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Drove the Chevy to the Levee - The Geology of Levees · PlanetGeo: The Geology Podcast

• 0:02
  SPEAKER_01: Welcome to Planet Geo, the podcast where we talk about our amazing planet, how it works, and why it matters to you.
• 0:16
  SPEAKER_01: Chris, uh, you you're just complaining about your only having two screens instead of three or four that you normally have.
• 0:24
  SPEAKER_01: Your setup is a little bit uh is a little bit amiss over there.
• 0:27
  SPEAKER_01: I hope you can bring your game and fight through it.
• 0:30
  SPEAKER_01: Those of us who have one screen on our setup, hope that you can really grit your teeth and bear it and record with two screens in front of you only, Chris.
• 0:39
  SPEAKER_00: So I I gotta talk to you about something.
• 0:42
  SPEAKER_00: So after school today, I'm a I'm a high school teacher, right?
• 0:45
  SPEAKER_00: And I I get this email about this kid, you know.
• 0:47
  SPEAKER_00: So I go down to the principal's office, the assistant principal's office, and I walk into in there, and he's luckily he's in there.
• 0:53
  SPEAKER_00: So I'm like, hey, what's going on with this kid?
• 0:55
  SPEAKER_00: And I'm looking around as he's talking because he was like really jabbering, and so I lost attention.
• 1:01
  SPEAKER_00: And I'm like, oh my god, he's got three screens around his desk.
• 1:06
  SPEAKER_00: What does a high school assistant principal need with a NASA setup like I have?
• 1:11
  SPEAKER_00: His is better than mine.
• 1:12
  SPEAKER_00: That's not it's not okay.
• 1:15
  SPEAKER_01: You need because when we're recording, podcast recording is serious business.
• 1:19
  SPEAKER_01: You need many, many screens.
• 1:21
  SPEAKER_01: It's basically like launching you know a SpaceX rocket.
• 1:24
  SPEAKER_01: That's basically what we're doing here.
• 1:26
  SPEAKER_00: I need a screen for everything.
• 1:28
  SPEAKER_00: Okay.
• 1:28
  SPEAKER_00: I need a screen for our script, I need a screen to look at you, and uh, that's the on the small screen, by the way.
• 1:34
  SPEAKER_00: That that is the truth.
• 1:36
  SPEAKER_00: And then I have another big screen to my right.
• 1:38
  SPEAKER_00: So the the script is on the left, you're right, dead center, and then I have our garage band and other things that we record with on the right.
• 1:46
  SPEAKER_00: And I like to you know levitate between all three, and I I just can't do that today.
• 1:51
  SPEAKER_00: So I'm a little bit off my little off.
• 1:53
  SPEAKER_01: So if uh if Chris is off his game, we know why.
• 1:56
  SPEAKER_01: Uh he's really struggling over there, and you know, we can all feel bad for Chris with only two screens.
• 2:01
  SPEAKER_00: So I thought he was my house is torn up right now.
• 2:04
  SPEAKER_00: My recording room is torn up.
• 2:05
  SPEAKER_01: I actually just thought of you, Chris, because just earlier this evening, we were over at one of my wife's colleagues' houses, and they have this unbelievable log cabin, which you would very much appreciate.
• 2:15
  SPEAKER_01: You live in a log cabin, and you would have appreciated this, but what I really thought you would appreciate is they have a little half bath on the main floor that their countertop is green river formation with fish fossils showing.
• 2:28
  SPEAKER_01: And it made me think of the time you and I were out there.
• 2:32
  SPEAKER_01: I don't know if we were in the green river formation or the white mountain formation, but we were we were splitting scale.
• 2:39
  SPEAKER_01: What's that?
• 2:39
  SPEAKER_01: Fluorescent.
• 2:40
  SPEAKER_01: The fluorescent.
• 2:41
  SPEAKER_01: And we were looking for insect fossils, and I found a little spider fossil.
• 2:45
  SPEAKER_00: I think I found a mosquito.
• 2:47
  SPEAKER_01: You found a mosquito.
• 2:48
  SPEAKER_01: It was so good.
• 2:49
  SPEAKER_01: An ant.
• 2:50
  SPEAKER_01: I think we both found a little ant or something like that.
• 2:52
  SPEAKER_01: It was so good.
• 2:53
  SPEAKER_01: That was really fun.
• 2:54
  SPEAKER_01: It wasn't Green River.
• 2:55
  SPEAKER_00: And that our little friend Brian didn't find anything, and he was very upset about that.
• 2:59
  SPEAKER_01: Yeah, that was a fun trip that we went on.
• 3:01
  SPEAKER_01: And that was the one time I well, you know this about me.
• 3:04
  SPEAKER_01: I'm not like naturally inclined to paleontology.
• 3:08
  SPEAKER_01: Like many fossils don't get me super excited.
• 3:10
  SPEAKER_01: I don't really know why, because they're really interesting, but I just don't get as excited.
• 3:14
  SPEAKER_01: Like, give me a big garnet any day over a trilobite fossil.
• 3:18
  SPEAKER_01: But this one was really fun, like finding spiders and ants and little mosquitoes.
• 3:22
  SPEAKER_01: That was actually kind of fun fossil collecting.
• 3:24
  SPEAKER_00: Well, I'm surprised.
• 3:25
  SPEAKER_00: A log cabin near the DC area, like that's not very common.
• 3:31
  SPEAKER_01: No, this is out in the woods in Pennsylvania, southeastern Pennsylvania.
• 3:34
  SPEAKER_01: Out in the woods, 10 acres, 12 acres, beautiful.
• 3:37
  SPEAKER_01: Nice.
• 3:37
  SPEAKER_01: So, Chris, today in uh what is this third, I guess, in the line of our sort of streams mini series that we got going on here, we're talking about levees, and this is one that you pitched.
• 3:50
  SPEAKER_01: So why don't you give us the pitch for levies here?
• 3:53
  SPEAKER_00: I don't know.
• 3:54
  SPEAKER_00: Levees are super important, first of all.
• 3:56
  SPEAKER_00: And I have spent a lot of time driving along levees, walking my dog along levees, because I, you know, I spend my time early April every year in Mississippi and Louisiana, and so that whole part of the Mississippi River is leveed, and they're it's enormous.
• 4:12
  SPEAKER_00: And so they have bike paths along the top of crushed limestone paths and all that kind of stuff, and dog parks along the levee.
• 4:19
  SPEAKER_00: It's just so I don't know.
