Three kinds of power lines

There are three kinds of power lines: transmission lines, distribution lines and service lines. Individuals can’t own or be responsible for transmission lines or distribution lines, even when they are on private land. Transmission lines are owned, for the most part, by Transpower (a State-Owned Enterprise) and distribution lines are owned by electricity distributors like Vector, Powerco and Orion. However, service lines may be your responsibility.

Service lines

It is not always obvious who owns service lines. If you are the only end consumer supplied by a service line and the line is located on your property, it is likely that you own the line. If the line supplies other consumers too, you might own the line jointly with them. In some situations, a service line or a portion of a service line may be owned by the electricity distributor, most often where the line serves a number of consumers.

The history of the service line makes a difference

The position is relatively straightforward for lines built from the start of 1993, when the Electricity Act 1992 came into force. From that date, line owners need easements or other contractual arrangements with land owners to build and access power lines on private land. But the question of who owns lines built before that date is more complicated. Ownership cannot be determined based only on who paid for a line to be built. It also depends on when the line was built, the legislation in place at that time, any contractual arrangements that may have altered this position and whether the line crosses, or supplies electricity to, other people’s properties.

Ask your electricity distributor for advice

It can also be difficult to tell where the distribution line ends and the service line starts. This demarcation point is not always at the property boundary but could be inside or outside that boundary.

If you are unsure about who owns and is responsible for maintaining a service line and where it starts and stops, the electricity distributor in your area should be able to tell you. When buying a property, especially a rural one, it is worth checking what power lines cross the property, who owns them and who is responsible for maintaining them. You should also check if there are any easements in respect of those lines.

Why does line ownership matter?


One of the main concerns you, as a property owner, will have with owning the service line is that you might be responsible for maintenance. As owner of the line, you are responsible for maintaining it – unless you have agreed otherwise with a third party. At least one electricity distributor has taken the approach that it will maintain customer service lines, but most do not.

In most urban environments this is not a big responsibility. However, some farms have service lines that are several kilometres long. If the lines come down, it is your responsibility, as the owner, to repair them. You may also be liable for damage caused by the line to your and other people’s property.

Access to land

Even though you do not own the distribution or transmission lines on your property, you still have rights and responsibilities in relation to those lines. As mentioned above, for newer lines, the line owner will have needed to have an easement or other contractual arrangement with you to build the line. Under the easement or contract, the line owner will have the right to access your property to maintain the lines.

For older lines where there is no agreement in place, line owners have the right under the Electricity Act to access your land to inspect, maintain and replace the lines (so long as the replacement does not injuriously affect your property). You can also set reasonable conditions on the line owner’s access, but those conditions cannot include payment of money and they cannot delay the work more than 15 working days.

The line owner must give you notice in advance of an intention to enter your land to access its works, except in the case of emergencies, where notice can be given after the entry.

Moving power lines

What if you want to build on your land, but a power line is too close to the best building site, or obstructs the view? The Electricity Act allows you, at your expense and with the consent of the line owner, to arrange for the lines (including, obviously, the poles) to be moved.

Trees and power lines

The Electricity (Hazards from Trees) Regulations 2003 govern the control of trees around power lines. As a property owner, your obligations under the regulations will be reinforced by your contract with an electricity retailer. That contract will require you to keep trees and other vegetation away from power lines and other electrical equipment on your property.

This requirement is reflected in your retail contracts because, as a consumer, you are unlikely to have a direct contractual relationship with an electricity distributor. Consumers contract with electricity retailers, who, in turn, contract with distributors and generators.

How close is too close?

The Regulations set ‘Growth Limit Zones’ around power lines. Trees must not encroach upon these zones. The size of the zones vary depending on the voltage of the lines – for an 11kV line, trees must not be permitted to grow within 1.6m of power lines in any direction. The zone for high voltage power lines (66kV and higher) is four metres. Additional limits apply for line spans of 150 metres or more to manage the risk of lines swinging in high winds.

Who is responsible for keeping the trees outside the zones?

As the land owner, you are responsible for keeping trees away from the service lines on your property. The zone around the standard residential 230V service line is 0.5 metres.

You are also primarily responsible for keeping your trees away from distribution and transmission lines on and around your property. If an electricity distributor becomes aware of trees encroaching the zones around their lines, they will send you a Cut or Trim Notice requiring the trees to be cut or trimmed. [link to cut or trim notices]

If the line owner has never trimmed the trees before, and the trees do not form part of a shelter belt, the line owner will generally pay for that – the first – trim. But after that, you are responsible for keeping your trees away from the power lines so you will have to pay for subsequent trims.

When you plant trees, you should always consider what power lines are around. That way, you can make sure that you plant the right kind of tree in the right place so the trees do not interfere with the lines.

What if the tree damages the lines?

If your trees damages power lines (even if the trees are not in the zones discussed above), you may be liable to the electricity distributor for the repair costs, as well as for other costs associated with resulting power outages.

Who can cut trees near power lines?

The Maintenance of Trees Around Power Lines Code of Practice – an approved code of practice under the Health and Safety in Employment Act 1992 – specifies best practice for working on trees near power lines. The code provides that only people who are competent under the code should work in close proximity to live power lines. The New Zealand Electrical Code of Practice for Electrical Safe Distances (ECP 34) provides minimum approach distances to live lines, which may be reduced for competent workers with the approval of the line owner.

As a property owner, due to the risks of contact with the line, you should always use trained line-clearing experts to clear trees around lines. Your electricity retailer will be able to advise you which contractors are able to do this work.


If, after receiving a Cut or Trim Notice, you fail to have your trees cut or trimmed, or you fail to give the electricity distributor at least 3 working days’ notice of when the work will be done, you can be fined up to $10,000.

Electricity distributors can also be fined for breaching their obligations under the Regulations.

Distributed generation

More and more people are generating their own electricity, with solar systems, wind turbines, small-scale hydro schemes and other mechanisms. If you produce more power than you need, you can connect to the electricity network and sell the excess electricity. This is called distributed generation.

If you want to do this, you must ensure that:

  • your generation equipment complies with all laws and standards, such as the relevant Electrical Codes of Practice and electricity distributor’s policies;
  • you have appropriate meters for measuring the amount of electricity you supply;
  • an electricity retailer has agreed to purchase the electricity; and
  • an electricity distributor has agreed to connect your generator to their distribution network. This can be either on terms you agree with them or under the regulated terms set out in the Electricity Governance (Connection of Distributed Generation) Regulations 2007.

Electricity distributors need to know where all distributed generators are connected to their networks, and they need to be able to isolate them when necessary. For example, if work is being done on part of the distribution network, it is important that a distributed generator is not inadvertently injecting electricity into that part of the network. Electricity distributors must also ensure that distributed generators do not interfere with the smooth and safe operation of the networks.

If you want to put your surplus electricity back into the network, talk, in the first instance, to your electricity retailer or local electricity distributor.