How Quicksand Causes Dam Failures

In civil engineering, quicksand is more than just a puddle of mud! The "quick condition" occurs when seepage reduces the effective stress of a soil. This can lead to some dangerous conditions, especially if the seepage causes piping erosion to occur at a dam. Thanks for watching!
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[@jsal7666]

This video is so good, *soil* subscribe to your channel.

[@clonewarrior1999]

J Sal What?

[@AnthonyRagus]

J Sal ಠ_ಠ

[@catcrisst5277]

"So i'll

[@MajesticDemonLord]

Wow. You really had to dig deep for that pun.

[@cuppa.j0o]

J Sal i’m soilscribing to you

[@ThisOldTony]

i blame science (& you by extension) for the lack of quicksand plot devices in today's television programming.

[@PracticalEngineeringChannel]

My life's greatest achievement

[@Bird_Dog00]

Ah, Hollywood quicksand. aka, how an object that floats on water just fine, suddenly sinks in a fluid much denser than water... The only people whom I would expect to sink in quicksand are screenwriters and producers...

[@HPD1171]

there are still tar pits which have the benefit of not only trapping you from being able to move but you also sink since tar like most petroleum based compounds is less dense then water so animals being made mostly of water simply sink while not being able to move to get out. I am not sure why they aren't used as lot devices more often as they are truly terrifying and ARE a death sentence if you have no help to get out. thought there is the problem that they are too viscous to be used in movies as the movement is so slow that you would need a scene that is several hours or even a couple days depending on the viscosity to get the point across so not the most practical.

[@EebstertheGreat]

@@HPD1171 As far as I am aware, there is no record of a human ever getting stuck and dying in a tar pit. The remains of a single ancient woman were found in the La Brea tar pits, but it is believed that she was buried intentionally. They seem to pose a much greater threat to quadrupeds.

[@kvakerbillduck9500]

Indy 4 was not good for you? But i must admit princes bride is way way better

[@RealEngineering]

Fascinating stuff. Could see myself getting into soil mechanics

[@saitenotoshuitsnaini]

Wait. How could the seepage water possibly goes up?

[@syntheovaldy5173]

@@guyfriends1843 ???

[@zombieregime]

It is a deep subject, but the basics can be compressed into a manageable size. This video just scratches the surface, the subject can expand layer by layer.... ....Ok ill stop. Of course im fun at parties. Why do you ask?

[@Abcwhatever]

Now that it's been three years, did you get into it?

[@shubhamraj25]

@@Abcwhatever lol

[@PracticalEngineeringChannel]

Leave a dam comment and let me know what you think!

[@unvergebeneid]

You dam well, know what we think!

[@brozach1394]

Would you be able to achieve a similar effect to the "cutoff wall" by making the base of the dam longer? It obviously wouldn't be as efficient, but would it work?

[@jevaikramullah8798]

Practical Engineering hi grady great video as always ,could you make a video about ground vaccum and how it reduced water ,thanks before and sorry for my bad english

[@TheBrokenLife]

I'll be dammed if I do, sir!

[@cojawfee]

Where can I get some dam bait?

[@poster99999999]

Great video! However I felt like it was only the introduction. I was hoping you were going to spend a bit more time on the model and the various conditions or examples.

[@mspeir]

Agreed!

[@moritzkockritz5710]

poster99999999 yeah, I was a little surprised when the outro started

[@cantsolvesudokus]

me too, think he could have build a cutoff wall on the new model and have shown the difference between failure and a stable dam.

[@mrreymundo5383]

I too would have enjoyed more discussion of mitigation techniques, and some demonstrations of those techniques. Also some animations of actual dam failures and their causes would have been great.

[@TheForcedinductn]

Same.

[@miniman3112]

"Engineers generally try to avoid building civil structures out of liquids." :D

[@gennadyreshetnikov5948]

True story!

[@StratoSound]

Well, concrete, technically...

[@Zheeraffa1]

Well, they let it set and become a solid first, technically...

[@athenseed6041]

it isn't a solid when set

[@ZilogBob]

Only a real engineer would say that.