• 4:20
  SPEAKER_00: I spent a lot of time there and it's it's an important topic.
• 4:23
  SPEAKER_01: You and I were together on a levee about a year and a bit ago at the AGU conference in Louisiana, in New Orleans, there, right?
• 4:30
  SPEAKER_01: We were walking around the levee there with the aquarium and having a coffee and maybe had a beer or something like that.
• 4:36
  SPEAKER_01: But yeah, so those of you that don't know, let's just define the levee right up front, right?
• 4:41
  SPEAKER_01: It is basically a barrier on the side of a stream.
• 4:45
  SPEAKER_01: And stream is a very general term in geology.
• 4:47
  SPEAKER_01: Stream is a sort of a river or a creek, anything of any size is stream, like flowing water is a stream and confined to a channel, yep.
• 4:55
  SPEAKER_01: Confined to a channel, and the levees are on the sides of the channel often.
• 4:58
  SPEAKER_01: And we're gonna discuss what these are, but they're kind of the embankments that that keep the water in the channel, more or less.
• 5:06
  SPEAKER_01: Is that accurate, Chris?
• 5:07
  SPEAKER_00: Absolutely.
• 5:08
  SPEAKER_00: And there are two kinds of levees there are natural levees and then there are artificial levees.
• 5:13
  SPEAKER_00: So let's talk about the natural levees first, and then we'll get into the artificial or man-made and why we do that and the pros and cons and all that.
• 5:21
  SPEAKER_00: That's kind of where we're gonna go today.
• 5:23
  SPEAKER_01: And let me interrupt you real quick there, Chris, and say we're gonna talk about sort of generally what they are, how they're constructed broadly, then the pros and geologically the cons of this, because it really relates to how streams function, and then we're gonna kind of point some future-looking discussion about like possible solutions or solutions that are being implemented out there in the real world to combat some of the cons that we're gonna discuss here.
• 5:47
  SPEAKER_01: So, like you said, lead us off.
• 5:49
  SPEAKER_01: Sorry for interrupting there, but natural and artificial two categories, what do we what do we got?
• 5:53
  SPEAKER_00: Let's talk about the natural levees first.
• 5:56
  SPEAKER_00: So, this is like an earthen embankment that parallels the channel, and it's right next to the river channel itself.
• 6:03
  SPEAKER_00: And so if you envision like a uh somewhat of a V-shaped, you know, channel shape to the stream, there will be a pile of sediment on each side of the river that parallels that that channel.
• 6:16
  SPEAKER_00: Okay, now I want to talk about why that happens.
• 6:18
  SPEAKER_00: So if this is hard because we have to like kind of paint a picture, so help me out with this, okay, Jesse.
• 6:23
  SPEAKER_00: But when a river rises, uh you have an event, okay?
• 6:27
  SPEAKER_00: A cloud burst, uh, you know, lots of snow melt, whatever, right?
• 6:30
  SPEAKER_00: We got we have an event where the river's swollen, it's really, really thick.
• 6:34
  SPEAKER_00: So it's about ready to spill out over its embankment.
• 6:39
  SPEAKER_00: So the river at this stage is moving fast.
• 6:43
  SPEAKER_01: So let me just think about this a minute.
• 6:45
  SPEAKER_01: If you're looking like kind of as a cross section of the stream, you have the little U-shaped thing where the water always is, that's the channel, and then this big flat thing on the side that we call the floodplain, where when it gets to flood stage, when the river breaks over its channel and is flooding, it's on this flat, broad plain that is on either side of the embankment.
• 7:02
  SPEAKER_01: That's we're kind of talking about here.
• 7:03
  SPEAKER_01: So sorry, go when it rises out and breaks out of its channel in flood stage, is where we're at.
• 7:08
  SPEAKER_00: Well, first, let me let me get everybody to the point where it's not quite flooded yet, but it's just about to.
• 7:13
  SPEAKER_00: So the river is really full, it's as full as it can be.
• 7:17
  SPEAKER_00: And in that situation, you have a high discharge.
• 7:19
  SPEAKER_00: You have a the stream is really ripping, right?
• 7:22
  SPEAKER_00: It's moving fast, so it's moving a lot of sediment, a lot of sand, a lot of gravel, and so on.
• 7:27
  SPEAKER_00: As soon as it rises up just a little bit more and it starts to spill out over the channel out onto the floodplain, it goes from being very deep to very, very shallow just at that one spot where it's on each side of the bank, it has just spilled out.
• 7:44
  SPEAKER_00: It's let's say it's an inch deep, right?
• 7:46
  SPEAKER_00: Well, the friction from that shallow water slows the river down right there, only there.
• 7:51
  SPEAKER_00: And whenever a river slows down, deposition is the rule.
• 7:55
  SPEAKER_00: So it deposits on each side of its own bank a little layer of sand and gravel.
• 8:00
  SPEAKER_00: Basically, that's the start of a levee.
• 8:02
  SPEAKER_00: Every time a river floods, it builds up this pile of sediment adjacent to the banks.
• 8:10
  SPEAKER_00: So it builds up its own levee system according to its own flood dynamics.
• 8:16
  SPEAKER_01: Yes, that's right.
• 8:17
  SPEAKER_01: So makes sense, yeah.
• 8:18
  SPEAKER_01: Yeah, absolutely.
• 8:19
  SPEAKER_01: So, like the frequency of flooding, the increase in river rate during the flood stage, so i.e., how much, how big of boulders can it transport downstream, how big of sediment can it transport downstream, and then what gets dumped off in the levee, like all those factor into the size that the levee will be relative to the size of the channel and the size of the floodplain and whether it's meandering and et cetera, et cetera.
• 8:40
  SPEAKER_01: So there's a lot of natural variables that go into the size of a natural levee on the banks, but I think you described that really well.
• 8:48
  SPEAKER_01: So if we go back to my sort of cross-section thing where we've got this U-shaped cutout, think of a broad, flat floodplain with a U-shaped cutout in the middle, that's where the river always is, the channel.
• 8:58
  SPEAKER_01: What you were describing is we got little bumps on the edge of the channel that go up above the floodplain.
• 9:04
  SPEAKER_01: These are the levees that are higher than the floodplain around it and right next to the channel, typically, or very close to the channel.
• 9:11
  SPEAKER_00: We often, you know, there are oftentimes roads and trails and so on adjacent to the levees, or right next to the levees, actually.
• 9:19
  SPEAKER_00: Those sometimes are maintained, right?
