How Do Flood Control Structures Work?

[@PracticalEngineeringChannel]

👷Interested in videos on flooding? Subscribe to follow along! practical.engineering/email-list ▶️ Get CuriosityStream AND Nebula for 26% off! curiositystream.com/PracticalEngineering ▶️

[@MattsAwesomeStuff]

Actually... clicking the link, it's 41% off, not 26% anymore. From a dozen creators, I've been ignoring the Nebula ads all year long and finally just realized you said "per year". Rather than sounding like an ad-read about why it's nice... you should emphasize, it's currently *$11.79 PER YEAR* . Per year! For all of these educational channels. And, since most people won't be into it for themselves, you should really stress memberships as gifts. $11.79 PER YEAR for all this educational and entertainment content. I'll probably actually sign up now. I was figuring it was going to be like, $50-100/year and my eyes just glaze over and my brain turns off.

[@Dan_Fahl]

Climate change is a hoax

[@ValDominator]

i love floods

[@CS-Student]

@@Dan_Fahl If you believe that climate change is a hoax, you're gone already, lmao.

[@NappyWayz]

Speaking of water could you do a video on lawn bubbles? I find them interesting and wonder if you have any insight.

[@Yora21]

On the North Sea, we also often get floods that are not caused by too much water coming down, but by the water not being able to flow into the sea. Especially in winter we often get extremely strong winds from the West. Just the wind pressing only on the water surface in the river slows the water flow enough to make all the water coming behind pile up. And being one of the flattest large open areas in the world, it doesn't take much to flood really big areas.

[@johnsmith1474]

The largest flattest open area on Earth is likely in Siberia, then perhaps the Great Plains of the USA, I cannot think of any place with Western exposure to the North Sea that is even 1/100th as large. And what you referring to is tidal surge not the slowing of river flow by wind. But I am interested to know where you are located ....

[@sudazima]

@@johnsmith1474 the netherlands..

[@Yora21]

@@johnsmith1474 European plain goes from Spain to the Urals.

[@ncot_tech]

Spring tides where the moon pulls more strongly on the incoming tide does this too.

[@stabileseitenlage]

@@johnsmith1474 To be fair, I think living at the sea he would know what the tide is and how it effects the sea and rivers. I never heard about wind hindering the flow of rivers, but I can imagine it to a certain extend.

[@KavehMagaura]

The simulation of the hydraulics would be a great DLC for Cities: Skylines

[@stevecarter8810]

God yes, whenever I put a dam in in CS IT breaks my brain.

[@greenconscious210]

@@stevecarter8810 I've spent so much time and (game) money trying to optimize hydro-poo dams for good electrical generation

[@IstasPumaNevada]

I'd very much like that. Unfortunately, simulating water flow realistically is computationally expensive, and often requires compromise (hence the wonky water flow in C:S).

[@fireofdestruction7753]

@@IstasPumaNevada its been 5 years since release I'm sure theres something now they could do to improve the water physics

[@applemachome]

I enjoy having ships go over dry land with a weird configuration of dams.

[@CS-Student]

Love this channel, despite having no connection with engineering. Knowledge always benefits everyone. Thank you for making these informative videos, Grady! :)

[@Cythil]

We all have a connection to engineering since we lived in an engineered environment. So it is good to have at least a basic understanding of how these things work. I bet a more than a few of use live near a waterway for example. And now we might have a greater understanding why we can and can not do certain stuff around that waterway. Or why some argue so much about how to manage it. ;)

[@kevincangjaya661]

indeed, such as his saying "instead of reducing flood, we try to reduce the flood consequences" in which I think is a good thinking pattern not only for engineering

[@squidwardo7074]

I'm a programmer, despite knowing fuckall about engineering I still love this channel

[@TheSuperhoden]

@@Cythil meh, knowing it doesn't add value as humans specialised. So hes right and hes not involved. Hes a passive bystander

[@wompastompa3692]

Levees are pretty neat. Drove my Chevy to one, but the river was dry.

[@frankpinmtl]

Were some good old boys there? Maybe drinking some alcoholic beverages, like whiskey and rye?

[@fourtwelve412]

Perhaps they were vocalizing their eminent deaths? Could have occurred that very day, you never know.

[@christaylor8337]

@@frankpinmtl Sadly, I do believe that they all died that day. At least they got some booze and pie in them, so it wasn't a complete loss.

[@the.starman]

Probably sang "This will be the day that I die"

[@h.p.734]

@@christaylor8337 lmaooo nice

[@MagusSartori]

I would love to see you talk about beaver in the context of rivers, water, and flood control. Beaver ponds and dams have been shown to reduce flooding by increasing the carrying capacity of the water system, allowing the whole system to absorb more water before it flows downstream. Also, considering that beaver were ubiquitous in the continental united states prior to western colonization, the flooding of rivers which we consider normal might well be abnormal and caused by beaver's local extinction

[@myrojyn]

I also want to learn more about dam beavers. I think it'd be great to learn about dam behavior overall

[@mikekahl5609]

I've never seen a beaver lower the water level in his damn to reduce flooding. What ever water flows into his pond has to come out the other side. Unless the water level is lowered, damns can not control floods.

[@iwanabana]

exactamente!

