News & Views

15th June 2017

Private Overhead Power Lines

If your customers have private power lines or a private power pole on their property it is their responsibility to inspect and maintain them.  They also need to keep trees and branches clear of the power lines.  This is to help prevent power interruptions and reduce the possibility of electrocution or fire.

This is not a new requirement.  It has always been the property owner’s responsibility to maintain all electrical equipment they own.

Inspections of private overhead power lines and poles

It is important that your customers inspect their private power lines and poles (including stay-wires, fittings and all other components) at least once a year to check for any visible signs of deterioration.  They should never climb a pole, approach wires, attempt any electrical repairs themselves or cut any vegetation near an energised power line.  Contact with live wires can kill!

It is recommended that you advise your customers to:

  • Safely remove any vegetation on the ground close to the base of all power poles and under the power lines;
  • Check that trees and branches are at least two metres away from power lines.  If they are not, arrange for tree pruning by a competent vegetation control contractor.  Check the Yellow pages:
  • Check wood poles for obvious defects such as poles which are cracked, damaged, rotting, attacked by white-ants/termites and ask your white-ant/termite inspector to treat (if required) the area around the poles;
  • Inspect steel poles regularly (e.g. every year)  Steel poles, even galvanised, are subject to rust and should be checked above and below ground for defects; and
  • Check all poles for leaning, brackets pulling away from poles/buildings, damaged stay-wires, split cross-arms, broken strands in wires, damaged insulators or wires hanging much lower than others in the same section.

 

If they come across any of these defects during a visual inspection, they should immediately arrange for further inspection or repairs by you as their licensed electrical contractor or another contractor with the relevant skills and competencies.

Life expectancy of wood poles

Australian Standards indicate a life expectancy of up to 40 years above ground and 25 years below ground for hardwood poles.  However, the life expectancy of wood poles can vary significantly depending on their uses, species, climatic conditions and soil conditions.

If your customers’ poles are hardwood, it is recommended that they replace all those that have been in service for more than 25 years.  The difficulty in detecting internal deterioration and rotting in hardwood poles makes age-based replacement the only reliable option.

Alternatively, if their poles are softwood, such as treated pine, it is recommended that they seek information from the manufacturer or your supplier (if known) about the life expectancy.  They should then replace those poles that are older than the indicated serviceable life.

If their poles are made of sawn timber, they should immediately replace them.  Sawn timber is not suitable for power poles as it is more prone to rot and structural deterioration, with a high risk of early failure.

Groundline reinforcement using galvanised steel stakes can also extend the life of wood poles.  Such an option should only be considered if the reinforcement work is performed by a company specialising in such activities.

My customers’ power poles need replacing.  What are their options?

a. Underground

If the private power poles or lines on their property has exceed their serviceable life, it is recommended that they consider replacing them with an underground cable.

The benefits of an underground cable are:

  • It is far safer than an overhead line.  It eliminates the risk of starting a bushfire and the risk of electrocution through contact with farm equipment is minimised:
  • An underground supply is far more reliable, not affected by weather or vegetation; and
  • It does not require maintenance

b. Pole replacement

Should their overhead power lines need substantial repair and they decide to continue with overhead power lines, they should use new steel poles and insulated wires in preference to wood poles and bare overhead wires.