• 9:21
  SPEAKER_00: If you have a road, for instance, that is right adjacent to the levee, that road will be coated then in an event with sand and or gravel, and then they have to come off and they got to brush it aside or sometimes snow plow it off the road.
• 9:34
  SPEAKER_00: You know, I've seen this where I live along the Grand River.
• 9:37
  SPEAKER_00: Um, many times, especially in the spring when this thing floods over, that road is coated with six to eight inches of just really, really beautifully colored sand that then has to be moved off to the side.
• 9:49
  SPEAKER_00: So just look at rivers from now on and you'll look at them a little bit differently.
• 9:52
  SPEAKER_00: If it doesn't have a man-made artificial levee, they will have their own natural levee system of sand and or gravel adjacent to the river channel.
• 10:01
  SPEAKER_01: And that's a great segue, Chris, into artificial levees because we have a lot of artificial levees in the US and in the world, because most of the time those rivers are not at flood stage.
• 10:12
  SPEAKER_01: So we build our infrastructure, we build our civilization, often around rivers.
• 10:17
  SPEAKER_01: They're great places, they're beautiful, they're functional for a lot of reasons.
• 10:20
  SPEAKER_01: We build them around rivers, and most of the time it's not flood stage.
• 10:24
  SPEAKER_01: And so we build our stuff, usually near the flood zone or on the floodplain, right?
• 10:29
  SPEAKER_01: And then therefore, when it floods, we're like, oh crap, we don't want that.
• 10:32
  SPEAKER_01: So we build up the levee, take the natural levee and build it up bigger, or just make a new levee, and that's the artificial levee.
• 10:39
  SPEAKER_00: So basically, what you're saying is we have built some of our infrastructure on the floodplain of the river, and we can't we we just can't have that.
• 10:49
  SPEAKER_00: And so we, you know, we build it that we build up this earthen mound.
• 10:54
  SPEAKER_00: Most of the time it's just sand or dirt.
• 10:57
  SPEAKER_00: Okay.
• 10:58
  SPEAKER_00: Usually it's just like fill dirt.
• 10:59
  SPEAKER_00: Sometimes they're concrete.
• 11:01
  SPEAKER_00: Um, you know, various materials can be brought in to like kind of hem the river in, right?
• 11:06
  SPEAKER_00: That's what we're trying to do.
• 11:07
  SPEAKER_01: Yeah, so I mean, this is uh I kind of hearkened, it brought me back to our dams episode when we were talking about dams.
• 11:12
  SPEAKER_01: This sort of impressive statistics here.
• 11:14
  SPEAKER_00: That I Which by the way was another really good idea by me.
• 11:17
  SPEAKER_00: Okay, just saying that you know, in fact, it was such a good idea that we had to do two episodes on dams.
• 11:24
  SPEAKER_00: And we almost broke up on the first dam episode.
• 11:27
  SPEAKER_00: Oh man, you really pissed me off.
• 11:29
  SPEAKER_00: I'm I don't know if I ever were.
• 11:30
  SPEAKER_01: You're getting really pissed off of me again, aren't you?
• 11:32
  SPEAKER_01: Right now, just thinking about it.
• 11:36
  SPEAKER_01: Oh my goodness.
• 11:37
  SPEAKER_01: Well, anyway, so uh moral of the story, Chris is always right, and dams are pretty interesting.
• 11:42
  SPEAKER_01: So are levees.
• 11:43
  SPEAKER_01: Here's some stats for you, Chris.
• 11:44
  SPEAKER_01: So the U.S.
• 11:44
  SPEAKER_01: Army Corps of Engineers is generally responsible for many of these levees.
• 11:48
  SPEAKER_01: There are 6,890 levee systems in the U.S.
• 11:53
  SPEAKER_01: alone that the U.S.
• 11:54
  SPEAKER_01: Army Corps of Engineers is responsible for.
• 11:57
  SPEAKER_01: That's almost 25,000 miles of levee.
• 12:01
  SPEAKER_01: I mean, a ton of those are on the Mississippi River drainage system or the Missouri River.
• 12:05
  SPEAKER_01: You know, the big major rivers, they're they're heavily levied.
• 12:08
  SPEAKER_01: The average age, and this is really what made me think of our dams episode, the average age of the levees are 59 years old.
• 12:14
  SPEAKER_00: And the Which, by the way, is younger than me, but I'm gonna beat you to the punch.
• 12:18
  SPEAKER_01: Okay, I know you're gonna say something about that.
• 12:20
  SPEAKER_01: Okay.
• 12:21
  SPEAKER_01: So your average levy, if you're out there in the world, I said that wrong.
• 12:24
  SPEAKER_01: Damn it.
• 12:25
  SPEAKER_01: They're older than older than you.
• 12:27
  SPEAKER_01: Yes.
• 12:28
  SPEAKER_01: You give yourself more credit, Chris.
• 12:29
  SPEAKER_01: You're not that old yet.
• 12:31
  SPEAKER_01: Uh if you're out there and you see a levy, you can think, wow, that is really old.
• 12:35
  SPEAKER_01: It's even older than Chris Bullheis.
• 12:37
  SPEAKER_01: My God, it's super old.
• 12:39
  SPEAKER_01: The infrastructure bill that just passed in the US, the U.S.
• 12:41
  SPEAKER_01: Army Corps of Engineers estimates that 21 billion is needed to improve these things.
• 12:46
  SPEAKER_01: And that's only about 15% of the known levies in the U.S.
• 12:49
  SPEAKER_01: So, anyways, this is like a huge infrastructure um issue or topic and potential issue.
• 12:57
  SPEAKER_01: And it's one that doesn't get any credit.
• 12:59
  SPEAKER_01: You know what I mean?
• 13:00
  SPEAKER_01: Like it's one that we just don't think about until it becomes a really big problem.
• 13:04
  SPEAKER_01: And we're going to talk about some of those examples as we move through this.
• 13:07
  SPEAKER_00: The other thing that you left out of your stats there was that 97% of all levees are earthen embankments.
• 13:14
  SPEAKER_00: It's just it it that just basically means fill dirt brought in and just kind of stacked, you know, adjacent to the river on both sides.
• 13:22
  SPEAKER_00: Usually they're on both sides.
• 13:23
  SPEAKER_00: But that's the interesting thing, too, is that they're not always on both sides of the river, and they're not always equal heights, which present some problems that we're going to get into a little bit here in just the other thing.
