Water We Doing?

Wildfires and Water; Isn't the Problem Over when the Fire's Out?

April 19, 2021 David Evans / Dr. Kevin Bladon Season 1 Episode 6
Water We Doing?
Wildfires and Water; Isn't the Problem Over when the Fire's Out?
Show Notes Transcript

Is it just me or do we seem to be getting bigger more devastating wildfires every year? If it isn't fires across Canada, it's California, it's Australia, and it's even the Amazon rainforest. Is this more than normal and should we be worried?

Wildfires are a natural part of many forests systems and help maintain forest health, but when we put out fires too quickly we can end up creating bigger fires for ourselves in the future.

In this episode we will be discussing the effects that wildfires can have on our freshwater systems. We'll discuss the benefits, the negatives and how we should be reframing our conversation about wildfires on our landscapes. in this episode you will hear from Dr. Kevin Bladon from Oregon State University who studies how freshwater systems react after wildfires.

Are you interested in getting more involved in managing your local watershed? If you live in Alberta you can find out which one you are a part of at the Alberta Watershed Councils website! Our local watershed councils are a fantastic resource to learn more about our natural areas and how to get involved on a regional scale!  Whether it's the Athabasca Watershed Council , the Bow River Basin Watershed Council or the North Saskatchewan Watershed Alliance they are all fantastic organizations to get involved with.

To learn more about Dr. Kevin Bladon, his lab and the important research they are doing you can check out his lab website  right here the FEWS Lab.

Interested in the effects of fire on Fort McMurray's drinking water? Click Here!

The Aquatic Bisophere Project
The ABP is establishing a conservation Aquarium in the Prairies to help tell the Story of Water.

Disclaimer: This post contains affiliate links. If you make a purchase, I may receive a commission at no extra cost to you.

David Evans:

It seems like almost every year, there's more and more wildfires that are making headlines across North America. California is burning Alberta is burning BC is burning. And we are way too familiar with it here in Alberta looking at Slave Lake, and more recently, the Fort McMurray fire. Now wildfires are a natural part of our landscape, they're supposed to happen, the boreal forest typically will burn every 100 years. It's a forest that's actually shaped by fire fires makes sure that there is a diversity of species and different ages of different species, so that we don't have one blanket species that crosses an entire area and isn't susceptible to a disease. It also makes sure that there's many different habitat types, so that we can have all of these different species within our biodiversity that can live nearby. There is one thing that's maybe not talked about that much when it comes to wildfires. And that's what are the impacts from a wildfire? on our native freshwater systems. Today, you'll hear from Dr. Kevin Bladon, from Oregon State niversity. As we discuss what appens after the fires out to ur freshwater and how we can ave impacts for decades after he fact. Today, we're learning ll about wildfires impacts on ater. water we doing? And how can we do better? your one stop shop for everything water related from discussing water to use and the organisms that depend on it for all the global issues that you really never knew all had to do with water. I'm your host, David Evans from the aquatic biosphere project. And I just want to ask you something. What are we doing? And how can we do better? It may surprise people to learn how many fires actually happen every year within Canada. So in Alberta alone, between 2006 and 2018, we had almost 20,000 forest fires. That's only in the province of Alberta. And 61% of those fires were linked to some type of human disturbance that created the fire, whether it was a cooking fire that wasn't put out properly, or it came from industry in some way. Now, most of these were really small. But some did get really big. The largest of these fires was known as the Richardson fire. And if it gets a name, even though it's a big fire, this fire burned 577,646 hectares. So to put that in perspective, that's bigger than Prince Edward Island that was just north of Fort McMurray around the oil sands. So across Canada in general, we typically see about 8000 forest fires every year. And it works out to about 50% of these being created from lightning strikes to begin with. Now as our population grows and our cities expand, and we start to build houses in more rural areas, we start to encounter more and more wildfires. Now what's typically happened is, we like to be able to put out wildfires as soon as they pop up, because we don't want to have them take out someone's house or take out a building or an industry of any kind. We want to protect our forests because we use that to harvest to create pulp and paper. But it's a delicate balance we have to strike because this is a natural process. Many of the forests within Canada burn on a regular basis so that they can maintain their own health. If we put out these fires too quickly and don't let it burn a little bit, then we're messing with that cycle. I like to think of it as if you had a pile of sticks and you added a stick every day. You burned that pile every 10 days, then the pile would be manageable. But if you waited a year, you would have a huge fire. And that's what forest managers are trying to avoid, because we have to balance protecting everyone's households and livelihoods. But also make sure that we don't put ourselves into a situation where we get these catastrophic, huge fires that we can't control. So wildfires happen. But what happens after the fire four years after the wildfire that swept through Fort McMurray, Alberta, this fire in 2016 was over 6000 square kilometers of burnt forest. It burned through 2400 buildings in the city of Fort McMurray and 88,000 people were forced to evacuate. It's costing an estimated $10 billion of damage. The city of Fort McMurray sits right on the Athabaskan river, researchers from the University of Alberta were flown right to the town after the fire to see if the drinking water was still okay. And they quickly noticed that every time it rained, there would be huge increases in the amount of ash, potassium, nitrogen, calcium, and really dangerous heavy metals that would spike in the water. So it seemed that every time it rained, all of that would be washed into the Athabaskan River. Now the drinking water is still okay to drink. But it has really increased the amount of work that goes into making sure that the drinking water is okay. It's actually increased the cost of purifying that water by 50%. And that continues to this day, Fort McMurray is still dealing with that at their water treatment facility to make sure that the citizens have safe drinking water. And as climate change increases our fire seasons in our overall temperatures, we're going to have more and more fires. And as our population grows, we're going to be encountering fire more and more on the landscape. So we need to understand how this impacts our most important commodity freshwater. So I went to the expert. Kevin, do you mind introducing yourself?

