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Dammed if We Do, Dammed if We Don't! · PlanetGeo: The Geology Podcast

• 0:03
  SPEAKER_00: Welcome to Planet Geo, the podcast where we talk about our amazing planet, how it works, and why it matters to you.
• 0:12
  SPEAKER_00: Chris, how you doing today?
• 0:14
  SPEAKER_00: I'm doing great.
• 0:14
  SPEAKER_00: How are you doing, Jesse?
• 0:16
  SPEAKER_00: Oh man, I'm doing really well.
• 0:17
  SPEAKER_00: I'm excited for today's episode, to be honest with you.
• 0:19
  SPEAKER_00: But before we get to that, let's do some brief introductions.
• 0:22
  SPEAKER_00: You are Chris Bullheis, a nationally recognized Earth Science teacher from the great state of Michigan.
• 0:27
  SPEAKER_01: And you are Jesse Remink, one of my former students, now a professor of geoscience at Penn State.
• 0:33
  SPEAKER_00: And this is Planet Geo, a podcast where we talk about amazing aspects of our planet and why it matters to our everyday lives.
• 0:40
  SPEAKER_00: Hey, before we get into it too much, we would just ask one thing.
• 0:44
  SPEAKER_00: If you're listening to this podcast and you like it, you get something out of it, you learn something, please share it with somebody, even just one person you know.
• 0:52
  SPEAKER_00: We really love doing this.
• 0:53
  SPEAKER_00: We obviously really love the geosciences, but it takes a bit of effort, and we'd love it if you shared it with someone you know who might appreciate it as well.
• 1:01
  SPEAKER_00: Right on.
• 1:02
  SPEAKER_00: You bet.
• 1:03
  SPEAKER_00: So with that, let's uh let's get into it.
• 1:06
  SPEAKER_00: Chris, what are we talking about today?
• 1:08
  SPEAKER_01: Well, today we're gonna talk about dams.
• 1:10
  SPEAKER_01: And I this is uh to me, I can't wait.
• 1:13
  SPEAKER_01: This is um something that is close to home for for both you and I, you know.
• 1:17
  SPEAKER_01: Um, but it this is close to home for a lot of people.
• 1:20
  SPEAKER_01: Um, so we're gonna get into why do we build dams?
• 1:23
  SPEAKER_01: How many dams are there in the United States and things like this?
• 1:28
  SPEAKER_00: So um yeah, absolutely.
• 1:30
  SPEAKER_00: I mean, I I I must say I was a little bit maybe on the fence about this topic to start out, but once we started diving into it, you totally convinced me.
• 1:37
  SPEAKER_00: I um I went, you know, we we both went on deep dives about dams and learned a lot, and they're really important and fun and important for the geosciences.
• 1:44
  SPEAKER_00: So, right, where are we gonna go this episode?
• 1:47
  SPEAKER_01: We're gonna get into some statistics about dams in the United States.
• 1:52
  SPEAKER_01: Then we're gonna talk about a special dam in the in Rocky Mountain National Park called the Lawn Lake Dam and what happened to that.
• 1:59
  SPEAKER_01: And then we're gonna get into just some of the things about why we build dams in the first place.
• 2:05
  SPEAKER_01: And then, of course, it's a geology podcast.
• 2:07
  SPEAKER_01: We've got to talk a little bit about the geology of dams.
• 2:10
  SPEAKER_01: And then finally, just kind of tying that into another issue that happened here in Michigan with the Eden Lake Dam.
• 2:17
  SPEAKER_00: Yeah, which was a big deal, like right after the COVID lockdowns or right down during the height of the COVID lockdowns, I suppose.
• 2:23
  SPEAKER_01: So very recent.
• 2:24
  SPEAKER_00: Yeah, so let's get into it.
• 2:26
  SPEAKER_00: I mean, why do we build dams?
• 2:29
  SPEAKER_00: Dams, we all kind of know what dams are in a rough sense, but why do we build them as humans?
• 2:33
  SPEAKER_01: Well, you know, a lot of reasons, I think.
• 2:35
  SPEAKER_01: You know, it's interesting when you look into this.
• 2:38
  SPEAKER_01: Uh, you get hydroelectric dams, right?
• 2:40
  SPEAKER_01: And um that that's a that can be a reason, but the number one reason why dams are built in the United States anyway is recreation.
• 2:49
  SPEAKER_01: You get this big you get this big lake behind it, and it's it's you know, it's it this reservoir that's created behind a dam is a great place to to ski and fish and just recreate.
• 3:01
  SPEAKER_01: So that's the number one reason.
• 3:02
  SPEAKER_00: Absolutely.
• 3:03
  SPEAKER_00: And it goes back, you know, quite a ways.
• 3:05
  SPEAKER_00: I mean, we've been as humans, we've been building dams for around 5,000 years.
• 3:09
  SPEAKER_00: The first recorded dam was built in ancient Mesopotamia.
• 3:12
  SPEAKER_00: There's several built by ancient human civilizations.
• 3:15
  SPEAKER_00: The Romans were like amazing builders of dams.
• 3:18
  SPEAKER_00: They also built aqueducts, which they're probably more famous for, but some of their dams were like 160 feet high and they lasted till the present.
• 3:25
  SPEAKER_00: Some of them kind of still function in some way.
• 3:27
  SPEAKER_00: It's amazing.
• 3:28
  SPEAKER_01: It is amazing.
• 3:29
  SPEAKER_01: I think they're an engineering feat, to be honest with you.
• 3:31
  SPEAKER_01: They're they're curious to me from that standpoint alone.
• 3:35
  SPEAKER_01: You talk about how dams have been built for 5,000 years by humans, beaver's been doing it for a long time.
• 3:40
  SPEAKER_00: That's right, that's right.
• 3:41
  SPEAKER_00: Those little industrious little creatures, man, they just go crazy.
• 3:45
  SPEAKER_00: They do.
• 3:47
  SPEAKER_00: So we build dams for recreation, we build dams to control flooding as well, and we also build dams to provide irrigation and relatively like stable water sources for agriculture.
• 3:57
  SPEAKER_00: That was one of the first dams that humans ever built, was basically to make an easy reservoir to draw irrigation from.