[@thefjk]

"seabitch"

[@raysilins6326]

That is exactly what I thought

[@justindie7543]

led by captain Theon Greyjoy

[@stevewalston7089]

You beat me to it ...

[@lexibigcheese]

that's me.

[@alephkasai9384]

What is he actually saying

[@TheOrangeAngle]

Dam that was a good video

[@Yonatan24]

*_Thlake you :)_*

[@colonelstriker2519]

Did you two just

[@Yonatan24]

Make horrible puns? Yes.

[@Cynyr]

I think you meant it was a great dam video :)

[@phuturephunk]

OH YOU!

[@RandallStephens397]

@3:16 "Engineers generally try to avoid building civil structures out of liquids" [citation needed]

[@zanmerd3033]

Water makes soil liquidy, so engineers try to avoid such areas.

[@wacky.racoon]

I also need a citation for this

[@exhumedlegume8870]

Concrete: Am I a joke to you?

[@theKashConnoisseur]

Practical Engineering: Where you learn more in a 5 minute video than you did in an entire semester of classes.

[@thaton3guy100]

The Kush Connoisseur you must be doing something wrong in your class then

[@theKashConnoisseur]

Yeah joe, it's definitely got nothing to do with the quality of the instructors.

[@suchaccountwow4858]

The Kush Connoisseur But dont blame it all on the instructors tho. No matter how good the instructor is if you still foolin around it will be the same.

[@thatjared4303]

I have to say that my teacher, talked about Donald Trump all semester instead of teaching the subject. The only way i do learn is by watching videos like this.

[@theKashConnoisseur]

@Such Account Wow No matter how studious the student is, they cannot learn if the teacher doesn't teach.

[@montykoolaid]

I seriously hate seepage. Ruins my underwear.

[@lescovar693]

Excuse me what the fuck

[@anitadervishi3807]

Hahaha The first time i heard him say it i thought he said "sea bitch"... 🙉

[@M4xxey]

@@anitadervishi3807 i had to come to the comments to stop hearing "sea bitch"...

[@blahblahblahblah2837]

3:56

[@Agaetis181]

@@lescovar693 hey don't be racist

[@mute8s]

Grady if you ever become a super villain you need to call yourself "The Hydraulic Gradient" get it? Because your name is Grady.... Dam it seemed more funny in my head... :) Anyhow keep up the good work.

[@TheMrblessed]

i laughed; so, it was kinda funny!

[@feynstein1004]

Take your like and get outta here

[@y0h0nk27]

@@feynstein1004 but why?

[@jeffreyquinn3820]

@@feynstein1004 Dammed if you do, dammed if you don't.

[@feynstein1004]

@Jeffrey Quinn Hah

[@Fwumiko]

What? I wanted to see more of the model in detail with technical explanations!

[@mhhuusko]

Yeah, a slowed more thorough explanation of the mechanics instead of just short jumpcuts.

[@felixbade2879]

Yeah! More demo, less talking face, please! The talking itself is great, but I can’t concentrate when the visuals are gone. I could watch those demo model clips like 20 time without getting bored.

[@AV1461]

My thoughts exactly. I was waiting for a case by case demonstration with time-lapse sequences or so.

[@TomJakobW]

Koishi Komeiji it's quite a fine "line" (well, it's actually continuous, you could always increase the depth a bit and a bit more); popular science or in-depth science. This video could be 2 hours long with formulas and simulations (I would love that, honestly), but that would change the target audience. It's basically the difficult situation for a content creator to decide, how much to "dumb down" but still keep it interesting and scientifically correct. But still I agree with you, I want more, too.

[@AV1461]

That's not quite the point. The thing is that he seems to have got a bunch of awesome footage, but none of the experiments were presented from end to end. Maybe they're on another video. I personally was waiting for the point were he would stop speaking and let the experiment run. But you're right when you say that it's tough to produce a 5min video with everything necessary.

[@CopperCreekCuts]

Dam, you must be under a lot of pressure.

[@elitegamer468]

First quick, think of somehting funny... . . . Dam failure is what my parents call me. Edit: wow internet engineering man likes me now.