[@MagusSartori]

@@mikekahl5609 Not quite. Remember that beaver dams act like a large number of partially filled ponds dotted along waterways. So when heavy rains fall the dam-pond has unused capacity to retain that water that would normally rush down stream immediately. As for release, after the storm the water will evaporate or seep away into groundwater over time rather than needing to be release. An individual pond will likely only have a fraction of the water capacity of a man made dam, but with many beaver damns over an entire river system it's capturing a huge amount of water that would normally need to immediately go down stream and possibly cause flooding. Then releasing that water slowly to the ground across a huge geographic area

[@JordanHowellMusic]

That’s crazy and crazy awesome! I never really thought about that…would like to see some scientific studies or other research into this, if you have any sources or links! Either way, it’s a cool thought, and even though may be more of an …ecologist/zoologist or something, expertise, im sure Grady would have some insight on it! Heh!

[@MajoraZ]

Flood management and historical hydraulic engineering often gets talked about with Romans and western societies, but there's actually quite a of them for Mesoamerican civilizations like the Aztec and Maya. The Maya city of TIkal for example had huge public rainwater collection reservoirs (as well as individual ones for specific households) with canal systems and levees between them for drainage if one reservoir overflowed and the streets, buildings, etc had channels and drains built into them to redirect the rainwater into them. There were also grids of channels to move water in agricultural areas and from more frequently flooded areas to less flooded ones, and aqueducts with multiple paths and switching stations to change which way they delivered water. There were also smaller reservoirs and canal systems strategically placed out for hundreds of square kilometres in a sprawl of landscaped suburbs around the city center. Meanwhile, The Maya city of Palenque, in contrast to TIkal, had problems where rather then not having much access to freshwater and needing complex systems to collect it, Palenque had dozens of springs and many rivers inside the city itself, so it''s massive interconnected systems of aqueducts, underground pipes running underneath plazas buildings, and streets, canals, pooling basins, etc were designed to move water out. At least one of these underground aqueducts was pressurized to make a large fountain, and the city had some toilets. Another example located in the temperate to arid hills of Central Mexico rather then the tropical lowlands during the same period is Teotihuacan. It also used agricultural canals and rainwater collection reservoirs, and it also re-directed rivers that cut through the city and were turned into geometric canals that went along with the city's grid layout, aligned with specific landmarks in the city, such as having it run alongside the Temple of the Feathered Serpent, which had water associations. The plaza in front of the temple could also be flooded for religious ceremonies. Some of the city's residential complexes (which, were almost all lavish, multi-room palaces, even for commoners), also had plumbing systems, and had running water from rainwater reservoirs, to use for drinking and cooking. The city also had toilets, though how they connected to other water systems is unclear. Fast forward another 1000 years, the core of the Aztec empire was dozens of cities and hundreds of towns all built around and on the islands in a lake basin. Many cities, Especially for the capital of Tenochtitlan, used grids of artificial islands to expand the usable land with Venice like canals between them. Tenochtitlan also had a complex series of aqueducts (including a dual piped one equipped with a switching mechanism), causeways, and levees to manage water flow and link it to other cities in nearby. Probably most impressive is the water system for the personal gardens of the rulers of Texcoco, the second most important Aztec city, which was designed by one of it's Kings, Nezahualcoyotl , a renowned poet and who designed a few other aqueduct and levees. This system fed water from the Mexican Sierra Nevada mountain range 5 miles away (at some points the aqueduct rising 150 feet above ground level) onto a hill nearby the gardens, had a system of pools and channels to control the rate of water flow. The water then crossed over a huge stone channel between the gorge of that hill's peak and the peak of the hill (Texcotzingo) the baths were on, at which point the channel formed a circuit around the top of the second hill, filled the baths and a series of shrines and aesthetic displays (complete with statues, painted fresco, carved reliefs, etc), and dropped water off via artificial waterfalls around key points of the gardens below. It's all really cool stuff and it's a shame Mesoamerican history isn't taught more.

[@pennyforyourthots]

Is Tenochtitlan the city where they built it over top of a swamp by putting logs into the ground and letting them petrify into rock-like structures to build on top of? I vaguely remember there being a city like that somewhere in mesoamerica, but I don't remember which one it was specifically.

[@MajoraZ]

@@pennyforyourthots You're mixing some information up, but I think you're thinking of Chinampas, which is indeed the artificial island technique I describe that composed most of Tenochtitlan's area, where a section of the lakebed was staked out with logs then filled with soil, and that soil anchored to the lakebed via planting a tree on it, with the land used as either hydroponic farms with canals between the plots acting as irrigation, or as additional land for constructing more buildings.

[@cageybee7221]

there was also the amazing water management system in the kingdom of angkor, in modern day vietnam and cambodia. that area has a dry season/wet season system from monsoons so the kingdom organized massive canal and resevoir systems to control the summer floods and provide during the winter droughts. infact the reservoirs were actually a requirement to stabilize the foundations of many building in angkor-wat, the capitol. unfortunetly one really bad several year drought defeated this system and half the capitol fell into a sand pit. but for a couple hundred years it worked great.

[@blazertundra]

Also the Hohokam of what is today the southwestern USA. Their irrigation canals are what made the harsh desert habitable for human communities. Even after they disappeared, the more recent Native tribes refurbished them for their own use. I've heard some of the canals that cut across Phoenix suburbs today happen to be the same canals dug over a thousand years ago.

