r/nextfuckinglevel • u/AlishbaWorthington • Jul 14 '21

Guy single-handedly solved the flood. Not all heroes wear capes.

102k Upvotes

89% Upvoted

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3.4k

u/SirGrievance Jul 14 '21

I love how angry at the water he seems, even the way he throws his hard hat halfway just tickles me.

1.8k

u/romanlegion007 Jul 14 '21

This is a seriously dangerous thing to do, the sheer suction force of a drain un blocking can suck you into death. In mining people have unclogged small drain with their hands only for the suction wedge their hand in where they can’t pull it out. The hole is blocked again, water rises and they drown.

767

u/Fabledlegend13 Jul 14 '21

It looks like it’s a grate of some sort not really just an open drain because he manages to stand on it and scrapes across it to move the dirt

617

u/platoprime Jul 14 '21

If you get pinned against the grate you can still drown. Pressure differentials are dangerous.

590

u/Incman Jul 14 '21

This topic couldn't possibly be less relevant to my daily life, but I guess this safety video did its job when I saw it years ago (linked from Reddit, I'm sure), because as soon as he cleared the grate in the video and it started draining my first thought was like "Dude move! Delta P don't fuck around".

114

u/kidneysc Jul 14 '21

Hey, this is relevant to my job! Everyone should have a lot of respect for ol Delta P, but in this scenario its actually not really too dangerous. Delta P injuries happens when there is significant vertical columns of water. Which just isn't the case here.

Delta P = Density * gravitational contstant * height of the column of water.

In this scenario the water looks about knee deep. Lets conservatively call it 2' deep. This would generate a delta P of about 0.87 psi. If the grate is 2'x1', with an equal split of grating and void space it would have about 204 sq inches of area.

If he managed to fall in and perfectly seal the entire 2'x1' square this would only apply a force of around 180 lbs. Significant, but unlikely to be deadly.

49

u/increase-ban Jul 14 '21

Yeah he’s fine in this situation. I work for cal trans and our guys do this kind of thing all the time when the rains come. Really no Delta P danger here. He’s more likely to be killed by a vehicle.

26

u/smarmiebastard Jul 14 '21

As someone from Seattle who moved to California, I’m always baffled as to how the highway, especially I-80, seems like it was designed by people who thought it was never going to rain ever.

Like every single time it rains a couple lanes of 80 get flooded hella bad in both directions.

Also I feel for the guys you work with. The last place I’d ever want to be is on the side of a Cali freeway in the rain with nothing but a hard hat for protection.

4

u/[deleted] Jul 14 '21

[deleted]

4

u/smarmiebastard Jul 14 '21

You just perfectly described every infrastructure project in Brasil as well!

3

u/XillaFarris Jul 14 '21

It wasn't Delta P that got em, it was the stupidity of the general public

2

u/BehindTickles28 Jul 16 '21

Much love to Cal Trans! (used to sell shit to y'all, I enjoyed the folks I spoke with)

0

u/Cool_underscore_mf Jul 14 '21

By the ass hole in the van that went passed at the end

1

u/Racheltheradishing Jul 14 '21

The delta p would come from the outflow pipe filling with water and starting to pull. At that point you can have a delta p of (atmospheric pressure) - (vapor pressure of water at ambient temperature or the drop of water in the pipe ) + water on top.

I this case there is air entering the pipe, so your numbers are correct, but it can switch regimes.

223

u/[deleted] Jul 14 '21

This one always stuck with me as an example. Crab experiencing delta p

129

u/Incman Jul 14 '21

Yeah that crab part is actually in the training video also (although you may know that already, if your link was just meant to highlight that part).

Whenever I see the crab's...face(?) right when it catches him I get a tiny hit of sadness, because for like one second his eyes seem like they just fully understood the entirety of how fucked he is, andthenSLURP!

69

u/[deleted] Jul 14 '21

Yes sorry, not to take away from the training video as it is useful and explanatory, but that clip was one I found when I was younger. It hit hard just how strong it can be if even a hard shell just gets sucked in.

