37 minutes | Jan 4, 2021

What Happens When Electricity and Trees Mix?

Electricity and trees seldom mix. But that doesn't mean they can't be good neighbors. Across the city of Ottawa, there are an estimated 185,000 trees in proximity to Hydro Ottawa's 2,800 kilometers of overhead high-voltage power lines. The lines run to all neighborhoods bringing electricity to over 340,000 homes and businesses. As a utility, the goal is to balance power supply reliability with environmental concerns, such as respecting the natural beauty of our community’s tree canopy. In this episode, Nick Levac, Supervisor of Distribution Operations at Hydro Ottawa, and Greg Tipman, Forestry Inspector at Hydro Ottawa, share all about their efforts in striking this balance.

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Dan Seguin  00:42

Hey, everyone, welcome back. This is the ThinkEnergy podcast. Dr. Thomas Fuller said it best, "He that plants trees loves others besides himself." And that dates back to 1732. Now let's fast forward to today. Based on aerial imagery and laser sensory technology, the National Capital Commission reported in a recent study that nearly half of the National Capital Region is under the cover of trees: 46% to be precise. Given Dr. Fuller's memorable quote, it looks like Ottawa-Gatineau has a lot of love for its residents. And if you know anything about electricity, you know that electricity and trees seldom mix. But that doesn't mean they can't be good neighbors. Across the city of Ottawa, there are an estimate of 185,000 trees in proximity to Hydro Ottawa's has 2800 kilometers of overhead high-voltage power lines. The lines run to all neighborhoods bringing electricity to over 340,000 homes and businesses. As a utility, the goal is always to balance reliability of the power supply with the environmental concerns such as respecting the natural beauty of your community’s tree canopy. Trees provide all sorts of environmental and energy saving benefits from absorbing CO2 to releasing oxygen back into the air, to providing shade from the sun and reducing excess heat in our home if they're planted in the right place. But, that being said, during storms, broken tree branches can bring down power lines and create serious public safety concerns like damaged equipment, fires, and power outages. Vegetation management, commonly known as tree trimming, identifies hazards and fixes them by pruning trees and redirecting growth away from power lines. All the while, making every effort to ensure trees remain healthy. Highly skilled arborists trim and cut trees near electrical equipment and wires based on tree species growth patterns, geography and line voltage. This work has resulted in reducing power outages by 40% in Ottawa. In fact, between 2019 and 2020, tree contact with power lines was the cause of only 7% of all outages. This is in large part thanks to the preventive measures that utilities like Hydro Ottawa take all year long, with the extreme weather events we've witnessed in the past years, and as climate continues to change, the outcomes will create more problems for utilities to provide reliable power to customers without extended outages. So here's today's big question: In the age of climate change and environmental responsibility, how can utility companies strike a balance between maintaining reliable service, minimizing outages and maintaining a healthy and vibrant urban forest? To help us better understand this balancing act, I've invited our Supervisor of Distribution Operations at Hydro Ottawa Nick Levac and one of the Forestry inspectors, Greg Tipman. Welcome to you both. Greg, I'll start with you. Can you tell us a bit about your work and what the biggest misconceptions are about tree trimming and vegetation control programs when it comes to electricity?


Greg Tipman  05:06

For sure, Dan, and just again, thanks for having us on your podcast this morning. It's getting kind of meat potatoes, you know, my daily job encompasses speaking with customers, addressing the vegetation concerns around power lines, auditing of the contractor we use, which is Asplundh Tree Service. There's also coordinating of our jobs, our time and material jobs. So it's stuff that I look at and deal with the customer and then gets delegated directly to a secondary crew to do that specific work for the customer. There's also writing of prescriptions for any work for other jobs for the customers. So specific work they want Hydro Ottawa to do that's outside of our regular trim program. Some of the biggest misconceptions that I've run into is that a lot of the public thinks that our tree work is just a hack and slash that there's no thought or science put into the tree trimming that's actually going on, when in actuality, we have a whole set of standards for proper pruning, and tree trimming of the species around the Hydro wires. And that kicks back to our working procedures or our lifeline clearing techniques. And then there's another misconception that I've run into quite a bit: a lot of people think that for us, or for our contractor to do the tree trimming, the power has to be shut off every single time. And that's, that's not the case. We like to keep it as a very rare scenario when we do have to shut the power off. And that's usually just for a safety issue for the for the tree trimmers.