[@fourtwelve412]

This is awesome info from you all. There's always details I hadn't learned before. And I also agree, wish I'd been taught more Central and South American history in school

[@cranemon]

The Red River Floodway is a neat example of a flood diversion channel. At the time of its construction, it was the second largest excavation project in the world behind the Panama Canal. It protects the city of Winnipeg annually from spring flooding and is estimated to have saved the province billions of dollars in flood damage. The sheer volume of water that you can see passing through it at peak flood is mind-boggling.

[@nicholaspatton1742]

You are a great teacher. You have the ability to explain diverse concepts, breaking them down into simple understandable blocks that you then rejoin as easily. As a renovation carpenter(retired) and life gave me a common sense understanding of engineering, but I often lacked the precise terms and such. Well done Grady!

[@markmackela1246]

in Ann Arbor, MI, there are two parks on the north and south sides of the city which surround ponds which were built/expanded to divert/slow down vernal streams which might otherwise flood the town and nearby farmland. It’s a real neat idea, I think, and makes for some beautiful wetland park areas

[@hirshkabaria8329]

Which parks are these? is one the arb?

[@mitchellfolbe8729]

Go Blue!

[@tomb7088]

@@craigjensen6853 Hines Park was built in the 40's to do just that. Years later they built a road and made it a park.

[@impmeister1]

After many years I finally know the word, americans use for dijk Levees! Greeting from the levees capital of the world (the netherlands)

[@PracticalEngineeringChannel]

Some do call them "dikes" after the Dutch word

[@utuberme1]

kzbin.info/www/bejne/fHeniqiFaph1i80

[@MlTGLIED]

Yeah, greetings from Ostfriesland

[@Leon_Schuit]

@@PracticalEngineeringChannel I would love it if you made a video about how the Dutch manage waterways and the tide. I think a lot of our infrastructure is cutting edge, and that our engineers are among the best in the world when it comes to water management. Even our king is internationally involved as an advisor on water management.

[@timusmaximus6794]

The sea can not beat us!

[@oetgaol]

In the Netherlands we started to reconstruct the natural path of rivers and creeks to slow down the river and increase the water capacity a river van hold. Also we are in the process of giving rivers more space. We saw the fruits of that effort Just this month where a montage sim of rain was dumped in a couple of hours but flooding was somewhat limited especially compared to 93 & 95 when a similar amount of water flowed down the river.

[@brokentombot]

I feel like I knew this stuff by intuition. Then I watch Practical Engineering and realize there is a lot more going on. I love how he adds so many interesting details and bonus facts.

[@jonathanbaker1961]

For those of you wondering, at 5:16 that diversion channel is in Worcester, Massachusetts

[@lazkatarn]

Thanks a lot!

[@jackgriffiths4199]

I love this channel. I may be biased as a Civil Engineer, but this may be the best channel on KZbin. Thanks for all the hard work and high quality content!

[@fireaza]

*"OH MY GOD! WHAT'S THAT BEHIND YOU?!"* -Diversion Canal

[@Lyudovik1917]

I live in a relatively upstream area of a river, and the town is built on the confluence of two rivers. while im not in danger from the flooding, i do visit the rivers often and calm streams become violent, tearing, ripping monstrous forces. It just goes to show how powerful these things are. An intresting thing is the smaller river is more at risk to flooding because it takes less to overtop the banks, but when it does it fills entire areas, whereas the other one can take more water without flooding. Either way walking and hiking along flooded rivers is fun (if your careful) as its interesting to see the difference between a flooded and non-flooded river.

[@DanHiteshew-oneandonly]

The new approach of increasing absorption rather than allowing run off is a promising one. Love all your vids. Keep them coming!

[@sikachu]

This video reminds me of how Tokyo is dealing with flood by building an underground storage tank, which is really such an amazing engineering invention. Basically, it's similar to the diversion at 5:36 but instead of going into another river right away they go down to underground storage tank first, then those water got pumped out after storm is over. Actually, we were living next to one of the river which is used for flood control during the typhoon last year. It was very surreal watching the live camera feed seeing the water level went up to 80% height line, then it started decreasing because they open the diversion gate down to the storage. In the end, our area didn't get flooded, and I'm so thankful for this piece of infrastructure.

[@tonysuda9066]

It's very impressive

[@mattthe2nd865]

I wish I had you as a teacher in school.

[@Milk-ew4pf]

We all do

[@angelaburton7741]

Got a flood protection ad before the video about how flood control structures work.

[@serial507023]

How old dams are replaced? Isn't it is really difficult to say "Replace Hoover Dam"? Not now but some time in future

[@aadityarajbhattarai46]

After the time comes river is diverted, dam is destroyed and realigned. It easily and quickly becomes a sustainable thriving ecosystem after that.

[@typrus6377]

It depends. Dams that impound rivers, streams, etc will require emptying the reservoir then diverting flow to allow for repair, replacement, or outright removal. For storage reservoir dams where the water is pumped or diverted in, they shut off flow in and empty the reservoir.

[@SuperAWaC]

@@typrus6377 another option is building a temporary (or permanent) dam in front of or behind the existing dam

[@thesneakinspider3193]

There are plenty of dam removal videos here on youtube, they can give you a sense of how the smaller ones are taken care of and it seems some commenters already got to the larger ones.