• 4:03
  SPEAKER_00: And then in the in the mid-1900s, we started building massive dams to produce power.
• 4:09
  SPEAKER_00: And that kind of continues today, although that's declined, at least in North America.
• 4:14
  SPEAKER_00: It has quite a bit.
• 4:15
  SPEAKER_01: It it has it has declined.
• 4:17
  SPEAKER_01: The building of new dams has declined pretty significantly, uh, which is one of the issues that we have to touch on, right?
• 4:23
  SPEAKER_00: Yeah, absolutely.
• 4:24
  SPEAKER_01: Yeah.
• 4:24
  SPEAKER_01: So let's let's just some statistics.
• 4:27
  SPEAKER_01: Is that a good time for that right now?
• 4:28
  SPEAKER_00: Absolutely.
• 4:29
  SPEAKER_00: Let's hit some statistics.
• 4:30
  SPEAKER_00: I mean, before we get into that, I it the statistics are interesting here in part because infrastructure has been in the political, at least in the United States, infrastructure has been in the political spotlight a little bit recently, talking about U.S.
• 4:43
  SPEAKER_00: infrastructure and infrastructure bills and spending and stuff.
• 4:47
  SPEAKER_00: And dams are one major component of that.
• 4:50
  SPEAKER_00: So what are some stats throw some stats at me, Chris?
• 4:52
  SPEAKER_00: What do we got?
• 4:53
  SPEAKER_01: We have over 91,000 dams in the United States alone.
• 4:57
  SPEAKER_00: Wow, that's amazing.
• 4:59
  SPEAKER_01: It is, it is.
• 5:00
  SPEAKER_00: I would have never guessed.
• 5:02
  SPEAKER_01: The amount of water that they impound is over 600,000 miles of river or 17% of the rivers in the United States.
• 5:12
  SPEAKER_01: Holy shit.
• 5:14
  SPEAKER_00: Wow.
• 5:14
  SPEAKER_00: That is a ton.
• 5:15
  SPEAKER_00: So by impound, can you quickly define what imp what we mean by impound?
• 5:19
  SPEAKER_01: Yeah, if you build a dam across a river, then the upstream from the dam, you're going to create a reservoir.
• 5:26
  SPEAKER_01: And that is the impoundment of the water.
• 5:28
  SPEAKER_01: It's basically a lake behind the dam.
• 5:30
  SPEAKER_01: That's all we're talking about.
• 5:31
  SPEAKER_01: It's it's holding it back.
• 5:33
  SPEAKER_00: So 17% of the rivers in the United States are actually not rivers anymore, they're lakes because of these 91,000 dams.
• 5:40
  SPEAKER_00: That's amazing.
• 5:41
  SPEAKER_00: That's an amazing stat.
• 5:42
  SPEAKER_00: I had no idea it was so high.
• 5:44
  SPEAKER_01: But the average age of a dam in the United States is over 59 years old.
• 5:49
  SPEAKER_01: Wow.
• 5:50
  SPEAKER_01: That's becoming an issue.
• 5:52
  SPEAKER_01: You know, that's old.
• 5:53
  SPEAKER_01: The number of what we call high hazard potential dams is over 15,000 and is increasing every year.
• 6:01
  SPEAKER_00: Wow.
• 6:01
  SPEAKER_00: So it's one-sixth of the total dams in the U.S.
• 6:04
  SPEAKER_00: are ranked as high hazard.
• 6:05
  SPEAKER_00: And we're going to talk about a couple dams that failed because in part they were high hazard ones.
• 6:10
  SPEAKER_00: So this is where the infrastructure bill kind of fits in, or infrastructure discussion of spending money to kind of help rebuild some of these dams.
• 6:17
  SPEAKER_01: Exactly.
• 6:18
  SPEAKER_01: You know, as I was looking into this, I thought a lot about this, that it's an investment and it's it's expensive, right?
• 6:24
  SPEAKER_01: To fix something like this.
• 6:26
  SPEAKER_01: Okay.
• 6:27
  SPEAKER_01: So what it yeah, what is that?
• 6:28
  SPEAKER_01: It is estimated that over$70 billion is needed to properly upgrade these high-risk potential dams.
• 6:37
  SPEAKER_01: Okay.
• 6:38
  SPEAKER_01: $70 billion.
• 6:40
  SPEAKER_01: But for perspective, we spend$425 billion each year on our road infrastructure.
• 6:48
  SPEAKER_00: Oh, wow.
• 6:49
  SPEAKER_00: Okay.
• 6:49
  SPEAKER_01: So I, you know, that just kind of drives it home.
• 6:52
  SPEAKER_01: It's a it's about its priority, right?
• 6:54
  SPEAKER_01: It that's what this comes down to.
• 6:56
  SPEAKER_00: Totally.
• 6:57
  SPEAKER_01: We have a lot of dams that are suffering from neglect, um, and in a lack of investment in this infrastructure needed to keep them up.
• 7:06
  SPEAKER_00: And we'll touch on some of the reinvestment potential uh later on at the end of this podcast.
• 7:11
  SPEAKER_00: But dams, you know, they're really they're really interesting to us because we sort of put this artificial feature in a stream, which is it has a uh an evolving system.
• 7:23
  SPEAKER_00: Streams are very dynamic from a geological and geoscience perspective and an ecological perspective.
• 7:28
  SPEAKER_00: And then you put this big dam in there, and you know, the there's unintended consequences, there's intended consequences, there's great benefits, and there's some downsides to building dams as well.
• 7:38
  SPEAKER_00: It's a really interesting thing to think about from a geoscience perspective, and geoscientists play a role in the discussion around every dam that gets built or renovated or torn down.
• 7:48
  SPEAKER_00: So let's get into one relatively unknown dam failure, which is the Long Lake Dam in Rocky Mountain National Park.
• 7:56
  SPEAKER_00: And Chris, you know the story fairly well.
• 7:58
  SPEAKER_00: So, so what was going on?
• 8:00
  SPEAKER_01: Yeah, I I am very familiar with this because this happened in 1982.
• 8:04
  SPEAKER_01: This happened at a time when I was going to Rocky Mount National Park every summer.
• 8:10
  SPEAKER_01: Um, I was, you know, 11 years old at the time that this damage was.