• 13:32
  SPEAKER_01: The other thing, the other, you know, 3% are concrete, rock, steel, like all the things you'd kind of envision, like building stuff out of right.
• 13:38
  SPEAKER_01: So building materials of various kinds.
• 13:39
  SPEAKER_01: But earthen is the it dominates.
• 13:41
  SPEAKER_01: And that's a really interesting thing when we talk about well, we'll talk about the cons of of levees or some problems with them as we go through it.
• 13:48
  SPEAKER_01: But what are the pros?
• 13:48
  SPEAKER_01: Why do we build these things, Chris?
• 13:50
  SPEAKER_01: Like, let's start there, maybe.
• 13:51
  SPEAKER_00: Good call.
• 13:52
  SPEAKER_00: Why in the world do we build levees?
• 13:54
  SPEAKER_00: Because whenever you do something to a river, there are going to be consequences to that, which are going to be the cons, but they do serve a function.
• 14:01
  SPEAKER_00: I mean, number one, I think, is that they reduce flood frequency, they don't prevent floods.
• 14:06
  SPEAKER_00: There's a quote.
• 14:08
  SPEAKER_00: I don't know if I'm going to get this right, but I'm going to try.
• 14:10
  SPEAKER_00: There are two kinds of levies.
• 14:13
  SPEAKER_00: Those that have failed and those that are going to fail.
• 14:17
  SPEAKER_00: It's something along that line with levies.
• 14:19
  SPEAKER_00: I think a city planner made that quote along the Missouri or the Mississippi.
• 14:24
  SPEAKER_00: I can't recall.
• 14:24
  SPEAKER_00: But anyway, they reduce flood frequency.
• 14:27
  SPEAKER_00: They reduce how often the river's going to flood.
• 14:29
  SPEAKER_01: Yeah, and that's I think that's something that is maybe not intuitive.
• 14:32
  SPEAKER_01: We just need to explain just a little bit, is it's not, they don't really change the amount of water going through the river.
• 14:37
  SPEAKER_01: They change whether the river breaches its channel or not.
• 14:39
  SPEAKER_01: So you're just making the levee higher so that the river doesn't breach over the channel and make it and spill over into the floodplain and flood the floodplain.
• 14:48
  SPEAKER_01: So that's what we're talking about.
• 14:49
  SPEAKER_01: Like it doesn't change rainstorm events or the amount of water going through the channel at all.
• 14:53
  SPEAKER_01: It just constrains it.
• 14:54
  SPEAKER_01: So that's what you mean by that.
• 14:55
  SPEAKER_00: It just allows the river to build higher and higher before it floods out over its embankment.
• 15:00
  SPEAKER_00: The other thing is, too, that goes kind of along with the meandering river episode we had a while back, is that it keeps shipping lanes consistent, right?
• 15:09
  SPEAKER_00: We can't just have river changing and eroding, you know, the cut bank and point bar dynamic that streams have and just doing its own thing.
• 15:17
  SPEAKER_00: We were kind of trying to hem the river in and keep the shipping lanes and roads and so on consistent.
• 15:23
  SPEAKER_01: And then the other thing that they provide is they stop or slow the erosion along the banks, along the stream banks.
• 15:30
  SPEAKER_01: And all of these things kind of factor together.
• 15:32
  SPEAKER_01: So reducing flood frequency, keeping consistent shipping lanes, and slowing or stopping the erosion along the stream banks, really what we're doing is we're protecting our societal infrastructure.
• 15:42
  SPEAKER_01: That's kind of the goal here.
• 15:44
  SPEAKER_01: And there's a couple And why is that important?
• 15:46
  SPEAKER_00: Go ahead, Jesse, and say why that's important then.
• 15:49
  SPEAKER_01: Because you have some interesting stats here that kind of back this up, like the necessity of again, these sort of uh Chris, this was a fun episode to put together because it's sort of mind-blowing statistics.
• 16:00
  SPEAKER_01: 17 million people in the US alone live or work behind a levy.
• 16:04
  SPEAKER_01: That blew me away.
• 16:05
  SPEAKER_01: I I would have never guessed it was that much.
• 16:08
  SPEAKER_01: Meaning they live or work in a floodplain that is protected by a levee.
• 16:12
  SPEAKER_01: That's what that actually means, right?
• 16:14
  SPEAKER_01: So behind a levy, you're you're in an area that would flood frequently were it not for the levy right next door.
• 16:21
  SPEAKER_01: They protect$2.3 trillion of property, 4,500 schools with over 2 million students in them, and like, you know, obviously a ton of industry and city centers, and some of the famous ones that we have heard about recently.
• 16:33
  SPEAKER_01: New Orleans is a great example of a levy system that failed with catastrophic results.
• 16:37
  SPEAKER_01: So there's a lot of pros to levees, right?
• 16:40
  SPEAKER_01: We sort of, for historical and modern reasons, build our infrastructure around rivers that are meandering.
• 16:46
  SPEAKER_01: They're big rivers, big shipping lanes, all this stuff, and they are protecting that infrastructure.
• 16:51
  SPEAKER_01: So there are good, valid reasons to build levees.
• 16:54
  SPEAKER_00: So I have a thought, okay, because I do an exercise with my upper level smart kid geology students, right?
• 17:02
  SPEAKER_00: And I give them the situation.
• 17:04
  SPEAKER_00: I give them a situation where I have a meandering river.
• 17:07
  SPEAKER_00: Let's say it's maybe 20, 25 miles of river section, and you have two towns.
• 17:12
  SPEAKER_00: One is on the upstream side of this river, and one is on the downstream side.
• 17:16
  SPEAKER_00: And the upstream city floods all the time.
• 17:19
  SPEAKER_00: The downstream city does not.
• 17:21
  SPEAKER_00: And the problem I give them is all right, we'll solve the problem.
• 17:25
  SPEAKER_00: I draw it on the board, I show them where the cities are, show them the position of the meandering river, solve the problem.
• 17:31
  SPEAKER_00: And I just give them a few rules.
• 17:32
  SPEAKER_00: Obviously, you can't move the towns, and you, you know, you have to deal with the situation as is.
• 17:37
  SPEAKER_00: And what can you do, right?
• 17:38
  SPEAKER_00: Your your solution is I can build dams, I can maybe rechannel the river, reroute the river, right?
• 17:46
  SPEAKER_00: And I can levy the river.
• 17:48
  SPEAKER_00: And they have to support their reasoning with all right, well, everything that you do is gonna have consequences, whether it's building a dam, and we talked about that a long time ago and so on, the consequence of doing this.
