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How the Hoover Dam Works, Part II · Stuff You Should Know

0:00
Speaker 1: Hey, everybody, This is Chuck Hello, New York. Specifically, I'm
0:04
Speaker 1: coming out there next week, next Tuesday, to perform as
0:08
Speaker 1: a part of UH, the We Knows Parenting podcast. My
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Speaker 1: buddies Beth Newell and Pete McNerney. Pete, He's Peter. What
0:16
Speaker 1: am I talking about? Uh? They're performing live We Knows
0:19
Speaker 1: Parenting for the first time at Little Fields in Brooklyn
0:23
Speaker 1: on Tuesday night, and I'm gonna be there. I'm coming
0:27
Speaker 1: up for this. I'm gonna take the stage with them.
0:28
Speaker 1: I'm gonna talk kids, and it's a good chance to
0:31
Speaker 1: uh to say hi. Emily is gonna be there to everyone,
0:33
Speaker 1: So come on out if you are in the New
0:35
Speaker 1: York area Tuesday. That's this Tuesday at Little Fields in Brooklyn.
0:41
Speaker 1: Go to We Knows Parenting dot com and buy tickets
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Speaker 1: there and UH, I would love to meet you. So
0:47
Speaker 1: come on out and say hello. Welcome to Stuff You
0:50
Speaker 1: should know, a production of I Heart Radios How Stuff Works. Hey,
1:00
Speaker 1: and welcome to the podcast. I'm Josh Clark, There's Charles w.
1:04
Speaker 1: Chuck Brian, there's Jerry over there. And this is part
1:06
Speaker 1: due the sequel of Hoover Damn. Let's find out what happens.
1:13
Speaker 1: So I think the last thing I said was they
1:16
Speaker 1: poured the last bucket of concrete on and the end,
1:21
Speaker 1: so let's do listener mail. Okay, I'm getting definitely worth
1:26
Speaker 1: the two part um. Okay, Chuck. So they poured the
1:30
Speaker 1: last bucket of concrete, they grouded everything off, and all
1:34
Speaker 1: of a sudden, you now have one solid sheet of damn, Hoover, damn,
1:40
Speaker 1: and um. At the bottom, it's much much wider than
1:43
Speaker 1: it is at the top. It's like six plus feet
1:45
Speaker 1: at the bottom, that's how wide it is. At the
1:48
Speaker 1: top is forty five, which still feels substantial. And indeed
1:51
Speaker 1: it's enough to have a two lane highway going over it,
1:55
Speaker 1: and for a very long time, for sixty something years,
1:59
Speaker 1: I've leave that was how you got um from Arizona
2:04
Speaker 1: to Las Vegas. You had to drive over the Hoover
2:07
Speaker 1: dam on top of it, which seems just about as
2:10
Speaker 1: bone headed as it gets. But I guess they were.
2:13
Speaker 1: They were They really wanted the gift shop money from
2:15
Speaker 1: everybody they could get their hands on. Yeah, it was
2:18
Speaker 1: kind of cool to have been forced to do that,
2:20
Speaker 1: because whether you liked it or not, you were gonna
2:23
Speaker 1: see an amazing thing. Um. But eventually, like you, like
2:26
Speaker 1: you were hinting at, traffic just picked up and picked
2:29
Speaker 1: up and they're like, you know what, this isn't great
2:31
Speaker 1: to have all these cars um driving over this thing
2:34
Speaker 1: every day. So let's build a bridge. You know what
2:36
Speaker 1: we'll do. Let's build the longest concrete gravity arch bridge
2:40
Speaker 1: on in North America. Which is appropriate because again, if
2:43
Speaker 1: you take a gravity arch bridge and lay it on
2:45
Speaker 1: its side, you've got basically the Hoover Dam right there. Yeah.
2:48
Speaker 1: So it spans over a thousand feet about a thousand
2:51
Speaker 1: sixty feet of the Black Canyon, just south of the
2:55
Speaker 1: old Route, nine feet above the canyon. Have you been
2:58
Speaker 1: to this bridge? Yeah, it's cool, Like I have driven
3:03
Speaker 1: over that bridge since I visited the damn itself in
3:05
Speaker 1: ninety six. And you get a great view from up there, yes,
3:09
Speaker 1: you do. You also get to experience the most terror
3:13
Speaker 1: you can possibly experience on a bridge because the railing
3:17
Speaker 1: is like less than five ft tall. There's no big barrier,
3:21
Speaker 1: there's no nuts, there's no nothing. It's just void right
3:25
Speaker 1: on the other side. It's so scary. But yes, the
3:28
Speaker 1: view is is unparalleled. I don't think you can walk
3:31
Speaker 1: across it, though, can you Yes, you can, Yes, I
3:36
Speaker 1: had no idea. Oh yeah, there's a no, there's a
3:38
Speaker 1: pedestrian walkway and the railing is less than five ft.
3:42
Speaker 1: I didn't notice that. Oh yeah, that's that's why you
3:45
Speaker 1: weren't terrified. You you walk across this thing and it
3:48
Speaker 1: is so scary. Oh my gosh, it's scary. But it's
3:51
Speaker 1: really really amazing, like the most amazing views of Hoover
3:55
Speaker 1: dam Um. Prior to the bridge opening. We're all done
3:59
Speaker 1: like from about this vantage point by helicopter. Now, any
4:02
Speaker 1: smoke can just walk out there, just park and walk
4:04
Speaker 1: and and see it yourself, and it's pretty amazing. You
4:07
Speaker 1: see all sorts of rainbows. We saw a bunch of
4:09
Speaker 1: rainbows while we were there, because the water is flowing
4:12
Speaker 1: out of the damn outlets and um, the sun shining
4:16
Speaker 1: and there's just rainbows. Like you can't you can't throw
4:19
Speaker 1: a rock and not hit a rainbow around there. Well,
4:21
Speaker 1: Bob mould would end up writing a great song, uh,
4:25
Speaker 1: after being inspired by a visit. There a rainbow connection. No,
4:28
Speaker 1: he Bob Moulden remember Sugar sure and Whisker do. Yeah,
4:32
Speaker 1: but Sugar was his band in the early nineties. And uh,
4:35
Speaker 1: he had a great song called Hoover dam I didn't
4:37
Speaker 1: not standing on the edge of the Hoover Damn. That's
4:43
Speaker 1: such a good bob mole. So March one, believe it
4:48
Speaker 1: or not, they finished this thing under budget two years
4:52
Speaker 1: ahead of schedule. Um, yeah, I want to say something
4:56
Speaker 1: about that real quick. Remember they called Frank crow the
4:58
Speaker 1: the guy who was running was the project manager for
5:01
Speaker 1: the whole thing. Crow. They called him hurry up Crow's right.
