? Our investigations are still underway.”
Mr Neave said Powercor inspected vegetation in high bushfire risk areas such as the south-west every year.
“We will fly the lines using what is known as LiDAR (Light Detection and Ranging Measurement) technology, which is basically laser technology. It’s either via a fixed wing plane or a helicopter,” he said.
“We are about to start that program again to identify any vegetation which is within what we call the clearance space. If we do find any vegetation then we have an activity to go and cut that vegetation before the summer season starts.”
He said the clearance space depended on a number of factors including voltage and the length of the line.
The bushfire at Gazette, which burnt more than 3000 hectares and destroyed three homes, started due to a tree from a blue gum plantation falling onto power lines.
Mr Neave said in that area there was a clearance zone of 20 meters required from the trees to the power lines.
He said the tree that came down was outside the zone.
“It looks to be a healthy tree as well, it wasn’t a tree that was deteriorated or dying in any way,” he said.
Mr Neave said after the Black Saturday Royal Commission there were seven recommendations for the industry.
He said five had been implemented and two were underway. He said they were in line with the regulatory timelines.
He said the most significant recommendation out of the royal commission was still being implemented.
It centers around rapid earth fault limiters, which is to designed to detect faults such as a tree coming onto a line. It then neutralises the fault current and takes the energy out of the fault down to a point where it won’t ignite vegetation.
The technology has not been implemented in the region yet. Mr Neave said it was expected in Camperdown in the coming months, Colac by the end of the year and in Koroit and Terang by 2022.
He said there were no plans to fast-track it for the region.
“It is a very complex piece of technology,” he said.
“It’s already on a fairly accelerated program.”
He said most of the rural network had above ground lines, with 70,000 kilometers of overhead conductors and 5000 kilometers under ground cable. He said 200 kilometers of overhead line had been replaced with 260 kilometers underground after the Black Saturday recommendations. The majority of that has been in the Colac-Otway Shire area.
He said he wasn’t sure if the south-west would be targeted for underground cables, adding further bushfire modelling needed to be completed.
Mr Neave said Powercor had met the reclose function disablity recommendation that arose from the royal commission.
“That’s done so we don’t re-energise potentially into a bushfire-prone area,” he said.
“We now have the ability to disable the reclose functions on total fire ban days remotely.”
He said it had been operating “as it should have been” on Saturday when the fires started.
When asked why the lines had clashed and arced on that day, Mr Neave said “that’s what we don’t know”.
“It certainly wasn’t from a reclose,” he said.
“About 70 per cent of all our faults are temporary. The reclose function then will try to re-energise the line and 70 per cent of the time it is okay and that’s great for our customers because besides having to reset their clocks there is not a lot of impact.
“For the other 30 per cent of the time where it’s a permanent fault it will then open again and stay open and we obviously need to go on patrol and find the fault and do the repairs.
“Disabling reclose on the bushfire day doesn’t limit the ability for that primary fault to start, it just means we don’t re-energise back into the fault. So there’s a reliability trade-off with more customers impacted, but obviously our primary concern on total fire ban days is to make sure we are not doing that could potentially start fires.”
When asked what Powercor could do to ensure the fires didn’t happen again, Mr Neave said: “That’s really a tough one.”
“We have 70,000 kilometers of overhead line out there,” he said.
“The asset management practices that we have in place – we are continuing to refine and make sure they are world’s best practice. But there are a lot of assets out there which unfortunately wires will come down whether that’s due to extreme weather conditions or other things outside or control such as cars impacting poles and they potentially cause fires. It’s a really difficult one to eliminate.”
He said Powercor could try to limit those things happening in the first place or implement technology to mitigate the extent of the fire occurring.
“We continue to seek funding to do work beyond the recommendations of the royal commission,” he said.
He said the fires had been “devastating” for the community.
“We are impacted by these fires as well,” he said.
“We’ve got field crews down there and impacted regions. Many of them actually volunteer and work for the CFA.”
“All we can do at this stage is fully co-operate with the investigations. We are keen to reach out to our customers.”
Mr Neave said Powercor had professional loss assessors on the ground in the south-west to assist people with assessing their damages.