[@OutOfNamesToChoose]

I still get seepage after two shakes :(

[@jogodeplanilha]

lol: internet engineering man

[@joanalbertmirallespascual3606]

"Engineers generally try to avoid building civil structures out of liquids." That's what water benders are for.

[@MaximKretsch]

No, that's what ground freezing is for. :-)

[@cryptfire3158]

I'm guessing "water bender" is from the same movie i watched last night. "The last air bender"

[@blackfox2885]

@@cryptfire3158 That movie doesn't exist. Watch the show it's much better.

[@edwardteach3000]

@@cryptfire3158 Movie? What movie? The never made an ATLA movie!

[@cryptfire3158]

@@edwardteach3000 i watched the last air bender on netflix, it's probably still there. In the movie, the kid comes out of frozen state like 500 years later, he has a bunch of powers, there are only pockets of people who can control elements.

[@wolfbd5950]

3:16 "Engineers generally try to avoid building civil structures out of liquids" is the best sentence I've heard this year.

[@stevengiallourakis5816]

Not sure where to leave this comment. I just had surgery for my 4th cancer and i found your channel while i was in the hospital. It has been the perfect thing to help get through this. I am about to graduate with my degree in Applied Mathematics and i love engineering. The demonstrations you do are great and i have really enjoyed watching them. I know its something that most patients might necessarily find entertaining while in the hospital, but i did lol. So thank you friend! Keep up the great work!

[@Mortumnus]

That's a quality video. I wish there was more channels like this on youtube.

[@WonderfulBoness]

Mortumnus does someone know anyone like him on yt

[@feynstein1004]

For physics, PBS Space Time is definitely the best. And Kurzgesagt is good for science in general. Don't know about others.

[@asdfghyter]

There are actually many channels like this on youtube. The difficult thing is to find them.

[@lontongtepungroti2777]

3blue1brown, welch lab, real engineering

[@saketshelke5912]

There's Vsauce, Physics Girl,Simone Giertz etc

[@calyodelphi124]

That outro suddenly coming up after only a couple of minutes kinda caught me off-guard. It felt like the video ended just as you were in the middle of giving the lesson about this phenomenon. D: I'd be interested to know how quicksand and liquefaction poses dangers to infrastructure and just structures in general, particularly in seismically active areas like the San Francisco and San Jose Bay Area where land has been reclaimed or even outright built using soil fill, as well as the considerations that civil engineers must make when designing for infrastructure and structures in such areas.

[@Renegade30]

liquefaction is a major concern for civil engineers. It can be helped in a number of ways, 1. Avoid saturation of the soil by providing surface drainage or dewatering pumps 2. Create what's called a floating structure that is neutrally buoyant with the soil (usually by making a large basement) 3. Allow relief of soil pore water pressure through some mechanism such as an underground drain These issues are well known and only really an issue in poorer countries where lack of maintenance, shortcuts or corruption occurs.

[@calyodelphi124]

Although these issues are well known, they can still affect more economically developed regions as well. Particularly in areas that haven't been updated with infrastructure retrofits to solve these issues. Especially if it's a region that has a tendency to either neglect or conveniently forget about (or simply can't afford) infrastructure maintenance, upkeep, and replacement, until it just decays to the point where it fails outright and absolutely must be replaced.

[@Ktulu789]

Calyo, I felt that the video was short too. I think that he took more time building the model than showing it's effects and behaviours. For one thing, the building "time lapse" seems longer than the demonstration footage xD

[@nuttynut242]

All soil liquefy if you shake hard enough. However you can do stuff to the soil to make it more resistant to liquefaction. Ground improvement like jet grouting to increase the overall shear strength of soil is one method. For land reclamation projects, the use of a correctly graded soil followed by sufficient degree of consolidation is one way of dealing with liquefaction risks during a designed seismic event.

[@nuttynut242]

@@Renegade30 Longterm mass dewatering cause other problems mate. Don't do it mate. The other 2 ways you mentioned are methods to deal with settlement and consolidation not liquefaction.

[@MordecaiSumarai]

I wish our dams here in South Africa had more water in them.