5:07
Speaker 1: So he um made the company eight million dollars. Remember
5:11
Speaker 1: how they bid the thing out at just twenty four
5:13
Speaker 1: grand over cost. By coming in under budget and that early,
5:19
Speaker 1: they saved eight million dollars. So he was he was
5:22
Speaker 1: quite the hero for the corporate overlords, old slow money bags.
5:28
Speaker 1: Crow right. So finally the moment comes, and I can't
5:33
Speaker 1: imagine what this must have been like, but they were
5:36
Speaker 1: able to release that Colorado River that had been on hold,
5:40
Speaker 1: we'll not on hold, but flowing in a different place
5:43
Speaker 1: all those years, back into that original route. And all
5:47
Speaker 1: of a sudden you have Lake Mead, the Lake Mead Reservoir.
5:51
Speaker 1: It is um a hundred and ten miles stretching a
5:55
Speaker 1: hundred and ten miles upstream from the Hoover Dam and
5:58
Speaker 1: attracts ten million people a year two water, ski and
6:04
Speaker 1: sun and boat and do fun things. Yeah. Because again
6:07
Speaker 1: it was the designated as the nation's first national recreation area, recreation, recreation, recreation. Uh,
6:18
Speaker 1: it's the biggest reservoir in the world and um, which
6:21
Speaker 1: is saying something because there's some gigant or reservoirs out there. Yeah,
6:25
Speaker 1: this one is one point to four trillion cubic feet.
6:29
Speaker 1: They so there's so much water in their chuck that
6:32
Speaker 1: they measure it by acre feet, which is how much
6:37
Speaker 1: water it takes to flood an acre a square acre
6:40
Speaker 1: of land. And there's something like twenty eight million acre
6:45
Speaker 1: feet in in Lake Mead at its capacity. That's a
6:52
Speaker 1: lot of flooded acres. As a matter of fact, it's
6:54
Speaker 1: like twenty eight million square flooded acres of water right there.
6:59
Speaker 1: That's a lot of water. Yeah, And like me decide
7:02
Speaker 1: we should probably go over some of them, some of
7:05
Speaker 1: the stats for Hoover Damn itself, because it's it's done now.
7:10
Speaker 1: It's the um at the time was the tallest damn
7:13
Speaker 1: in the world by more than three feet um seven
7:17
Speaker 1: six ft from the canyon floor. And now it is
7:21
Speaker 1: the second tallest still the second tallest concrete gravity damn
7:26
Speaker 1: in the United States, behind the Araville Dam in California,
7:30
Speaker 1: which I don't know if you looked at that, but
7:32
Speaker 1: it's no Hoover dam Oh is it schlubby? I mean
7:36
Speaker 1: it's fine. Looks like a big giant slipping slide. It's
7:39
Speaker 1: got this huge ramp. Yeah, it's fun. But again, Bob
7:43
Speaker 1: Mule didn't write a song called the Araville Damn. Can
7:46
Speaker 1: I hear a little snippet of it? If you have
7:49
Speaker 1: no no, no, no no, just just play the first
7:52
Speaker 1: one again and I'll do this. Aura Ville's so good
8:00
Speaker 1: Today Hoover Dame is still uh second in the country
8:04
Speaker 1: in power production and ranks eleventh in the world in
8:09
Speaker 1: power production. It's second in the country still for power. Yeah,
8:13
Speaker 1: for power production. Wow, that's that's that's crazy and the
8:16
Speaker 1: biggest until nine when the Grand Coulee hydro electric Dam
8:21
Speaker 1: in the Columbia River in Washington State took it over, right, right,
8:25
Speaker 1: But so that there and there's still one and two
8:27
Speaker 1: I guess then is the thing that's right. But what's craziest,
8:30
Speaker 1: So the hydro electric power from the Hoover Dam generates
8:35
Speaker 1: like four billion kilowatt hours annually. Okay, that that must
8:41
Speaker 1: be like enough to power the entire US. That's actually
8:44
Speaker 1: not the case at all. Um, it's about I believe
8:50
Speaker 1: quarter or a five of the annual power consumption of
8:55
Speaker 1: just Los Angeles County, just Los Angeles. Um, it's about
8:59
Speaker 1: a of it, but so sure, and it is having
9:03
Speaker 1: a significant impact. I read that if they stopped producing
9:06
Speaker 1: electricity at the Hoover Dam, everyone in California and the
9:11
Speaker 1: Southwest power bills would go up by like a month.
9:16
Speaker 1: That's pretty substantial. Um, but it's it's still I'm I'm
9:20
Speaker 1: I guess I'm saying like I'm surprised it's the number
9:22
Speaker 1: two guy on the block. Still. Yeah. They the way
9:25
Speaker 1: they distribute it to is, Um, California gets about almost
9:29
Speaker 1: fifty of the power. Uh, Nevada, Nevada, they both get,
9:36
Speaker 1: and then Arizona gets about close to n Did they
9:40
Speaker 1: split that yeah, Nevada, Nevada. Yeah, Yeah, but that's only
9:45
Speaker 1: fifty three or fifty seventy three. That's still not I
9:49
Speaker 1: wonder where if the rest where the rest goes downstream
9:54
Speaker 1: the power? Yeah, well no, always so you're talking about
9:57
Speaker 1: the power of the water. The power. Oh, I don't know,
10:00
Speaker 1: because I wonder how much of that operates the damn itself.
10:05
Speaker 1: Can't be that much. I mean, that's a lot left over.