[@nicolasbousquet7463]

it's not that simple, beside the simple economics "dams are damn expensive, and whern there is no damn there is no income from power generation" there is also water supply problem. hovver dam keep las vegas and a lot of other place afloat. if you empty the hoover dam tto make a new one, there will be a shortage of water for decades also, the colorado river is running out of water, hoover dam get less water every year and so is lake powell behind glen canyon dam, so having a new lake to refill in those condition is absurd (just to state how much water you need to fill a lake: lake powell filling took 20 years and got full to the top only once in 1982

[@arthurcarlson2855]

Amarillo TX something I have found is that the more parking lots that are close together cause major flash flooding. Personally I would suggest that any new development or rebuilding of these lots should require either a holding pond or tanks under pr around the lot that connects to public storm drains and that the release of these storage systems are in part or fully managed by the drainage department. We have 2 creeks that feed the Canadian river, and one called timber creek south of town used by the city of canyon that is probably to far to use reasonably. We already use Amarillo and cherry creek's for the largest part of north Amarillo and large pits for the rest of which some get pumped to the creek but most don't.

[@arthurcarlson2855]

Edit or

[@jamesbizs]

Something about a fire hydrant being underwater, I find funny lol

[@MegaBCAD]

The most dangerous fires are on a boat that’s surrounded by water

[@crazyeyez1502]

@@MegaBCAD or a submarine

[@kenbrown2808]

there is a photo of a fire response to a house fire in a flood, where they are simply pumping up floodwater to fight the fire.

[@gravelydon7072]

If the hydrant in front of our home in Ohio was underwater, it wouldn't be funny. It would mean that the Ohio River was about to flood everywhere South to the Gulf of Mexico. We are above the flood plain of it by about 100 feet.

[@alohathaxted]

Sort of like drowning fish.

[@blueyesfaerie]

Got to witness this in action a few weeks ago! We have a number of flood management/risk management dams close to me, most of which I've visited under average circumstances. Over Christmas we had a rainstorm come through that dropped a few inches of rain and melted the remainder of the snow pile from a previous storm. One of the dams that usually has no reservoir behind it had 20 feet afterwards! It was remarkable to see and really illustrated the importance of those structures in that area.

[@DerykRobosson]

When flood control was mentioned, what immediately came to mind was, "Nature, to be commanded, must be obeyed."

[@EggBastion]

That's a good quote! Google says Francis Bacon like I believe it anymore

[@WanderTheNomad]

@@johnsmith1474 real boomer moment

[@nicotti]

One of the most interesting flood mitigation strategies I've seen a dam do: One particular super rainy season the reservoir had filled almost to the tops of the spillway gates. So they opened all the gates to raise the flood pool for the whole lake an extra 4'. The lake is several 100 acres, so that's a lot of extra flood water storage.

[@iamdave84]

We had a super rainy season in Dec 2010 - Jan 2011 and the dam operators left it too long before releasing any water. The end result was a much worse flood downstream than should have been. So much so that the flood victims won a class action against the dam operators for negligence. amp.abc.net.au/article/11745632

[@FuncleChuck]

I feel smarter already.

[@ieuanhunt552]

@@truneighborhoodwatchtnw2127 you beat me to it

[@jameslaw165]

Uu

[@goodtoshi]

Imagine what will happen if you subscribe for Nebula

[@volvo09]

What the heck, i feel stupider

[@getchasome6230]

Issa flood of information 🤔🤣

[@MisterNohbdy]

The teleporting water at 4:15 is strangely hypnotic.

[@DFSqu]

I appreciate your interest, passion, and presentation of topics like this (and all your videos really). I like learning about things like flood control, but I've never gone out of my way to learn more about them. Thanks for what you do.

[@DamnJuhl]

There's a subtle change about this video that I appreciate. In a past video you mention property before lives and in this video you mention the importance of lives before the importance of property and I know it's small but I appreciate this framing better.

[@alihassan389]

It's great to see that linking between this video and my hydrology course 😅 Thank you 💝

[@TenzaBurabura]

That is the best definition of a water shed I have ever heard, thank you!

[@csours]

I've visited the Onion Creek neighborhood here in Austin, and it's kind of freaky to see the aftermath of a flood buyout program.

[@TheAndyLittle]

I made a wrong turn and ended up driving through there. Surreal.

[@dennis2376]

I watch a KZbin were a whole town moved to higher ground, federal and state instance no doubt, to stop the town from being damaged each time it flood. Wild. Now buy outs are common. In Alberta, Canada after a flood homes were not allowed to be fixed and go bought out.

I confess that most days when I open KZbin I just wish that Grady has made a new video. This channel is the best!

[@lunchboxproductions1183]

For some odd unknown reason I've been obsessed with hydrology since I was a little kid so all of these dihydrogen monoxide infrastructure videos lately are really tickling my fancy!!! Much appreciated

[@the0neskater]

I have never clicked on ads on anything, especially on KZbin but today I have broken that. Firstly to support your channel but also because the deal looks very good and the content looks excellent, exactly what I enjoy and want to watch. Thank you and great video / content!

[@mango9087]

I really like the idea of "resiliency". Me any my hippy friends talk about "living with the land", but resiliency sounds like a practical, empirical measurement of how much an area is "living with the land". Im starting to think I need to go to school for engineering...

[@mango9087]

@Mr Brightside Well you misunderstand the term, from what I gathered from the video.

