Outages and safety

Trees and power lines

Why tree maintenance matters

Trees are an important part of our city. Making sure they don’t contact wires is important to help avoid outages and injuries.

Trees and branches are good conductors, this means that they only need to come close to a wire for electricity to arc, or 'jump' and travel through them and cause a shock or a fire.

Tree Interference on your property

If your trees contact your service line, we recommend you call a trained arborist to trim your trees. To avoid problems from growth, plant new trees away from lines.

Property owners are responsible for trees that interfere with their own service line, which runs from the pole line to the house.

Tree Trimming Program

Our crews survey neighbourhoods on a three-year cycle to identify trees and branches that are too close to the wires that run from pole to pole in public areas such as parks or along roads and back lanes. We do this to keep our crews safe while working on the wires and to help avoid outages.

You will receive a notification

If a tree on or near your property is being trimmed because it is too near powerlines that run from pole to pole.

Who does the trimming

ISA certified arborists are hired to trim and cut trees. They have the experience and training to do this work safely and while maintaining the tree’s health.

It’s a three-year trim

The trimming is done so that at least a minimum clearance of one metre is maintained during three years of growth. Depending on the type of tree and its growth rate this could mean the amount removed could vary.

Tree planting guidelines

Choosing the correct location to plant your tree is a great first step to protecting the wires and electrical equipment around your home, avoiding outages and helping to keep you and your neighbours safe.

The closer trees or shrubs are to electrical poles and wires, the shorter and narrower they need to be. Trees that grow close to or over wires are a significant cause of damage and outages as well as posing a safety risk for you and your neighbours.

Local garden centres and tree farms can provide details on which trees would be a great choice for your yard.

Before you start working

Contact Click before you dig to locate any underground services.

Visit utilitysafety.ca

Planting Distance Guide

If you’re planting a tree in a neighbourhood with overhead wires, use this guide to locate your tree safely.


Clearance zone: No trees or shrubs can be planted within one metre of the widest extension of electrical equipment.

Short zone (min. 1 metre from wires and poles)

Trees and shrubs up to two metres tall (e.g. hedges) can be planted in this zone.

Medium zone (min. 5 metres from wires and poles) 

Trees in this zone can have a maximum mature or pruned height of four metres.

Tall zone (more than 10 metres from wires and poles)

Any height of tree is acceptable in this zone.