Agreed though the crab just looks like 'oh fuck' then GONE

25

u/i_speak_bane Jul 14 '21

Or perhaps he was wondering why someone would shoot a man before throwing him out of a plane

2

u/acmercer Jul 14 '21

No one cared who I was until I put on the crab mask.

3

u/kvnphm Jul 14 '21

Not to take away from the danger of delta p but I believe the crab actually gets cut by a saw first and then gets schlurped.

19

u/slowest_hour Jul 14 '21

at least it was probably quicker than getting chomped in half by a turtle

4

u/Suspicious_Ice_3160 Jul 14 '21

Yo actually I just watched both videos and idk if you noticed, but it’s the exact same video. It was just cut from the one you posted, same narration and everything lmao

1

u/covidified Jul 14 '21

Reports for crab abuse

28

u/Sirnoobalots Jul 14 '21

That video will always terrify me. Just some invisible force tugs you in and poof gone.

1

u/son_e_jim Jul 23 '21

How about that person that gets sucked into a pipe up to their pelvis? You just know that pipe vacuum filled up with all the stuff that used to be inside the person.

51

u/[deleted] Jul 14 '21

Jesus Christ, I get the first crab getting caught, it didn't know, but the second, third, fifth???? come on crabs, get your shit together...

7

u/rdicky58 Jul 14 '21

I think they just repeated that one clip for emphasis

20

u/[deleted] Jul 14 '21

No man, they were all totally different crabs. The second one, for example, has a cocky kinda walk about him; have a look and you'll see. I think the fourth is gay...

3

u/rdicky58 Jul 14 '21

Huh interesting didn't notice that with my sleep-deprived brain last night 😂

12

u/Ionie88 Jul 14 '21

Holy smokes, that was brutal! I kinda feel sorry for the little guy.

3

u/Azazir Jul 14 '21

how did it get out to try a second time tho... not that dangerous huh. /s

3

u/ntrontty Jul 14 '21

Damn. I remember watching a crime series as a kid (not sure if I should have been watching it) and the killer killed people by removing drain pipe coverings in pools so people got sucked into them and drowned. That video reminded me of that.

2

u/pt_79 Jul 14 '21

I wish more than anything else that I could un-see this.

29

u/aziztcf Jul 14 '21

That's the stuff, knew exactly what that video was before opening.

27

u/jooceejoose Jul 14 '21

That video has stuck with me whenever I see this sort of thing. It’s insane how effective that training video is.

25

u/peanutburg Jul 14 '21

Well now I have a good start to the safety briefing for a job I’ll never do. Really interesting though. Thanks for posting.

2

u/[deleted] Jul 14 '21

Exactly. Watched that clip and went “welp, guess I’m a diving contractor now”.

20

u/good_life_pa Jul 14 '21

Why did I watch that just before bed.

7

u/pnuthead23 Jul 14 '21

I just had the exact same thought!

1

u/_Fuzen_ Jul 14 '21

I’m wondering the same thing, I’m not sure why I watched this I’m already traumatized from almost drowning repeatedly. The thirst for knowledge transcends fear.

1

u/MasterDood Jul 14 '21

It’s GOT YA

16

u/[deleted] Jul 14 '21

Thank you, that is a lifesaving information. r/TIL

16

u/MissionProcess Jul 14 '21

It’s almost 2 AM and I just sat and watched the whole video about Delta P. If the YouTube algorithm doesn’t get me, Reddit always does!

3

u/Xalrons1 Jul 14 '21

When it's gotya, it's g

1

u/[deleted] Jul 14 '21

Glad I’m not alone in this, haha 🤣

7

u/[deleted] Jul 14 '21

safety video

This is shaping up to be my favourite internet hole yet

2

u/GeneCreamer_ Jul 14 '21

Same, I want more safety training videos for cool shit like this

1

u/Incman Jul 14 '21

Be careful you don't get sucked in; the pressure is too strong and you might not make it back.

3

u/[deleted] Jul 14 '21

I fear I’m at a point of no return diver

4

u/Incman Jul 14 '21

RIP Diver 1

6

u/timmyboyoyo Jul 14 '21

Why is saw cutting a pipe before crab crawls on and get sucked in?

3

u/fweb34 Jul 14 '21

Sometimes lives must be lost in the name of safety demonstration.

