Updated zones
The zones in the Electricity (Hazards from Trees) Regulations 2003, were updated late 2024 to increase the minimum clearances between trees and power lines and a new 'clear to the sky' requirement for some trees was introduced.
There are three zones: the (hazard warning) Notice Zone, Cut-back Zone and Growth Limit Zone (GLZ)* with different clearance distances depending on the power line voltage.
*While the Growth Limit Zone has increased by one metre, WEL may opt to apply the previous minimum clearance until 16 October 2026.
If your tree is growing within the Notice Zone or Cut-back Zone (Tree A), you may get a notice saying your tree must be cut or trimmed soon because it's growing too close to power lines.
Should the tree encroach the Growth Limit Zone (Tree B), you will get a notice requiring it to be cut or trimmed.
Stay safe
Property owners are responsible for any trees on their property, so it's important to check trees or hedges regularly and take appropriate action if they do pose a risk.
If you observe vegetation across our network which is too close to power lines, please call us on 0800 800 935.
In the diagram shown on the right:
- These distances are from the power line, not the power pole
- These distances are a minimum and apply in all conditions including high wind
- In most instances the power lines that go to a house or building are low voltage power lines
- Power lines that go down a street may be low or high voltage
- For spans greater than 150 metres additional clearances apply
- Trees protected by district plans are excluded from the 'clear to the sky' requirements