Dan Seguin  06:56

Okay, Nick, we often say that trees and electrical wires don't mix. What types of dangerous situations can occur if they come into contact with one another? Is there maybe a recent example you can share with us?


Nick Levac  07:14

Yeah, so I mean, first in mine is obviously power outages. That's kind of the first thing that we hear about when a tree comes down on our conductors. But, you know, the power outages can vary from a whole circuit right back to a substation to just a localized outage in your community or along your streets. The other thing, if the tree does come down on the line, and our in our system doesn't experience an outage, oftentimes trees can catch on fire. So we've had, we've had examples over the years where a tree is rested on a line, nobody notices it, and then eventually, it'll catch on fire, which, which obviously can cause other issues. And especially in the summertime with dry conditions. If that does come down to the ground, I could, you know, start forest fires, which, unfortunately, our neighbors in the south of us have experienced down in California and stuff, but there was one larger outage. And I think it was a start in November, November 2, where a spruce tree that was quite a bit away from the line did fail, and it came down and took down two conductors out at the end of my road, I believe it was and it caused a large outage. In a sense, those are almost better to have because it's easier to find that tree and where the problem is, and we can get crews out to fix it in a quick manner. But that's probably the most recent one that we found that had a major outage and a big impact on system.


Dan Seguin  08:49

So we're clear, Nick, what are the guidelines that determine if tree trimming or vegetation management near power lines is required? What does sufficient clearance from electrical equipment look like?


Nick Levac  09:06

Yeah, so like Greg mentioned in the first question there, we have our arbors going through our system, and we're looking at standards that we trim to the city is divided up into about 30 vegetation management zones. And they're divided into either a two or three year trim cycle, which means you'll see arborist in your backyard or on the streets, trimming out to our guidelines, either every second year or third year. Our main goal, there's a couple of them. But our main goal when we're trimming to our standards that we have is when we come back and either two or three years, the vegetation that we trimmed out is still three feet away. There's different zones that we have from 10 feet back to the conductor or the live overhead wire, and from the wire out to three feet is called the restricted zone. And as I mentioned that that's where we do not want the vegetation to get into. Because if we, if it does get in there creates a bunch of different problems for our, for our tree arborist to go in there. And as Greg mentioned, outages is the last thing we want to do when we're trimming trees. And if that vegetation does get into that restricted zone, increased outages for trimming, there is an option that we have to look at which we're trying to avoid. So that's, that's kind of our main goal. We look at the species of tree and how much it would grow in a year. And as the arborist comes through, they're going to trim back that many feet. So if we have a fast growing species that grow, say, three or four feet a year, and we're going to be back in two years, we're going to trim that back three feet times two, plus the additional three feet. So we're looking at about a 10 foot trim on that.


Dan Seguin  10:49

Nick, pruning, and especially removal of interfering trees, often causes controversy. In an age of climate change and environmental responsibility, what do you tell folks that object to or have concerns about the important work you do to help keep the lights on and the trees safe?


Nick Levac  11:15

Yeah, that's a great question. We, you know, I think you hit the last word there. And your question kind of hits on our main goal of everything that we do here at hydro is safety. So not only we're looking out for the public safety, ensuring that trees aren't coming down on the line and staying energized. But we're also looking to know for worker safety. So as we're going through, we try to do preventative maintenance, so to speak. So very much like you get your oil change in a car, or you put your winter tires on this time of year, we're trying to trim trees away from the lines to make sure they don't come in contact that avoids outages, unplanned outages, especially because, you know, it's one thing to get a phone call to say, Hey, your power is going to be out because we're doing preventative maintenance, whether it's tree trimming, or upgrading electrical system, it's another thing to wake up at two o'clock in the morning, after lights out, heat off and everything and it's unexpected, and you're trying to get ready, your kids are at home or whatever. So preventative maintenance is the big thing. And we try to educate our customers that what we're doing out there is really just to make sure that we can decrease outages and especially those unplanned outages. The other thing that we look at when we're pruning trees is the tree health. And I know Greg's going to get into this I think a little bit later on. But just looking at the species a tree and how we trimmed them to make sure that the health of the tree is also a huge interest for our arborists that are up there. They're all certified trained arborist with some extra training on the electrical side, because obviously we're turning around live electrical lines. But when they get up into a tree, they're looking at the health of the tree. There's a lot of stuff once they get up into the canopy of the tree that they notice that you can't see from the ground. So they're taking into account and they're taking out any deadwood or anything in there and tried to not only like I mentioned before getting those clearances that we need for the electrical side, but also trying to enhance the tree growth away from our lines and looking at the health of the tree by taking the deadwood or anything out of it.


