What Happens When a Reservoir Goes Dry?

Reservoirs are a solution to the tremendous variability in natural water supply, but what happens when they stop filling up?
People use water at more or less a constant rate and yet, mother nature supplies it in unpredictable sloshes of rain or snow that can change with the seasons and often have considerable dry periods between them. If the sloshes get too far apart, we call it a drought. And at least one study has estimated that the past two decades have been the driest period in more than a thousand years for the southwestern United States, leading to a so-called “mega-drought.” (Source: www.npr.org/2022/02/14/108030...)
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[@awnage]

A severe drought seems like a good time to do extensive maintenance on exposed sections of the dam.

[@cmwh1te]

Maybe, if you expect the water to come back someday...

[@iamjustkiwi]

Maintenance on American infrastructure? Sorry, we don't do that here. We prefer to spend way more reacting to disasters AFTER the lack of maintenance leads to them tyvm! I wish that was actually sarcastic but it certainly seems to be our approach.

[@marcogenovesi8570]

@@iamjustkiwi Everything is fine until something breaks

[@OlYables]

Silver lining practical action!

[@vgamesx1]

@@iamjustkiwi That may be confirmation bias since we don't tend to hear much about "this infrastructure was patched up to prevent a disaster" but yeah I still agree, we don't like spending money doing preventive maintenance around here which leads to a good few stories of things breaking or worse. I mean, as some other comments pointed out as a reminder, we still have lead pipes because nobody wants to replace them...

[@bill_and_amanda]

one point i think maybe this video could have hit a little harder was that reservoirs are sized based on the demand predicted by planners when the reservoir was built. However, the meteoric growth of a lot of areas of the southwest in the last 40-50 years was, to an extent, unforeseen. So not only do you have less water coming in than normal, you have more water going out than expected, exacerbating the problem.

[@mechanick184]

Great point

[@ScruffyCityFishing]

Or farming crops that were not in practice at the time. Almonds for example in California.

[@ErnstKotze]

The same problem in Cape Town, South Africa.

[@deanlawson6880]

Yeah that's a really good point Bill!

[@mytech6779]

@@ScruffyCityFishing An acre of almonds doesn't use any more water than an acre of peaches plums or apricots. The literally use the same roots in many cases.(Via grafting.)

[@braticuss]

Back in the day, plenty of people predicted this would eventually happen. It wasn't rocket science... moving millions to the desert was bound to be a disaster.

[@brokendownoldman9547]

This is Great!

[@umberto488]

That....and record temperatures every year.

[@frictionhitch]

Actually it has very little to do with the people who live in the desert. Look no further than the almonds, strawberries, and beef in your local grocery store. That's where the bulk of the water is going.

[@bl8388]

We have known for decades. But living in dessert states isn't a disaster. They will have to conserve the water better, and the last few years of droughts has forced the issue. Even then most people in desert states use low water dish and clothes washers, and other conservation ideas, already. They might need to add some water lines from other parts of nearby sates, and drill more wells.

[@BijanIzadi]

@@bl8388 how would drilling wells affect the water table though

[@jimsnow8004]

I did a motorcycle trip through the S/W in June '22. I saw reservoirs 40% down immediately after the spring melt. Farmers were irrigating during the heat of the day, because that is when they were scheduled to draw, using high volume, high position sprinklers that have much more evaporation rate than the more expensive low volume, low elevation sprinklers. Grass lawns were irrigated everywhere in a climate that is naturally semi-arid scrub land. There was new house construction near dry-as-a-bone Sacramento when the water supply is obviously failing. Much could be done in a very short time.

[@oldrrocr]

OK, I do understand. In the north, we conserve water so that southern california can squander it, building thousands of houses per year which make money. Money used to bribe politicians to take even MORE water from the Delta - to make even more houses.... But can't you even JUST TRY to use the water more efficiently? If you ever go to SoCal you see just how wasteful they are with this water. Watering their lawns (or even sand dunes that will become lawns), and NO EFFORT to conserve or even use it wisely. Maybe we should charge MUCH more for it.

