TREES & VEGETATION
Trees & Vegetation
Trees and branches near power lines can pose serious risks to the public and can cause power outages, especially during high winds and storms. This page tells you what you need to know and do about your trees.
Trees that grow too close to power lines can be a serious problem. They can cause electric shock, fire, power outages and damage electricity infrastructure.
Keeping vegetation safely clear of power lines helps protect people and helps keep the lights on for you and your community.
The Electricity (Hazards from Trees) Regulations set out the rules that tree owners and lines companies must follow when managing trees near power lines. These regulations are part of New Zealand law.
This page explains the main rules, including what tree owners need to know. If you’re unsure about a tree near a power line, please call us on 03 577 7007 or report a fault here before doing any work.
If there is immediate danger
Call 111 immediately if there is an emergency.
Never touch a power line, and never touch a tree or branch that is touching a power line. If you come across downed lines, never approach or attempt to clear them yourself. Stay at least 10 metres away and call 111.
You should also contact us immediately if:
a tree or branch has fallen onto a power line
a tree looks like it could fall onto a power line soon
a power line is down, damaged, or hanging low
branches are touching lines
someone is at risk of coming into contact with the line.
Who is responsible for a tree near a power line?
In most cases, the tree owner is responsible for making sure their tree doesn’t grow too close to power lines. A tree owner is usually the person who owns the land where the tree is growing.
We have responsibilities too. These include:
carrying out line and vegetation surveys
providing information about the rules
issuing hazard warning notices and cut or trim notices where the regulations allow or require
responding to electricity hazards
in some cases, meeting the cost of certain work required under the regulations.
How the rules apply
The regulations use several zones around power lines. These zones help determine when trees must be trimmed, when notices can be issued, and what restrictions apply.
Trees growing too close to a power line
The regulations include three zones around a power line. These help explain when vegetation is getting too close and when it needs to be cut back.
Growth limit zone: The space immediately around a power line that must be kept clear of vegetation. The size and shape of the growth limit zone depends on the voltage of the line and, in some cases, the span length of the line.
Cut-back zone: This extends 1 metre out from the growth limit zone. If a tree is growing into the growth limit zone, it needs to be trimmed back far enough to reach the cut-back zone unless a dispensation applies.
Hazard warning notice zone: This extends 2 metres out from the growth limit zone. If vegetation enters this zone, we may issue a hazard warning notice to alert the tree owner.
If a tree qualifies for its first cut or trim under the regulations, Marlborough Lines will pay for that work. After that, keeping the tree clear of the power line - and paying for any trimming that’s needed - is the tree owner’s responsibility.
Different rules can apply in some circumstances, so check with us if you’re unsure.
Trees that could fall into a power line
The treefall hazard zone is an area that extends 24 metres from the growth limit zone.
Trees within this zone may be assessed by a lines company. This does not mean every tree in the zone is a hazard. It means the tree may be assessed if there is concern that, because of its condition, size or location, it could fall onto the power line. A formal treefall hazard notice can only be issued if the tree is assessed as a moderate or high hazard.
Treefall hazard notices will not be issued before 23 July 2028. Before then, Marlborough Lines may use voluntary processes to discuss hazardous trees with tree owners. These voluntary processes are separate from the formal treefall hazard notice power in the regulations.
Planting a new tree near a power line
On 23 July 2027, a low height planting rule comes into effect. This means you must not plant a tree if you reasonably expect it could grow taller than its distance from the power line.
The low height planting zone extends 24 metres horizontally from the power line.
If you plant a tree in breach of this rule:
you may be liable for damages
you may be responsible for the cost if the tree later needs to be cut, trimmed or removed
you cannot use a ‘no-interest’ tree notice to transfer responsibility for managing the tree to Marlborough Lines.
The planting restriction does not apply to trees that grow naturally. However, if a self-sown tree within the low height planting zone later needs to be cut, trimmed or removed, the tree owner may be responsible for the cost.