[@Turtle1631991]

Isn't that very close to "redundancy" - the idea that you overdesign for extreme events and unlikely failures in proportion to criticality of the system? Those concepts can be applied anywhere. We can see it right now that businesses without liquid reserves for rainy day are failing due to lockdowns...

[@richarddrum9970]

Structural flood reduction measures can be effective if based upon accurate, historic hydrology and sound engineering and are especially good for protecting densely populated urban areas. Where development is less dense such as rural areas bordering waterways, non-structural measures (flood proofing and relocation) are much more effective and cost effective. Structural measures also require substantial, annual operation and maintenance costs to the local community whereas O&M costs for non-structural measures normally rests with the individual property owner. Great video.

[@engineermerasmus2810]

Me who lives on top a of a hill: Pathetic

[@lamcho00]

Wait until the landslide episode.

[@rain_xix]

that one tectonic plate: "Im about to bring down this man's whole career."

[@johanlugthart7782]

Me living a few meters below sealevel...

[@nicolasbousquet7463]

me who live near a gigantic natural lake with a dam regulated level: hold my beer (haha , flood?)

[@Ostsol]

Our river lies in a valley up to a hundred-fifty feet deep. There are low-lying regions of the city, but the bulk of it is on high ground. The only flooding we get is due to drainage issues, mostly in underpasses.

[@RealHypeFox]

The tone and cadence always puts me at ease. Continue making great things! Sending love from north of the Red. 🌪

[@spicybaguette7706]

Floods are also increasing because of the destruction of vegetation, which normally absorbs the water and releases it later on

[@richarddrum9970]

True, loss of vegetative cover results in increased runoff since trees and other vegetation absorb and transpire tons of water in forests. The other problem is the increased installation of pavements (roadways and parking lots) in urban areas that do not absorb much rainfall leading to more water in the stream or river that exceeds carrying capacity.

[@amoth7757]

Locally, giant housing plans have been deforesting swaths of land, but they also build on the adjacent flood plain, putting more and more strain on the watershed. Got rid of the forest, got rid of the wetlands, and put giant slabs of concrete down to funnel it away. Much of this has some sort of regulation that’s supposed to stop this but they unfortunately let people get away with empty promises, bribes, or the bare minimum (not future proof). Real sad shit to be seeing this destruction in real time :(

[@CharliMorganMusic]

Can you make a video about why Texas couldn't handle a blizzard? Like, I want to know everything it couldn't handle about it. It'd be like an Earthquake in the Midwest, I imagine.

[@timsmig8809]

You always improve my knowledge. Thank you 🙏🏻 😊

[@honeyboiii]

Honestly one of the best channels I have subscribed

[@pawesedrowski6743]

Great video, however I believe you missed the most efective flood control structures - so called small retention. A lot of small hand made wooden structures located upstream or on drainage ditches can stop and slow down the water and prevent overfilling of the rivers downstream. Beavers are also good at that. Natural grasslands and forest keep a lot of water too - if we destroy them the water rushes to the rivers and then overfills them. Maybe you could make a video about that? It would be really interesting to see your point on that. :-)

[@banksarenotyourfriends]

Right! I was waiting for the part where he explained that planting trees upstream can protect cities downstream by increasing the infiltration of water into the land and slowing flow, instead of trying to get it off the land as quickly as possible. I guess it doesn't count as engineering...!

[@pawesedrowski6743]

@@banksarenotyourfriends Well, let's be honest a forest or some tree trunks across a stream or a ditch don't look as spectacular as an enormous dam. Most people have a tendency find those as unnecessary or even harmful. Even a lot of hydro engineers would like to plan rivers flow with a ruller and cement the riverbeds to make the water flow faster and they are not able to predict that it will cause problems downstream. I was really hoping that Grady (@Practical Engineering) would at least mention that as he has a really big audience and he could make more people aware.

[@LucarioBoricua]

There's also detention ponds, which use a concept similar to the flood control dam, but at a much smaller scale and intended to mitigate the impact of really intense rainstorms in small basins/watersheds, such as those formed in urban areas (neighborhoods, parking lots, shopping malls, factory/warehouse buildings...)

[@PracticalEngineeringChannel]

I did a video on urban stormwater management that talks about some of these smaller solutions. This video was really meant to talk about the three main types of large-scale flood control structures.

[@elementalsigil]

Another great video. I'm sure in practice the stuff contained in this video is beyond boring to any but the most driven floodiphiles. Thanks for making it so we can all enjoy it.

[@StrokeMahEgo]

When you see a cool-looking concrete flood control structure: *DAM!*

[@nov4rus579]

Over the years now I've realized why my local parks have big open fields that are sunken into the ground, other than a big open area to play and have soccer on, it's more like an ingenious idea. Open land for recreational use, but when it does rain, and its not often, those fields flood and connect to underground waterways. I never actually thought what would happen if those parks were never there until this video gave me more insight on the variety of flood control structures. Without those seemingly inconvenient fields to get in and out of my town would flood heavily each time it rained.

[@arpitamondal7539]

Hi Grady, I have personally benefitted a lot from your videos, and have been using some of your videos in my undergrad hydraulic engineering class in IIT Bombay, India. This is a request from me - can you make a video on decommissioning of dams? We teach a lot to our students on how to build dams but nothing at all about how old and dysfunctional dams may be decommissioned. As a matter of fact, there are hardly any dams decommissioned in India so far. It would be nice if you could share. Thanks a lot, and keep great content coming. Best wishes, Arpita

[@Peregrineeagle]

Love the discussion of Resilience, it's such an important development in planning. I'm currently working on my master's Architecture thesis on how historic structures can fit into resilient systems in coastal areas at risk from sea level rise, so it's great to see such a succinct and clear explanation of why resilience is important!