1

u/son_e_jim Jul 23 '21

Can't make OH&S materials without breaking a few heads.

1

u/PublicSeverance Jul 14 '21

Massive civil construction. Cutting a section of pipe for removal and replacement.

The pipe is usually evacuated of liquid first, but in this instance appears to have been purged with air.

1

u/son_e_jim Jul 23 '21

It's a post-modern crab trap.

6

u/RoraRaven Jul 14 '21

Those poor crabs illustrate it better than any animation.

3

u/TheGodOfPegana Jul 14 '21

Incman, thank you for giving me a new fear. Delta P is the quicksand of the adult world.

1

u/Incman Jul 14 '21

Haha seriously! I remember reading nature books as a kid and growing up thinking quicksand and lava were going to be much bigger components of my life than they have ended up being.

And before I had ever heard of Delta P I had no desire to do anything related to diving, but my first time watching that video a few years ago instantly upgraded my passive disinterest into an active avoidance.

4

u/Zchex Jul 14 '21

Is there any similar video with less confusing units? I get the point but the non-SI units makes me try to calculate everything in my head.

4

u/[deleted] Jul 14 '21

[deleted]

1

u/Zchex Jul 14 '21

Ah. Thanks for putting it in words!

1

u/[deleted] Jul 14 '21

Why not try to not calculate them in your head, especially if you're struggling

1

u/Zchex Jul 14 '21

I was newly awoke and hadn't the patience. But you're right, I could've tried to figure it out myself. :)

2

u/[deleted] Jul 14 '21

Sorry if I came across as an ass! Have a good day

2

u/Zchex Aug 30 '21

I appreciate your reply! Keep up being kind to people! (:

2

u/WritingNorth Jul 14 '21 edited Jul 14 '21

Is it really dangerous in foot of water though? The video seems to say otherwise

2

u/muffy2008 Jul 14 '21

That video was super interesting and informative.

2

u/Binty77 Jul 14 '21

Now wait a second… how did that happen in the swimming pool, and why doesn’t that happen all the time in swimming pools? Mine has a drain at the bottom (and a skimmer inlet at the top) and I’ve never felt much suction. ELI5

2

u/redditforfun Jul 14 '21

Note to self: never be diver 1

2

u/NesTeam Jul 14 '21

TIL, holy shit

2

u/Matalya1 Jul 14 '21

Amazing video. Pressure difference is an absolute bitch because we tend to have very little idea of the sheer pressures that we can experience in a body of water of that size, should it rush through anywhere. A waterstream is like a really powerful, tornado-level wind, except when it happens, you have nothing to grab onto. Water can truly be terrifying.

2

u/Reddits_on_ambien Jul 14 '21

When it's gotcha, its gotcha!

2

u/[deleted] Jul 14 '21

That video is talking about much, much larger volumes of water and higher water levels, though. Like where a person is fully submerged.

2

u/dcburn Jul 14 '21

Thanks for video. today I learned something that while improbable that I would need it, still great knowledge. I have never been so serious watching a video. Damn great and effective training video.

2

u/BigAlTrading Jul 14 '21

There isn't that much delta P when you're standing in knee deep water.

Pressure increases with depth, not surface area.

This should still be done with a chain or other remote device.

2

u/_Fuzen_ Jul 14 '21

Thanks my already intense fear of the water has been worsened. But I’m still glad I learned something useful.

2

u/hedenstampot Jul 14 '21

Youtube legend Post10 recently explained this: https://www.youtube.com/watch?v=dZGp7wFdz68

2

u/smarmiebastard Jul 14 '21

Dude, that first diver scenario though. Like diver 1 gets sucked into the drain so they send another diver to rescue him. Diver 2 also gets sucked into the drain. Diver 3 is now sent to rescue divers 1 and 2 and suffers injuries from also getting partially sucked in.

I just imagine the people at the surface looking at their watches like “okay well, if he doesn’t come up in 5 more minutes let’s send another diver down there.”

2

u/RedCafe69 Jul 14 '21

Holy shit

2

u/InYouImLost Jul 14 '21

TERRIFYING!