• 8:14
  SPEAKER_00: No, don't date yourself, Chris.
• 8:15
  SPEAKER_00: Don't date yourself.
• 8:16
  SPEAKER_00: I just did.
• 8:17
  SPEAKER_01: I shouldn't have done that.
• 8:19
  SPEAKER_01: Dang it.
• 8:21
  SPEAKER_01: But anyway, uh, yeah, so I'm I'm really familiar with this story.
• 8:25
  SPEAKER_01: And you know, when I drive into Rocky Mount National Park from the east, I can see uh the damage and and the destruction that's still really, really visible.
• 8:35
  SPEAKER_01: It's in Rocky Mount National Park, and I found that interesting too.
• 8:38
  SPEAKER_01: You know, that we there are a lot of dams that actually are within the national parks, but this dam is 11,000 feet above sea level.
• 8:46
  SPEAKER_01: Okay, so this was just a natural glacial lake, like a tarn.
• 8:50
  SPEAKER_01: Well, it wasn't like a tarn, this was a natural great glacial lake, a tarn.
• 8:54
  SPEAKER_01: Yeah, and it was which we'll discuss later.
• 8:58
  SPEAKER_00: If you don't know that term, you don't need to know it for this story.
• 9:00
  SPEAKER_01: But they're beautiful.
• 9:01
  SPEAKER_01: Yeah, anyway, it was this was built in 1903 to increase the storage capacity of the lake.
• 9:09
  SPEAKER_01: So the dam was 560 feet long, 26 feet high, you know.
• 9:15
  SPEAKER_01: Prior to this break in 1982, there were three campsites right along the trail leading up to this lake.
• 9:20
  SPEAKER_01: And then there's one campsite, and this is for mostly backcountry campers, okay?
• 9:25
  SPEAKER_01: One campsite at the lake itself.
• 9:27
  SPEAKER_00: So there's people camping along this, but what actually caused the dam to fail?
• 9:31
  SPEAKER_00: We're talking about a dam failure.
• 9:33
  SPEAKER_00: So what happened that it gave way?
• 9:35
  SPEAKER_01: Yeah, so there was an outlet pipe.
• 9:37
  SPEAKER_01: It had a connection, and at the connection, where they had fused two pipes together, there was a leak.
• 9:43
  SPEAKER_01: And it was shooting water, a high pressurized water, out of this crack in the pipe or out of this faulty connection into the rock alongside of it, you know, around this outflow pipe, right?
• 9:55
  SPEAKER_01: And this this process is called piping.
• 9:58
  SPEAKER_01: It scours away then the sediment and rock around it.
• 10:01
  SPEAKER_00: So you've got high pressure water kind of squirting through sediment, the sediment being the dam itself, and it's just eroding away the dam gradually.
• 10:08
  SPEAKER_01: It's just eroding it away.
• 10:09
  SPEAKER_01: Okay, hey, uh, real quick, this made me think of it at my old house, a storm sewer pipe, and run right down my front yard, right?
• 10:16
  SPEAKER_00: Oh, I remember that old house.
• 10:18
  SPEAKER_00: We now you had a quin pretty cool rock garden in that old house.
• 10:21
  SPEAKER_00: Not that your your rock garden now is better, but it you had a good one.
• 10:25
  SPEAKER_01: That's an interesting story too, Jesse, because you know when I sold that house, I had it written in the contract.
• 10:31
  SPEAKER_01: The rocks that I had, my whole terror uh all the terraces I had, they go with me.
• 10:36
  SPEAKER_01: And my realtor looked at me like, What?
• 10:38
  SPEAKER_01: What the hell is the matter with you?
• 10:39
  SPEAKER_01: I said, Oh no, this is non-negotiable, the rocks go with me.
• 10:43
  SPEAKER_01: So listen, in my front yard, I had piping.
• 10:46
  SPEAKER_01: The storm sewer, we get some raging storms, right in Michigan.
• 10:49
  SPEAKER_01: And and um, so the storm sewer pipes fill up with water completely full.
• 10:54
  SPEAKER_01: And I had a bad connection in my front yard, and so during a bad storm when the pipes were full, that bad connection, piping would shoot a geyser in my front yard.
• 11:03
  SPEAKER_01: But anyway, that's that's exactly how piping works, and I've seen it firsthand.
• 11:08
  SPEAKER_01: And so this just simply weakened the whole structure.
• 11:11
  SPEAKER_01: Um, and so this morning in 1982, 6 a.m., this dam uh begins to break.
• 11:19
  SPEAKER_01: Okay.
• 11:20
  SPEAKER_01: And this breach ended up, and I gave you the dimensions of the dam in the first place, but the breach was 97 feet wide.
• 11:27
  SPEAKER_01: And the lake, a pretty sizable lake anyway, this tarn.
• 11:30
  SPEAKER_01: The lake drained in an hour.
• 11:32
  SPEAKER_01: Oh wow.
• 11:33
  SPEAKER_01: Yeah, that's that's amazing.
• 11:35
  SPEAKER_01: That's that is pretty quick, right?
• 11:37
  SPEAKER_01: At one of the downstream campsites, this person was up early before anyone else was, and he was making coffee and he heard this crescendo, like this building of noise uh off to the side.
• 11:49
  SPEAKER_01: And he sees these trees snapping like toothpicks.
• 11:54
  SPEAKER_01: Boulders are just hurtling to waters screaming at him from 50 feet away.
• 11:59
  SPEAKER_01: That's the sight that this guy sees.
• 12:01
  SPEAKER_00: Well, that's a that's a pretty intimidating sight.
• 12:03
  SPEAKER_00: And it it brings up, you know, an interesting thing about rivers and especially floods, is that you look at these big boulders, and you the statistic we have here is that one of the boulders moved by this flood was actually weighed 450 tons.
• 12:19
  SPEAKER_00: So this is a massive, massive boulder.
• 12:23
  SPEAKER_00: And the the thing about streams is that they have what's called a competency, and the competency is the largest particle size that they can carry.
• 12:32
  SPEAKER_00: So when you're walking up uh if you're on a hike and you're walking up a valley next to a stream, you see massive boulders, and the water's just flowing around those, right?
• 12:43
  SPEAKER_00: But at some stage, those boulders were moved by that river.