[@DAUKGinjaNinja]

This video wasn’t available on Nebula yet so had to watch it here. Would prefer to watch on Nebula. Great vid anyways. Thank you.

[@PracticalEngineeringChannel]

Sorry about the mixup! I usually have my videos on Nebula the day before they are released on KZbin, but there was an error with the upload that had to be fixed. It's up now!

[@CordCrenshaw]

I just want to know how you get the lighting so good in your studio. I can’t even see the lights reflected in your glasses. That’s some engineering magic! 🪄

[@crazyeyez1502]

Had this old Chevy. Drove down to the river for a picnic. surprisingly, the levy was dry. 🤷🏻‍♂️😏

[@jaysmith1408]

When you got there, did you by chance notice what the good old boys were doing?

[@iamdave84]

They were drinking whisky and rye

[@crazyeyez1502]

It was a long long time ago , but they were singing hard.

[@TheOtherBill]

Meanwhile, on the other bank, the banjos are syncopating.

[@joshuapatrick682]

I woke up to 3-4 ft of water in my neighborhood one day. The night before it rained harder than I thought was possible dropping feet of rain in a matter of hours and while there was definitely pooling, the water channeled in from the surrounding area over the next few hours after the rain stopped, was awful, had to get rescued by a boat.

[@mistrants2745]

8:07 this is a rather American view. In the USA they seem to be rather focussed on fixing things back up after floods while kinda accepting they will always happen. This does not have to be the truth though. The Netherlands being a prime example of flood control done right.

[@TedSchoenling]

Spoken like somebody who has never seen the vast area of the US and doesn't realize that many of our states are larger than the Netherlands and have different non-coastal flooding requirements.

[@nemodl]

@@TedSchoenling Fair point with regards to the size difference! Though Netherlands is also doing a lot of river management, seeing how it is located in the Rhine-Meuse-Scheldt delta...

[@vsmoraes0]

Netherlands' land reclamation projects are extremmely environmental damaging. If such projects started with the knowledge we have today, they'd not even be accepted.

[@tubester4567]

@@TedSchoenling I agree, the cost involved in the US compared to the Netherlands is huge. The US is like 5000 Netherlands in size.

[@mistrants2745]

@@TedSchoenling the netherlands is one giant floodplane. The ocean isnt the only concern.

[@Turtle1631991]

This makes me think back to horrible floods we had in Czech Republic in 2002. In southern part of the country there is ingenious system of ponds and fisheries from 16th and 17th century built on what was originally marches. During those floods this system was able to withhold many dozens of millions of cubic meters of water without significant failure in 400 year old engineering while at the same time some much more modern damn experienced such failures. Always makes me appreciate just how important this work is and proud history of it. Not to mention Holland where they have to constantly pump water out since they are quite a bit under sea level. It is quite freaky when you walk up that damn and then from the top you can see that sea actually is higher then where you climbed from...

[@PfunkNH]

"don't feel like it cant happen to you." I live on top of a mountain I think I'm alright lmao

[@gus473]

¯\_(ツ)_/¯ Landslide, down to flood level, seems possible!

[@PfunkNH]

@@gus473 all granite

[@ProfessorPesca]

Even mountains can suffer from surface water flooding.

[@PeterM_K]

I'm Dutch...

[@gus473]

@@PfunkNH Didn't NH's famous "Old Man of the Mountain" just break off and crash to the ground a few years back....? 🤔 Just sayin'....! ✌🏼

[@tiffanysandmeier4753]

Rapid Creek that flows through Rapid City, SD. A devastating flash flood killed several people in 1974 (I think). After the flood, most of the land that flooded by the creek was purchased by the city and turned into parks and other green space. Some commercial businesses were allowed to stay, but have issues getting permits to alter them.

[@LordWiggle]

You should check out the Dutch Delta works. You'll going to love it.

[@willhikearizona]

I was in Houston during hurricane Harvey and the flooding started a couple days after the rains had stopped and the reason I was told was because they had to release water from the levees upstream to prevent them overtopping. Would be an interesting video to discuss this event specifically.

[@Noah_AWICB]

These videos are always interesting, thank you

[@laernulienlaernulienlaernu8953]

On a site a long time ago, a guy who was tanking out a basement said to me - you can't stop water, you can only try and control where it goes. Very true.

[@opensourceguy730]

I remember the late Arthur C. Clarke saying that we shouldn’t call our planet Planet Earth, but Planet Water since most of it is covered with H2O. 🌏

[@peglor]

If you want to really be accurate, the Earth is covered with a mix of mostly nitrogen and oxygen. By mass, there's an awful lot more rock/earth than there is water though (Even if you only count the rock in solid form).

[@youammay3118]

What about the other layers that are inside the planet?

[@opensourceguy730]

Ok, so I should have been more precise in what I wrote and said the surface area of the planet is mostly covered with water. :)

[@peglor]

@@youammay3118 The other internal layers aren't covering the planet though... :-D

[@youammay3118]

@@peglor Well noticed ! Thanks dude :D

[@daniels4742]

I love these videos you make about water and the incredible work needed to control it. I learn alot!