10:08
Speaker 1: I'm not sure. Yeah, I'm not really sure. So, um,
10:11
Speaker 1: regardless of where that that phantom electricity goest Chuck, I
10:14
Speaker 1: want to talk about another extraordinarily foresightful um part of
10:20
Speaker 1: this project. Do you remember when they diverted the river
10:24
Speaker 1: in those four tunnels around the damn project site? What
10:29
Speaker 1: what are you talking about? Well, let's go back. Well,
10:32
Speaker 1: we'll go back and replay the entire episode real quick,
10:35
Speaker 1: and they'll be in there somewhere. So, so they diverted
10:39
Speaker 1: the river so they could build the dam, and they
10:41
Speaker 1: saved those those tunnels. They didn't just like cover them
10:45
Speaker 1: up and say forget you, we don't need you anymore.
10:47
Speaker 1: They said, no, no, no, we can actually use you
10:49
Speaker 1: in the future. So one on each side is now
10:53
Speaker 1: called the penn stock. It's a it's they they've been
10:56
Speaker 1: um encased in steel and then um narrow rowed from
11:00
Speaker 1: fifty ft to thirty ft in diameter, which is still
11:03
Speaker 1: pretty substantial, and they use those to send water from
11:08
Speaker 1: the lake mead to the power station turbines on either side,
11:13
Speaker 1: the Nevada side and the Arizona side, and that's where
11:15
Speaker 1: the hydroelectric power is is generated. So they use the
11:19
Speaker 1: diversion tunnels to generate the hydroelectric power. Now, yeah, it's
11:23
Speaker 1: amazing the water falls into these things. Uh go down
11:28
Speaker 1: about five feet into this power station, which, by the way,
11:31
Speaker 1: part of the tour is you get to go down
11:33
Speaker 1: into the bowels. We miss that, which is kind of neat. Um. Yeah,
11:39
Speaker 1: you didn't about the word bowels just turned you off,
11:41
Speaker 1: So that's why did um. So it falls about five
11:45
Speaker 1: feet into the power station. Uh, it's flowing here at
11:48
Speaker 1: about two thousand cubic feet between two and three thousand
11:52
Speaker 1: cubic feet per second, And anyone who knows what hydro
11:56
Speaker 1: electric power means, all you're doing is using that water
11:59
Speaker 1: to spin turbine and connect that to a power generator
12:03
Speaker 1: and all of a sudden, Arizona, Nevada, and California are
12:07
Speaker 1: getting juice, right, which is pretty ingenious because if you
12:10
Speaker 1: think about it, when when that water is flowing from
12:14
Speaker 1: Lake me down these um these pen stocks to the turbines,
12:20
Speaker 1: they're not using any pumps or anything like that. It's
12:22
Speaker 1: all just gravity um sending it over like a six
12:26
Speaker 1: hundred feet drop and what did you say? It was
12:28
Speaker 1: like two thousand to three thousand cubic feet per second,
12:34
Speaker 1: So that chuck is a lot of water. That is
12:37
Speaker 1: a tremendous amount of water, so much so that converted
12:41
Speaker 1: into big Max per second. You're talking eighty nine thousand,
12:45
Speaker 1: three hundred and sixty seven big Max per second if
12:48
Speaker 1: you're moving water to two thousand cubic feet per second.
12:52
Speaker 1: And that's actually accurate based on the dimensions of big
12:55
Speaker 1: MACA did the calculation. That's how many big Max would
12:58
Speaker 1: be flying past you in a second if if it
13:01
Speaker 1: were big Max instead of water they were sending down
13:04
Speaker 1: there the other stat which staggers me and uh, because
13:07
Speaker 1: I was thinking, like, there's no way Julia actually figured
13:11
Speaker 1: out the horse power of this whole thing, and she
13:15
Speaker 1: did well, she found someone who did, and this thing
13:19
Speaker 1: can crank out almost three million horsepower combined. I know
13:29
Speaker 1: that's a lot of horse power, but I'm just trying
13:30
Speaker 1: to like put it in other terms, like how many
13:33
Speaker 1: how many trains is that We'll just think about standing uh,
13:38
Speaker 1: in the middle of a desert and seeing three million
13:40
Speaker 1: horses charging at you. It's a lot of horsepower. That's
13:43
Speaker 1: a lot of horses. It is so the way that
13:47
Speaker 1: the water gets from Lake Mead down to the turbines,
13:52
Speaker 1: I mean, it's all very much control. And the way
13:53
Speaker 1: they control it is if you ever go to the
13:56
Speaker 1: Hoover Dam, just on the Lake Mead side of the dam,
13:59
Speaker 1: there these four towers that rise out of the water,
14:02
Speaker 1: and those towers have gates that can be opened and
14:06
Speaker 1: closed to let water in. And those are the gates
14:09
Speaker 1: that let the water and that send it to the
14:11
Speaker 1: pen socks down in into to power the turbines and
14:15
Speaker 1: the power stations, apparently to the tune of three million
14:18
Speaker 1: horse power. It is amazing. Again, all of this if
14:22
Speaker 1: you step back and just kind of look at it
14:23
Speaker 1: as a kid, you're like, yeah, put a hole here
14:26
Speaker 1: to make the water go there, to make the turbine spin.
14:29
Speaker 1: It's really simple in a lot of ways. But the
14:32
Speaker 1: amount of ingenuousness it took to actually execute it, that's
14:36
Speaker 1: where the chef's kiss lines. All right, let's take a
14:41
Speaker 1: break here and uh, we're gonna come back and talk
14:44
Speaker 1: about uh spill ways right after this. Alright, chuck. So
15:19
Speaker 1: they used two of the four diversion tunnels to feed
15:23
Speaker 1: the turbines to generate hydroelectric power that leaves to other ones.
15:28
Speaker 1: And I know they didn't just forget about those what
15:31
Speaker 1: are they using those four? And this is sort of
15:35
Speaker 1: the final component here, because what they had to do was, Um,
15:39
Speaker 1: I mean, when this thing is working great, which it
15:41
Speaker 1: almost always has, we'll get to that in a second. Um,
15:44
Speaker 1: everything's awesome. People are getting power, people are waterskiing on
15:47
Speaker 1: Lake Mead. Um, people are getting water, Crops are getting water,
15:52
Speaker 1: cows are drinking water. Everybody's happy. But they did have
15:55
Speaker 1: to think about the fact that the Colorado River used
15:58
Speaker 1: to be quite a bear and may get angry again
16:00
Speaker 1: one day, or this thing may fail one day. So
16:04
Speaker 1: we need to think about what happens if something does
16:06
Speaker 1: go wrong, whether it's a flood or the system breaks
16:09
Speaker 1: down or something. So they thought ahead and they they
16:13
Speaker 1: set up what we're called spill ways. They can actually
16:16
Speaker 1: divert once again, all that water into those two outer tunnels,
16:22
Speaker 1: uh that are now referred to as spill ways. But
16:25
Speaker 1: this is downstream, right right, so not the upstream tunnels
16:30
Speaker 1: that are being used UH for the flibbertyg of its.