• 12:46
  SPEAKER_00: They're often rounded, you know, they're they're obviously been moved by the river and deposited there.
• 12:52
  SPEAKER_00: And so that stream was at flood stage at some point.
• 12:55
  SPEAKER_00: And so the competency is really the maximum particle size, and it increases by the square of the velocity.
• 13:02
  SPEAKER_00: And those of you who are at home, if you have a like a gravel road nearby or a gravel driveway, you've seen competency in action when it rains.
• 13:11
  SPEAKER_00: If you go outside when it rains, you see these like little rivulets forming.
• 13:15
  SPEAKER_00: You know, the water's kind of flowing along the gravel road and it's carrying away the really small sediment, but it's leaving behind the gravelly stuff, the little bit bigger stuff.
• 13:23
  SPEAKER_00: It's because the competency has not been reached.
• 13:26
  SPEAKER_00: So the big stuff stays behind during kind of normal rainstorms, but during flood stage, massive things can be moved.
• 13:34
  SPEAKER_00: And we'll kind of come back to some things about stream dynamics here with water flow.
• 13:39
  SPEAKER_00: But basically, those massive boulders are all being moved during flood stage.
• 13:44
  SPEAKER_00: So most of the erosion, most of the sediment movement happens when a flood happens or when a dam breaks, which is kind of an unnatural flood.
• 13:53
  SPEAKER_00: So then what what happened?
• 13:55
  SPEAKER_00: You know, you got this guy on his campsite, he's waking up for coffee, he's pretty groggy and he sees basically the world ending upstream from him.
• 14:01
  SPEAKER_00: What happens?
• 14:02
  SPEAKER_01: A little over an hour after the first dam breaks, another dam, the Cascade Dam downstream, which is a 17-foot-high concrete dam.
• 14:12
  SPEAKER_01: The other one was just a uh an earthen rock fill dam.
• 14:16
  SPEAKER_01: Okay, uh the lawn lake one was that began to fill.
• 14:20
  SPEAKER_01: So it fills up quickly and begins overtopping, which is just water spilling and just flowing over the top of this dam.
• 14:29
  SPEAKER_01: And uh it does this for 17 minutes before it begins to break.
• 14:34
  SPEAKER_01: Also, it's a domino.
• 14:35
  SPEAKER_01: The lawn lake breaks up at high elevation, this dam overtops for 17 minutes, it breaks, and now you've got downstream camp.
• 14:44
  SPEAKER_01: We're we're beyond the three campsites leading up to the lawn lake.
• 14:49
  SPEAKER_01: Now we're past that now.
• 14:50
  SPEAKER_01: We're we're downstream and we're heading towards Estes Park.
• 14:53
  SPEAKER_01: That's a decent town, right?
• 14:55
  SPEAKER_01: And so a nearby campground, in fact, this downstream campground had over 275 campers that had to be evacuated, and they did it.
• 15:03
  SPEAKER_01: They had the that roughly 20 minutes, right, to get that done.
• 15:07
  SPEAKER_01: Good thing, good ending, I guess, you know.
• 15:09
  SPEAKER_01: And um, all the campers were evacuated except two people.
• 15:13
  SPEAKER_01: Oh man, um, okay, they had actually been evacuated, but they look, I get it.
• 15:18
  SPEAKER_01: They went back to retrieve their gear.
• 15:22
  SPEAKER_00: You're you're a bit of a gear head, I'm a bit of a gear head.
• 15:24
  SPEAKER_01: I am, you you know, you understand that, right?
• 15:27
  SPEAKER_00: You totally go back to get your gear.
• 15:29
  SPEAKER_01: Yeah, and it's a shame because uh they were swept away and uh didn't didn't make it.
• 15:35
  SPEAKER_01: But downstream then Lake Estes is also impounded, it's got a dam, and it's just outside Estes Park, that cool city.
• 15:44
  SPEAKER_01: Uh, but this dam, it filled, it was it ran the risk, you know, it was pushing the envelope.
• 15:51
  SPEAKER_01: But this dam held and everything was over by 9:30.
• 15:55
  SPEAKER_01: Started at 6 a.m., ends at 9 30, done, and a lot happened.
• 16:00
  SPEAKER_00: I mean, yeah, it's a pretty, pretty dramatic couple hours, but it's really only a couple hours.
• 16:04
  SPEAKER_00: And this speaks to something interesting about rivers because this is in a relatively small, relatively narrow and steep mountain river system.
• 16:13
  SPEAKER_00: And we're gonna talk in a couple minutes about a dam that failed on a very different style of river and produced a very different style of flooding.
• 16:22
  SPEAKER_00: And, you know, it just speaks to the geoscience behind dams and dam failure and where you place dams because these two are very different events with very different outcomes, and you have to think about what might happen, the potential risk when you start thinking about dams in a very different way, depending on the uniqueness of each river system.
• 16:41
  SPEAKER_00: With that, let's let's get into the geoscience behind dams.
• 16:44
  SPEAKER_00: You know, what do they do to rivers?
• 16:46
  SPEAKER_00: It's natural as humans to think of rivers as relatively constant features, but that's not the case even without a dam.
• 16:53
  SPEAKER_00: But what happens when you put a dam in the river?
• 16:55
  SPEAKER_01: All right, so here we go.
• 16:56
  SPEAKER_01: Then this is what gets me fired up about dams is you know, shoot, I can't, I can't help, I can't stop it.
• 17:03
  SPEAKER_01: It's totally cool.
• 17:04
  SPEAKER_01: So I like to simplify things, and dams do really do two things.
• 17:07
  SPEAKER_00: They're two you yeah, you simplify things more out of necessity than desire, but so true.
• 17:14
  SPEAKER_01: That is so true.
• 17:15
  SPEAKER_01: I'm on you.
• 17:16
  SPEAKER_01: I'm a simple person, but that's all right.
• 17:18
  SPEAKER_00: Oh man, me too, me too.
• 17:19
  SPEAKER_01: So yeah, two main factors, right?
• 17:22
  SPEAKER_01: You have water and you have sediment.
• 17:24
  SPEAKER_01: These are the two things that really have to be considered.
