Click here to go to the Trees are Good Website - The International Society of Arboriculture

Why is it so important to keep trees near power lines trimmed? Here's the answer...
(see some of your questions answered at the bottom of this page)

"The Annual Talk About Trees and Wires..."
You dread it. We dread it. The trees dread it. Everyone hates it, but the laws of physics demand it. Yes, it is time to talk about tree trimming again.

In the world of operating the networks that provide you with the services and technology you rely upon, there is no issue which is more likely to upset and anger our customers than our tree trimming activities. On the other hand, there is also no matter which is more likely to cause your services to be interrupted than the lack of sufficient tree trimming. This situation provides the quintessential definition of the often used phrase: We are darned if we do and darned if we don't. That is not an exact quote but it is quite close. The only way for us to deal with increasingly violent weather, and increasing demands for reliability of the services we provide, is for us to trim trees in such a manner that they do not provide our electric power a path to ground and do not threaten to damage our broadband network.

We get many, many questions, comments, and suggestions about where we should spend eternity from some of our customers when the tree trimming crews actually arrive in their yard. So, it seems like a good thing to review all of this again.

Our customers tell us time and time again that they hate outages! For more complete information on tree trimming, where we will start and why it's so important (especially to keep outages to a minimum), we've made a short TV presentation that we're showing on Cable 6. You can even watch it here...



A limb in contact with high voltage!
The Problem. It is simple really. Trees conduct electricity and they are connected to the ground. Electric power wants nothing more than to go to ground though any available path (normally we try to force it though lights or motors as it goes to ground such that we get value out of it, but it really only wants to get to ground). The electric wires running along poles are bare and isolated from paths to ground at each pole by insulators. So when a tree branch touches a wire, electricity gets to do what it wants . . . it flows through the tree to ground. When this happens, one of our fuses or circuit breakers trips to interrupt the faulty flow to ground and that is when your power goes off. That is when you call us. Even if the tree is not contacting the conductors sufficiently to cause a power outage, some energy still goes to ground through a tree that is making only intermittent contact. At today's cost of electric power, no one wants to pay extra for the power lost due to intermittent contact with trees. This is all the more reason for us to be very aggressive with our tree trimming.

The Solution. First, before you even think it, let's talk about everyone's favorite solution . . . putting it all underground. That is not a bad idea, if money and time were no big concerns. Borrowing the money to make a real impact on converting overhead lines to underground lines would likely require your electric bills to double (best guess estimate) and it would take many years to accomplish (it has taken the EPB 50+ years to build what we have today so placing it all underground would not happen quickly). The really ugly reality is that the spiraling costs of coal, natural gas, and diesel fuel are likely going to cause dramatic increases in everyone's electric bills anyway, so there is an ever decreasing interest in additional rate increases which would be necessary to provide the capital for undergrounding. Even if the people of Glasgow were willing to accept another 100% increase in their power bills, we would still have to trim trees for dozens of years as this "undergrounding" was taking place.

Therefore, let's talk about reality. The only economically viable solution is for us to trim trees in such a manner that they do not provide our electric power a path to ground. There is a right way and a wrong way to do this as well. For many years, we did it the wrong way. In an attempt to have a minimal impact on the trees and the owners of those trees, we used to randomly cut branches such that after the visit no branch was closer than 3-4 feet from a wire. This sort of "rounding over," "topping," or "shrubbery style" trimming resulted in nicer looking trees, but it also resulted in fewer healthy trees. Cutting a tree branch in the middle of its length, results in dozens of weak new branches being output by the tree at those cuts. Those multiple cuts cause weakness of the new branches and multiple avenues for disease and insects to enter the tree.

Now that we know better. Utility companies and professional arborists now agree. The best way to trim trees, for the tree's health, and for maintaining reliable electric networks, is to use a method called "directional" or "lateral" trimming. Directional trimming strives to train the tree to grow away from and around the wires. These trimming principles were developed by the U.S. Forest Service and are endorsed by the International Society of Arboriculture (a world recognized group of experts in tree health which the EPB is now a member of) as well as tree care professionals across the country. This method is best described as trimming the limbs that are growing in the direction of neighboring electric wires all the way back to their "parent" limb. This method satisfies the clearance requirements for the EPB as well as the health needs of the tree. The figures below are very good representations of the results we expect from employing the new directional trimming method.
As you can see, this method leaves virtually no limb stumps which can issue new sprouts in the direction of our lines. This is the method of trimming that we will employ in all of our new line clearing projects. The matter is not open for conversation or exceptions at any point on our system. While we want to give our customers plenty of notice so that they will not be surprised by the equipment and workers in their yards, we will not be asking permission to do this work. It is required for the people of Glasgow to have utility services that they expect and demand. If you have trees in your yard that are in danger of contacting overhead electric lines, they will be trimmed in this manner.