[@shaka626]

I just graduated as a Civil Engineer from University of KZbin. 😂. Thanks for the video P.E

[@jxmai7687]

don't forget put that into your resume.

[@VijayabalajiB]

Thanks for high quality, informative videos like these. I always look forward to your uploads :)

[@BlackDragonWitheHawk]

In Switzerland, at the lake of Thun in Thun they built a tunnel to help flood control, but it doesn't realy solve the problem, it just shifts it down river... to solve the problem humans would need to give the river space again to meander and or flood fields in it's original valley... Soo... no more floods in the lake of Thun, but now they have a higher chance of flooding in the lake of Biel or the city of Bern

[@EnbyFranziskaNagel]

Bern: thanks. 🙄

[@jaysmith1408]

The most fascinating dams I’ve seen are in the Miami Conservancy District. Dams between fairly small and surprisingly gigantic (it doesn’t hit you how big the actual dam is, until you realize how big the reservoir actually is) are fairly simple, just big mounds of dirt with a culvert through it. The culvert is properly sized to flow the channel, but any overflow backs up into, jinkies, a reservoir.

[@danielmatias3929]

5:11 Porto, Portugal!!!!

[@NenucooPT]

PORTUGAL CARALHOoo! Orgulho Portuense !

[@admiralcapn]

Still waiting for the Practical Engineering breakdown of the Oroville Dam disaster. This video was a great lead-in!

[@peterfireflylund]

No, a watershed is the *border between* drainage basins.

[@9HighFlyer9]

Nope, it's the area not the border. The border doesn't shed water the land does. Thus, it's the watershed.

[@peterfireflylund]

@@9HighFlyer9 You must be American. Anyway, your folk etymology is wrong, both for the noun “watershed” and for the verb “to shed”. You can see the real etymologies on wiktionary. (Hint: there is a reason the German word is Wasserscheide.)

[@9HighFlyer9]

@@peterfireflylund You must be German. My etymology was kind of tongue in cheek, sorry. You may be correct as to the origin and historical usage of the word. However in American English "watershed" refers to the land area that drains into a stream or river. "Divide" is the word I'm familiar with for the boundary of a watershed.

[@mccutcheogeoff]

A great example of flood control infrastructure from my home town is Red River Floodway. the 2nd largest earth moving project in the world when it was built. it is a massive ditch that diverts flood water from the red river around the city of winnipeg.

[@typrus6377]

For the reservoir example, look into the Estes Park Dam and the 2 major Big Thompson floods.

[@ethanwild3301]

*Me who lives in Houston: you guys don't flood out all the time?*

[@PeterLawton]

Ha, ha! I will never forget when I saw the replay of Hurricane Irma: it went over Houston (bad), slowly (worse), then stopped and backed up over Houston (much worse), slowly (OMG Bad!), then stopped again and went forward over Houston a third time (WTF!), slowly. I thought, "NO WONDER it flooded!".

[@Jake9066]

I used to live in Houston... watched a car be carried down Kirby by floodwater back in 2013 (I think) back when they were ironically increasing the capacity of the storm drains

[@ethanwild3301]

@@Jake9066 That must've been crazy to watch. Yeah every time it rain for a while I always see all the drains get instantly clogged

[@mafarnz]

Galisteo Dam in New Mexico is a great example of a dam built solely for flood control. It’s normally dry but has a storage capacity of 152,600 acre-feet. It’s an impressively huge structure too!

[@The_Hairy_Farmer]

As farmers we've gone from Tick Eradication to Tick Control.......to Tick Management....

[@iamdave84]

What next?

[@jankubat2694]

I'd almost say, that's Orlík Dam in the Czech rep at 7:15 I have seen it "in action" managing the flood (1000 year water) in 2002. Even opening the floodgates wasn't enough and the water overflowed the crown of the dam, it was terrifying.

[@jankubat2694]

Watching some other aerials, it most certainly is Orlík.

[@mrxmry3264]

the problem with levees is that all they do is shift the problem downstream.

[@Gruncival]

That can be okay if downstream is a natural habitat that can absorb and return from the overbanking water. But yes, it's been a big issue when there's a community every 10 miles along the same river as is common in human history.

[@rabornevines7399]

Grady, you're a gem. Thanks.

[@Itsthefry69]

Science.

[@Sir.Craze-]

Some people watch horror movies. Others ride roller coasters. I, like to watch large scale hydrodynamic engineering videos for that kind of mix of fear and thrill! And I'm only joking a bit xD 🎩👌

[@GuyNamedSean]

Me, who lives in Houston: Snow pack? What's a snow pack?

[@owensilberg2966]

Was 2017 the last year it actually snowed here?

[@cjhification]

For about the last 5 to 10 years the policy in England has been to make space for water, and slow the flow by returning meanders and renaturalisation river channels, planting trees to both shade the river to adapt to climate change but importantly to stabilise the channels. We have also had a flood and coastal erosion risk management department within the Environment Agency, who manage flood risk in England for at least 10 years, if not 15. It changed from flood defence department nomenclature.

[@acwright]

There is a serious problem with this video that you need to address. It ends too soon.

[@caringancoystopitum4224]

There hasn't been a single flood in the entire 1300 years old history of my town. Then again, all the rivers around us are up to 100 feet below the lowest point of the city and we are located about 2000 feet above sea level so there is a pretty slim chance of a flood here ;)

[@gabrielgomescunha]

Not building in flood areas would solve the problem

[@lordkapuze9496]

I think you will find that it's almost impossible to build in a non-flood area. or at least these areas ithink are hard to find.