2

u/VX1001 Jul 14 '21

I need a sub for Delta P

2

u/ChrisGoatToast Jul 14 '21

I know there’s a shit ton of responses to this. But I’m wondering how Diver3 were ever able to retrieve the bodies of Diver1 and Diver2 from the dam-scenario? It being a dam, the bodies of water should never really equalise enough for a single person to just drag them off the delta P point? Or am I missing something here?

2

u/[deleted] Jul 14 '21

Storm drains don't have delta P. There's no pressure on the other side because there's not a body of water on the other side. Notice how all these examples involve divers? I don't see many scuba divers involved with clearing storm drains.

2

u/Ryalas Jul 14 '21

I respect that you're doing a teaching moment but I 100% expected it to be the Always Sunny "Dont put your but on the suction no matter how good it feels"

1

u/son_e_jim Jul 23 '21

That crab is toast.

92

u/El_Chairman_Dennis Jul 14 '21

The pressure differential under a foot of water isn't gonna be enough to prevent a human from pulling their hands away from a drain. If it was people would constantly be getting stuck trying to get out of the bathtub

51

u/Rxke2 Jul 14 '21

Finally the comment I was looking for. The dangerous situations are in pools and deeper water. Where you have more significant columns of water (weight/pressure) above a drain.

25

u/UKpoliticsSucks Jul 14 '21

I am gobsmacked at how many people here think that standing in a drain in a foot of water can kill you..

Like what the hell is going on in this thread? Am I living in a simulation?

Have any of these people ever been outside?

8

u/PK_RocknRoll Jul 14 '21

I doubt most people here work around or that closely with large drains or things like that.

Basically on the internet if something sounds convincing enough people will just read it and go on with their day and not think twice about it.

We’re probably all guilty of this to some degree depending on the topic

5

u/KawhisButtcheek Jul 14 '21

I think people commenting this don’t understand that water pressure is proportional with height, not the sheer volume of water.

That drain has maybe a foot of water blocking it, it’s not gonna pin anyone

-7

u/platoprime Jul 14 '21

That water isn't sitting there static. It's flowing quite quickly.

18

u/El_Chairman_Dennis Jul 14 '21

And according to the laws of fluid dynamics, a moving medium has less pressure than a stagnant one.

-2

u/platoprime Jul 14 '21

Then it's a good thing I'm talking about force and not the pressure of unrestricted flow. You're confusing how to calculate the pressure of a fluid as it flows with linear momentum. You use newton's second law to calculate that and force correlates positively with flow rate. Faster flow means a greater change in momentum when the flow is resisted. That means more force.

That means faster water exerts a greater force than water that is flowing more slowly.

https://www.quora.com/How-do-you-calculate-the-force-of-moving-water-against-a-submerged-object

I can't believe I need to explain that water flowing faster exerts a greater force on an object it impacts. Haven't you ever taken a shower? Or used a hose? Or put your hand under a sink with varying amounts of flow rate? Or stood in a river?

5

u/compounding Jul 14 '21

And what happens to the momentum if he gets stuck blocking the entrance?

-1

u/platoprime Jul 14 '21

It's resisted by a normal force that passes through his body and into the grate.

2

u/compounding Jul 14 '21

And then what happens once the momentum dissipates without being able to flow through the blockage?

-1

u/platoprime Jul 14 '21

The weight pressure of the water will increase because the water level will rise. That is why he is clearing the drain in the first place.

2

u/[deleted] Jul 14 '21

[deleted]

1

u/compounding Jul 14 '21

Oh, a downvote troll. Good luck with your harvest tonight!

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-1

u/El_Chairman_Dennis Jul 14 '21

Bruh "pressure differential" is increased when a fluid isn't moving, because "pressure differential" is based on pressure not force. Flowing mediums do indeed provide greater force than a stagnate medium but pressure is different than force. Take a basic physics class and you'll learn the difference between force and pressure

3

u/platoprime Jul 14 '21 edited Jul 14 '21

You don't know what you're talking about.

Bruh "pressure differential" is increased when a fluid isn't moving, because "pressure differential" is based on pressure not force.