16:33
Speaker 1: Have you ever seen a fish ladder? Surely you have, Yeah,
16:37
Speaker 1: we've I think we've even talked about them on something before. Yeah.
16:41
Speaker 1: That's basically like an upstream spill way. Yeah, okay, So
16:45
Speaker 1: this is the opposite that's sending it down, and it's
16:47
Speaker 1: it's it's the exact same principle and almost the exact
16:50
Speaker 1: same design as that little overflow hole that you have
16:53
Speaker 1: in your sink. So like you you can't flood your
16:57
Speaker 1: bathroom because eventually, if that water or level hits that hole,
17:01
Speaker 1: it's just going to go into the hole and down
17:03
Speaker 1: the drain. Anyway, this is the exact same thing. So
17:06
Speaker 1: they utilize those remaining two um diversion tunnels as the spillways,
17:12
Speaker 1: and they didn't lower them at all. Remember they reduced
17:15
Speaker 1: the other ones to like thirty ft from fifty ft.
17:18
Speaker 1: These are still fifty ft spill ways lined with like
17:20
Speaker 1: three ft of concrete. But they follow very similar trajectories
17:25
Speaker 1: where you know, the water hits a certain level on
17:27
Speaker 1: like a flood or whatever, and it goes through these
17:30
Speaker 1: spill ways and then it drops several hundred feet I
17:33
Speaker 1: think six hundred feet, which is a lot for a
17:36
Speaker 1: lot of water to drop. It starts to pick up
17:38
Speaker 1: a pretty pretty high velocity, and then it it all
17:42
Speaker 1: spills out of these gates a little further downstream beyond
17:46
Speaker 1: the hydroelectric plants, and everybody's saved and happy and nothing. No,
17:51
Speaker 1: no waters ever meant to go over the top of
17:54
Speaker 1: the Hoover Dam. If that ever happened, that would be
17:57
Speaker 1: colossally bad. It's never designed to do that. Um, it
18:01
Speaker 1: probably never will do that. Even if humans suddenly just
18:05
Speaker 1: vanish overnight, the spillways would probably still work. But um,
18:10
Speaker 1: that's what it's designed for. Is designed to just get
18:12
Speaker 1: rid of that water and reroute it, basically like they
18:16
Speaker 1: rerouted the Colorado River, but this time they're rerouting it
18:18
Speaker 1: around the power stations which would be swamped with that
18:21
Speaker 1: much water. Yeah, and they don't let it's it's not
18:23
Speaker 1: like they were like, all right, if this gets within
18:25
Speaker 1: like three or four feet, we're gonna take action. If
18:28
Speaker 1: it gets to within they said it at twenty seven feet.
18:31
Speaker 1: So if the water rises for any reason to within
18:34
Speaker 1: that twenty seven feet to the top of where those
18:38
Speaker 1: cards are driving, the spillway gates open up, uh, and
18:42
Speaker 1: it diverts that water and the dam uh is not
18:46
Speaker 1: able to breach, which like you said, would be catastrophic.
18:49
Speaker 1: It let's out a big huray uh. And the good
18:52
Speaker 1: news is the system, that outlet system has never failed
18:56
Speaker 1: uh and it's only had to be used twice once
18:59
Speaker 1: for the test in one and then in nineteen eighty three.
19:04
Speaker 1: It was actually a flood that got within that caused
19:07
Speaker 1: that river to go up within twenty seven feet and
19:10
Speaker 1: they opened up that spillway, which I imagine there was
19:14
Speaker 1: I mean, it was probably kind of scary, but they
19:16
Speaker 1: were probably some engineers that were pretty excited to get
19:18
Speaker 1: to use those spillways finally, Yeah, because they I mean,
19:21
Speaker 1: you would have had to have been an old time
19:23
Speaker 1: or to have been there for the nineteen forty one
19:25
Speaker 1: test by the time three came around. So I'm sure
19:28
Speaker 1: all these people wanted to see this because they they
19:31
Speaker 1: had never seen it work before, and they also wanted
19:33
Speaker 1: to know if it did work. And it definitely worked.
19:36
Speaker 1: I mean it was it wasn't a drill like one.
19:39
Speaker 1: It was a straight up flood like this is what
19:41
Speaker 1: it was designed for, and it worked just fine. Yeah.
19:43
Speaker 1: But both times during the test and during that flood,
19:47
Speaker 1: those spill ways suffered some some damage. So let's talk
19:50
Speaker 1: about the um the failures that have happened over the years. Right.
19:55
Speaker 1: So in those those first few years, when everyone was
19:58
Speaker 1: still kind of biting their nails a little bit, there
20:00
Speaker 1: were there were a couple of problems. Um Air bubbles
20:03
Speaker 1: formed in these spill ways and seepage, like water started
20:07
Speaker 1: seeping under the base of the dam, which is not
20:10
Speaker 1: good at all. No, and those are actually two different things,
20:14
Speaker 1: so both we'll start with the the um air bubbles, right.
20:19
Speaker 1: So that's that's called cavitation. And when the spill ways
20:22
Speaker 1: were used, both in that ninety one test and in
20:25
Speaker 1: the actual flood, when that water, that huge, huge amounts
20:30
Speaker 1: of water fell, you know, six hundred feet down to
20:34
Speaker 1: the elbow of the spill way that led it the
20:36
Speaker 1: rest of the way out to the river um when
20:40
Speaker 1: it hit, when it impacted. By that time, these things
20:45
Speaker 1: called cavitations, a little like bubbles of vapor had formed
20:51
Speaker 1: in the water column. And these things were so strong
20:54
Speaker 1: that when they collapsed they had enough force that they
20:57
Speaker 1: could like shatter concrete. So when this the spill test
21:01
Speaker 1: was done, the spell way test, and then when the
21:02
Speaker 1: flood was over, and the spell ways were turned off.