There are some exceptions. The low height planting zone does not apply:
on existing forest land
in urban areas
to shelterbelts
on land administered under the Conservation Act 1987.
Not sure whether your property is in an urban area? Check your district plan or contact Marlborough District Council.
Vegetation growing above the line - ‘clear to the sky’
For some power lines, the growth limit zone extends vertically above the line as well as around it. This is known as ‘clear to the sky’ and means vegetation must also be kept clear above the line.
Clear to the sky already applies to higher-voltage lines in both urban and non-urban areas. From 17 October 2026, it will also apply to lines at 11 kV or below outside urban areas.
What happens if a tree grows too close to a line?
If a tree is too close to a power line, we may contact the tree owner. Depending on the situation, this may include:
providing information or advice
issuing a hazard warning notice
requiring the tree to be cut back
taking further action allowed under the regulations if the issue is not addressed.
The exact process depends on the type of risk and which rules apply. If you receive a notice, it's important to read it carefully and act within the required timeframe.
Tree notices and what they mean
| Notice / process | When it may be used | What it means | What the tree owner may need to do | Who pays? |
|---|---|---|---|---|
| Hazard warning notice | Vegetation has entered the hazard warning notice zone. | This is a warning that the tree is getting too close. | Monitor the situation and act before the tree reaches the growth limit zone. | n/a |
| Cut or trim notice | Vegetation has entered the growth limit zone. | The tree must be cut back as required by the notice. | Arrange for the tree to be cut safely and notify the lines company as required. | If the tree qualifies for its first cut or trim under the regulations, the lines company will pay for that work. After that, ongoing trimming is generally the tree owner’s responsibility. See section below titled ‘offences and penalties.’ |
| Treefall hazard notice (from 23 July 2028) Before this date, discussions with tree owners about hazardous trees will be voluntary | After written advice from a qualified and experienced arborist about the likelihood of the tree falling, a tree in the treefall hazard area has been assessed as a moderate or high hazard. | The tree must be removed within the timeframe set by the regulations. | Work with the lines company on safe removal as per the notice. A moderate hazard tree must be removed within 45 working days. A high hazard tree must be removed within 25 working days. | In most cases, the lines company meets the reasonable cost of removing the tree and associated debris. However, there are exceptions. For example, if a tree was planted unlawfully in the low height planting zone, the tree owner may be responsible for the cost. |
| No-interest tree notice | In certain situations, an owner or occupier may say they have no interest in the tree. If you have already received a cut or trim notice or, from 23 July 2028, a treefall hazard notice, the no-interest notice must generally be given within 10 working days. | This may affect who carries out the work and who manages the tree next. | Follow the process and timeframes in the regulations and any local guidance. | n/a |
What if I disagree with a notice or assessment?
Different review or dispute options may be available depending on the type of notice or issue.
For some matters under the regulations, disputes may be referred to the Tree Arbitrator. The WorkSafe website lists the current Tree Arbitrator and further information. Some issues may also be raised with Utilities Disputes, depending on the complaint.
If you disagree with a notice you receive, contact Marlborough Lines as soon as possible so the next steps can be explained.
Vegetation Control Programme
MLL operates an ongoing and extensive vegetation control programme to reduce the risk of:
accidental electric shock or electrocution.
fires caused by electricity.
power fluctuations or interruptions caused by branches touching, or being blown into power lines.
For vegetation control work we endeavour to come up with a solution that is mutually acceptable to both the tree owner and MLL. We need to eliminate the problem for a reasonable period of time given we have over 3,300km of line which needs to be kept free of vegetation interference to help us provide a reliable power supply to the community.
MLL has an ongoing vegetation control programme in place to help maintain a safe clearance between trees and power lines where they are situated in a public location.
Service Lines
The property owner is responsible for the maintenance and repair of electrical lines and equipment, known as services lines, on their property. This means property owners are responsible for the costs of trimming trees near their service lines.
