Information about tree trimming and why it's important
Trees are a vital element of our region's quality of life. But under certain conditions, they can be dangerous. Toppled trees and broken branches are a major cause of power outages for local homes and businesses. In fact, trees cause more than 2,000 PSE outages each year.
We spend $12.5 million annually to prevent outages
That's why our vegetation management program, formed in 1987, uses a comprehensive, thorough and consistent approach to managing vegetation growing near PSE's power lines and electrical facilities. Today, we budget $12.5 million annually to tree trimming and selective removal.
How vegetation management works
As part of the vegetation management program, our certified arborists inspect PSE's power lines, then trained tree crews perform the necessary work. Trees along higher voltage transmission lines are addressed every three years, and lower voltage distribution lines every four to six years. PSE sends written notification to customers in advance of the work.
Crews follow recommended techniques for trimming and removal
Where proper clearance can be achieved through trimming, our crews use natural pruning techniques, also known as directional trimming. Natural pruning concentrates on removing limbs and branches where the tree would normally shed them, and directing future growth out and away from the electrical wires. In select cases where pruning does not prevent a particular threat to PSE's power lines, our arborists choose tree removal as a second option.
Arborists do not recommend topping trees. As a general rule, PSE does not top trees within the easement area. Topped trees will usually re-sprout, and the new sprouts have weak attachments to the main stem. Over time, the new sprouts will become a greater hazard than the original tree. Additionally, if a tree is severely topped it will die.
"Tree Watch" targets danger trees outside our rights-of-way
We typically address trees growing within a 12-foot radius of the lines on PSE's rights-of-way. In order to address trees outside this radius and on private property, we developed a program called Tree Watch. Certified arborists work with communities and property owners to identify "at-risk" trees more than 12 feet away from power lines. With the owner's consent, we remove these potentially dangerous trees at no charge to the customer.
Contact PSE if you see a threatening tree
Don't wait! Call us at 1.888.225.5773 if you know of a potentially dangerous tree. We'll send out a certified arborist to investigate and determine if the tree in question is a safe distance from our electrical facilities.
Download the information
Tree removal requirements for 230 kV lines (2 MB PDF)
NERC 230 fact sheet (145 KB PDF)
Vegetation management brochure (3 MB PDF)
Natural pruning methods (509 KB PDF)
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