• 17:58
  SPEAKER_00: So almost always my students choose to levy the river.
• 18:04
  SPEAKER_00: That parallels what engineers do.
• 18:07
  SPEAKER_00: You know, I mean, that's been our solution to dealing with rivers that flood.
• 18:13
  SPEAKER_00: We just like to levy them.
• 18:15
  SPEAKER_00: So that offers then a good segue into well, all right, we painted a good picture of why we do that and the pros to it, which are they're not to be neglected.
• 18:23
  SPEAKER_00: These are these are upsides.
• 18:25
  SPEAKER_00: What are the cons?
• 18:26
  SPEAKER_00: What are the downsides to levying a river?
• 18:28
  SPEAKER_00: Because there are consequences.
• 18:30
  SPEAKER_01: I think the first con here, Chris, is a bit of a counterintuitive one, perhaps, is that often levies will increase flooding upstream from the levees.
• 18:38
  SPEAKER_01: So although it protects flooding downstream, it creates more flooding upstream.
• 18:43
  SPEAKER_01: Why?
• 18:43
  SPEAKER_00: Let's think about that.
• 18:44
  SPEAKER_00: Is that counterintuitive?
• 18:46
  SPEAKER_00: Because to my students, it is.
• 19:04
  SPEAKER_01: Why does that happen?
• 19:05
  SPEAKER_01: What do you say to your students, Chris, when they're like, eh, Mr.
• 19:07
  SPEAKER_01: Boyce, what I don't get it?
• 19:09
  SPEAKER_01: What's going on?
• 19:10
  SPEAKER_01: Why, why is this not why is it working this way?
• 19:12
  SPEAKER_00: I think I have a good analogy for it.
• 19:14
  SPEAKER_00: I always say, well, it's a traffic jam.
• 19:17
  SPEAKER_00: When you go from five lanes of freeway down to one, then you get backed up, right?
• 19:23
  SPEAKER_00: Isn't that what happens when you levy a river?
• 19:26
  SPEAKER_00: And they're still, though, they're like, Well, uh, why?
• 19:29
  SPEAKER_00: Well, if you didn't have the levies there, what would the river do?
• 19:33
  SPEAKER_00: Right?
• 19:34
  SPEAKER_00: The river would just spill out over its banks, flood the floodplain.
• 19:38
  SPEAKER_00: You know, let's think about that a second.
• 19:40
  SPEAKER_00: Let's let that soak in, the floodplain.
• 19:43
  SPEAKER_00: Okay.
• 19:44
  SPEAKER_00: And you're distributing this massive amount of water then over a broad area, but not when you levy the river.
• 19:51
  SPEAKER_00: Now you're confining it in, you're pinching it into this narrow channel, and you're causing the water then to kind of back up, much like a traffic jam on a busy freeway during rush hour.
• 20:04
  SPEAKER_01: Yeah, and I think it's really important to consider and remember that all of these streams have this branching upstream network, right?
• 20:10
  SPEAKER_01: So as you go upstream, the streams get smaller and smaller, but they're all connected, they're all interconnected.
• 20:14
  SPEAKER_01: And this is a really important concept that although the the river is flowing downstream, all the water, you know, any individual water particle, we talked about in the streams episode how you can only step in one river once and then it's gone.
• 20:26
  SPEAKER_01: It's not the same river anymore.
• 20:28
  SPEAKER_01: All that applies, but the physics of how the water moves through the system are it's like a house plumbing system, right?
• 20:34
  SPEAKER_01: Like if you clog up one side of it, it affects the other parts of the house plumbing system.
• 20:38
  SPEAKER_01: It's got they're all this kind of interconnected pathway.
• 20:40
  SPEAKER_01: So I like the traffic jam analogy, Chris, that you put some construction.
• 20:44
  SPEAKER_01: It's construction season here in Pennsylvania.
• 20:46
  SPEAKER_01: So there's construction all over the place.
• 20:48
  SPEAKER_01: And uh yeah, there's always traffic backups when there's you know a few people working on one side of the highway that close down one tiny little bit of lane for a half a mile and it's backed up for miles and miles and miles on the backside.
• 20:59
  SPEAKER_01: So good analogy.
• 21:01
  SPEAKER_00: I've driven so many times, countless times, down the floodplain of the Mississippi River.
• 21:07
  SPEAKER_00: And that floodplain can be five or six miles wide on one side alone, not to speak of the other side as well.
• 21:14
  SPEAKER_00: So think about that a second.
• 21:15
  SPEAKER_00: Five or six miles wide on one side, that's a lot of water that can be distributed and spread out over that broad flat plain that now you're confining into the channel, so it's gonna back it up.
• 21:26
  SPEAKER_01: That brings up a really interesting point because this sort of dual side to the river, we talked about streamyanders and how you know one side is cutting faster.
• 21:33
  SPEAKER_01: And another important point that we talked about is how when a river comes out of a bend, the water is directed not straight down the river anymore, but kind of to the other side of the bank.
• 21:45
  SPEAKER_01: So it's if if it's a left turn hand turn, so if the river is turning from the left side and bending back to the right, the river is going to be directed to the right side of the river and gonna hit the right side embankment on the next turn.
• 21:57
  SPEAKER_01: And this brings up an interesting point.
• 22:00
  SPEAKER_01: That not all levees, you made it earlier, not all levees are the same height on either side of the river.
• 22:05
  SPEAKER_01: And that affects the river current.
• 22:06
  SPEAKER_01: And especially in places like where there's perhaps a state boundary on one side of the river and another state on another side of the river in two different jurisdictions, you know, they could get into fights about the size of the levee and who's directing water to which side of the river and who's doing more damage.
• 22:23
  SPEAKER_01: I mean, it reminds me of of um it reminds me of like wave breaks along the beach where you know if somebody puts a big uh concrete barrier up, it directs all the wave energy to their neighbors and their neighbors get a lot more erosion.
• 22:35
  SPEAKER_01: It's kind of the same debate here on either side of the river.
• 22:38
  SPEAKER_00: It is very similar to that for sure, for sure.
• 22:41
  SPEAKER_00: So that's one serious downside is flooding upstream from when the levees begin, right?
• 22:46
  SPEAKER_00: But there are others, and let's get into those a little bit.
• 22:49
  SPEAKER_00: The other one is that let's think about what the concept of a floodplain is, right?
• 22:54
  SPEAKER_00: It's a broad flat plain that is meant to flood.
