A smoke column shows the air conditions during Oregon's Bootleg Fire on July 18.
U.S. Forest Service via Inciweb
Scientists from the U.S. Forest Service have analyzed the soil in the area burned by the Bootleg Fire for danger of erosion. The Klamath Tribes are concerned that the rainy season will bring large amounts of sediment and nutrients from the burn area into the Upper Klamath Lake, which is already having problems with toxic algae blooms. Alex Schwartz, environmental reporter for the Klamath Falls Herald and News and Report For America, wrote about all this in a recent article.
This transcript was created by a computer and edited by a volunteer.
Dave Miller: This is Think Out Loud on OPB. I’m Dave Miller. The Bootleg Fire, which at one point was the largest wildfire in the U.S., is now fully contained. In the end, it burned more than 400,000 acres in southern Oregon. But while the dangers from the fire itself have passed, the effects of that fire will linger in the region for a very long time. One of those effects is the possibility of sedimentation, increased runoff into the streams and rivers that feed Upper Klamath Lake.That could mean more devastating algal blooms. Alex Schwartz wrote about this recently for the Herald and News in Klamath Falls and he joins us now to talk about it. Welcome back to Think Out Loud.
Alex Schwartz: Hey, thanks for having me.
Miller: So it’s hard and irresponsible to talk about the cyanobacterial algae blooms without talking about the endangered fish that are being threatened by them. So, let’s start there. Can you remind us how significant the C’waam and Koptu species are for the Klamath Tribes?
Schwartz: The C’waam and Koptu are a type of lake sucker, pretty common in the remnants of these huge inland seas that used to dot the western U.S. They have been a huge food source for the Klamath Tribes for thousands of years. Every March, pretty much after the end of a really long cold winter, millions of these fish would run up the rivers in the upper Klamath basin to spawn. That was a really major food source, probably the first fresh food that most tribal members would eat traditionally at the start of their year. So they have a huge cultural significance and they’re just an important food source that the Tribes have not been able to harvest for coming up on 50 years now.
Miller: One of the reasons in more recent years for population problems with these fish is the big cyanobacterial algae blooms. We’ll talk about how the Bootleg Fire has increased the fear and the risk of even worse blooms. But they’ve been happening for years now. What are the existing reasons for these blooms?
Schwartz: The blooms are partially a function of how much phosphorus enters the system. We’re in a pretty volcanic area. The soils are naturally highly rich in phosphorus, and that nutrient is harnessed by two species of algae that have sort of come to dominate the community in Upper Klamath Lake. The lake has always been nutrient rich naturally. It was never a beautifully clear Tahoe kind of situation, but it has gotten worse than normal since colonization and that’s largely due to the channelization of rivers upstream of the lake. Cattle that have trampled the soils into the river and caused more erosion. Also fertilizer runoff from agricultural production above the lake. Every time there’s more erosion or increased erosion, more nutrients entering the river, that’s bad news for these blooms and then ultimately the fish. The blooms themselves are toxic to humans and pets, but the studies have been done and they don’t really show to be directly toxic to the fish. The problem is that the blooms dominate the entire system and then all die at once and that causes massive, dramatic swings in water quality. So the oxygen gets pretty much sucked up by the decomposing algae cells and that really stresses the fish out. Then they end up succumbing to parasites or get predated by birds.
Miller: So let’s look forward now to the heart of your most recent reporting. What are the specific fears about why the Bootleg Fire could lead to even worse algal blooms?
Schwartz: After wildfires, a concern is sedimentation. This is common everywhere, not just in the Klamath Basin. What most people are usually concerned about is, is somebody’s house going to get washed away in a flash flood or is there going to be a debris flow blocking the river? Here, the concern is really how much additional erosion are we going to see? How much more soil is going to enter the rivers and by extension, phosphorus, than would have happened without the fire? So that’s the real concern here. Once you have a burned area, the soils are loose, trees have died, they have uprooted the soil if they’ve fallen down. Just the top layers of soil have burned in some areas. And then when you get a really major precipitation event on top of that, you’re just pretty much washing all of that soil into drainages which eventually enter the rivers.
Miller: Just how big an area are we talking about?
Schwartz: Well, as you said, over 400,000 acres. So it’s something like 80% of one of the rivers that feeds into Upper Klamath Lake was contained within the burn area and then, maybe around 50 or 60% of another river. So it’s a major chunk of this watershed could be affected at least by the sediment loading.
Miller: You note in your article that when soil burns, it can become hydrophobic, meaning that among other things, water is less likely to soak into the ground, to go down deeper. What are the implications of that?