21:05
Speaker 1: They went and investigated. There were huge chunks of concrete missing.
21:08
Speaker 1: The water had just sheared it away like it was nothing.
21:11
Speaker 1: And the cavitation is still not really fully understood. It's
21:15
Speaker 1: part of like a really um infrequent unusual occurrence like that,
21:20
Speaker 1: like water typically doesn't flow that fast on Earth over
21:24
Speaker 1: you know, a man made structure, so it's not like
21:26
Speaker 1: something we have to worry about. But they figured out
21:28
Speaker 1: that if you insert aer raiders or air ducts something
21:32
Speaker 1: to insert air into that water to kind of lessen
21:36
Speaker 1: the blow kind of pad or pillow the the impact
21:40
Speaker 1: of those cavitations collapsing, it can protect concrete. And so
21:45
Speaker 1: after one they didn't really know what they were doing
21:48
Speaker 1: after somebody had figured out aeration by that time, and
21:52
Speaker 1: so they installed them right afterwards. And as far as
21:54
Speaker 1: I know, they haven't tested it to see if it works,
21:57
Speaker 1: but in other places it's been shown to work, so
21:59
Speaker 1: I think gets a pretty safe bat that if those
22:02
Speaker 1: overflow spill ways have to be used again, they probably
22:05
Speaker 1: won't cavitate because of the aeration that was inserted into
22:09
Speaker 1: the spill ways. Now, yeah, well, I actually saw in
22:12
Speaker 1: forty one they knew that they could do this with
22:14
Speaker 1: air ducks, but the government wouldn't pony up for the money.
22:17
Speaker 1: Oh is there right, Yeah, they denied the funds. And
22:20
Speaker 1: uh it took until that flood of eighty three when
22:23
Speaker 1: it happened again, when the government was like, all right,
22:26
Speaker 1: we'll pay for this stuff. Fine, Hoover's ghost came out
22:32
Speaker 1: for the don't get involved. It's not the government's job
22:36
Speaker 1: to pay for broken concrete. So, um, this seepage was
22:40
Speaker 1: the other was the other sort of engineering failure, and
22:43
Speaker 1: we should, you know, we need to point out that
22:45
Speaker 1: this thing is performed really, really well, Like none of
22:48
Speaker 1: these failures broke the damn. You know, that's a really
22:51
Speaker 1: good point, and I think it's definitely worth pointing out.
22:53
Speaker 1: Like the spill waves those were huge you know where
22:57
Speaker 1: where and tear that that probably shouldn't have happened in
23:00
Speaker 1: probably won't again. But yeah, the whole system still worked. Yeah.
23:03
Speaker 1: So if you have a damn like this, Um, the
23:06
Speaker 1: stability of this whole thing relies on keeping all that
23:11
Speaker 1: water out. So any seepage under the base of that
23:14
Speaker 1: damn is not good. It's gonna cause uplift pressure that's
23:18
Speaker 1: gonna shift the whole foundation, and this grout uh basically
23:23
Speaker 1: was was failing. Um, a grout curtain is going to
23:26
Speaker 1: prevent the seepage. So they were pressure injecting all this
23:29
Speaker 1: grout into these holes trying to fill cavities, but it, uh,
23:34
Speaker 1: it was not and they were getting some seepage in there. Well,
23:38
Speaker 1: they did a really poor job of geological exploration before
23:43
Speaker 1: they ever started the project. Yeah, that was the main
23:45
Speaker 1: issue there. So, like the same grout that they they
23:49
Speaker 1: introduced into those cooling pipes after they were finished building
23:52
Speaker 1: the actual damn itself, they were they were introducing that
23:56
Speaker 1: into these holes they drilled to kind of fill those cracks, crevices, faults,
24:00
Speaker 1: all this stuff that's in the bedrock. Because normally, when
24:03
Speaker 1: the Colorado rivers flowing chuck, it's like it's fine, it's
24:06
Speaker 1: allowed to keep going and it doesn't try to get
24:08
Speaker 1: anywhere aside from the river bed. But when it runs
24:12
Speaker 1: into the dam, then it's got issues. The water wants
24:15
Speaker 1: to go somewhere, right, Yeah, that's what water does. It
24:18
Speaker 1: wants to go somewhere, So it starts to find those
24:20
Speaker 1: little cracks and crevices and faults, and when it fills
24:24
Speaker 1: up enough of them, it can actually lift up the dam,
24:27
Speaker 1: and that's what it was doing, it was lifting up
24:29
Speaker 1: the dam. So they went back and drilled more holes
24:32
Speaker 1: and added even more grout and basically created this barrier.
24:36
Speaker 1: So you've got the barrier that's the dam, and then
24:39
Speaker 1: you have the barrier that's this grout reinforced bedrock, you know,
24:44
Speaker 1: hundreds of feet down into the earth. So now the
24:47
Speaker 1: water just gives up and does what it's told. Yeah,
24:49
Speaker 1: I love that they they really went overboard there and
24:53
Speaker 1: like an additional three feet underground with this grout. But
24:58
Speaker 1: imagine being like the dam is actually lifting up, it's
25:03
Speaker 1: starting to float. That is the exact opposite of what
25:06
Speaker 1: you want to go on with your damn. Yeah, for sure,
25:09
Speaker 1: because apparently on the on the face of the damn,
25:13
Speaker 1: the um upstream face, the water pressing up against it
25:17
Speaker 1: like meat, is over a hundred miles long. It's an
25:20
Speaker 1: enormous amount of water and it's being held back by
25:23
Speaker 1: this one slab of concrete. And I guess I think
25:27
Speaker 1: Julius said it was like forty five thousand pounds per
25:31
Speaker 1: square feet of pressure pressing up against the damn at
25:34
Speaker 1: all times. So yeah, that that um that's a that's
25:38
Speaker 1: just Harry if you think about it, especially then if
25:41
Speaker 1: you start to think about the that amount of that
25:44
Speaker 1: amount of concrete like being lifted up by the water
25:47
Speaker 1: and it's just basically being moved out of the way,
25:50
Speaker 1: and they had to stop it in time. Alright, folks,
25:53
Speaker 1: we're gonna take our last break. We're gonna come back
25:55
Speaker 1: and finish up with part four, Part two of Hoover
26:00
Speaker 1: Damn right after this. All right, we're gonna bring it
26:34
Speaker 1: home here with um or or we could keep talking
26:38
Speaker 1: about it forever, uh, with a little bit on how
26:42
Speaker 1: um the Hoover Damn just really changed the United States
26:45
Speaker 1: and especially the Southwest. UM Roosevelt Franklin Roosevelt dedicated the
26:50
Speaker 1: damn on sept and man insult to injury. Former President
26:57
Speaker 1: Herbert Hoover was not even on the guests list to
27:00
Speaker 1: come from and see that dedication. No, do you mene
27:04
Speaker 1: like four years after and he was the guy who
27:07
Speaker 1: was the first champion of the whole thing too, I
27:09
Speaker 1: mean like it was his project for sure. So uh,
27:13
Speaker 1: that area, that region, it really changed everything, um aside
27:17
Speaker 1: from Boulder City becoming a real place, which is kind
27:20
Speaker 1: of neat in Vegas growing. The whole region was allowed
27:24
Speaker 1: to flourish, um because well one big reason it's because
27:28
Speaker 1: they tamed that Colorado River. No more flooding, right, Um,
27:34
Speaker 1: So no more flooding meant that you could actually have
27:36
Speaker 1: like a stable agricultural um industry, right yeah the area.