• 22:58
  SPEAKER_00: And so what levees do is they disconnect the river from its own floodplain.
• 23:04
  SPEAKER_00: So, in other words, in in geology, and like fluvial geomorphologists is a really annoying and fancy term for just a river guy.
• 23:11
  SPEAKER_00: You know, let's say our good friend Andy is a flu.
• 23:14
  SPEAKER_01: He likes to say I'm a fluvial geomorphologist, Andy Andy likes to put his pinky in the air while he's having a beer and call himself a fluvial geomorphologist.
• 23:22
  SPEAKER_01: Yeah.
• 23:23
  SPEAKER_00: But they like to say that these levees, then, if you don't allow the river to flood, and you know, when a river's flooding like this, we already established that it's ripping, it's moving really fast, right?
• 23:34
  SPEAKER_00: So it's carrying a lot of sediment.
• 23:36
  SPEAKER_00: When it floods, it spreads that sediment out over the floodplain, and they call it the gift of the river, which is a really appropriate term because it is.
• 23:44
  SPEAKER_00: It's very, very fertile soil, then that's being distributed out across the floodplain.
• 23:50
  SPEAKER_00: So agriculture is a great use for floodplain.
• 23:54
  SPEAKER_01: It's why it's such good cropland.
• 23:56
  SPEAKER_01: It's why we were talking to Andrew Alden, he brought up that the Grand River used to flow through Hudsonville, Michigan.
• 24:01
  SPEAKER_01: And that's why it's such great farmland there is because you know it was sitting on the floodplain of the ancient Grand River, the glacial Grand River system.
• 24:09
  SPEAKER_01: And so we're gonna come back to this point, this gift of the river point.
• 24:12
  SPEAKER_01: So let's like store that in our memory banks because we're gonna come back to the point where we talk about solutions here.
• 24:17
  SPEAKER_01: Yeah.
• 24:17
  SPEAKER_00: So, Jesse, before you go on to that, I know where you're going because I know your little mind there.
• 24:22
  SPEAKER_00: Um, I also want to talk about another con, which I think is a serious con.
• 24:26
  SPEAKER_00: When rivers flood and it's spread out way out over this broad flat floodplain, you're allowing water then to seep in and then recharge the water table below.
• 24:36
  SPEAKER_00: So we're allowing, we're talking about groundwater recharge by flooding rivers.
• 24:40
  SPEAKER_00: What you don't get that when you're not allowing the river to flood.
• 24:44
  SPEAKER_00: We're just getting it through this channel and bringing it downstream and eventually to the oceans because that's the ultimate destination of rivers.
• 24:52
  SPEAKER_00: So groundwater recharge.
• 24:54
  SPEAKER_01: Let me make a point on that because I think when you picture, at least when I picture a levee or when I picture a stream, you know, I'm usually picturing something relatively small with a floodplain that's not that big.
• 25:06
  SPEAKER_01: But really, you know, what we're kind of talking about here is picture the Mississippi River with five miles of floodplain on one side and five miles on the other.
• 25:14
  SPEAKER_01: That's the scale of groundwater recharge that we're kind of talking about, where this is super, super duper important.
• 25:19
  SPEAKER_01: And you're not just flushing all that water downstream as fast as possible with the levees funneling it down, but you let it seep out and percolate in as it spreads out over 10 horizontal miles from the river.
• 25:32
  SPEAKER_01: That's that's a massive amount of recharge.
• 25:34
  SPEAKER_01: So, two last cons here, I think.
• 25:37
  SPEAKER_01: Well, three really, and and the third one kind of leads into our solutions here.
• 25:41
  SPEAKER_01: But I don't know if this is counterintuitive or not, but actually the duration of flood events is increased with levees because it's harder for the water to get back into the channel and therefore out of the region.
• 25:54
  SPEAKER_01: And I think that kind of holds.
• 25:55
  SPEAKER_00: Hold on, I gotta interrupt you a second.
• 25:57
  SPEAKER_00: That is because all levees will either flood, the river will rise above the levee that you built, or they will fail.
• 26:05
  SPEAKER_00: And then because a levee keeps the water hemmed in, it's also gonna keep it hemmed out, right?
• 26:10
  SPEAKER_00: It's not gonna let it back in.
• 26:12
  SPEAKER_00: Is that what you're saying?
• 26:13
  SPEAKER_01: Yeah, so you you once the water breaks through the levee, it won't get back into the channel and it'll kind of prolong the flooding event longer than it that it naturally would have been, let's say.
• 26:23
  SPEAKER_01: And the other point here, and then Chris, you can lead us into the solutions here.
• 26:27
  SPEAKER_01: Though the last point is an interesting one, and it kind of we talked about this with dams, is that when you levy the river, the river breaks out into its floodplain and then can't get back in.
• 26:37
  SPEAKER_01: And what is it, what's another there's another effect here though.
• 26:40
  SPEAKER_01: There's another sort of long-term stream evolution effect.
• 26:44
  SPEAKER_01: I don't know, Chris.
• 26:45
  SPEAKER_01: I don't know how to explain it.
• 26:46
  SPEAKER_00: Well, I'm sorry, but the teacher side comes out of me on this because I want to ask the question to our listeners like, what do you think another consequence could be, right?
• 26:54
  SPEAKER_00: Because you're talking about river that would be at flood stage, so it's ripping, it's moving, it's fast, and it's moving a ton of sediment down slope, right?
• 27:03
  SPEAKER_00: But we're not allowing it to flood.
• 27:04
  SPEAKER_00: So we're depriving the floodplain of its gift.
• 27:08
  SPEAKER_00: So where does all the sediment go?
• 27:10
  SPEAKER_00: What's the consequence of not allowing that sediment to be spread out over the floodplain?
• 27:16
  SPEAKER_00: So, my young sage, I'm gonna let you handle the answer to that question, but I did want to pose it.
• 27:21
  SPEAKER_01: Well, there's two, I think there's two ways I would uh at least my mind goes to answering this question.
• 27:27
  SPEAKER_01: The first is okay, there's not sediment being deposited in the floodplain.
• 27:31
  SPEAKER_01: So maybe the floodplain is subsiding, which it is.
• 27:34
  SPEAKER_01: Like if you're not adding sediment to the floodplain, the floodplain subsides and kind of sinks down a little bit.
• 27:40
  SPEAKER_01: The other thing is that you have more sediment in the river channel.