Dan Seguin  13:16

Okay, so back to you, Greg. I know you trim trees on public property that are within three meters of an overhead line. But what about on a private property? Trees near utility lines inherently carry serious risk to property owners who may be injured or killed when working on trees near power lines. What are homeowners responsible for? And when should they call us, the utility, to arrange for their help? Like a planned outage? Basically, what do homeowners need to know?


Greg Tipman  13:57

Yeah, Dan. So when you're speaking about kind of responsibilities on vegetation maintenance, Hydro Ottawa was responsible for the pole, the pole wire, and vegetation maintenance. The area around the high voltage wire that hydro trims as part of our responsibility is 10 feet from the primary which is usually the very top wire running pole, as well as about a three foot clearance around our low voltage or secondary wires. And again, that's the pole the pole wires just want to make that a bold statement. That's Hydro's responsibility as part of our maintenance package. Kind of like Nick was touching up on and that's that that happens, pending what grid what year, you know, two to three years central, within kind of the city core versus the outer rural areas. If a customer is looking to have work done on their tree which is growing out into their private property, and it's near our overhead wires, Hydro comes in free of charge, we get it clear 10 feet 10 feet back debris would stay on site. And then it would be the homeowners responsibility to either cut the tree down themselves hire private tree contractor, or if they wanted, they could also hire Hydro Ottawa, do our work for others program, and we would write them out a formal tree quote. And they would, they would pay an additional cost for that, that work that's outside of our regular maintenance scope. Now in regards to the wires running pole to house service wire, or if you're in a rural area, and it's a private primary wire, there's a couple options that they have for having those what those wires that vegetation trimmed out, they can either hire a private tree contractor, and Hydro Ottawa, or service department provides one free disconnect a year for any tree work. Little bit more legwork for the customer or the contractor to do, but it's an entirely viable option. The second option is they can again hire Hydro, to trim out their service wire to whatever specs we normally recommend it you know, it's a low voltage secondary wire to have about a three foot clearance on it, they want us to go with that option. I would write them out a formal tree quote, have all the details, proof of payment beforehand would be had. And then we would schedule in the customer an exact date. And they would essentially have the work done to what the quote was that they're paying for the work to be done and, and go from there. It's quite effective. We've gotten a lot of feedback from the customers about having their service wire trimmed down. And there's been a lot of good things to have come from having us on site. And just doing it all and not having to worry with them having to organize an outage on their house. So it's, it's been a good go.


Dan Seguin  17:03

Here's another one for you, Greg, went planting a young sapling, it's often difficult to imagine that in as few as 10 years, it could have a significant impact on the landscape with an expanding canopy as a homeowner or a landscaper. If you're planting a new tree, how important is it to contact your utility service provider? To discuss your plan? Do you have any tree planting advice? Or some good resources on what to plant? And where?


Greg Tipman  17:40

Yes, yes. So basically, Hydro Ottawa has a really good source on our internet page. Basically, just type in Google Hydro Ottawa Tree Planting Advice, and it's a pamphlet that's been put on to the internet and it has everything for suggestions of where the tree should be planted, what type of species is it? How tall? Will it grow? How wide will the canopy grow? How many feet back from an overhead wire should be planted? It has a breakdown of you know, species names, what soils are best to be planted in? You know, like I said, their typical growth structure in relation to overhead wires. And there's also advice given on planting around underground wires, which a lot of people you know, you don't see them, you don't really think they're there. But they are, you know, most people just see the, you know, the green box, the ground transformer, if you will, but where are the wires going? Which, which way Can I can I plant and whatnot. So it's a really great resource has a lot of information, a lot of diagrams. Definitely check it out. And then another great option would be just put a call in, have myself or Nick show up. And, you know, we can tell you, you know, basically where, what, what's the lay of the land? What is your yard showing you? You know, are there other trees in the neighborhood or in your yard, you can get a very good look just from seeing what's out there, what to expect. And then and then go from there.