27:42
Speaker 1: It says here the region's crops and livestock account for
27:46
Speaker 1: and of the entire country's production. Yeah, and they grow
27:50
Speaker 1: so much like lettuce and cilancho and stuff that that
27:53
Speaker 1: regions now called America's salad bowl. Um. It's a huge, like,
27:57
Speaker 1: it has enormous amounts of production, and it never would
28:00
Speaker 1: have gotten to that that point had the Hoover damn
28:04
Speaker 1: not produced like a steady, reliable supply of irrigation and
28:08
Speaker 1: um done away with flooding. Like there's no more. There
28:11
Speaker 1: hasn't been a single flood from the Colorado River that's
28:14
Speaker 1: affected any of the land in the area since the
28:17
Speaker 1: Hoover Dam came online. You know, when I lived in
28:19
Speaker 1: Yuma and I waited tables at Julianna's patio cafe, there
28:24
Speaker 1: was this this dude, I can't remember his name, but
28:28
Speaker 1: this one guy that would bring in a bunch of
28:30
Speaker 1: big money guys uh to eat every now and then,
28:34
Speaker 1: like six or eight of them for these business dinners.
28:37
Speaker 1: And he was a lettuce guy. Oh yeah, okay, And
28:40
Speaker 1: I just thought it was so funny growing up in
28:42
Speaker 1: Atlanta and never you know, thought about it. But he
28:44
Speaker 1: all he did was grow let us in. If he
28:47
Speaker 1: came in with his you know, six or eight buddies,
28:50
Speaker 1: like you had to shut down and take that table
28:53
Speaker 1: only like he expected you to only wait on your
28:56
Speaker 1: table right. Well, there's some real lettuce in it for you,
29:00
Speaker 1: Oh there was. It was he a good tipper because
29:03
Speaker 1: a lot of times those guys are not well. It
29:05
Speaker 1: was he always had a party big enough to where
29:07
Speaker 1: the tip was included. Um. And he would usually give
29:10
Speaker 1: you give you a little lettuce on top of that.
29:13
Speaker 1: That's nice. Literally, here's a piece of romaine for you.
29:17
Speaker 1: It's good for you, kid, and spank you on the
29:20
Speaker 1: bottom as you were walking away down. Um. So the
29:24
Speaker 1: Hoover Dam changed everything, like Uh, places like Tucson, Arizona
29:28
Speaker 1: would not even have been allowed to happen. Uh in
29:31
Speaker 1: Las Vegas and l A booming like it did, um
29:35
Speaker 1: thanks to the Hoover Dam. Like you said, no flooding
29:38
Speaker 1: tons of production and everything is under control. One thing
29:42
Speaker 1: they did have to worry about, well, we'll talk about
29:46
Speaker 1: what they are worrying about now in a minute. But
29:48
Speaker 1: one thing they did worry about then and then, like
29:51
Speaker 1: in World War two and again at nine eleven, was
29:54
Speaker 1: the fact that it's a terror target because it so
29:57
Speaker 1: many places rely on this for water, the irrigation. That
30:01
Speaker 1: if terrorist organization took out the Hoover Dam especially I
30:06
Speaker 1: mean to be bad anytime, but especially in World War two,
30:08
Speaker 1: it would have been catastrophic. Yeah, so I guess nineteen
30:12
Speaker 1: thirty nine, the Mexican government let the American embassy in
30:16
Speaker 1: Mexico City know, hey, we just heard that the Germans
30:19
Speaker 1: are planning on bombing Hoover Dam, and UM America was
30:23
Speaker 1: like what, And they put up all these new safeguards
30:27
Speaker 1: and got military police to patrol the area. They installed
30:30
Speaker 1: floodlights on Lake Mead, they put up a steel net
30:34
Speaker 1: so you couldn't get anywhere near the um, anywhere near
30:37
Speaker 1: the dam on the Lake Mead side because remember, I mean,
30:40
Speaker 1: people are like boating and recreating on this um. So
30:43
Speaker 1: they had to kind of keep people away from the
30:45
Speaker 1: damn for the first time. And but they still kept
30:48
Speaker 1: going on. You could still go visit and everything, and
30:50
Speaker 1: then Pearl Harbor happened. Um, and they were like damns
30:53
Speaker 1: closed and they closed the damn to the public for
30:57
Speaker 1: the duration of the war, I think until like the
30:59
Speaker 1: end of ninety five they finally opened it to the
31:01
Speaker 1: public again. All because of the dirty Nazis. Yeah, man,
31:05
Speaker 1: and they um they did. The damn itself actually had
31:08
Speaker 1: its own police force. Um. The Army of course came
31:11
Speaker 1: in there to help out as well. But it was
31:14
Speaker 1: a pretty big deal because not only are you disrupting
31:17
Speaker 1: water and maybe flooding the valley, but the power supply
31:22
Speaker 1: to southern California. There was a lot of aviation manu
31:25
Speaker 1: still is a lot of aviation manufacturing in Southern California
31:29
Speaker 1: and for and I think that's what the Nazis were
31:31
Speaker 1: really after, to disrupt the power supply to the aviation industry. Yeah,
31:37
Speaker 1: because at the time America wasn't even in World War
31:39
Speaker 1: Two yet, but we were helping the British with the
31:42
Speaker 1: aviation stuff we were building. So they were trying to
31:45
Speaker 1: strike at the heart of British capabilities by blowing up
31:48
Speaker 1: the Hoover Dam. There, unexpected the Nazis want to blow
31:52
Speaker 1: up the Hoover dam and the US is like, what
31:54