[@MarktheRude]

Well you could fill those reservois with communist; they're not human but they are still made out of around 60% of water.

[@halimceria]

but communist is red. no one want to drink red water. they all want aqua-blue capitalistic democratic water.

[@TheUserid82]

Bennie Pretorius perfect time to enlarge the reservoirs when the water is low to get normal equipment in. Even if you make them so deep you can't get flow from them they still let water seep into the ground to recharge the ground water. More capacity means when you do get rain more is captured and not lost out to sea.

[@TheIndogamer]

Deep.

[@Marmocet]

Reverse osmosis desalination plants powered by a nuclear reactor can deliver huge volumes of fresh water for hundreths of a cent per liter and they can run almost continuously for at least half a century. They're a good solution if water shortages are chronic and you live somewhere where people are capable of maintaining infrastructure.

[@ancientmonkey5327]

Did you know the Hover Dam was supposed to be twice as tall as it is now? After some re-evaluation, they thought it would be 2 dam high. I’ll see myself out...

[@AksamRafiz]

Stay out.

[@Orsan_]

This is absolutely fantastic! As a civil engineering student myself in a land full of sub-soil water, I get really excited about this kind of videos analizing soil mechanics failures general,because we don't tend to visualize the phenomena this precisely. You are an inspiration and a great source of knowledge. Keep going! Hopefully, if someday I get to be a teacher, I'll make my students understad what they're learning through this kind of amazing demonstrations. Greetings from Mexico!

[@patrickeh696]

Which is why you bring the footing down to bedrock.

[@PracticalEngineeringChannel]

Not everywhere has bedrock close to the surface.

[@patrickeh696]

Of course not. I learned that in geology class over 40 years ago. But, that just means not everywhere is suitable for a damn. ;) I left the latter unsaid as it is obvious to anyone who knows a bit of geology.

[@dicksonteoh]

And over overconsolidated soil, clayey soil's bearing capacity is dependent of cohesion too.

[@WarrenGarabrandt]

This got me thinking: does everywhere have bedrock? I mean, do we just dig down until we hit a lot of rocks and call that "bedrock", or is it a solid slab of rock that literally spans the entire tectonic plate with no gaps (except volcanos I guess) and no way around it?

[@massimookissed1023]

Warren Garabrandt , different areas have different types of bedrock and at different depths. Sometimes a decent bedrock is just too deep to be economically viable to reach. Manhattan has skyscrapers at either end because of decent hard schist bedrock; not so much in the middle though.

[@movingheadmau8128]

wow your videos are very high quality and also very informational thx for sharing! :)

[@ronniepirtlejr2606]

I fell in quicksand one time & almost died! If I would not have had my blow-up raft in my hands, it would have been curtains for me! It took me around 10 to 15 minutes of fighting, hanging on to this raft before I was able to climb out. You would think it would be easy to see right? No, there is a fine, dry dust that covers the top of it so, it appears to be just like the rest of the ground.

[@mbainrot]

I'll be Dammed if any structure I build ever stands the test of time :) #dadjokeoftheday? Thanks for the very informative videos, it's interesting to see how such inanimate stuff like dirt can reek havoc. Particularly how the piping causes a positive feedback loop

[@probablynaz1731]

"that damn seabithch"

[@ramsaimaruti4923]

Saw this channel for the first time. Great video and accurate description. To prevent piping, along with cut-off walls/ sheet piles, inverted filters are used too. Inverted filters are the ones with coarse grained on the top and fine grained on the bottom. With increase in surcharge on the d/s side, the critical condition of hydraulic gradient is hard to occur

[@Bird_Dog00]

That got me thinking. Could you mitigate the effects of piping by one of these measures? -driving piles deep into the ground below the dam -excavating deeper and filling the ground below the dam with a mix of soil, gravel and larger rocks -injecting concrete into the ground below the dam

[@ZweiSpeedruns]

I'd like to see the full time-lapse of the dam failure if possible, I'm a bit sad there were only a few scattered clips of it

[@thumbnail8087]

If this happens in real life .... You will say "DAMN"

[@PyreVulpimorph]

The quantity of puns in these comments IS TOO DAM HIGH! ;P

[@folf]

Pyre Vulpimorph DAM RIGHT!

