Proactive Wildfire Prevention

An all-terrain tree trimmer is used to keep NLI’s rights-of-way clear of trees, limbs, and brush that could come into contact with power lines. Photo by Kristin Mettke

Wildfire prevention is an ongoing concern among all electric utilities, especially those serving heavily forested regions. Northern Lights Inc. performs proactive fire prevention and takes all precautions to protect lines from the threat of wildfires.

NLI has numerous practices and plans to minimize potential fire impact. Fire mitigation encompasses a combination of vegetation management, operational practices, inspection and maintenance, design and construction, response and recovery, and situational awareness.

Vegetation management is a huge part of fire mitigation for NLI. A large portion of our annual budget is spent on tree trimming and removal. This is for reliability and wildfire prevention.

You likely have seen one of our contract crews out trimming trees around NLI power lines. They use several pieces of equipment, including chain saws, mowers, mulchers, and an all-terrain tree trimmer.

NLI trims 200 to 250 miles of rights-of-way annually. As for tree-related outages, many are caused during the snow season when trees can become loaded with snow or ice and lean or fall into overhead power lines. A strong wind any time of year can also cause major issues with trees.

Most of NLI’s distribution power lines are 30 to 45 feet above ground, and easements are typically 40-feet wide. Many of the softwood species in our area, such as pine, grow more than 100 feet tall. If you do the math, you can see there’s a good chance if a tree falls into NLI’s right-of-way, it will fall on a power line.

When given permission by a landowner, NLI will remove hazardous trees outside our easement that pose a threat to power lines. Hazard trees are dead, leaning or damaged—in other words, trees that need a little bit of extra force to fall over.

If you have a concern about a tree near a power line on your property, please report it using the “Request Tree Clearing” form on our website or call the main office during business hours at (208) 263-5141.

As for fire concerns, a branch could fall on a power line, create an arcing flame and start a fire. This is what we aim to prevent with tree trimming. Another way to minimize the impact of a potential arcing flame is through our system protection devices. If the line can be de-energized quickly by blowing a fuse or opening a recloser, we may be able to reduce the size and duration of an arc.

Our generation and transmission service provider, the Bonneville Power Administration, has its own fire mitigation plan. We rely on BPA to deliver power to NLI.

Under extreme circumstances, BPA could de-energize lines as a safety precaution to prevent a vegetation-related fire. Although we do not believe this will happen, it is a possibility. We will communicate this to our members as best we can, should that happen.

If you see a questionable tree or branch hanging over a power line or something that looks off with one of our poles or lines, please call and let us know so one of our lineworkers can take a look. It may prevent a fire.

Kristin MettkeNorthern Lights Engineering & Operations Manager Kristin Mettke is an electrical engineer and has worked in the electric utility industry most of her career.