• 17:28
  SPEAKER_00: So water and the sediment that it carries, or the sediment that it moves in some way, the competence, you know, the boulders, the sand, the silt.
• 17:36
  SPEAKER_00: Yep.
• 17:36
  SPEAKER_01: So if you take the course of a river before a dam was built, you basically had a river with what we call in geology a river in equilibrium.
• 17:46
  SPEAKER_01: There's no net anything going on.
• 17:48
  SPEAKER_01: You have sediment being moved downstream, of course.
• 17:51
  SPEAKER_01: Sand is rolling and silt is being carried and so on.
• 17:54
  SPEAKER_01: But for everything that gets moved downstream, something else gets deposited in its place, and it's in equilibrium.
• 17:59
  SPEAKER_01: Nothing is really happening.
• 18:00
  SPEAKER_00: Now, that's on human timescales.
• 18:02
  SPEAKER_00: Over the course of long periods of time, streams are moving, but it's pretty slow for our purposes, for human purposes.
• 18:10
  SPEAKER_00: So we've got this river in some sort of equilibrium, and you build a dam, and we build this lake of artificial lake on the on the river.
• 18:18
  SPEAKER_00: What happens upstream and then what happens downstream, Chris?
• 18:21
  SPEAKER_01: Bottom line is this is that when water slows down, so you know, the river's flowing and it flows into this newly formed lake that's there only because the dam is there, the water slows down then.
• 18:33
  SPEAKER_01: It comes to a stop, uh, essentially.
• 18:36
  SPEAKER_01: And whenever water slows down and stops, sediment gets deposited.
• 18:40
  SPEAKER_00: That's right.
• 18:41
  SPEAKER_00: So think back to competency.
• 18:42
  SPEAKER_00: You know, the the maximum particle size is related to the square of the velocity.
• 18:47
  SPEAKER_00: If you slow down the river, all that big stuff gets dumped out.
• 18:50
  SPEAKER_00: It can no longer carry the big grains, and so it just drops them.
• 18:54
  SPEAKER_01: And even the really fine stuff is going to settle out because the water does come to a halt.
• 18:59
  SPEAKER_01: I mean, you've you've stopped the flow of that river, and that's what happens then in on the upstream side of a dam is this deposition of sediment.
• 19:07
  SPEAKER_01: And that is the thing that all dams are going to have to address at some point, and and usually this should be an ongoing process.
• 19:15
  SPEAKER_00: So if you think that you build a 10-foot dam and then sediment's accumulating beneath at the bottom of that, and then you have one foot of sediment in the bottom of your lake, and you have you know two feet of sediment in the bottom of your lake.
• 19:27
  SPEAKER_00: Now your lake is only nine feet deep, then eight feet deep, then seven feet deep.
• 19:31
  SPEAKER_00: And so if you're trying to like store potential energy with the lake, or if you're trying to create a recreational lake, or if you're trying to store water for irrigation, your lake is getting smaller.
• 19:41
  SPEAKER_00: The volume of water you have behind the dam is getting smaller because sediment is accumulating in there.
• 19:45
  SPEAKER_00: So you either got to build a bigger dam or you got to get rid of the sediment in some way.
• 19:49
  SPEAKER_01: If you don't do anything, then it's a matter of time.
• 19:53
  SPEAKER_01: Uh and I'm talking about on the order of decades, it's a matter of decades until your dam is essentially useless.
• 20:01
  SPEAKER_01: You know, we've been saying this a lot.
• 20:03
  SPEAKER_01: How do you deal with this?
• 20:04
  SPEAKER_01: But the most common way to deal with this sediment accumulation in the reservoir behind the dam is to dredge it, you know, scoop this out.
• 20:12
  SPEAKER_01: So, what happens downstream, Jesse?
• 20:14
  SPEAKER_00: Yeah, so downstream, it's it's basically the opposite effect.
• 20:17
  SPEAKER_00: You've taken your river that's in equilibrium, it's carrying sediment downstream, you put a dam in there, and now all the sediment's going into the lake, and then the water flowing out of the dam is what's termed hungry water.
• 20:29
  SPEAKER_00: And it's hungry because it can carry sediment, but it no longer has any sediment in it.
• 20:35
  SPEAKER_01: I love that analogy.
• 20:37
  SPEAKER_01: Hungry water downstream.
• 20:38
  SPEAKER_01: That's it's perfect.
• 20:39
  SPEAKER_01: It's a great term.
• 20:40
  SPEAKER_01: That's the perfect analogy.
• 20:41
  SPEAKER_00: Yeah, it's a great term.
• 20:42
  SPEAKER_00: And you know, it comes from one of these classic papers that looked into what happens when you put a dam on a river system.
• 20:47
  SPEAKER_00: So there's a couple things.
• 20:49
  SPEAKER_00: First off, you have this hungry water.
• 20:51
  SPEAKER_00: It can carry sediment, it's used to carrying sediment, it naturally carries some sediment downstream, but all the sediment is in the lake above it, so it comes out of the dam and it's got no sediment in it.
• 21:00
  SPEAKER_00: So it basically clean, it scoops up any sediment that is there.
• 21:05
  SPEAKER_00: And what that means is that the river is downcutting faster, so it's eroding quicker, it's removing any sand or particles that are in that system.
• 21:14
  SPEAKER_00: It basically scours a lot more quickly than it normally would.
• 21:18
  SPEAKER_00: Clean water is fast water.
• 21:20
  SPEAKER_00: And so when people are building dams, they are now considering that they have to basically seed that part right below the dam with sediment.
• 21:28
  SPEAKER_00: So they put a whole bunch of sediment in there artificially so that the hungry water has something to take away to eat, eat, eat from it.
• 21:34
  SPEAKER_01: And this is something, Jesse, that they can do with the dredged water on the other side.
• 21:38
  SPEAKER_01: They dredge it and they have to move it to the other side and seed the river with that with that freshly dredged.
• 21:44
  SPEAKER_00: And the and the other thing that happens downstream is more ecological.
• 21:48
  SPEAKER_00: And this is if you consider a lake, the sun heats up the surface of the water in a lake, and so the bottom is typically a lot cooler.
• 21:55
  SPEAKER_00: So if you put a dam in there, the water often comes out of the bottom of the dam.
• 21:58
  SPEAKER_00: And so the water.