[@derricka7751]

I sea you tried to fix that by lowering the quality of puns with your comment.

[@ibtgb2]

These videos actually really help. I'm a general contractor so it's nice having at least a basic understanding of these things when I'm working with civil and soils engineers or when we run into problems in a job.

[@privateinformation9384]

Could you build a model showing the affects of fracking? With all the dialogue going on about this subject (both for and against), it would be interesting to see an engineer put it to the test in a controlled environment.

[@ElNeroDiablo]

This video was good. It was dam good! I love how practical demonstrations such as model actually give you physical and easily seen information about the situation being modeled! :D

[@MegaJonSA]

Greetings from South Africa. I'm a recently graduated civil engineer. I remember learning about this at university and manually calculating flow rates by drawing flow nets. It's great that you're making these concepts more understandable to the general public and hopefully, in doing so, inspiring some young minds while you're at it. Great work!

[@Fede_uyz]

"engineers generally try avoid build civil structures out of liquids" i'd say thats an understatement

[@Jemboj2895]

3 Gorges Dam has been real quiet since this video.

[@smurfendrek4791]

Amazing video, your demonstrations really make this stick with you forever, instead of it just being some formulas you forget.

[@urphakeandgey6308]

3:56 That was actually a lot more dramatic than I thought it would be. I was expecting some rinky dink "disaster" since it was just a model.

[@volvok7749]

Even among YT channels dedicated to science the quality of your content stands out. Thank you very much!

[@RedWingsninetyone]

Very strange that I've been watching a lot of your videos on dams recently just prior to 2 dam failures near my brother's house.

[@YouPlague]

I'd love to see longer footage of the model, possibly the whole process.

[@prathameeshthakur]

Hoping that China has built robust cut off wall in 3 Georges dam(there will be too much seeping because of 2020 floods) otherwise............

[@tisFrancesfault]

Nobody likes seepage.. it gets ...messy.

[@TheUserid82]

Unless they are trying to get larger ground water reserves.

[@arifahmad-7261]

I am worried for may comming chemistry paper😭😭😭😭😭😭😭😭😓😓😭😭

[@Taytyaaytyat]

"Engineers generally try to avoid building civil structures out of liquids" LOL!

[@inesgurtler5749]

Could you maybe also do a video on QUICK CLAY- maybe also in relation to dams and other structures? I know its quite similar, but it would be really interesting to see more about it!

[@GuyNamedSean]

This is a great way to start my day.

[@Willycfw]

You talk about theories. Dams engineers know not to build a dam on sand (or permeable foundation) without a proper seepage cut-off.

[@werds1392]

Chi Wan isn’t that kind of the point of the video?

[@Abdega]

"Dam Failure" Hey that's my nickname! Haha…ha… *sob*

[@rp003.0]

nice one m8!

[@mpmc5563]

I had to turn subtitles on to understand that he was saying seepage and not sea bitch... I'm defiantly not well today! lol

[@PixelBytesPixelArtist]

“Oh no, we’ve fallen into nesquick sand!”

[@LOL-dq9cl]

Im i the only one who is bothered by the not straightened foam on the background? Or is it my ocd?

[@marcelowind]

Just wanted to let you know that I really enjoy your videos. This might get buried under an 'seepage' of other comments.. But just putting it out there

[@Token_Nerd]

Petition to get Grady to show the multivariable darcy's law and explain it.

[@greenmario3011]

> S E E P A G E

[@The_CIA]

*My father always called me a dam failure...* _I should've told him it was because of quicksand..._

[@samraymond4464]

Anyone else keep hearing "sea bitch"...? 😂😂😂

[@apb_134]

Me watching engineering videos at 3 in the morning: ._.

[@FecheVolta]

Hey Grady great video as always, but a little on the short side. Would've liked to see some more examples. Can't wait for the next one!

[@Lillireify]

Had my teachers shown me your videos during my studies... Nobody would fail their classes :) your videos are not only very informative, but also extremely interesting and easy to understand :) keep up your amazing work!