• 27:43
  SPEAKER_01: So the river channel goes up, like sediment is deposited in the bed of the river, and the actually the bed level of the river raises up.
• 27:50
  SPEAKER_01: And so you have this kind of duality thing, this kind of teeter-totter going on where the floodplain is sinking and the river channel is raising, which means to keep the river within the channel, we need to build our levees higher, which means the river channel gets higher and higher, and we need to keep building our levees higher.
• 28:06
  SPEAKER_01: And then you have this thing where you get in New Orleans is a big problem, where you have this inversion where the river channel is actually higher than the floodplain outside of the levee, which creates, as we've seen, catastrophe at times.
• 28:17
  SPEAKER_01: Because Chris, yeah, I want to let that sink in.
• 28:20
  SPEAKER_00: You just said that the bottom of the river is higher than its own floodplain because of the situation, and that's a really powerful thing to let sink in a second.
• 28:32
  SPEAKER_00: That's a problem, you know.
• 28:34
  SPEAKER_01: You can see why it would be a big problem, right?
• 28:37
  SPEAKER_01: You know, we've seen this happen catastrophically recently in the US and elsewhere.
• 28:42
  SPEAKER_01: And this is the last con, is that large floods break levees.
• 28:47
  SPEAKER_01: In 2019, this was a really recent example, right?
• 28:49
  SPEAKER_01: The Missouri River flooded.
• 28:51
  SPEAKER_01: It didn't actually rain that much at the site of the flooding.
• 28:54
  SPEAKER_01: All the rain happened upstream, up in Minnesota and way up in the upper reaches, but massive amounts of rain in these small tributary streams, they all get aggregated together.
• 29:03
  SPEAKER_01: In 2019, the Missouri River breached a hundred levees, inundated 1.2 million acres of flooding, and damaged a ton of infrastructure.
• 29:14
  SPEAKER_01: One of the levee systems was breached in seven locations in one sort of levee system along the way.
• 29:21
  SPEAKER_01: And I think this leads us nicely into some potential solutions because I think the solutions are almost as interesting as you know the problem itself.
• 29:30
  SPEAKER_01: There's some really interesting geoscience in these solutions, right?
• 29:34
  SPEAKER_01: So, Chris, I mean, we could spend a long time talking about these solutions.
• 29:37
  SPEAKER_01: I I'm sure you did a deep dive and gotten some rabbit holes with these solutions.
• 29:41
  SPEAKER_01: I kind of did the same thing and uh picked out a few that were kind of interesting.
• 29:44
  SPEAKER_01: But I don't know what what struck you about some of these uh solutions?
• 29:48
  SPEAKER_00: Well, I think the one that is the most appealing makes sense to talk about first, at least for me anyway, and that's the idea of setback levies, where you take them and and you kind of like well, you do exactly what it sounds like.
• 30:01
  SPEAKER_00: You set the levee back a bit from the river, and you're allowing it then to flood out a little bit anyway.
• 30:09
  SPEAKER_00: It depends upon you know what you have to work with, right?
• 30:12
  SPEAKER_00: But you're allowing it to flood out onto the floodplain, seep down in, you're kind of spreading that out, you're widening the channel and giving it a chance to do its thing.
• 30:22
  SPEAKER_00: So that's an appealing alternative.
• 30:24
  SPEAKER_00: I you know, I don't know it's not always feasible, right?
• 30:28
  SPEAKER_00: Because if you have infrastructure that does not allow that, I mean you'd either have to relocate the infrastructure, which that's always our last alternative, or our last, like, okay, let's do that.
• 30:37
  SPEAKER_00: That's just not a viable solution in some cases.
• 30:40
  SPEAKER_01: And I I think there's a good example of this.
• 30:42
  SPEAKER_01: It was finished in 2021 along the Missouri River, part of this reach that flooded in 2019, where you know there's been a setback where the the levee system is being set back along one section of the river and it's reconnecting a thousand acres of floodplain.
• 30:57
  SPEAKER_01: This is an issue that is is not without controversy because you have to go and you have to say, hey, person who owns the farm here that's behind a levee, oh, tomorrow you're not gonna be behind the levee anymore.
• 31:08
  SPEAKER_01: You're gonna be in the floodplain.
• 31:09
  SPEAKER_01: Like you can see how that's a problem and a potentially contentious issue, right?
• 31:13
  SPEAKER_01: This particular instance, there was a lot of state forest and um federal land that was part of that.
• 31:18
  SPEAKER_01: So it's a little bit easier, but it's a pretty good test of how well do these work on large river systems that are prone to flooding, like the Missouri River system.
• 31:26
  SPEAKER_01: And so I think there's gonna be some exciting data that comes out of some of these tests.
• 31:31
  SPEAKER_01: I think for me, Chris, one interesting aspect was the idea of notching levees.
• 31:35
  SPEAKER_01: And so, you know, if you think about So are you talking about spillways then?
• 31:39
  SPEAKER_00: Is that what you're saying?
• 31:40
  SPEAKER_00: Yeah, yeah.
• 31:41
  SPEAKER_01: Like cutting, and you know, we're picturing and we've we've been describing levees as like a continuous hill of sediment along the river channel.
• 31:48
  SPEAKER_01: And instead of just having a continuous hill, you just kind of make a notch somewhere so that when the flood happens, it can kind of get out and you can control how much it gets out.
• 32:00
  SPEAKER_01: And so you can kind of control quote unquote the flooding in a way and allow the river to replenish the floodplain sort of as much as you want at that particular time.
• 32:10
  SPEAKER_01: So maybe when it's not uh high crop season and a flood happens, you can let it out and replenish the river.
• 32:15
  SPEAKER_01: And if it it is gonna flood during crop season where you really can't afford that, then you don't let it flood through the notch.
• 32:21
  SPEAKER_01: And so we can kind of tune the levy system a little bit to our desires, which it seemed interesting to me for certain scenarios at least.
• 32:29
  SPEAKER_00: I've seen these firsthand actually along the Ohio River.
• 32:32
  SPEAKER_00: Oh, yeah.
• 32:32
  SPEAKER_00: Um, so my son and I have gone to Cincinnati Bengals games.
• 32:36
  SPEAKER_00: Oh yeah, totally.
• 32:37
  SPEAKER_00: We we've gone to a game every year since he was like four years old.
• 32:41
  SPEAKER_00: And walking along the Ohio River there on the Kentucky side, that's usually where I have seen the um the notches that are cut in it.
• 32:49
  SPEAKER_00: And it is it's so obvious.