• 22:00
  SPEAKER_00: Is actually a lot colder.
• 22:01
  SPEAKER_00: There's the water coming into the lake is warm or intermediate temperature.
• 22:05
  SPEAKER_00: The water coming out of the bottom of the dam is pretty cold.
• 22:08
  SPEAKER_00: And so it changes the natural ecology of the lake.
• 22:11
  SPEAKER_00: And in some ways, I'm a I'm a trout fisherman.
• 22:14
  SPEAKER_00: So the tailwater fisheries, which are tailwaters right below dams, are often quite good for trout because cold water, more oxygen, more better for trout, but it changes the natural habitat a little bit and does stuff to the ecology.
• 22:26
  SPEAKER_00: So you know, these are things to consider.
• 22:29
  SPEAKER_01: Can I interject a second?
• 22:30
  SPEAKER_01: I just want to um you know, for the viewer, like when you look at a dam, then I want I want people to look at dams differently.
• 22:37
  SPEAKER_01: You look at the upside, the upstream side of a dam, and you see this massively impounded at a high-level lake, right?
• 22:46
  SPEAKER_01: Downstream from the dam, it's a different scene entirely.
• 22:50
  SPEAKER_00: All right.
• 22:51
  SPEAKER_00: So, so we're gonna talk now about another dam that failed, which is the Edenville Dam.
• 22:56
  SPEAKER_00: And this is near the confluence of the Tittabawasi and Tobacco Rivers, and these are in Midland Michigan, so kind of it's basically right in the middle of the state.
• 23:05
  SPEAKER_00: And this is a very different style of river from the dam that we talked about earlier in the Rocky Mountains.
• 23:12
  SPEAKER_00: This is a river that's in a relatively flat part of the country.
• 23:16
  SPEAKER_00: It's a river that we call meandering, so it means it meanders back and forth, it kind of winds, there's lots of turns, and it's not flowing necessarily downhill that much.
• 23:26
  SPEAKER_00: It's kind of flowing a little bit more side to side than it is straight down.
• 23:30
  SPEAKER_00: And it carries a lot of sediment, it wanders around because it's relatively flat lying.
• 23:36
  SPEAKER_00: The flooding area is quite a bit larger.
• 23:39
  SPEAKER_00: There's just a more um, there's just more area that can be flooded.
• 23:43
  SPEAKER_00: And so, because of that, the dam has to be larger.
• 23:45
  SPEAKER_00: So, this dam, the Edenville dam that we're going to talk about, was much larger than the Lawn Lake Dam.
• 23:52
  SPEAKER_00: It is a 6,600-foot wide dam that's four Sears Towers end to end.
• 23:58
  SPEAKER_00: That's kind of amazing.
• 24:00
  SPEAKER_00: Is that right?
• 24:00
  SPEAKER_00: That's amazing.
• 24:01
  SPEAKER_00: Um, and it was built a long time ago, almost a hundred years ago, 96 to be exact, in 2020.
• 24:06
  SPEAKER_00: So, Chris, what happened to this dam?
• 24:08
  SPEAKER_01: Yeah, um, so I mean, first of all, it was it was the two dams, right?
• 24:12
  SPEAKER_01: The Edenville and then the Sanford Dam.
• 24:14
  SPEAKER_01: And the Edenville is the upstream dam, the Sanford's the downstream dam.
• 24:18
  SPEAKER_01: They were both built around the uh around the same time, roughly a hundred years ago.
• 24:23
  SPEAKER_01: Okay look, it's kind of a story, Jesse, and and I want to like tell it that way because I want to do it justice because I think it deserves it.
• 24:31
  SPEAKER_01: This is May 19 of 2020.
• 24:34
  SPEAKER_01: You know, Michigan, we were hard hit by the pandemic early on and was experiencing heavy rain in May leading up to this.
• 24:44
  SPEAKER_01: On May 19th, then, 6 p.m., the Edenville Dam broke.
• 24:49
  SPEAKER_01: Just broke, and it released a raging torrent of water heading downstream to the nearby Sanford Dam.
• 24:56
  SPEAKER_01: Three hours later, after this first dam broke, the order for the Midland area to evacuate came.
• 25:04
  SPEAKER_00: And Midland is a is a relatively sizable town in the south of Michigan.
• 25:07
  SPEAKER_01: Yeah, and the all the suburbs sprawling.
• 25:10
  SPEAKER_01: You know, so yeah, this 9 p.m.
• 25:12
  SPEAKER_01: the the order came to evacuate.
• 25:14
  SPEAKER_01: Over 2,000 homes were damaged.
• 25:17
  SPEAKER_00: Yeah, the the evacuation covered about 10,000 people, if I remember correctly.
• 25:21
  SPEAKER_00: Is that right?
• 25:21
  SPEAKER_01: Yeah, you couldn't get away from the story and if you lived in it anywhere around the area.
• 25:26
  SPEAKER_00: Oh, I remember seeing it on national news stations in from Pennsylvania for sure.
• 25:30
  SPEAKER_01: And looking at the aftermath of this, it it literally looked like a tsunami had hit.
• 25:35
  SPEAKER_00: So if we go back to the timeline, the Edenville Dam fails, then you know the the Sanford Lake builds up water.
• 25:42
  SPEAKER_00: We get an evacuation order, 10,000 people ordered to evacuate.
• 25:46
  SPEAKER_00: Because the Sanford Dam might fail and flood Midland.
• 25:49
  SPEAKER_00: The Sanford Dam doesn't actually breach, but it does overtop, which means the lake builds up to high enough levels that it flows over.
• 25:56
  SPEAKER_00: And the point here is that this is a very different style of river.
• 26:00
  SPEAKER_00: It it impacts a lot more people.
• 26:02
  SPEAKER_00: And if you go online, if you listen to this and you need some visuals, go online.
• 26:05
  SPEAKER_00: There's tons of footage from the Detroit Free Press or MLive or whatever that show what happens during this flood stage event and during this dam failure event.
• 26:14
  SPEAKER_00: It's really impressive.
• 26:15
  SPEAKER_00: The point here for us is that it took a long time, three hours until the evacuation order proceeded.
