Private power poles and overhead lines on your property

On most suburban blocks, supply runs from the street to a point on the house: an overhead service line to a bracket on the fascia or a mast, or an underground cable to a pit and then the meter box. Everything from the street to that connection is network equipment.

Some properties have more. A house set well back on a large block, a long driveway, a rear dwelling, or a shed or workshop some distance away can mean the network connection is at the boundary or the first building, with a private pole or two carrying overhead wires the rest of the way. Energy Safe Victoria calls these private aerial lines: low-voltage poles and wires, usually on private property, that form part of the property's electrical installation and carry supply from the network.

They're more common on larger and older blocks and on rural-residential land, and they're easy to overlook because they look just like network poles.

Energy Safe Victoria uses the point of supply to divide responsibility. Up to that point, the network belongs to the distribution company. From the point of supply in, the property owner is responsible for maintaining and repairing the electrical installation, including private electric lines on the property.

Powercor gives some examples of the customer's side, listing an insecure or missing service hook, a defective fused mains box and a defective meter box as customer installation defects that the customer has to fix. The same line applies to private poles and spans: on your side of the point of supply, their upkeep is yours.

If you're not sure where your point of supply sits, ask your distributor or have a licensed electrician check. It's worth knowing before you buy a property with a pole down the driveway.

Trees cause more trouble on private lines than anything else. Branches rub through insulation, bring lines down in wind and, in hot, dry weather, can start fires. Energy Safe Victoria says owners of private aerial lines are responsible for keeping trees on their property clear of their own service or private lines, and of a private line on a neighbouring property.

Pruning near a live line is not a ladder-and-chainsaw job. Use an arborist trained and qualified to work near powerlines, and talk to your electrician about isolating the line while the work is done.

Plan for regrowth. A tree cut back once will be back near the line within a season or two, so check clearance each spring and after storms. If a branch is touching or hanging on a line, keep clear and get help rather than trying to free it.

Timber poles rot at ground level, where the soil stays damp, and can look sound above while being soft at the base. Poles lean as ground shifts or after a vehicle clips them. Cross-arms, insulators and brackets crack and loosen, and the stay wires that hold a pole against the pull of the line can slacken or be hit.

Lines sag as they age, and a sagging span swings closer to trees, roofs and vehicles. Connections at each end corrode, faster near the bay. For a rotting, damaged or leaning network pole, Energy Safe Victoria says to contact your local electricity distribution company. For a private one, call a licensed electrician and keep people and vehicles clear until it's been looked at.

A private line inspection is a walk along the whole route, from the point of supply to every building it feeds. Regular checks catch problems while they're still repairs rather than failures.

The result should be a written list of what was found, what needs fixing now and what to watch. Keep it with your property records, and use it to plan tree work, pole replacement or a move underground.

Treat any fallen line as live, even when it's broken, and keep everyone well clear of it and anything it's touching, including fences, vehicles and wet ground. If there is smoke, fire or immediate danger, get everyone away from the area.

Contact your electricity distributor, whose faults number is on your bill, so the supply can be made safe. The repair on your side is the owner's to arrange. Energy Safe Victoria says the distribution company will only reconnect power to a private aerial line once a licensed electrician or REC has issued a Certificate of Electrical Safety, so that paperwork is part of getting the power back.

Replacing a private overhead line with an underground cable removes the poles, the tree conflict and much of the storm risk in one go. It makes most sense when a pole or span is due for replacement anyway, when trees along the route can't be kept clear without losing them, when a driveway or building work is going in along the route, or when trucks and machinery pass under the line.

It's a bigger job than replacing like for like: a trench along the route, conduit and cable sized for the load and distance, and work at both ends. Energy Safe Victoria lists consumer mains cables and the main switchboard among prescribed work, which a Licensed Electrical Inspector inspects before the power goes back on. Before any digging, check for other buried services along the route.

If you're building, adding a second dwelling or subdividing, raise the supply early, so the trench, cable size and timing are planned with the rest of the work.