Trees and power lines don't mix

Trees and vegetation can interfere with our network and even interrupt electricity supply.  That’s why it’s important to manage them so that they don’t get too close to power lines.

Network Tasman takes a proactive approach to keeping trees away from our power lines by surveying all of our lines on a regular basis. We store the information collected in these surveys in a database. Our database records the full history of each surveyed site, including the condition of nearby trees.

If we identify trees that are growing too close to power lines, we let property owners know by sending them what is known as a cut and trim notice (CT Notice), as required by The Electricity (Hazard from Trees) Regulations. We issue more than 1500 CT Notices each year. Property owners are responsible for keeping their trees away from power lines.

However, the regulations state that each tree is entitled to one free trim – we record whether a tree has had its free trim in our database.

When our vegetation team undertakes a survey they also look for trees with high-risk issues that could cause the tree to fall onto the lines, such as trees that are diseased, damaged, or have branches splitting out. All of these factors have the potential to damage the network and cause power outages. To help mitigate this risk, we negotiate a solution with the tree owner (this often involves trimming or felling the tree).

Last year, more than 3500 trees posing a risk to power lines were trimmed or felled by network certified arborists.

Surveying our lines and notifying tree owners in this way has dramatically reduced the number of power outages attributed to line damage caused by trees. With the cooperation of tree owners, our electricity supply has been more resilient and storm response costs have been lowered. This means everyone pays less for their electricity.

If you’re a landowner you may have been contacted by one of our surveyors for permission to access your land and undertake a vegetation survey on your property.

Our surveyors are always happy to answer your questions about clearances required, the safe cutting and disposal of trees, and issues with vegetation close to power lines.

It’s important for all of us to keep an eye on trees and vegetation and make sure that power lines are out of harm’s way.

If you have any questions, please contact our vegetation team on 0800 508 098 or email