Dan Seguin  19:29

Okay, we'll actually have for our listeners in the show notes. We'll have links to all of these publications and the actual section on the website. So definitely we'll drive traffic there. Because the last thing I think we want is for me to put your extension number, your mobile number and have 100 calls tomorrow.


Greg Tipman  19:51

There we go. I like push it all in there.


Dan Seguin  19:56

Okay, Nick. This next question might be in your wheelhouse. A power outage occurs when there's a direct contact between two conducting lines with face to face. Or by providing a path for electricity to travel to the ground. There are several other ways that vegetation, trees in particular, can cause power outages, wondering if you could expand on those causes and how utilities and folks in your profession mitigate that?


Nick Levac  20:35

Yeah, it's an interesting question. It's obviously something we look at all the time. And that's our biggest goal within our department is to mitigate those outages. And I actually came from a background in the lines department as a power line maintainer for 10 years and swung over and got into working with the veg. management program. And, you know, I'd say it's a really good partnership that we have right now, not only with, with Greg and our other utility forestry inspectors, but along with our contractor Asplund who's doing the work for us. And, you know, that's a constant conversation that we're having weekend week out. And not only are we reviewing any outages that might have occurred the week before and trying to follow up on those to see why those power outages occurred and how we can hopefully prevent them from reoccurring. But within the system itself, the electrical system, we have, it's very much like your house where it's set up where we have different circuits all the way through the city. And within each circuit, we have different fusing, the further you get away from the substation. So the fuse in coordination can really help out if you have a tree that falls at the very end of that circuit, we have the fusion set up in a way that it's only going to go back to the next device downstream. And if everything is working properly, that fuse will open up and it'll really shrink the size of that outage rather than going all the way back to the substation. So if you can imagine if you have 1000 customers on a circuit, and you have 10, different fuses all the way down, and that last one blows, you're going away affect 100 people instead of 1000 people. Also, within our system, we have devices called reclosers. So I'm sure many listeners have had their lights flicker on and off two or three times. And then unfortunately, after that third flicker, the power does stay off permanently. That means that there's a bigger issue on the line and that reclosure could self-clear. So those devices are there. For momentary outages, when they see a spike in amperage, they'll open up the circuit and give time for that tree or whatever that foreign interference is to clear itself. And then close back in with the hopes that once it closes back in that power will stay on. If it senses that it's still there, it'll open back up again. Hopefully allow it to clear a little bit longer closed back in again. And hopefully the second time's a charm. Unfortunately, sometimes that doesn't work. And then you experienced that outage, kind of the last kind of protection in the whole stream of protection devices is that circuit breaker back at the station. That's kind of the worst case if we see a circuit open up. That means that there's a major problem. Usually, like you mentioned there, there's a phase two phase kind of issue where two conductors have slapped together. And that's kind of what causes the biggest outage, that's when we know we have a large problem. And the other issue with that is because our circuits are so long, some of them you know, in the downtown core where we have more substations, it's a little bit easier to find because you know, the circuit might only be say a kilometer or two long, but if you get out into the rural Orleans, Kanata, down south - though, manotick, nepean area, you can have, you know, 10-15-20 kilometers a line. So, if your circuit breaker and your station opens up, that means that somewhere between your station and the end of the line is your problem. So there are fault indicators and stuff on your line that can help pinpoint it. But it definitely can make it more challenging when you're when you're starting back at your substation not having to patrol 20 kilometers a line versus if that fuse opens at the very end of your line, you know, okay, it's the last section within that line. The other thing that can really help us out is the customers in the field. So a lot of times we'll get calls in and it's great to get that information and Hydro Ottawa is very active on social media and that that definitely helps if, if a customer sees a problem if they see a line down if they see a bright blue flash if they hear a large loud bang. You know, first and foremost, let us know don't ever approach downed wires Stay away, even trees that could be leaning up against the wire. But I and I mentioned this before, just because the trees against the wire if that wire still energized that could potentially energize that trees, we want to make sure we stay back, you know. Stay back 10 meters from that tree stay back 10 meters from that electrical line because you don't know if it's on, or if it's still alive. So your safety is first and foremost, call in, call 911, if there's any, you know, immediate hazard fire, police can come in and assist, they will get a hold of our system office right away and direct us to that. Or if it's something that's, you know, a little bit less and you think that hydro should know, we have lots of different social media channels you can reach out on. And let us know. And that really does help because that information does find its way down to the crews in the fields. And it helps us get to the outage and find that problem that's causing the damage that much quicker.