You can hire a qualified arborist, or you can do-it-yourself - but remember that unless you are using someone qualified to work around live lines, always have your power supply temporarily disconnected before working near service lines.
For a list of authorised contractors click here.
To arrange a temporary safety disconnection complete the form below.
How You Can Help
If you know of trees that are causing interference with a power line (or have the potential to), please call us on 03 577 7007 or report a fault here.
Keep our power lines free of vegetation interference by only planting recommended trees under or near our power lines. These are trees that grow less than four metres tall and don’t tend to shed branches or fronds.
Comply with any notice to cut or trim a tree - it’s in the best interests of all parties, including the tree.
If you have any non-urgent tree and vegetation related questions please click on the button below and our vegetation team will contact you. We also have a list of helpful frequently asked questions which can be viewed here.
Electricity (Hazards from Trees) Regulations 2003
These Regulations were introduced by the government because trees need to be kept at a safe distance from electricity lines for public safety and to protect electricity supply.
The regulations:
define safe separation distances between trees and power lines.
specify who is responsible for ensuring clearances are maintained.
place potential liability on the tree owner if any damage or accident occurs when trees touch power lines.
If your tree is growing within the Cut-back zone or Notice Zone (Tree A), you may get a legal notice saying your trees must be trimmed soon because they’re getting too close to power equipment. This is called a Hazard Warning Notice.
Should they reach the Growth limit Zone, (Tree B), you will get a legal notice requiring them to be trimmed. This is called a Cut or Trim Notice.
Our website has a list of authorised contractors.
For further information on minimum safe distances for excavation and construction near poles or stay wires, you should refer to Worksafe NZ’s ECP 34 - New Zealand Electrical Code of Practice for Electrical Safe Distances (NZECP 34:2001).
Safe Separation Distances
The Regulations specifically advise rules for tree owners and electricity network companies with regard to cutting or trimming trees that grow too close to power lines.
Distances are for spaces surrounding the electrical conductors for spans less than 150m, and LV and 11kV lines.
| Line Voltage | Growth Limit Zone (Qualified Utility Arborists) | Cut Back Zone (*Any Tree Worker) | Notice Zone (*Any Tree Worker) |
|---|---|---|---|
| 11,000 (11kV) | 1.6m | 2.6m | 3.6m |
| 400V/230V (LV) | 0.5m | 1.5m | 2.5m |
*ECP34 must also be adhered to, a person or machinery cannot be within 4m of the line unless a Close Approach Permit has been applied for.
Distances are from any point from the line, except for vertically upwards, which should remain clear (clear to the sky).
| Line Voltage | Growth Limit Zone (Qualified Utility Arborists) | Cut Back Zone (*Any Tree Worker) | Notice Zone (*Any Tree Worker) |
|---|---|---|---|
| 33,000v (33kV) | 2.5m | 3.5m | 4.5m |
*ECP34 must also be adhered to, a person or machinery cannot be within 4m of the line unless a Close Approach Permit has been applied for.
Long Line spans, greater than 150m, distances surrounding the conductor except for vertically upwards, which should remain clear (clear to the sky).
| Length of Span | Distance From Below The Line | Horizontal Distance 15% of each span at either end of the span | Horizontal Distance of the distance for the centre 70% of each span |
|---|---|---|---|
| 150m to 300m | 4m | 4m | 8m |
| 301m to 500m | 4m | 7.5m | 15m |
| 501m to 700m | 4m | 15m | 30m |
| Greater than 701m | 4m | 25m | 50m |
Penalties
Electricity networks and tree owners must comply with the requirements of the Regulations and are both liable for financial penalties if they fail to comply.
A notice to cut or trim a tree cannot be ignored.
Tree owners must comply with the notice in the time stated and advise of the time and location of the cutting or trimming of the tree, or they could be fined up to $10,000 plus other costs, and could also be liable for costs if power lines and/or equipment are damaged by a tree. If the offence continues, a further fine of up to $500 per day could be imposed for every day, or part of a day, that the offence continues.