Schwartz: Yeah, so that also has implications for spring output in other areas of the system. If you’re not having soil soak up the water, you’re not storing that water for the dry season. That could make things harder to regrow after the fire. Then it also has issues with charging the aquifer, which studies have shown that pretty much the entire upper basin is connected via this underground aquifer. So having less recharge into that has implications even for things other than the sediment loading concern.
Dave Miller: Which could be tied to things, for example, like people’s residential or agricultural wells not recharging, and those are wells that were drawn on much more in this past year than in previous years. You reported that the Forest Service sent a team known as a burn area response team to the area recently to do some surveying to see what’s happening. What exactly were they looking for?
Alex Schwartz: They’re really concerned with immediate threats to life, property and natural resources. And it’s this kind of outside team of hydrologists, biologists, just a bunch of different Forest Service scientists who come in and spend a couple weeks driving to as many places as they can, flying over, taking measurements on the ground and then modeling what the effects are. This was such a huge area that they took data on the ground and then used a model to reconstruct how things were impacted across the entire acreage of the burn scar. They were looking at a number of things, but in terms of sedimentation, the concern was topography and soil burn severity. So, if you see how much the soil has burned, you can see how loose it is and how likely it is to erode into drainage when a precipitation event arrives. Topography also affects that. If it’s a really steep slope and high burn soil, rain is going to get on that and it’s all going to wash into the drainages, and you potentially have a landslide on your hands.
Dave Miller: So based on your reporting, it seems like this team [was]... maybe, pleasantly surprised is too positive a way to put it... but less disappointed, less worried than they had been going in. It was a less negative picture than they were expecting. What exactly did they say?
Alex Schwartz: Right. So the soil burn severity was either low to moderate for a large portion of the burn area, which you don’t typically see when you have a fire this intense. What they told me happened was the fire burned so quickly, torched a ton of trees. [It] mainly spread through the crown of trees in some places, but didn’t quite reach all the way down to the soil. So that’s a good thing in terms of keeping the soil intact and preventing erosion. But you have the Tribes who are just concerned [about] any additional phosphorus entering the lake.
Dave Miller: Right. It seems like, at least, the Natural Resources Director for the Tribes was critical of the Forest Service finding. What was his complaint?
Alex Schwartz: Yeah. So it was more critical of the purpose, of the analysis. They pretty much did what they were supposed to do. They didn’t report anything incorrectly. But you have people outside the region that are coming in to do this work, and they don’t really have the concerns that people on the ground might have. So they weren’t really looking for ‘what is the effect going to be on these endangered fish many river miles downstream outside of the burn area?’ That wasn’t really the scope of the report. So I think the concern was, the public is going to read this and they’re going to think, oh, it’s not that bad. But we, as the Tribes, are still concerned about it.
Dave Miller: How much time do the Tribes or state or federal officials have before it gets really critical, before there’s serious runoff and sedimentation that could hit the rivers?
Alex Schwartz: Really, it’s the first. If we have a major precipitation event in the fall or once the snow starts to accumulate on the ground there, they can’t really do any work if it’s snowy. They have to get it done before we have a melt event or a rain or snow event that will release a ton of water into the system. So it’s pretty much as soon as possible is [the] timeline they’re working on.
Dave Miller: What can be done, especially if we go back to this point that we’re talking about, just hundreds and hundreds, hundreds of river or stream miles?
Alex Schwartz: One of the things that I thought was most interesting that they would do is create beaver dam analog. So just try and come up with natural blockages or not necessarily to completely block the water, but to slow it down so that that settlement has time to settle out before it enters a major tributary. They’re identifying these smaller rivulets in the highland to block up and slow the flow of that water. That’s what would have been present naturally back when we had an abundance of beavers in the system. So it’s trying to replace them and mimic their activity. It’s also looking at forest roads, making sure that those don’t further contribute to sedimentation, making sure that there’s adequate drainage on the sides of those roads as well.
Dave Miller: Who is actually going to pay for this work?
Alex Schwartz: That’s the question, right? A lot of the land belongs to the Forest Service or these private timber companies. It doesn’t belong to the Tribes, but they still have sort of a management agreement with the landowners in the area, or at least the major landowners in the area. I know that they’ve applied for emergency funding from the state. They’re concerned that that’s not going to come in time. I think there’s also something available through federal dollars through the Forest Service, but I know that acquiring that funding to do that work is definitely a challenge.
Dave Miller: Alex Schwartz, thanks very much for your time today.
Alex Schwartz: Thanks so much for having me.
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