The Regulations

The Electricity (Hazards from Trees) Regulations 2003 were introduced by the Ministry of Economic Development (now Ministry of Business, Innovation and Employment) to help ensure both the safety of the public and security of supply. They also outline the obligations of both the tree owner and the electricity lines company.

The purpose of these regulations is to protect the safety of the public and the security of electricity supply by:

  • Prescribing safe distances between power lines and trees (Notice Zone and Growth Limit Zone);
  • Establishing rules for who is responsible for cutting or trimming trees close to power lines;
  • Outlining liability if the rules and Regulations are not complied with; and
  • Providing an arbitration system for disputes between electricity lines companies and tree owners over the operation of the regulations.

Your electricity lines company (Westpower) relies on the common sense of its consumers to “do the right thing” and ensure that trees on their property do not grow within close proximity to any power lines. However, on occasion, Westpower will be left with no alternative but to use the regulations to ensure that safety and security of supply are maintained. The regulations provide Westpower with the ability to issue a range of notices to support these objectives.

You can view the Electricity (Hazards from Trees) Regulations by visiting :

The Notice Zone and Growth Limit Zone

The Electricity (Hazards From Trees) Regulations 2003 state exactly how close trees can come into contact with power lines before cutting or trimming is required. These measurements are known as zones. The Growth Limit Zone is the space around a power line where trees must not encroach. The Notice Zone is the distance measured one metre beyond the Growth Zone. 

The ‘Westpower Consent Zone’ is the area that can only be entered by a Westpower approved person/contractor.  The New Zealand Electrical Code of Practice for Electrical Safe Distances (NZECP 34:2001), states for non-competent persons working near exposed live parts, where written consent from the owner of the live parts has not been obtained, the minimum safe approach distance limits are: 4 metres for circuit voltages 110 kV and below.