[@bl8388]

Yes, anytime I see irrigation during the heat of the day I cringe. So much better to irrigate as much as possible in early morning, after midnight.

[@glenmchargue5461]

@@oldrrocr I'm with you. Can we just try? I stayed with my brother in a recent trip to the Menifee area, and their entire housing area is just a large oasis in the middle of the desert. There is flowing water in the gutters. Hundreds of houses with lawns. No creative xeriscaping like I've seen in the Tucson area. It isn't about survival, or what is needed. It is purely a visual use, they want it to be pretty, all green, no brown. And I passed more and more new construction.

[@FowlerAskew]

It sounds pretty analogous to energy scarcity and grid capacity. It seems like people are very resistant to small efforts to schedule energy consumption, resulting in huge demand surges during peak hours

[@shitbird9429]

Landscaping makes up for 1% of water usage, lawns don't really matter. Also, sacramento has tons of water above and below ground, we just don't get rain for much of the year

[@derekmorgan6344]

A couple of years ago Cape Town faced “Day Zero” when all the water supplying dams would run dry. It was a close run thing where emergency measures were enacted to allow citizens to fetch water from designated municipal/government sites. An extended period of water saving measures avoided having our taps run dry. It’s easier to survive without electricity (also a problem in SA) than without water! Fortunately rains since then have been good (enough).

[@Chernobog958]

But but, what happened to their lawns?!

[@MinedMaker]

I remember hearing about this in the news, even though I live on the other side of the Earth. Glad things worked out.

[@MichaelGooden]

This is happening right now in Port Elizabeth, South Africa. One dam is empty (too low to extract, even with barge). Communal standpipes have been built. Many suburbs have intermittent water as reservoirs can't refill enough at night to fill downstream reservoirs. Our country also faces loadshedding of our electricity supply for up to 6 hours a day.

[@ChomoBidensMules]

even black people miss apartheid

[@fredtaylor9792]

Just the idea of the taps being dry would send people into a panic if they actually saw them dry.

[@blazertundra]

This is why the massive exodus to the deserts of the Southwest can't continue indefinitely. The Sinagua and Hohokam people abandoned many settlements throughout the Southwest long before Europans arrived, and I think unsustainable droughts were a major factor in what happened. They left a lot of canals that we still use today, so it's clear they were dealing with a water scarcity of their own. It seems we're still making the same mistakes today.

[@ZeoCyberG]

Yes, in some cases worse. Like the first 50% of California’s water flows out to the Pacific Ocean for fish and environmental purposes. Water in California is shared across three main sectors. Statewide, average water use is roughly 50% environmental, 40% agricultural, and 10% urban... and they basically tell just the urban users to conserve... Among many other bad decisions in that state.

[@neurofiedyamato8763]

@@ZeoCyberG you also have to consider what areas can be cut back on. Environmental use is very vague... But for agriculture, we can be more efficient but the crops need a fixed amount of water. Unless you want food scarcity on top of it. Reason why urban water use gets cut is there are a lot of wasteful uses that can be cut compared to other sectors.

[@paulelderson934]

What's the mistake? People are living there now and they're fine. If water scarcity would become a daily issue for people, they would move.

[@christophkogler6220]

@@ZeoCyberG saying '50% of California's water flows out to the ocean' is disingenuous because it makes it sound like 50% of the water people have captured or could use is being wasted. It's not. The truth is that nobody is going to pipe an isolated stream from northern Calfornia 200 miles south to the cities that could use its water. "Half of California’s environmental water use occurs in rivers along the state’s north coast. These waters are largely isolated from major agricultural and urban areas, and their wild and scenic status protects them from significant future development." It's not even primarily a state legislature problem, its a population density and usable water problem, being exacerbated by a pretty intense drought and of course the global trend of ever more people. There are simply too many people living in California and it's been a few dry years (and probably many more to come!). It's not really a surprise, and there are probably gonna be more and more places experiencing 'once in a lifetime' droughts and fires as time goes on and everything gets hotter and hotter. No method of managing the resources available magically makes more water appear from dry ground. cwc. ca. gov/-/media/CWC-Website/Files/Documents/2019/06_June/June2019_Item_12_Attach_2_PPICFactSheets.pdf www. laalmanac. com/images4/chart-rainfall-LA-1887-2021.jpg