[@keegan707]

Your build and use of dye makes it really easy to see exactly what is happening. Thank you, your awesome.

[@CTRLyurself]

I really couldn't give a Dam about this stuff

[@Migueldeservantes]

So if all Dam always leak, do you have any idea what is the volume lost on the Huber Dam? I mean this as a question, I'm not trying to test you or challenge you.. so no insult intended.. Great work by the way! I always keep looking for your next video! wish could be a patron. may be one day!

[@imchangingaccountnoreason1103]

you must make the DAMN DAM REACH BEDROCK

[@GabrielTobing]

2:10 I love how the water just goes up, forgetting all about the 9.8m/s gravity acceleration that is supposed to make it go downwards.

[@DextorPlays]

Clearly explained seepage and the mechanics behind it. Felt like the solutions sections was short or unfinished. Not that I know what those would have been if any, just sharing the feeling I got.

[@u_wind_sprint4393]

A wall. A space time wall. Maybe we could use the galaxy. Travelling only to solar systems on the other side of the galactic plane. Because if we don't, then our local gravimetric pressure could punch a hole in space creating a semi permanent wormhole. Or really, a black hole where the pressure is more and an explosive white hole where the pressure is less. Traveling to star systems farther away than our own cosmic backyard would be best for all, ironically. Thank you for inspiring the dream!

[@Calebscott360]

“The answer to the question has been answered in a previous video, now watch my sponsor “

[@Moon_x_sun]

Every time he said seepage it sounded like seabitch

[@keiyakins]

"If you've ever built a dam ... in the gutter on the street" ... Guilty.

[@Tommygunn776]

That one acoustic tile in the bottom left corner bothers me

[@bullymaguire793]

Every Engineering college in this world should demonstrate in this particular way. In india, our college are just making us memorise things without understanding how things are actually happening. Great video.👍

[@tHaH4x0r]

I am not a civil engineer, but an electrical one, and I can see a lot of similarities between seapage and creepage in high voltage circuits. The principles why current can flow through air (breakdown) is of course different, but the system that arise do behave similar. The cut-off wall is practically the same as what is often done by increasing isolation by making for example slots in PCBs. Now a question from me, another thing that would help I can imagine, is cascading, thus reducing the pressure of each dam. Is this actually done in practice? I have never seen cascaded dams myself.

[@MateusSponch]

Man, I love your videos. I like that you put formulas and we can understand it easily this way. I just wish that video were longer. You could show, for example, dams that failed because of this effect. Thanks for sharing information!

[@Renard380]

I believe this is what happened with the Malpasset dam in France. When i read the conclusion of the survey i thought the dam had detached from the mountain on one side but when i visited what's left of the dam (left untouched in memory of the many people who died that night) i noticed a huge hole in the ground going under the dam. So i think i understood the survey report wrong and what really happened was what you describe in this video. A very interesting and also very sad place to visit. A true example of the incredible force of water. I saw concrete blocks bigger than a house strewn miles away from their original place along the river bed, i just couldn't belive my eyes.

[@AshokTudu]

very beautiful video...well made and well explained...i doubt anyone made a more better video than yours....👍👍

[@pladin517]

Grady, have you thought about getting sponsored by engineered material companies? I'd suggest reaching out to business development managers in innovative building materials. I'm probably not the only construction field engineer that likes your content, and you'll do so much better to talk about a new geogrid than a subscription service to shaving cream.

[@lorenzo42p]

I've stepped in some sort of quicksand mud once. was visiting a local river. the day was about over and we were about to leave. on my way back, thought I'd just jump off a small hill down to the river stones, no more than 2 feet down or so. one foot landed on solid stones, the other foot landed on some mud which looked solid. it ate my entire leg. if my other foot wasn't on stone to catch myself, I would have been mud from head to toe. it amazed me how it was rock hard in one place, then barely a few inches away, endless mud. interesting.

[@ddeakpeti]

Could you make that piece of acoustic black foam sticked on your wall (bottom left corner of video) to be horizontal? It's just burning my eyes. Thanks.

