Trees & power lines

Hazards from Trees 

Electricity Regulations 2003 

At Waipā, we value our partnership with tree owners in the region and understand that complying with regulations and responsibilities can be challenging. That’s why we’re here to provide you with the information you need to keep yourself, your community, and the environment safe.

We’ve summarised the six key points that you, as a tree owner in the Waipā region, need to be aware of to comply with the Electricity (Hazards From Trees) Regulations 2003. If we ever need to issue you a notice regarding one of your trees, we’ll provide full details of your rights and responsibilities.

  • If we become aware of a tree you are responsible for growth within the Notice Zone, we may issue you a Hazard Warning Notice. This notice will remind you that you must keep the tree from growing into the Growth Limit Zone. 
  • If Waipā Networks becomes aware of a tree you are responsible for growing into the Growth Limit Zone, we will issue you a Cut or Trim Notice. 
  • You must trim the tree so it no longer infringes on the Notice Zone. You can apply for Dispensation if you believe you have a good reason for the tree to be allowed to grow closer to the lines than usual. 
  • Waipā Networks will trim a tree free of charge the first time (provided we haven’t already done it before the Regulations took effect). After that, you are responsible for the costs of any future trimming. 
  • You can declare ‘No Interest’ in a tree at any stage. Waipā Networks will meet the costs of future trimming, or we may remove the tree altogether. 
  • When we become aware of a tree threatening our lines to cause a danger to the public or property, we can remove the tree or branch causing the hazard.



You can also view the full Regulations online at www.legislation.govt.nz or order a copy through your local bookstore. If we need to issue you with a Notice regarding one of your trees, well provide you with full details of your rights and responsibilities with the Notice. 

In The Zone 

How far apart should they be? 

The Electricity (Hazards From Trees) Regulations 2003 define two zones: a Growth Limit Zone and a Notice Zone (shown in the diagram above). 

Growth Limit Zone 

In relation to Waipā Networks equipment, this is the area within 1.6 metres in any direction of our 11,000V electrical conductors or 0.5 metres for 400/230V electrical conductors. If any of your tree foliage is within this Zone, it must be trimmed beyond the Notice Zone. 

Notice Zone 

This is the area 1 metre in all directions around the Growth Limit Zone. If we know about trees growing in this zone, we may issue you a Hazard Warning Notice to inform you that the tree must not be allowed to grow into the Growth Limit Zone. 

Service Main 

A Service Main is the line that connects your property to our network. This commonly forms an overhead or underground line from the street pole to your house. 

Waipā Networks does not own this and is not covered by the Regulations. You must keep trees clear of this line, and if you need to carry out a trim, Waipā Networks can temporarily disconnect the power (safety disconnection). 

This service is free, provided it is no longer than 15 minutes during business hours (a charge applies for 11 kv lines in all cases). If you would like more information about safety disconnections, please give us a call. 

Meeting the regulations  

As a tree owner, you may be issued a Trim Notice about a tree on your property. You must meet the regulations souring this notice imminently because failing to meet them could be seen as committing an offence: 

  • Fail, without reasonable excuse, to cause the tree to be cut or trimmed per the Regulations, or 
  • Fail, without reasonable excuse, to advise Waipā Networks of the time and location of the cutting or trimming of the tree. 

The fine for this is $10,000 and $500 each or part day during which the offence has continued. 

A dangerous combination 

Keeping you safe around power! 

  • Trees growing close to power lines and other electrical conductors pose a severe risk to public safety. 
  • They may also cause power cuts or voltage problems for connected consumers. 
  • If a tree encounters a live electrical conductor, the current may travel through the tree and into the ground. 
  • Anyone touching or close to the tree could suffer a severe electric shock. 
  • Those at highest risk are people carrying out tree maintenance or children playing in or around a tree, both of whom can cause branches to move and encounter the lines. 

Tree trimming – the dangers 

Limit Zone (see diagram) must only be trimmed by a Waipā Networks authorised person. 

Before clearing tree foliage near live conductors, ask Waipā Networks for advice.
Growth Limit Zone: Any tree growing in the Growth 

Branch Movement:  

Although the tree foliage may appear safely from the lines, once you begin the work, the tree may move due to pressure placed on branches, random wind gusts, or other external interference. 

Things to remember: Tree branches tend to be elastic, so you should also be wary of any that may flick up as they are trimmed or as other surrounding branches are cleared. 

Wet Weather:  

Branches tend to hang lower when the leaves are wet, so you should expect some movement if it starts to rain or if the leaves are already wet and start to dry. 


The path of debris should also be considered when attempting tree maintenance. 

These and other dangers mean we strongly recommend you refrain from trying the work yourself. 

Waikato Tree Services

Waikato Tree Services have cared for trees in Hamilton and surrounding areas for almost 30 years. Since taking ownership in 2010, Waipā Networks Ltd has grown the company to include three teams of fully qualified and experienced arborists, with a fleet of modern, hi-tech equipment, including an 18.5-metre high cherry-picker. You can contact them for any sized job!

Website Here

Email: trees@waikatotrees.co.nz

Tel: 0508 87 33 22

Fax: 07 871 4958

These photos represent severe weather’s impact on trees and power lines in the Waipā region. Extreme weather conditions highlight the importance of maintaining your trees as it reduces potential damage to power lines.