Powerline Maintenance And Bushfires  

The Age has an article on the role power line failures had in last summer's Victorian bushfires - Stakes rise as role of power lines shifts to fore.

The Bushfires Royal Commission has scrutinised the stay-or-go policy, failures in communication, the need for safe places and the role of bunkers - but its examination of the role of power lines in the February 7 fires, which killed 173 people, has attracted much less publicity.

Five fires - half the total - were started by electricity lines. The commission has looked at four - Coleraine, Horsham, Pomborneit and Beechworth - and raised serious questions about the safety of the infrastructure and the regularity of inspections. But the main event will come next month, when the cause of the deadly Kilmore East-Kinglake fire will be examined.

This fire, too, was caused by a single-wire power line. The Sunday Age reported in August that police photographs indicated this line was seriously weakened, rusty and repaired numerous times. Evidence suggests that it broke about 11.30am in 60 to 80 km/h winds, sparked, and caused a fire that would go on to kill 121 people. ...

Both the Coleraine and Horsham wires were erected in 1962, as the then-State Electricity Commission used Single Wire Earth Return (SWER) lines, the cheapest possible technology available, to take power to the furthest reaches of the state.

In the mid-1990s, the power companies decided that inspecting their assets every three years was expensive and unnecessary. They told the safety regulator they would be moving to five-yearly inspections. The regulator agreed, subject to auditing for safety. That decision has now been questioned in the royal commission. In Coleraine, the wire that started the fire had not been inspected for four years and five months, and the Horsham line had not been inspected for four years and seven months. Both had detatched from their poles on other occasions in recent years.