Speaker 1: did we do? We're not even in this so called
31:57
Speaker 1: World war, right, Oh yeah, helping them? It's all right,
32:00
Speaker 1: I got you. We're still not going to let you
32:02
Speaker 1: do it, but now we understand. Uh. And then, of
32:05
Speaker 1: course after nine eleven it was, um, there was a
32:08
Speaker 1: lot of fear that that could be a potential and
32:11
Speaker 1: it still limbs as a potential terrorist target. Well that
32:14
Speaker 1: was one reason why they built the bridge, the bypass bridge,
32:17
Speaker 1: was They're like, you know, this is just too vulnerable
32:20
Speaker 1: letting people drive over it. And so from what I understand,
32:24
Speaker 1: either after um the German bomb plot became evident or
32:29
Speaker 1: after nine eleven, and I think it was after nine
32:31
Speaker 1: eleven until that bridge opened up, when you drove over
32:35
Speaker 1: the Hoover damn you had to wait and it would
32:38
Speaker 1: happen and I guess shifts, and you would be escorted
32:42
Speaker 1: across by the police um in groups of cars, and
32:46
Speaker 1: then you'd be you'd make your way to the other
32:48
Speaker 1: side and they'd be like keep going, don't even look back,
32:50
Speaker 1: or we'll arrest you. Um. And then that's how you
32:52
Speaker 1: got across until they finally opened the bypass, which must
32:56
Speaker 1: have been um up, but there are a lot of delays. Yeah,
33:00
Speaker 1: probably so in that situation. So the current threat, aside
33:05
Speaker 1: from that looming terror threat, is the fact that, uh,
33:09
Speaker 1: there have been about sixteen years of drought in that area,
33:14
Speaker 1: and uh it's scary. Man. Lake meat is not the same.
33:20
Speaker 1: I mean it is what it like a hundred and
33:22
Speaker 1: fifty feet uh lower than it used to be then
33:26
Speaker 1: it wasn't two thousand and thirty feet. I mean that's amaze.
33:29
Speaker 1: That's a huge, huge drop. Yeah, there's like a bathtub
33:32
Speaker 1: ring high water mark. Now it's just the discoloration along
33:37
Speaker 1: the canyon walls where you can see where it used
33:39
Speaker 1: to be, and it's really significant. And the problem is
33:42
Speaker 1: when they built the dam, they built it so that
33:46
Speaker 1: the the gates that um allow water down to the
33:51
Speaker 1: pen socks to the hydro electric plant they cut off
33:54
Speaker 1: at a certain height. After that the water is too
33:58
Speaker 1: low to flow through the gates, and in you have
34:00
Speaker 1: no hydro electric power. Same thing with the pipes that
34:04
Speaker 1: pump water out to Las Vegas and Los Angeles and
34:08
Speaker 1: Tucson and everywhere else that gets water. Um, they're at
34:11
Speaker 1: a certain height too, so once they I think, once
34:14
Speaker 1: the water level hits like eight ft, there's no more
34:18
Speaker 1: water that can be drawn out. And they actually got
34:20
Speaker 1: around this by creating a new low level pumping system
34:26
Speaker 1: to where they came in and went under the under
34:30
Speaker 1: Lake Mead and tapped into it and now just like
34:34
Speaker 1: a bathtub drain at the bottom of a bathtub, there's
34:37
Speaker 1: a pumping station so that that now they're not like, Okay,
34:40
Speaker 1: we have eight water we can't get to to drink
34:44
Speaker 1: from any longer. Now they're like, no, we can. We
34:46
Speaker 1: can get to all the water we need to for
34:49
Speaker 1: um for drinking, which is a huge relief. That's a big,
34:53
Speaker 1: big deal that they were able to do this. But
34:55
Speaker 1: at the same time, everyone's still very much aware that
34:59
Speaker 1: they're like, we still have issues, like we're losing water
35:02
Speaker 1: through evaporation and from um, you know, lower and lower
35:07
Speaker 1: snow accumulations up in the Rockies where all this water
35:09
Speaker 1: comes from in the first place. Like there's a big
35:12
Speaker 1: problem with climate change and it's having an enormous impact
35:15
Speaker 1: on Lake Mead, and because all these areas you know,
35:17
Speaker 1: depend on it for electricity and water, everybody's really freaked
35:21
Speaker 1: out right now, Yeah, so the the current proposition is
35:24
Speaker 1: the l A Department of Water and Power. Um, they
35:28
Speaker 1: have something on the table that it's basically like a loop,
35:32
Speaker 1: a cycled loop system. They said, why don't we do
35:34
Speaker 1: a return path for that water. Put a huge pump station,
35:38
Speaker 1: solar powered pump station downstream that's gonna then send water
35:42
Speaker 1: and cycle it back up to the reservoir. And not
35:46
Speaker 1: only that, I mean it's a pretty good idea. Um.
35:48
Speaker 1: Not only that, it would you could still you know,
35:50
Speaker 1: you could enable more power generation and also create a
35:54
Speaker 1: reserve of electricity for peak periods. So then all of
35:58
Speaker 1: a sudden, the Hoover Dam is like a big battery
36:01
Speaker 1: essentially run by uh, solar power, right, which sounds great.
36:06
Speaker 1: It's like, okay, yeah, why why just let all that
36:08
Speaker 1: water go when you're just generating hydroelectricity from it? You know,
36:12
Speaker 1: put it back. But all the people who depend on
36:15
Speaker 1: that water down stream say, uh, we still need that water.