[@Stormcrow_1]

Depending on the size of the country you might well find it's a case of too many people, and not enough places that don't flood.

[@tymoteuszkazubski2755]

Where I live people settled in flooding areas for a long time, they built their houses on mounds and put U-shaped levies around their fields to protect them from flooding damage. It allowed sediment to settle and fertilize their fields.

[@gabrielgomescunha]

@@lordkapuze9496 try Switzerland, or where I'm from originally, North of Portugal or look for any populated mountainous regions. It's not difficult just not convenient. We humans are lazy. We could also build houses on pillars of the ground or on stilts or floating homes it's all better than having all your live washed away every time the river farts

[@gabrielgomescunha]

@@Stormcrow_1 you would be surprised on how wrong you arr

[@pufthemajicdragon]

I think this connects well with your last video, but maybe you could make one more in the series that connect the dots? One of the ways that a lot of municipalities are using to manage flood risk is to require homeowners to manage rainfall on their property. The aggregate impact of this can be huge without the massive infrastructure required for the major projects in this video. I've seen this in a few This Old House videos where they're required to install an underground holding tank to store water shed from the roof and driveway of a home so that that water doesn't run immediately into and overwhelm the city's drainage infrastructure.

[@user-mt3en9ly5d]

"If you haven't, be careful in thinking it can't happen to you" *laughs from the top of a hill*

[@electronx5594]

You just need to wait, For the water level to reach you

[@user-mt3en9ly5d]

@@electronx5594 dude I live ~160m above sea level up the side of a gorge that funnels directly into the sea. If the water reaches me, then shit's gotten real dire.

[@seattlegrrlie]

The Seattle area realized that wetlands and swampy ponds gave flood water a place to go. I've watched them build seasonal ponds as well as fancy holes in the ground to act as emergency reservoirs. It's made a huge difference in my local community every year.

[@andyc9902]

Those ponds can work as fresh water holders too

[@oogrooq]

If it keeps on rainin', levee's goin' to break When the levee breaks, I'll have no place to stay.

[@danbert8]

A great example are the Miami Valley flood control dams and associated metroparks around Dayton, Ohio. These dams have no lakes and no active control. The are essentially giant detention ponds. The area behind the dams is reserved for park land that won't be as devastating during a flood. I think more metro areas should have these kinds of protection in place.

[@padraicfanning7055]

When the Miami Conservancy District was established in the years following the Great Dayton Flood, the village of Osborn, Ohio was slated to be in the middle of the Huffman flood plain (just north of what is now Area A of Wright-Patterson Air Force Base). In addition to its residents, Osborn also had the main lines of three railroads running through it. The rail lines were re-routed to go through a nearby town (back then) called Fairfield (the very same town that initially refused to let the rail lines run through there). The very interesting thing was that the residents of Osborn decided to *relocate* (rather than abandon) some four hundred homes to new foundations along Hebble Creek nearby, some of which are still standing today. A few decades later, Osborn and Fairfield decided to merge, creating what we now know as Fairborn, Ohio.

[@Niendorf_an_der_Stecknitz]

"Nearly every major city us susceptible to floods" People living in mountainous areas : You dare underestimate me mortal? Landslides : Yes.

[@ryanf4497]

In May 2019, Tulsa received record rainfall. The Arkansas River flooded parts of the city after the Army Corps of Engineers opened the dam upstream at Keystone Lake even though the levees were outdated. I had never heard flood sirens until then and those are eerie sounding.

[@tristanc6967]

"Flood Control Structures" is a verbose way of referring to Halo rings. Anyway, their purpose is to remove the galaxy of all sentient life.

[@mfaizsyahmi]

I would argue that the ability to control flooding is a hallmark of human civilization. Ancient Egypt and ancient China, among many other riverine settlements, got a big boost when they started building levees and irrigation channels, which reduce flooding and increase agriculture yield. One downside of levees is that siltation will eventually make the river bed actually higher than the surrounding floodplain, making flooding of the latter even more severe as there is no easy drainage against gravity. You should see a cross section of the Yellow River in the alluvial pan area. The difference between river bed and plains level is astonishing.

[@Lunavii_Cellest]

What the netherlands is doing with levees is destroy them and rebuild them a lot of meters away from the river so if there is a lot of water i can flood the parts with nothing on it and it leaves the important parts dry

[@jaydee2100]

If only the German government was subsribed to your channel...

[@G1NZOU]

I've lived next to one of my city's balancing lakes for years, when flood conditions happen on the river a gate can divert water into the two linked lakes which has high banks, if the flood is so severe it threatens to overtop the lake there's a weir to let that floodwater back into the river system. They also kept the various river valleys as parkland so there's very little building, it's just used as recreation or occasional grazing land. I get to visit Norfolk quite often as well, they have Dutch style water pumping so previously wetland areas can be drained for farming, while the Broads get interconnected with the tidal rivers. In high flood conditions the Broads Authority have an agreement with certain farmers to allow their fields to be flooded to divert floodwaters from more vulnerable areas.

[@merelyChirs]

But why does the intro sound like a sales pitch?

[@sagealyxander]

thank you so much for captioning these videos!!