• 26:22
  SPEAKER_00: Three hours was the total time of the dam failure in the Lawn Lake Dam failure up in the Rocky Mountain National Park.
• 26:31
  SPEAKER_00: So it's a very different style of river.
• 26:33
  SPEAKER_00: It happens a little bit slower, and it's much more widespread disaster event.
• 26:38
  SPEAKER_00: I mean, you're not seeing you know trees being knocked down as the flood is flowing down this valley.
• 26:43
  SPEAKER_00: Instead, you're seeing water levels rising pretty rapidly over an entire town.
• 26:48
  SPEAKER_01: That is a really good point you make.
• 26:50
  SPEAKER_01: This soap opera went on for days.
• 26:53
  SPEAKER_01: It was just it was a crescendo, but it was a slow crescendo, the slow buildup, and then it broke, and then things got real uh pretty fast.
• 27:01
  SPEAKER_01: You know, the lake is now gone.
• 27:03
  SPEAKER_01: The the reservoir above the Edenville Dam is gone.
• 27:06
  SPEAKER_01: And so these people that had lakefront property, they now have just a gigantic sandbox.
• 27:12
  SPEAKER_00: That's right.
• 27:13
  SPEAKER_01: I mean, I don't mean to laugh at that because that's you know, and it's really sad.
• 27:17
  SPEAKER_00: That's right.
• 27:18
  SPEAKER_01: It's very sad because they they don't have any way to sell this now.
• 27:21
  SPEAKER_01: Uh you know, lakefront property sells for a whole lot more than a gigantic sandbox does.
• 27:26
  SPEAKER_00: Yeah, that's right.
• 27:27
  SPEAKER_00: And so the owners of of these properties are you know undergoing there's lots of lawsuits about this dam failure.
• 27:34
  SPEAKER_00: Um, there's loads of data that you can find online about sort of regulatory issues.
• 27:38
  SPEAKER_01: In 2006, Jesse, both of these dams were bought for 4.8 million dollars as a tax shelter by four people.
• 27:49
  SPEAKER_01: And and I found this really surprising, you know.
• 27:51
  SPEAKER_01: But interestingly, you dig you dig a little deeper in this 56%, Jesse.
• 27:56
  SPEAKER_01: 56% of all the dams in the United States are owned privately.
• 28:02
  SPEAKER_01: Isn't that amazing?
• 28:03
  SPEAKER_00: That's a really interesting statistic.
• 28:04
  SPEAKER_00: I think crazy.
• 28:05
  SPEAKER_00: I had no idea.
• 28:06
  SPEAKER_00: Yeah.
• 28:06
  SPEAKER_00: I mean, most of those are probably the small ones.
• 28:08
  SPEAKER_00: I mean, the big ones, the Hoover Dam, these are not necessarily privately owned, but the small ones, it's still they can be very impactful.
• 28:14
  SPEAKER_01: We have 91,000 dams in the US, 56% of them are owned privately, and the majority of them are in the risky condition.
• 28:21
  SPEAKER_01: So the story behind what happened here to me reads more like a soap opera than anything else.
• 28:27
  SPEAKER_01: These landowners around the lakes, they were really they were aware of the condition of the dam and were in constant battle with the owners.
• 28:38
  SPEAKER_01: The Federal Energy Regulation Commission was hounding the owners to maintain the dams and to make repairs.
• 28:45
  SPEAKER_01: The Midland flood is a case study then with our problem of infrastructure and our lack of investment in it.
• 28:54
  SPEAKER_01: I think that speaks to a problem when you talk about 56% of all of our dams being privately owned.
• 29:01
  SPEAKER_01: Um, I don't know, that can be a problem.
• 29:03
  SPEAKER_00: But so if we bring this back, let's let's let's end talking about you know kind of the future of dams and and where dams are going.
• 29:11
  SPEAKER_00: We highlighted earlier that we have like 90,000 or 91,000 dams in the United States alone.
• 29:18
  SPEAKER_00: And in much of the the developed world, there's loads of dams kind of everywhere.
• 29:23
  SPEAKER_00: And we've been using these things for, and as humans, we've been using them to control irrigation, to control flooding, and to generate hydroelectric power since about the 1880s or so.
• 29:35
  SPEAKER_00: The first hydroelectric power plant was actually in near Appleton, Wisconsin.
• 29:39
  SPEAKER_00: Um, in the US, so this this is something that I kind of got interested in when we were looking at dams, is that there's about 2,500 dams in the US that produce hydropower.
• 29:48
  SPEAKER_00: So these are electricity-producing dams.
• 29:50
  SPEAKER_00: And this is create a reservoir and then let the water flow in a regulated fashion downhill, drive turbines, generate electricity, right?
• 29:59
  SPEAKER_00: So about 3% of the dams in the United States produce electrical power.
• 30:04
  SPEAKER_00: Wait a minute, what?
• 30:05
  SPEAKER_00: About 3% of the dams in the United States produce power.
• 30:09
  SPEAKER_00: Really?
• 30:10
  SPEAKER_00: Yeah, so and they produce 78 gigawatts of hydropower, which I don't really know what a gigawatt of hydropower meant, but it's basically enough to power 31 million homes annually.
• 30:19
  SPEAKER_00: So that's a lot.
• 30:21
  SPEAKER_00: That's a lot of power.
• 30:22
  SPEAKER_00: It ends up being around 6% of the total electric production in the United States.
• 30:27
  SPEAKER_00: And so it's a really important part of our grid system, of our economy.
• 30:32
  SPEAKER_00: And as you let in with, it's a really interesting intersection between geoscience and engineering and biology and ecology and all these interesting things.
• 30:41
  SPEAKER_00: So we talked about these failing dams.
• 30:42
  SPEAKER_00: And one interesting thing is that there's all these proposals out there for taking other dams that are not hydroelectric dams and kind of converting them, putting little small hydroelectric power plants on these old aging dams, most of which, or many of which are rated in the high risk category, and kind of renovating them and having them generate electricity for us.
• 31:04
  SPEAKER_01: What would that look like?
• 31:05
  SPEAKER_01: I don't under I don't I'm and I'm honestly asking, like, I don't know what that looks like.
• 31:09
  SPEAKER_00: I mean, I don't really know what the uh engineering perspective, this is in the engineers department for sure.
