Powerlines beset by unassisted failures

Powerlines across Western Power’s network are failing at a rate of almost twice a day, while almost 20 of the utility’s ageing wood poles are toppling over every month.

An internal Government report has revealed in unprecedented detail the condition of Western Power’s
network, which sprawls from Geraldton in the north to Kalgoorlie in the east and Albany in the south.

The report shows that despite record levels of investment to fix longstanding problems, the State-owned utility’s equipment is failing regularly, with potentially dangerous consequences.

Poles and lines that fail can bring live electricity into contact with the ground and spark fires.

They can also represent a risk to anyone who touches or gets too close to them, or cause voltage fluctuations that can damage electronic equipment such as computers and televisions.

Western Power, which has been ordered by WA’s electricity safety watchdog to improve its wood pole network by December, said its “number one priority is the safety of our workforce and the community”.

Head of asset performance Mark Wilshusen said the utility was directing most of its $1.4 billion annual works program towards safety measures.

It had treated a record 90,000 of its 655,200 wood poles last year.

It also replaced 417km of overhead powerlines, upgraded more than 68,000 customer service connections and was confident it would meet the conditions of EnergySafety’s order.

According to the report, obtained under Freedom of Information laws, the distribution network — comprising hundreds of thousands of poles and lower voltage wires — was the most prone to “unassisted failures”, where equipment breaks because of age, lack of maintenance or poor installation.

There were almost 650 cases of unassisted distribution powerline failure in the 12 months to June 30 last year, including more than 170 in September 2013 alone.

There were also almost 150 instances of clashing conductors, where live overhead powerlines came into contact with each other because of “inadequate tension, regulation and separation”.

And the report shows that Western Power’s wood poles are falling over routinely, with almost 220 unassisted failures recorded in the year up to June last year.

Mr Wilshusen acknowledged an increase in the rate of un-assisted powerline failures, although he attributed part of it to a change in the definition of un-assisted failure and noted the September 2013 spike had been caused by storms.
He also pointed out the unassisted failure rate for wood poles had almost halved in the past two years, falling from 9.34 per 10,000 to 4.98 by December last year.