• 32:51
  SPEAKER_00: You know, you have this huge levee, it's enormous.
• 32:53
  SPEAKER_00: And then there are these slats cut in it, and they put these like steel, flat steel sheets across the slat so that if they want to let the water out or let the water into the river, whatever's going on, they have these notches where they can remove the the slats, and therefore you have a notch in the nut levee system.
• 33:13
  SPEAKER_00: It's really kind of a cool idea.
• 33:14
  SPEAKER_01: I I like that idea.
• 33:16
  SPEAKER_01: That that had some appeal to me.
• 33:17
  SPEAKER_01: Um, you sent a link, Chris, and we'll put this in the show notes.
• 33:21
  SPEAKER_01: If you want to see some amazing graphics about levees as we kind of wrap up here, where levees get placed, how they protect streams.
• 33:29
  SPEAKER_01: There's uh an article about Mount Carmel, Illinois that it really shows some really cool graphics on the border of Illinois and Indiana, where the Wabash River is being levied and sort of potential outcomes here in the differences in peak water flows with levees and without levees.
• 33:45
  SPEAKER_01: Like there's some really interesting geoscience in here that kind of shows some of the potential solutions that people are testing out.
• 33:52
  SPEAKER_01: So I just I don't know, Chris.
• 33:54
  SPEAKER_01: This shocked me, this astonished me.
• 33:55
  SPEAKER_01: Levees are so important, very underappreciated for our society, and we need to learn more about levees.
• 34:02
  SPEAKER_01: And there's some really interesting tests going on as we speak about compromises between the natural river system and a river with infrastructure around it that we really can't afford to have flooding all the time.
• 34:14
  SPEAKER_00: So yeah, that's right.
• 34:15
  SPEAKER_00: It's interesting that you say you know that that levies are kind of like not appreciated and kind of undervalued or not really thought of a lot.
• 34:24
  SPEAKER_00: And that's interesting because it's our go-to.
• 34:26
  SPEAKER_00: That's how we deal with rivers more often than not.
• 34:29
  SPEAKER_00: That's what we do is we levy the river.
• 34:31
  SPEAKER_01: So Chris, but it's like everything in geoscience.
• 34:34
  SPEAKER_01: We're just so undervalued, we're underappreciated.
• 34:36
  SPEAKER_01: I mean, I don't get paid enough, you don't get paid enough, we're not appreciated, we're not celebrated when we walk down the highway, people aren't throwing us parades.
• 34:45
  SPEAKER_01: Like, what's up with that?
• 34:46
  SPEAKER_01: I mean, we really should be getting a lot.
• 34:48
  SPEAKER_00: We're trying to change that one person at a time, Jesse.
• 34:51
  SPEAKER_00: Hey.
• 34:52
  SPEAKER_00: But I know you don't like it when I pitch an idea on the show, but I'm gonna pitch an idea for a future episode here.
• 34:57
  SPEAKER_00: It was like, especially, Chris.
• 34:59
  SPEAKER_01: The reason I don't like it is because you always say, Jesse, I'm always right.
• 35:02
  SPEAKER_01: Just say you trust me.
• 35:04
  SPEAKER_00: Well, just trust me, Jesse.
• 35:05
  SPEAKER_00: Just trust me.
• 35:06
  SPEAKER_00: Just trust me here.
• 35:07
  SPEAKER_00: Just trust me.
• 35:08
  SPEAKER_00: We need to do an episode on the human impact of flooding.
• 35:11
  SPEAKER_00: You know, we touched on it here that the Mississippi and the Missouri have had numerous hundred-year floods in the last decade, right?
• 35:18
  SPEAKER_00: And sure, climate change plays a role in this, but but so do we.
• 35:22
  SPEAKER_00: Uh not in the way of climate change, but in the things that we build have played a role in how often rivers flood, their recurrence intervals.
• 35:31
  SPEAKER_00: You know what I think we should do.
• 35:32
  SPEAKER_01: Yeah, to you know what I think we should do for that?
• 35:34
  SPEAKER_01: We should we should go interview a state hydrogeologist who thinks about this for a particular area and you know models what a hundred-year, a thousand-year flood will look like.
• 35:43
  SPEAKER_01: I think that'd be a really interesting conversation with somebody who's sort of an expert at modeling these types of things because I think some of the things that they they do is really, really impressive and and frankly a little bit beyond me because it gets complicated trying to think about these things.
• 35:59
  SPEAKER_01: But I agree with you.
• 35:59
  SPEAKER_01: I think that's a super interesting point and something that's underappreciated and shows the sort of breadth that geoscience uh matters a lot.
• 36:08
  SPEAKER_00: We we are really good friends with a fluvial geomorphologist, but you know, I think you're right.
• 36:14
  SPEAKER_00: We should hire a true expert to come on this zone.
• 36:17
  SPEAKER_01: We don't want to mess around with fluvial geomorphologists.
• 36:20
  SPEAKER_01: Oh my goodness.
• 36:23
  SPEAKER_01: Oh goodness.
• 36:25
  SPEAKER_01: Hey, that's I think that's a wrap for Levi's Chris.
• 36:27
  SPEAKER_01: This is super interesting, good episode.
• 36:29
  SPEAKER_01: Gosh, you're okay.
• 36:31
  SPEAKER_01: Every once in a while you come up with some good idea.
• 36:35
  SPEAKER_01: You're one for one.
• 36:37
  SPEAKER_01: Just crushing it over there, just crushing it.
• 36:39
  SPEAKER_01: Hey, if you want to learn all the basics of geoscience with audio discussions with us and all the images you need in a mobile online platform, go to campgeo geo.campcourses.com.
• 36:50
  SPEAKER_01: It's the first link in your show notes.
• 36:52
  SPEAKER_01: That's Chris and I have produced basically all the content that we teach in our intro to geology classes at the college level or the high school AP level, basically.
• 37:02
  SPEAKER_01: First link in your show notes, go there, check it out, let us know what you think.
• 37:05
  SPEAKER_01: You can go to our website, planetgeocast.com.
• 37:07
  SPEAKER_01: There you can subscribe, support us.
• 37:09
  SPEAKER_01: We always appreciate that, and find our own episodes.
• 37:12
  SPEAKER_01: And if you're on a podcast platform, just leave us a rating and a review.
• 37:16
  SPEAKER_01: We really appreciate it.
• 37:17
  SPEAKER_01: Cheers.
• 37:18
  SPEAKER_01: Peace.