• 31:14
  SPEAKER_00: So I don't know.
• 31:14
  SPEAKER_01: But is it a feasible thing?
• 31:16
  SPEAKER_00: I uh it seems feasible.
• 31:17
  SPEAKER_00: It seems like there's a decent amount of cost involved for sure.
• 31:21
  SPEAKER_00: But basically, if we did this for the top 100 dams that could be converted this way, it would produce enough power to power another five million homes, roughly.
• 31:30
  SPEAKER_00: And the other thing that's interesting is that it would take place mostly in the Midwest or in the Northeast, where solar and wind power are relatively inefficient.
• 31:40
  SPEAKER_00: So it was kind of an interesting prospect, I thought.
• 31:43
  SPEAKER_00: And looking towards the future of dams in the United States, uh, it was kind of an interesting statistic.
• 31:49
  SPEAKER_01: So I I just want to because I want to say one thing, okay?
• 31:52
  SPEAKER_01: Uh like I am absolutely shocked uh that you said that only three percent of dams produce power.
• 31:59
  SPEAKER_01: Like, I did not know that.
• 32:01
  SPEAKER_01: That is to me, that freaking floors me.
• 32:05
  SPEAKER_01: I would have thought 30%.
• 32:07
  SPEAKER_00: It's for me when you think of dams, I think of the Hoover Dam.
• 32:10
  SPEAKER_00: You know, I think of these massive infrastructure projects that were really depression-era projects or into the 1950s and 60s.
• 32:17
  SPEAKER_00: This is the era of big dam building of hydroelectric dam building.
• 32:21
  SPEAKER_00: That era really has declined.
• 32:23
  SPEAKER_00: And actually, the kilowatt hours of hydroelectric production has basically plateaued since 1970.
• 32:29
  SPEAKER_00: We're not building any, at least in in North America, we're not building any massive dams anymore.
• 32:34
  SPEAKER_00: In China and in developing countries, they are uh not so much here because we realize the ecologic and you know unintended consequences of dams, perhaps.
• 32:42
  SPEAKER_00: And the the last thing that I'll highlight was that dam removal is a big deal right now, and there's been almost 1,700 dams have been removed since 1990 in the United States alone.
• 32:53
  SPEAKER_00: So people are looking at these dams and their the infrastructure's failing.
• 32:58
  SPEAKER_00: Instead of having the dam fail catastrophically, it might be better to just take it out and you know let the stream get back to normal, although it never really gets back to normal.
• 33:08
  SPEAKER_01: Yeah, it's interesting, you know, because we have this this idea going on in in Grand Rapids where we're from, right?
• 33:14
  SPEAKER_01: The you the return the rapids to the Grand Rapids.
• 33:16
  SPEAKER_00: I mean Absolutely.
• 33:18
  SPEAKER_00: And actually, the first industrial hydropower plant was in Grand Rapids, the Wolverine Chair Factory in 1880.
• 33:23
  SPEAKER_00: Put a you started to use the water system to generate, you know, of mechanical energy.
• 33:28
  SPEAKER_00: Even that requires geoscience knowledge.
• 33:30
  SPEAKER_00: When you're thinking about what happens if we take this dam that's 150 years old and it's been sitting in the river for that long, what happens if we take it out?
• 33:38
  SPEAKER_00: You have to consider that.
• 33:39
  SPEAKER_00: Absolutely.
• 33:40
  SPEAKER_01: Well, you have to consider the unintended consequences and the intended consequences, right?
• 33:45
  SPEAKER_01: Which is really hard to get a hold of, you know.
• 33:47
  SPEAKER_01: I love doing this with you.
• 33:49
  SPEAKER_01: I look forward to doing this.
• 33:50
  SPEAKER_01: I had a blast digging into this and and was just looking forward all day because I knew at the end of my day I was gonna get to talk to you and BS around some geology and stuff like that.
• 34:00
  SPEAKER_01: It's just cool stuff.
• 34:01
  SPEAKER_01: I love it.
• 34:01
  SPEAKER_01: Yeah.
• 34:02
  SPEAKER_00: Like I like I said, I was a little bit just I was a little bit hesitant to dive into dams, but once I did, I mean, I was driving down the road just today.
• 34:08
  SPEAKER_00: I was like, oh, there's a dam.
• 34:09
  SPEAKER_00: Oh, interesting.
• 34:10
  SPEAKER_00: Look at the upstream, look at the downstream.
• 34:11
  SPEAKER_00: Wow, that's so interesting.
• 34:12
  SPEAKER_01: So that's what we want for you, the listener, is to look at things a little differently.
• 34:16
  SPEAKER_01: You know, you look at dams differently now, and that's a it's a pretty simple thing, but that's what this is all about.
• 34:20
  SPEAKER_00: That's what I love about geology.
• 34:22
  SPEAKER_00: I agree completely.
• 34:23
  SPEAKER_00: And most of you live near a dam within driving distance of a dam.
• 34:26
  SPEAKER_00: Next time you were driving past it or walking along a river with a dam on it, check it out, think about it.
• 34:30
  SPEAKER_00: Think about what happens if we take that dam out, what happens if we make it bigger?
• 34:34
  SPEAKER_00: It's it's interesting stuff.
• 34:36
  SPEAKER_00: All right.
• 34:36
  SPEAKER_00: You got it.
• 34:37
  SPEAKER_00: All right, with that, thanks for tuning in.
• 34:38
  SPEAKER_00: And again, if you got something out of this, if you enjoyed it, just share it with even just one other person that you think might enjoy Planet Geo.
• 34:46
  SPEAKER_00: And uh stay tuned.
• 34:47
  SPEAKER_00: We got our interview with Dr.
• 34:49
  SPEAKER_00: Jackie Farady coming up in a couple weeks, and that was a fun one to do, and we look forward to sharing that with you.
• 34:55
  SPEAKER_01: Well, she's an astronomer, she is the astronomer.
• 34:58
  SPEAKER_00: Oh, totally cool.
• 34:59
  SPEAKER_00: Super fun stuff.
• 35:00
  SPEAKER_00: Yeah, absolutely.
• 35:01
  SPEAKER_00: All right, take care, everybody.
• 35:03
  SPEAKER_00: Thanks.