ActewAGL carried out helicopter inspections of overhead powerlines across its network during February, giving the utility an overall view of the state of its network. The helicopter patrols are an essential part of ActewAGL’s vegetation management and asset management program.
The patrols inspected for vegetation encroaching on powerlines and flew at approximately 110150 metres in rural areas and above 310 metres in urban areas, with minimal hovering.
The helicopter used Light Detection and Ranging (LiDAR) remote sensing technology to determine the distance between powerlines and vegetation.
Vegetation deemed too close to powerlines during the patrols are being prioritised for cutting by ActewAGL’s authorised service providers in rural areas. In urban areas, notifications have been sent to customers or the ACT Government, depending on where trees are located.
The helicopter also took high resolution pole top images in high bushfire prone (rural) areas to assess the pole top condition and prioritise ActewAGL’s preventative maintenance regimes.
ActewAGL Manager Works Delivery Clinton McAlister said, “The helicopter patrol is a significant part of our overall network maintenance program and bushfire mitigation strategy.
“Trees and vegetation growing too close to powerlines can cause blackouts and create safety hazards such as grass fires and bushfires. Trees and vegetation can also restrict access, preventing essential maintenance from being carried out.”
Residents urged to monitor property
The patrols revealed that trees are too close to powerlines in many parts of the nation’s capital; and ActewAGL is encouraging residents to continue to monitor vegetation on their property.
Good vegetation management standards see that:
- Trees are 1.5m clear of powerlines. If they are already too close, residents should contact an accredited tree surgeon.
- There is 1.5m of clearance in all directions around the base of poles, meters, substations and mini pillars.
“ActewAGL helicopters were flying throughout February to inspect vegetation around our poles and wires. This year the helicopter was in the air for around 37 hours and covered 1,793km across most rural and urban areas in the ACT,” said Mr McAlister.
“We were able to identify vegetation encroaching on powerlines that we would not be able to see from the ground. We are now working with landowners and occupiers to ensure the safety of our community and the network.”
Landowners and occupiers are responsible for keeping a clearance of 1.5 metres around powerlines; but Mr McAlister noted that residents shouldn’t attempt to trim branches themselves. The task should only be carried out by an accredited tree surgeon.
Trees touching powerlines can create blackouts and increase risk of fires and electric shock. In windy weather, trees can fall and bring down live electrical wires, creating a dangerous safety hazard and interrupting power supply.
ActewAGL has been using helicopters for inspection since 1979, when the utility first borrowed a helicopter to inspect a large portion of its network.
“Since then we’ve been using helicopters in a few different ways,” said Mr McAlister.
“Helicopter patrols are the most accurate and effective way of detecting encroachments between the vegetation and our poles and wires.
“It allows us to look at the top of the infrastructure, the bits we can’t see from the ground to really understand if there are any problems with the top of the network.”