Dan Seguin  25:51

Yeah, for sure. I know, historically, we've had customers actually send us photos on Twitter. Yeah, that we could actually send systems office so they can actually identify, they would know exactly where that is. And they helped out the guys on like the field workers.


Nick Levac  26:06

Yeah, no, that's, that's great. And I mean, I was, I was on that first response truck there 24/7crew for multiple years. And it was great. I mean, you know, when the days are getting darker and the nights it's in the middle of night, the last thing you want to do is be trying to find, find an outage and or the cause of an outage. And it's kind of like finding a needle in a haystack sometimes out there. So anything from the customers is a great help.


Dan Seguin  26:35

Yeah, definitely. Okay, in addition to being a qualified arborist, Greg, you also have extensive knowledge about electricity. Can you talk about this dual role and special qualifications that you have? How dangerous is your job? And do you work around live electricity at high voltage?


Greg Tipman  26:59

Yeah, Dan. So just a little background on my schooling and qualifications. I did my forestry technologist diploma at Algonquin - a two year program. And then from there, I moved out to BC to work on some really big trees. And while out there, I morphed into the utility side of tree work. And that's where I went and did my apprenticeship program. From there, you need approximately 4000 hours just to qualify, the program's a two year program, you've accumulated about 6000 hours around of live line clearing, working around the wires, you'll learn how it looks just all the basics, electricity, how it works, how to identify the equipment, that coupled with your actual tree work in the tree, the tools, special tools you'll be using, so dielectrically tools, how to operate bucket trucks, so on and so forth. Rigging big chunks of wood down in trees, how to do it safely, and all the while in close proximity to these overhead high voltage wires. It's very dangerous. I mean, you couple your, you know, 30-40-50-60 feet up hanging by ropes, you're using a chainsaw to cut wood. Plus, you have a live line that's, you know, five, six feet away from you. So it's definitely very dangerous. But the schooling, the on the job training that you get just, you know, old hands, showing you the techniques, the up to date, safety standards, and whatnot. It makes your comfort level something that would never, you know, come natural to you become second nature. So it's, it's definitely a process, it's definitely building the confidence over time. And then, you know, taking classes, learning whether it's through the International Society of arboriculture on the tree side of things for tree health, you know, one of the tree species tree biology pests, you know, a lot of times customers will ask, you know, why is my tree dying? What Why is it declining? A lot of times people will think, Oh, it's Hydro Ottawa you trimmed the tree incorrectly. Well, no, it's, you know, a pest infestation or you did some landscaping or whatnot, the roots have been killed and whatnot. So it's learning all that you know, information and coupling it and pairing it with the electrical side of things that it really makes for a harmonious job and, you know, a great aspect to keep learning There's always new information, new research coming out on trees and the electrical side of things you know, and then just basically, you know, having the resources also at Hydro Ottawa, it makes that partnership that much better for getting the work done and done safely.


Dan Seguin  30:24

So Greg, I've seen some amazing footage of folks in your profession climbing pretty high in trees. So besides not having a fear of heights. What's that like? And what's your favorite thing about your job? Have you ever been surprised by some birds or squirrels? Or, you know, have they surprised you? Or have you surprised them?


Greg Tipman  30:49

Yeah, so kind of, like I was touching on there. I mean, the fear of heights is not was never really the big deal. It was more trusting your gear. Knowing that you know what a 10-12 millimeter diameter rope is going to hold you and your gear. You know, it's going to hold, you know, wood swinging around and whatnot, it's not going to break off, you know that your knots have been tied correctly, they're not going to come undone, you're going to fall to your death and get injured or whatnot. Those were kind of the first fears to really get over. But once you get that it's practice, the more you do it, the more you get comfortable doing it. The more you feel safe and secure. I've definitely had some weird, interesting animal encounters while working in the trees. I've had birds land on my head and stay there while working. I've had raccoons, you know, climb out of hollows. I've had bats, you know, fly out from underneath bark. But probably the scariest was wasn't in the tree yet. But we're doing some ground slash in BC and probably 10-12 feet away. A black bear just goes running right by and yeah, it was exhilarating. But it was done in a flash and yeah, nothing. Nothing more. But you know, it definitely, you know, could have been a different interesting situation had it been a, you know, an angry bear, if you will. Yeah, for the most part. It's the job. You get to see nature all the time. And there's always something great to see, animal wise.