Billy Ray, Superintendent
(270) 659-3507 - voice
wray@glasgow-ky.com
read my blog at http://rbg.glasgow-ky.com
follow me on twitter at http://twitter.com/wjray_epb
follow the EPB on twitter at http://twitter.com/GlasgowEPB
Feel free to use any of these means to contact me with any questions or comments!


Here's the text of a letter that we have used in the past to notify customers about upcoming tree trimming. After you read through this, take a look at the first question below.

 

 


July __, 2008

Bobby and Belinda Homeowner
123 Shady Lane
Glasgow, KY 42141

RE: Upcoming line clearing work on your street

Dear Mr. and Mrs. Homeowner:

This letter is written to notify you of tree trimming work which will soon be occurring along your street and within our easements on your property. The last time we had contractors in to do electric line clearance work in your neighborhood was in 2005 and recent power outages, caused by trees, point to the need to revisit the neighborhood to do additional work on trees.

Crews from the Glasgow EPB will be arriving sometime between now and the end of the year to perform this work. This is not work which we are happy about doing. It is expensive and it results in ugly, misshapen trees. The prices we are paying to have this work done in 2008, with diesel fuel approaching $5 per gallon, leaves our budget similarly damaged. But, this is the only way to provide low cost and reliable electric power and telecommunications services to our customers. It is an undeniable law of nature that trees conduct electricity and cause outages.

To remedy this problem we will be trimming the trees according to the guidelines stipulated by the International Society of Arboriculture. You can read more about ISA and its recommended tree trimming guidelines, as well as more about our own line clearing practices on the web at http://www.glasgow-ky.com/treetrimming/.Trees will be trimmed using the "lateral trimming" guidelines. All limbs capable of outputting new growth toward the electric lines will be removed. They will not be topped or rounded over or trimmed like a shrub. They will be surgically altered such that we are unlikely to ever need to trim them again. Trees along roadways, such that they are readily accessible by our trucks, shall be trimmed aggressively. Trees in back yards where our access is frustrated by fences, vehicles, swing sets, flower/vegetable gardens, and various outbuildings will be trimmed very aggressively.

Thank you for you attention and understanding of this matter.

Respectfully,

 

William J. Ray, P.E.
Superintendent

 

Here are answers to some of your questions. We'll be adding more to this as you ask more questions...
Will you be sending me a letter when you'll be trimming in my neighborhood?
Probably not this time. Sending letters for this type of thing has become prohibitively expensive, both for postage and the time spent doing it (which might be spent better in other ways). We will be posting the areas where we'll be doing tree trimming work on the Glasgow Website, on EPB Cable 6 and sending out messages via twitter.
I don't see any of my trees that are near your high voltage lines, but I got your letter in the mail (as shown above). Does that mean that you will definitely be trimming one or more of my trees?
No, not necessarily. We sent that letter to all property owners in the areas we're going to trim fairly soon. In other words, letters went to all addresses in that area. However, we're only trimming the transmission and distribution lines (that's the lines that transport the power and the lines that serve multiple customers - the lines going up and down the street). On most streets, those lines are only on one side of the street, not both. Generally, we would only be trimming on the side of the street with the lines.
Trees have been trimmed in my yard. Do I have to clean up the brush?
When we are doing preventive maintenance, such as this, we will clean up the brush. In most cases, it will be cleaned up the same day it's trimmed. In the event of an outage, if your trees cause us trouble, you would dispose of the brush yourself. We have to make the best use of our time in those situations - getting the most people back on in the shortest time!
I'm thinking about just asking you to cut down a tree that's growing into the lines on the street. Will you do that? When do I need to ask?
If one or more of your trees is growing into a high voltage line, we may possibly cut it down at your request. Call us at (270) 651-8341 and choose "5" for the Engineering Dept. They will get one of our personnel to come by and take a look, then we'll get back in touch with you. All we ask is that you make your request BEFORE our tree crews show up to trim at your house. It costs us substantially more to come back after we have already been there.
I have some trees growing into the line that serves my house with electricity. Will you be trimming those?
As the first question above states, we are only trimming the transmission and distribution lines. These are the lines that run all over town. The line that travels from the pole to your house is a "service line" and we do not trim those. However, if you would like to get someone to trim it, we will send one of our service personnel over at no charge to you and remove the electric wiring running to your house. This will allow your contractor to trim with greater safety. After their work is completed, contact us and we will reconnect your power.
I really don't want you to trim my trees, even though they are growing into the high voltage lines. I don't think this is fair.
If what we trimmed only affected your property, you'd be right - it wouldn't be "fair." However, if we don't trim the potentially outage-causing trees on your property, you could affect many other people in the event they cause an outage. What's not fair is to allow one small problem to affect many, many customers - especially if it's something that could have been avoided altogether. Nobody likes outages!

Check out Glasgow's Website at www.glasgow-ky.com!
Click here to check out tree care information on the "Trees are Good" Website - Intl. Society of Arboriculture