Dr. Kevin Bladon, Oregon State University:

Sure. Thanks for having me. First of all, my name is Kevin bladen. I am an associate professor of forest hydrology at Oregon State University. I know a lot of your audience is going to be in Alberta. Why would you talk to somebody from Oregon State? Well, I'm an Alberta boy. I was born and raised in Sherwood Park and went to the University of Alberta. I left to the British Columbia for some years and came back and spent a lot of time and so I'm very familiar with with Alberta and done a lot of research there.

David Evans:

Kevin studies how different disturbances to forests can impact watersheds. So this can be from mining from forestry, and also from wildfire. And that's what we're going to be talking about today. So Kevin, what are the effects after the fires done to our water systems? Yeah,

Dr. Kevin Bladon, Oregon State University:

I'm so glad to hear that we're having a chance to talk about this. And you know, I think with fires and the issue with smoke, that gets people's attention, right, and people are concerned about fires. And we here in the Pacific Northwest this past year, we had a couple of weeks where we were trapped in our homes and taping up around our doors to keep the smoke out and all that

Unknown:

fire is gone.

Dr. Kevin Bladon, Oregon State University:

And the smoke is gone. And to a lot of people, their brains have turned off and go Okay, all the problems are over well as a hydrologist and thinking about water. This is when all of our problems are starting. And those problems can be really long lasting longer than people think. No, we may have issues after large wildfires that persist for decades. So what are the aims there's there's so many that we can talk about first, I guess the first thing that comes to mind is just simply water supply itself, the amounts of water, you remove the forest canopy, you burn that forest canopy, well now those those trees themselves are not transpiring or using using water. Also, when when it rains or snows it doesn't fall on the canopy any longer it hits the forest floor. And so you've got more water hitting the forest floor, the forest floor has also changed and burn because the organic matter. And so that's going to deliver more water more often more rapidly into our streams.

David Evans:

So you might be asking yourself, but why would it matter if snow is falling onto branches or falling onto the forest floor is still the same amount of snow. It's the same amount of water. It's just landing in a different place. But what's really crazy is that we have this concept called interception loss. And basically what that means is that if the snow is falling onto branches on the trees, it's higher up in this snow 25 to 30% of it well actually be evaporated back up into the atmosphere. And so that snow is just gone, it doesn't make its way ever into the streams. But when the branches have been burned away, but they can't catch that snow, then all of that snow lands on the forest floor and it stays there. And this means we have an extra 25 to 30% of water flowing into our streams that we weren't expecting.