Dan Seguin  32:33

Cool. Okay, both. Are you ready to tag team here and close us off with some rapid fire questions?


Greg Tipman  32:43



Nick Levac  32:43



Dan Seguin  32:45

Greg, what is your favorite tree?


Greg Tipman  32:48

Can I give you four Dan?


Dan Seguin  32:51

Sure. Why not?


Greg Tipman  32:53

So Eastern white pine. The monkey puzzle tree. Giant Sequoia and the Charlie Brown Christmas tree.


Dan Seguin  33:03

Okay, that's good. Yeah, we I might ask you to provide the links. So I can direct listeners to those trees. Nick, what is one thing you can't live without?


Nick Levac  33:18

That's an easy one. It's got to be my family. My two girls at home my lovely wife and, and probably a good cup of coffee or a nice Americano in the morning just to get things going.


Dan Seguin  33:29

Cool. Greg, what habit or hobby? Have you picked up during shelter in place?


Greg Tipman  33:37

Probably flying and crashing my drone.


Dan Seguin  33:43

Okay, yeah.


Greg Tipman  33:44

A little more practice.


Dan Seguin  33:47

Yeah, more practice! Nick, if you could have one superpower, what would it be?


Nick Levac  33:56

Ah, you know what I think never to age physically. Only in wisdom. The body's getting a little bit older and every you know, every time I go out and try to play hockey or do something now I wake up a little bit sore in the morning so I could keep my physical health. Maybe back when I was in my 20s. That would be amazing.


Dan Seguin  34:17

And what about you, Greg?


Greg Tipman  34:25

Maybe just unlimited superpowers.


Dan Seguin  34:28

All of them,


Greg Tipman  34:29

All of them!


Dan Seguin  34:30

Okay. Back to you, Nick. If you could turn back time and talk to your 18 year old self. What would you tell them?


Nick Levac  34:40

You know, I'd probably try to let them in on a couple of neat, you know, world events that were going to take place between then and then when they're my age now and just make Tell him to go there. Make sure he's present and no matter what the cost is. Sometimes you only get a once in a lifetime chance to see things and make sure he gets there to experience that life live.


Dan Seguin  35:05

Okay. And lastly, this one is for both. What do you currently find most interesting in your sector? I'll start with Greg.


Greg Tipman  35:15

It's a, it's really the day to day change, there's always a different challenge that's coming up, you're always in a different location dealing with different people. So it's never, you know, a monotonous job, it's, it's always fluid, there's always something new.


Dan Seguin  35:34

Okay, what about you, Nick.


Nick Levac  35:35

I, what excites me the most coming down the pipe, I think is the technology that hopefully we're going to be exposed to, I mean, Greg mentioned, crashing his drone, but you know, just even stuff like that, and us being able to fly over our overhead lines and really take a good snapshot of what that vegetation looks like within our city. And, and what we can do to kind of have a good mix between, you know, maintaining that urban canopy in Ottawa, and then also at the same time keeping the electricity on and if we can use different types of technology that's coming down the pipe to find a balance between the two that we can get out and, and proactively trim trees because we know exactly where they are. And also keep that urban canopy for that for customers here in Ottawa. I think there's a there's an interesting mix coming down, how we can leverage that technology to our advantage.


Dan Seguin  36:27

Okay, Nick, Greg, we reached the end of another episode of The ThinkEnergy podcast. I hope you had a lot of fun. And thank you very much for joining me today. I hope you I hope you enjoyed it.


Greg Tipman  36:42

Thanks again for having us, Dan.


Nick Levac  36:44

Yes, thank you, Dan.


Dan Seguin  36:48

Thank you for joining us today. I truly hope you enjoyed this episode of The ThinkEnergy podcast. For past episodes, make sure you visit our website hydroottawa.com/podcast. Lastly, if you found value in this podcast, be sure to subscribe. Anyway, this podcast is a wrap. Cheers, everyone.


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