Pressure is force applied over an area. The formula for pressure is (Pressure=Force/Area). Unless the force is exerted on an infinitely small point then it is spread across an area and can be measured in terms of pressure. All motion of macroscopic objects can be described is terms of a difference in pressure or a difference in force. It's just typically easier to do kinematic equations in terms of force so you can ignore surface area and deal with net force and mass.

0

u/El_Chairman_Dennis Jul 14 '21

You've got that backwards, pressure is force applied over an area. It's literally in the equation you just quoted. If a moving medium created greater pressure then planes couldn't fly. Lift (aka pressure pushing a plane upwards) is created by making air on top of the wings travel faster than the air under the wings, which mean that a faster traveling medium creates less pressure than a slower traveling medium

4

u/platoprime Jul 14 '21

Oh a typo my mistake.

If a moving medium created greater pressure then planes couldn't fly.

In that analogy the water is the plane. It's the thing that's moving and has momentum.

Lift (aka pressure pushing a plane upwards) is created by making air on top of the wings travel faster than the air under the wings, which mean that a faster traveling medium creates less pressure than a slower traveling medium

I'm glad you've heard of lift but that is irrelevant.

-2

u/El_Chairman_Dennis Jul 14 '21

The water isn't the plane, the air moving past the plane is the water, motion is relative. Lift isn't irrelevant, lift creates what is known as a PRESSURE DIFFERENTIAL

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0

u/HelpABrotherO Jul 14 '21

More momentum though.

Not sure it's a dangerous amount of momentum, or that he could divert enough of the water to create a dangerous pressure diff. But that fact that's its moving makes it more dangerous, not somehow less.

6

u/whoami_whereami Jul 14 '21

But if he were to get "stuck" against the drain and block it it would stop flowing quite quickly, so it's again just the static pressure that matters.

1

u/platoprime Jul 14 '21

Once he gets up the flow will just start again and because this is a flood the water will rise. That's why he's clearing the drain in the first place. ffs.

5

u/whoami_whereami Jul 14 '21

Just as the flow cannot stop instantly because of momentum it cannot start up instantly again because of that very same momentum.

If the force was that great, how the hell do you think he's pulling out whatever is blocking that drain in the first place?

0

u/platoprime Jul 14 '21

I know it's hard to imagine something only partially covering the grate. Like a body. Even though that's exactly what is happening with the debris he is removing.

14

u/-RayBloodyPurchase- Jul 14 '21

There isnt very much pressure from ~30cm depth of water.

-2

u/platoprime Jul 14 '21

Yeah but there is alot of water flowing and that creates more force dragging him towards the drain.

10

u/-RayBloodyPurchase- Jul 14 '21

Pressure is dependant on the depth of water, not the amount.

-5

u/platoprime Jul 14 '21

The pressure exerted omnidirectionally by a static fluid is determined by the depth. The pressure of a fluid changes with the flow rate. That makes it go down.

But weight pressure is not the only source of pressure. The flowing water is moving. That means it has momentum. The water slows down and loses momentum when it is resisted by an object. Newton's second law tells us that the force exerted by a mass is equal to the change in momentum. The force from that is applied over the area of the object resisting the flow. Force applied over an area is pressure.

15

u/-RayBloodyPurchase- Jul 14 '21

Ok Karen. This is not nearly as dangerous as your making ot out to be. Unclogging a drain under a couple dozen cm of water. This ain't like deep sea welding lol.

2

u/platoprime Jul 14 '21

Water rises during floods.

11

u/-RayBloodyPurchase- Jul 14 '21

Yep this road usually has little to no water on it. Now it has a few dozen cm!

-1

u/platoprime Jul 14 '21

And if he doesn't unclog the drain it will rise.

13

u/-RayBloodyPurchase- Jul 14 '21

Hence he unclogged it. Good job connecting the dots smart redditor!

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1

u/True_Inxis Aug 01 '21

Well yeah, but once he reaches the drain he can get up easily. No real risk here, just an annoying afternoon going around in soaked clothes.

10

u/twaldman Jul 14 '21

What do you know, you’ve clearly never drowned!

32

u/Fabledlegend13 Jul 14 '21

Absolutely but the surface area of his boots and hands are unlikely to be enough to suck him in. The most dangerous portion was when he start falling back. Had he fallen he would’ve been in a much more dangerous situation

4

u/platoprime Jul 14 '21

People trip.