Dr. Kevin Bladon, Oregon State University:

Those peak flows that we might see or the flooding events, those can lead to increases in erosion and movement of a whole bunch of constituents that we could talk about downstream. Also, a bunch of our infrastructure downstream is all engineered, based on, say historical flood events. And all of that can create a whole bunch of issues as well that are really expensive. timing of flow is is something else in terms of water availability, something people don't think about. So communities that rely on say reservoirs to hold back Water, water managers, they kind of think about way, when do I hold back water? When do I release water for aquatic ecology, wildfire can increase the timing of the delivery of that water by a couple of weeks, that really throws our water managers for a bit of a loop. And then but one other thing that's really emerging right now, and it's got people concerned, we've done research on harvesting sites, where we have long term data, we're 5060 years after forest harvesting, what we've been able to see and illustrate is that those younger trees 5060 year old versus the 200 year old tree is are much more vigorous in their water use. And that has led to low flow deficits in the summer. So when our fish need water in the stream, the trees are using far more water those younger trees, leading to less water in the streams. With implications for aquatic ecology, I think about a large, catastrophic wildfire that burns 20% of an entire basin. That's a massive turnover of vegetation and potential long term implications for water supply.

David Evans:

This difference between young trees using so much water and older trees, not needing as much is really interesting, I like to think of it as the younger trees are just growing into their bodies, they don't know how to be efficient with what they've got. And they're just going to soak up whatever they can, or the older trees, they've kind of got to figure it out. And they don't need as much. So this really makes an impact when it's a huge, huge area. First, we were talking about too much water right off the bat. And now we're talking about not enough water later on in the summer when we really need it. And fires don't only impact the amount of water we get in our systems. But it also impacts the quality of that water. Because when all of the plant life is burned away, the next thing to go

Dr. Kevin Bladon, Oregon State University:

is all of that topsoil, the things that probably come to most people's minds that we haven't talked about yet erosion movement of sediment downstream. A classic example of that is the 2002 Haman fire and Colorado, where the year after that fire precipitation events moved enough sediment to fill their reservoir, the size of a football field 61 meters deep. So there's a lot of sediment and for them to dredge that and pull that sediment out of that reservoir that cost them about$30 million in taxpayer money. It's pretty

David Evans:

crazy to think that a raindrop falling out of the sky could hit the soil with enough force that little pieces of dirt get swept away in that water droplet and then end up in our streams in our reservoirs and further and further down into our rivers. And this is how erosion really starts. So if you don't have a branch that blocks that raindrop coming all the way down, and it just hits the soil directly, then you're gonna start to lose a lot of that soil. Also think about this. What do roots really do? roots hold soil in place. So when fires go through and the root systems get compromised, the root systems die off, we start to just have soil falling off the landscape, and especially in mountainous areas, that soil is going downstream. Fast. And then with

Dr. Kevin Bladon, Oregon State University:

that, we're going to see movement of things like nitrogen and phosphorus and carbon, sort of the building blocks of our aquatic ecosystems, moving into those systems and really changing our aquatic ecology, as well as other constituents of concern like heavy metals moving into our stream so lots going on after wildfires that can impact our water security.

David Evans:

What is nitrogen and phosphorus Basically, you can think of this as the fertilizer you would put on your lawn or in your garden. It's really what stimulates plant growth. When we lose this fertilizer from our landscapes, and they run into our water systems, it has two effects. So firstly, all of this can lead to increases in primary productivity. And really, what that means is it can lead to algal blooms. Now, when we put more nutrients into an area, then it allows more organisms to grow. So it starts off with algae. And that increases the amount of little critters invertebrates that can feed on that. And then it can lead to increased numbers of fish, and so on and so on. We start getting into trouble when we have too much nitrogen and phosphorus flowing into these water systems. And we have huge algal blooms that are completely out of control, some algae can actually become really harmful to humans becomes toxic, and then we don't want to be drinking or swimming in it at all. When algae blooms up so much that there's nothing left to eat it, it'll start killing itself off, there's just too much of it. And when it starts to die and decompose, it uses up the oxygen that's stored in the water to decompose. And this then affects fish plants and other invertebrates because everything living underwater still needs oxygen dissolved in that water to survive. So all of this going into the water is good in low amounts. But it can be really bad when it gets to high level. But all of this has been washed away from a forest that has been burnt. So what about that forest, all of the nutrients that they need to live and grow big and strong, aren't there anymore? Well, it is all part of the natural cycle. But with erosion, increasing the amount of runoff of all of the important fertilizer nutrients that we need for forest to grow strong, it can take a long time for them to grow back. Now, if we start talking about how water is used to fight fires, it's also really interesting to know that we've already talked on the show about invasive species. But did you know that we can't actually use every body of water to fight a fire, you have to be really selective.

