Growth Limit and Notice Zones

The Electricity (Hazards From Trees) Regulations 2003 state exactly how close trees may come to power lines before cutting or trimming is required. These measurements, or Zones, are known as the Growth Limit Zone and the Notice Zone.

The Growth Limit Zone is the space around the power line where trees must not encroach even in windy or stormy conditions.  The Notice Zone is one metre beyond the Growth Limit Zone (refer to diagram).

Refer to the table below for minimum allowable distances between trees and conductors of different voltages.

Overhead Line

Notice Zone

Growth Limit Zone

33kV - High Voltage

3.5 metres

2.5 metres

11kV - High Voltage

2.6 metres

1.6 metres

400V/230V - High Voltage

1.5 metres

½ metre

Note:

  1. The above distances are from power lines.
  2. Distances must be maintained under all conditions, e.g. high wind.
  3. Low voltage is the power line between the house/building and Horizon Energy’s transformer.

A Cut or Trim Notice

If Horizon Energy becomes aware of a tree encroaching into the Growth Limit Zone, it will give notice in writing to the tree owner that the tree must be cut or trimmed. This notice is the Cut or Trim Notice.

A First Cut or Trim Notice

The First Cut or Trim Notice, issued by Horizon Energy to the tree owner, differs from all subsequent notices because Horizon Energy meets the cost of the first cut or trim of the tree (provided no prior agreement is in place and provided the tree owner grants access to the site).  Subsequent tree clearance work will be the tree owner’s responsibility.

Regulations Provide for Heavy Fines

A tree owner who has been given a Cut or Trim Notice and fails to cut or trim the tree so that it does not encroach the Notice Zone, or fails to advise Horizon Energy of the time and location of cutting or trimming of the tree, may be liable on summary conviction to a fine not exceeding $10,000, and if the offence is a continuing one, a further fine not exceeding $500 for every day which the offence continues.

No proceedings may be taken if the tree owner has applied for a dispensation from Horizon Energy or where a dispute with respect to the tree concerned has been referred to an arbitrator.

If you have any queries about trees and vegetation please read our Trees FAQs, or

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