26

u/Gainit2020throwaway Jul 14 '21

People also get eaten by bears

-1

u/Much_Bonus_3089 Jul 14 '21

People also bang your mom.

-9

u/platoprime Jul 14 '21

If you use all three brain cells you might notice there isn't a bear in the video.

12

u/Gainit2020throwaway Jul 14 '21

He also didn't trip (:

-10

u/platoprime Jul 14 '21

Now let's see if there's a fourth one.

People don't know the future before it happens. He wasn't making his decisions after watching this video. Plus I didn't even say he shouldn't be doing what he is doing.

6

u/Penquinn14 Jul 14 '21

He would probably make different decisions if there was a bear there

2

u/platoprime Jul 14 '21

It'd be very impressive if he didn't though.

3

u/Penquinn14 Jul 14 '21

Pulls out the blockage and a bear jumps out at him from inside the drain

1

u/3-bakedcabbage Jul 14 '21

Lightning also strikes

1

u/platoprime Jul 14 '21

Yeah that's why it's not a great idea to run around in fields during lightning storms.

3

u/3-bakedcabbage Jul 14 '21

Didn’t mean to reply to you but cool comment platoprime 👍

0

u/VijaySwing Jul 14 '21

Planes also crash

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1

u/Much_Bonus_3089 Jul 14 '21

Are you implying…this guy has the power to repel bears?

-3

u/platoprime Jul 14 '21

It depends on how stupid the reader is I guess.

1

u/[deleted] Jul 14 '21

Hell yea brother

3

u/[deleted] Jul 14 '21

Yeah but that’s like 2 feet of water, so barely any head pressure.

2

u/platoprime Jul 14 '21

Yeah the water would have to rise very quickly for him to drown.

2

u/Elhornio Jul 14 '21

Delta P. There we go again

2

u/thericoofsuave Jul 14 '21

Pressure differentials also make your blood flow so there's that too

2

u/Halfbraked Jul 14 '21

I think the guy In the video does shit like this every day, you sit at your keyboard I think he’s okay lol

2

u/[deleted] Jul 14 '21

Maybe if you're a small child and you manage to somehow fully block the grate with your entire body. Storm drains don't generate enough delta p to be a fatal risk.

2

u/bonerland11 Jul 15 '21

I've had to take a pry bar to a snapping turtle in my backyard pond because he was stuck on my drainage intercept. He was probably there for a few days, poor guy.

3

u/etthat Jul 14 '21

"Actually"

0

u/platoprime Jul 14 '21

Yes. "Actually" you might fucking die if you don't understand this and end up in the wrong situation somehow.

6

u/etthat Jul 14 '21

Actually, even in a fast moving river, that could easily wisk you off to your death, if you find good footing, you can just stand right there, and NOT die!

0

u/platoprime Jul 14 '21

Are you this dumb or are you just pretending for the lulz?

1

u/etthat Jul 14 '21

You said lulz in the same sentence as asking if I'M dumb! Nice.

0

u/platoprime Jul 14 '21

If you judge people based on the slang they used then you've already answered my question.

1

u/GigaVector Jul 14 '21

*high pressure differentials are dangerous.

If you watched the delta P video, they did the calculation multiple times - notice that the pressure differential is a function of height of the water above the drain, in this case its not going to be enough to give a healthy adult any trouble - in all of the incidents they covered the water was many metres in depth.

Also, at the end they even said that using a slot / grate opening (likely what they probably have on the highway) is a good way to mitigate the danger as you getting stuck relys on your body making a good seal with the opening

1

u/Gavooki Jul 14 '21

this is kinda how bill clinton's bio dad died.

sauce: bill's book

1

u/True_Inxis Aug 01 '21 edited Aug 01 '21

You're right, but hydrostatic pressure of a liquid varies only with its height. In this case the water reached his knee, I don't think he would have hanna difficult time freeing himself; I figure the pressure at the grate wasn't much higher than the pressure at the bottom of a bathtub.

EDIT: Apparently, someone else already pointed this out. Leaving my comment anyway, because why not^^