Safety and trees
Did you know that vegetation causes around 20% of our unplanned outages?
Vegetation, such as trees, hedges, vines and plants touching the power lines are also a safety risk to you and our community. That's why keeping vegetation clear of power lines is an important job we tackle together.
We manage trees and vegetation on our network in accordance with the Electricity (Hazards from Trees) Regulations 2003, which outline the responsibility of both the electricity distributor (Unison) and tree owner (you) in managing trees near power lines.
In October 2024, the regulations were updated to increase the minimum safe distances between vegetation and power lines, and a new ‘clear to the sky’ requirement for some trees. Learn more about the updates here.
Keep Trees Clear of Power Lines
Managing vegetation near power lines is an important part of being a property owner. Take some time to learn more about the danger and risks of vegetation near power lines, and what your responsibilities are as an owner.
How you can help:
- Plant wisely: Avoid planting near power lines if possible. If planting is necessary, choose the right species. Unison provides guidance at www.unison.co.nz/planting-guide.
- Check your property: Regularly look for overgrown vegetation and ensure it is kept at least four metres clear of power lines.
- Call in the experts: If trimming or cutting is needed for your property, contact your local arborist. They’ll liaise with Unison before starting work to ensure it’s done safely.
- Report problem trees: Spot trees or vegetation touching power lines elsewhere? contact Unison at 0800 2 UNISON (0800 2 86476) or visit www.unison.co.nz/problem-tree to report the issue.
- Know your responsibilities: Property owners must keep trees clear of power lines and underground power cables. Failure to maintain them could result in damage costs or fines. Learn more at www.unison.co.nz/tree-notices.
Trees near our network lines
We monitor trees growing close to our network lines and will send you a First Cut or Trim Notice, or a Cut or Trim Notice, if your tree is too close.
Keeping trees clear of lines keeps everyone safe. That’s why it’s important trim or cut your trees when we ask you to. If you don’t act on a notice within the given timeframe, you could face a fine of up to $10,000, plus an additional $500 per day until the work is completed. You may also be liable for any costs associated with damage to power lines or equipment caused by your tree. Please work with us to keep our network safe.
Trees near your service line
Property owners are responsible for ensuring that trees do not encroach on private service lines, which are usually low voltage (230 V or 400 V). We will not issue notices for trees encroaching on these lines.
Working near power lines is dangerous and those cutting trees near live lines are at risk of electrocution or serious injury. If you need to trim trees near a service line, you can request a Safety Disconnection from Unison to make sure it's done safely (some conditions may apply). Your local arborist may also be approved to work near power lines, so consider using them for the job.
Need your trees cut or trimmed?
If your trees, hedges, vines or plants are growing close to Unison's network power lines, you must use a professional arborist certified by Unison to cut or trim your trees. Contact your local arborist and they will get in touch with us before working near the lines.
Doing this work yourself is extremely dangerous and puts you at risk of electrocution or serious injury.
Damaging power lines while cutting or trimming can also be costly, with the cost of repairing power lines and other equipment potentially passed on to you. Stay safe - always use a certified arborist.