[@blank6521]

This video was such a dam failure

[@FurryEskimo]

Maybe I’m crazy, but would adding boulders under dams help reduce this seepage affect? Maybe it could reduce the damage caused during a catastrophic failure?

[@Migueldeservantes]

I try to like it many time but I only can like it once.. great job!! I feel really good envy of you man!! great job...

[@davidgermain]

makes you wonder about the 3 gorges dam?

[@NjK601]

What's going on with that Three Gorges Dam? One minute it seemed about to flood, and was supposedly shifting, then it just fell off from the news one day

[@MetalAgainstMetallic]

0:21 is the Teton dam. I live a few miles away from it. There are still damage scars in the area from it

[@OCMElPolo]

I'd be interested in knowing if similar principles apply to man made islands like in Dubai. Can tides create the same effect? It does in some natural areas I think

[@AndrewNowacki]

Levees usually use sheet piles or slurry walls to prevent seepage - they go all the way down below to an impermeable layer like clay, so most seepage paths are prevented to the greatest extent possible.

[@oreodog]

Wouldn't it be more effective in terms of increasing the length to make the flow wall perpendicular to the dam, kinda like flooring

[@lexprontera8325]

L I Q U I F I C A T I O N not "lique-" but "liqui-" ..... ..... not "-faction" but "-fication" ...for the same reason that "clarification" is not "clarifaction". Glad we got that CLARIFACTED, so let's move on to more productive things.

[@rotulaelectrica]

Your video reminds me of a story that the professor of hydraulic structures told us during a class, in the University. "The mayor o a small town decides he wants to have a dam on a creek. He builds it and soon after its completion and fill-up, the supervisor comes rushing to him. Mr. mayor, there is no more water in the lake. How can that be? It's impossible. No sir, there is no more water... ... Soon after, discovering that 10 km downstream a village was flooded" Btw, awesome videos you have. Thanks for sharing the good stuff, the engineering stuff.

[@fallingfloor6924]

*Long ago in a board room* Sir, we've learned from our mistakes and are calling this phenomenon "seepage". Admittedly we are baffled to a solution. Some single mom's kid in the back somewhere: "WHY DON'T YOU DIG DEEPER?!"

[@benb3316]

Cool! Hope this model is used in every engineering class... Just so any students that make it through have "I do NOT want that to happen to ANY project I have a hand in!!!" in the back of their minds. And given how much public funds are looted to give the Koch bros their latest handouts we need them (the next Engineers) scared to make things 150% better than they have to be so they can last longer...!

[@OwenKoenig]

So is the solution of a cutoff wall just to make a damn with a deeper base in the ground? Are there other practical and economical methods to prevent seepage?

[@codywhen]

"Hey look buddy, I'm an engineer. That means I solve problems, not problems like 'What is beauty?' Because that would fall within the purview of your conundrums of philosophy. I solve practical problems..."

[@BXNProduction]

Why not just make the bottom of the dam with re enforced concrete? No seepage then, someone tell my why that’s not a good idea

[@Spaceman420Spliff]

Practical Engineering, I have heard that hydroelectric dams are harmful for their rivers because they make the outflow water "too clean", i.e. the water doesn't carry enough silt, compostable debris and nutrients downstream. Are there examples of dams that have taken this problem to heart? Conversely, have there ever been dams that have failed because of a buildup of silt/debris. P.S., very cool channel! I only just found it today, but I have really enjoyed your work so far

[@zmnali78]

This video is what makes youtube important, very simply explaining very sophisticated stuffs. A quick question, in your other video which explains the "mechanically stabilized earth", I wonder why home builders don't use this MSE technics to stabilize the soil beneath the house foundation? would u please elaborate on this

[@jasonmarkson3773]

Why not "Cure" the bottom of the dams fill side with powdered clay which would (under pressure) "fill in" and compact the soil on the UP side of the dam? Much cheaper option and once the clay has compacted into the "sand", then you would have a constant barrier. Since the flow OFF the dam is from the top, then you would not be wasting much clay. The clay should be added at the end of the dam construction so that there is a more even distribution and less erosion. Clay powder can also be "fed" into the base of the up-side via pipes going down through the water. Just a thought.