Dr. Kevin Bladon, Oregon State University:

We have folks in our government agencies who are actively identifying those different potential sources of water that we have for fighting fires. Why are all of our legs usable? Well think about some of the other issues we have right now in many of our lakes, we have invasive species, we have harmful algal blooms. And we don't want to be scooping that kind of water up and spreading invasive species around that we haven't thought of. So actually, we thoughtfully spend the time to identify what sources are actually usable for fighting fires. And those are pre identified for for fire suppression efforts.

David Evans:

That's a shout out for everyone who was still thinking about Asian carp from two weeks ago. I was so excited when Kevin actually said this because it's something I'd never considered. You can't actually go to every single Lake because what if a fish made it through a journey in a helicopter and got dumped onto a fire and got into a new system? Of course, that's how invasive species spread. I was so interested that they're actually taking this into consideration when fighting fires, because it seems to be a knee jerk reaction, we need to put this fire out as quickly as possible. And speaking of putting fires out. At this point, you might be thinking are wildfires. Good?

Dr. Kevin Bladon, Oregon State University:

That's a really important question. And the simple answer is yes. And I think it's important that folks hear that I think we've gotten used to like you say the sensationalism, we really frame fire as bad. And and certainly there's some negative aspects of wildfire. But fire is a natural disturbance. It's been a on our landscapes and helping to shape our landscapes for millennia. And well, before we were here, we have really influenced that fire regime and in in a lot of ways, and I think it's really critical for us to actually think about the positive benefits of fire. You know, certainly we have a lot of species, for example that are adapted to fire and actually need fire to come through. You know, certain pines have certain this Cohn's thing that needs heat from fire to release the seeds to continue to produce new trees and fire can release a lot of beneficial nutrients. It was key building blocks for our systems, nitrogen, phosphorus, carbon, yes, with too much of it can be a problem. But those little boosts of those nutrients into our system can really have positive outcomes for our aquatic ecosystems. And they actually seen a lot of systems around where we go out and they've retained all of the riparian vegetation and you walk in and is dense. Dark Forest and there's no light getting to the stream, you start picking up rocks and looking at the the stream bed and there's, there's nothing, there's nothing growing there. There's no primary productivity, there's no invertebrates, it's not suitable fish habitat. So just leaving things alone and and, you know, snuffing out all these fires because we think fire is bad. You know, in some ways, it's it's not a good thing we need to become comfortable with fire. We certainly don't want the large catastrophic fires. But we need to be comfortable with fires on the shoulders of the season and really see the benefits. There's so many ways that wildfires are beneficial. We just, we just need to get comfortable with that.

David Evans:

Thanks for tuning into today's episode all about wildfire and water. And thanks also to Kevin Bladon, for taking the time to speak with us for this episode. I really appreciate it. And it was a great conversation. Thanks again, if you want to get involved in how your watershed is managed, I'll leave a link to all of the different watershed councils in Alberta, down in the show notes because there's some really fantastic work that's going on by all of these different regional councils. So be sure to go check that out and find which one is closest to you. Also, there will be a link in the show notes to Kevin's lab, the FEWS lab, and all of the work that they're doing on wildfire and its impacts on water systems. I'm the host and producer David Evans and I just like to thank the rest of the team from the aquatic biosphere project specifically to Paula olman, Sophie Cervera Anna Bet ini thanks for all of your h lp. To learn more about the a uatic biosphere project and w at we're doing here in Alberta t lling the story of water. C eck us out at www.aquat cbiosphere.ca. And if you hav any questions or comments abou the show, we'd love to hea them. Email us at conservatio@aquaticbiosphere.org. Please do't forget to like, subscribe an leave us a review. It really he ps us out. Get excited for ne t week's episode as we talk ab ut the future of food. We're go ng to examine some different fa ming techniques that are re olutionizing how we interact wi h water and can use it to pr duce food. You'll hear from th team from Pontus Proteins an aquaponics company out of Va couver. And you'll also hear fr m Mike Williamson from Ca cadia seaweed on how seaweed is changing the game when it co es to seafood. Tune in you wo't want to miss it. Thanks an it's been a splash