36:19
Speaker 1: You can't pump it back into Lake Mead. We need
36:21
Speaker 1: that stuff like that's our water. Um. And that's part
36:25
Speaker 1: of the problem with it, Chuck, is that there's so
36:27
Speaker 1: many people who depend on this, not just from Hoover Dam,
36:32
Speaker 1: but there's like multiple damns above Hoover Dam too. So
36:37
Speaker 1: there's a lot of people drawing water for all sorts
36:39
Speaker 1: of different purposes. Um, from the Colorado River. That there's
36:44
Speaker 1: just it seems to be too many. There's just too
36:46
Speaker 1: many people. There's too many, there's too much need. And
36:49
Speaker 1: when you toss in climate change, uh and the impact
36:53
Speaker 1: that the sixteen or nineteen your drought is having, it's, um,
36:56
Speaker 1: it's it's it's a really precarious position right now that
36:59
Speaker 1: they have not figured out. Yeah, pretty scary, man, it
37:02
Speaker 1: is scary for sure. I got nothing else that is
37:06
Speaker 1: surprising because there is a lot to talk about. I've
37:09
Speaker 1: got one more thing. So you said that, um that
37:12
Speaker 1: uh FDR dedicated the place in right? Is that what
37:18
Speaker 1: I said? I believe that's what you said. Everybody, Yeah,
37:21
Speaker 1: that's what you said. So. Um. There is a sculptor
37:26
Speaker 1: named Oscar J. W. Hanton And you know the the
37:31
Speaker 1: winged Art Deco giant figures the statues that are there
37:35
Speaker 1: on site. So he created those. And did you notice
37:38
Speaker 1: the Toronto floor the apron that's in front of those statues.
37:43
Speaker 1: I don't remember. It's okay. So there are these two
37:46
Speaker 1: giant art deco statues. They look kind of like the
37:48
Speaker 1: Oscar Award, but with wings and they're seated and um.
37:52
Speaker 1: They're there to just basically commemorate this conquering of humanity
37:56
Speaker 1: over you know nature. Um. But on the round in
38:00
Speaker 1: Toronto is a star map and it shows the exact
38:04
Speaker 1: position of the stars in the sky on that day
38:08
Speaker 1: in when Hoover Dam was dedicated, So that future generations
38:13
Speaker 1: to come, even if there's like no more Americans and
38:16
Speaker 1: no one speaks English anymore, and this whole area has
38:18
Speaker 1: been abandoned, they could come back and find the Hoover
38:21
Speaker 1: Dam and the star map and calculate the exact day
38:24
Speaker 1: that it was dedicated, just based on the position of
38:26
Speaker 1: the stars and this Toronto floor and that neat. That's amazing,
38:32
Speaker 1: extra little touch there. Learn that on the self guided tour.
38:34
Speaker 1: By the way, yep, if you want to know more
38:39
Speaker 1: about the Hoover Dam, go go to the Hoover Dam.
38:42
Speaker 1: We can talk about it all day long. We could
38:43
Speaker 1: talk about it for two more episodes and it still
38:46
Speaker 1: wouldn't get across what it's like to be there. Uh.
38:48
Speaker 1: And since I said that it's time for listener mail,
38:55
Speaker 1: I'm gonna call this. Uh uh, Well, we got something
38:59
Speaker 1: wrong in deserts or Rival, which, by the way, we
39:02
Speaker 1: got a lot of kudos that that perhaps maybe our
39:04
Speaker 1: funniest episode. That was great. It was a lot of fun. Yeah,
39:07
Speaker 1: we're being silly that day. Those are always good. Hey, guys,
39:11
Speaker 1: been an ABBOD listener for years. Can't thank you enough
39:13
Speaker 1: for the countless hours of entertainment. Despite all the great
39:16
Speaker 1: topics and education, I've never been tempted to write until today.
39:19
Speaker 1: During your Desert Survival opening an immediate and hilariously enjoyable
39:24
Speaker 1: left turn tangent Chuck, you mentioned your tribute to Annie
39:28
Speaker 1: with a reference to food Glorious Food. I feel so dumb.
39:33
Speaker 1: That song is actually from Oliver, which I know. I
39:37
Speaker 1: know that everybody knows. You know that I know Annie
39:40
Speaker 1: and I know Oliver. Maybe they were friends. Could I
39:44
Speaker 1: have school, please, Daddy war books? That's it. That's the
39:49
Speaker 1: big line, um, he said. I thought you might get
39:51
Speaker 1: a kick out of how I know this to be true.
39:53
Speaker 1: When I was about eight or nine, my hometown did
39:55
Speaker 1: a community production of Oliver and I was cast. What
39:59
Speaker 1: part did you play? You may ask, Well, in the
40:02
Speaker 1: song food Glorious Food, there's a line that goes food,
40:05
Speaker 1: glorious food, peas puddings, and save lois. What next is
40:11
Speaker 1: the question, rich gentleman, habit boys indigestion. At the singing
40:16
Speaker 1: of Indigestion, my role and shining moment of the performance
40:19
Speaker 1: was to lean over while the tuba and the orchestra
40:22
Speaker 1: pit let out a deep and juicy note. Yes that's
40:25
Speaker 1: right everyone. I was in the credits as the flatulent orphan.
40:30
Speaker 1: See you get that he bends over in the tuba
40:32
Speaker 1: goes uh got it. Needless to say, guys, my life
40:36
Speaker 1: peaked early. I will always be remembered for that song.
40:39
Speaker 1: Thanks for all you do. That is Eddie in Denver, Colorado. Eddie,
40:43
Speaker 1: that was a fantastic listener mail, good one, like a
40:46
Speaker 1: award winning maybe, ye man, I mean, if you're talking
40:50
Speaker 1: tuba farts, you've got my heart. Yeah you. Eddie just
40:53
Speaker 1: got the Hoover Damn Award for listener Mails, the current
40:58
Speaker 1: Hoover Damn Award older. So thanks for that good one.
41:02
Speaker 1: If you want to get in touch with us, you
41:05
Speaker 1: can go to stuff you Should Know dot com. All
41:08
Speaker 1: of our social links are on there, or you can
41:10
Speaker 1: just send us an email. Send it off to Stuff
41:13
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41:20
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41:23
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41:28
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