[@andrewk8636]

@@ZeoCyberG and you know what's worse? Cali pretty much stole all agricultural production from other states. States that actually have tons of water like south carolina. We used to be the biggest peach supplier and now everything is in Cali. Almost as if it's an agenda to make food more expensive 🤔

[@allanvandenberg7]

In South Africa, due to poor city planning, our family has installed 4x5kl (20kl) tanks and now use rainwater exclusively. It’s impressive how much water can be collected in that way.

[@psilocylence]

Some states in the US don’t allow collecting rainwater, even on your own property 🥴

[@ghamerons6287]

We have a rainwater collector in our house at the uk which is always full

[@vile6012]

@@psilocylence Water doesn't just vanish when it lands on the ground. Rain water is essential for filling fresh water sources like rivers, lakes, and aquifers, not to mention watering plants. It's no wonder a lot of states and municipalities, especially those in dry areas, don't want citizens hoarding it.

[@DoctorProph3t]

@@vile6012 they don’t want their citizens hoarding it because they need all that water for their estates and golf courses.

[@thethirdman225]

@@vile6012 Oh brother. What if the only water you collected was rainwater that comes off your roof? That’s how we do it in Australia. Any government that tries to stop that is either out of its collective mind or it’s protecting something (which may actually be legitimate).

[@lockewilliams7329]

I appreciate your positive outlook on low reservoir levels, and that it isn’t always a bad thing. I was in a meeting with USBR back in June and learned that the concern they were looking at, at the time, was the water being below the intakes for the pumps to actually use the water. I don’t remember exactly but I think it was below the pump intakes the time, would have to look it up to be sure. They’re exact words were “we’re looking into it but don’t worry we’re not at the point of considering blasting the dam yet.” Hearing this conversation really brought the severity of Lake Mead’s level to prospective for me.

[@ReflectedMiles]

So the question of the video title was never quite answered--only many of the factors of a reservoir going dry were mentioned. But what does actually happen with the turbines and turbine-related generation systems? What happens to water distribution networks downstream? Do they tend to silt over as flow rates drop well below normal? Do the metal parts and pipes tend to oxidize at a greater rate when no longer submerged? What are the alternatives when the reservoir is massive with high levels of dependency in many communities and in agricultural production? And do we have any example of it happening anywhere near the scale of the subject reservoirs here?

[@sp4nrs]

I’m a hydro engineer. One big issue is the silt gets dragged through turbines and does a lot of damage! As the lake volume decreases, the velocity increases. This disturbs the bottom a lot!

[@toziassmitt]

Seriously. Not only is the title of the question not answered, it’s never even touched upon! This video should be titled very differently

[@MiguelGarcia-vj7oo]

@@toziassmitt that's the whole problem with the lake Mead, everyone keeps pointing out what or how it happened, not what is the solution..... Nobody has came up with a solution......

[@kerbo5918]

I can only assume it was a vague answer because there are so many different types of reservoirs and countless different conditions that affect them. Silt might be a problem in some but not in others. Nuclear coolant reservoirs will have different factors than flood control reservoirs. Etc.

[@LukeA_55]

@@MiguelGarcia-vj7oo I think that's bc there's not much of a solution. I mean think about it, there's millions of people living in a desert relying on one large water source to fulfill their needs. Not very smart if ya ask me I hope I'm wrong but there's not really a solution to their water shortage other than pumping water from somewhere

[@mikefm4]

Gosh who’d have ever guessed tens of millions of thirsty humans moving into a desert could have had such problems🤦🏼

[@sergeig685]

It's not thirsty humans. It's their frivolous water use, like golf courses, unrestricted showers, agriculture, etc

[@harrywilliamson7043]

The population is (currently) sustainable, there has been a lot of strides in water conservation in domestic use. What is sucking things dry is largely agriculture(ie trying to farm in a desert.)

[@staycurious3954]

@@sergeig685 So true.

[@wingracer1614]

@@harrywilliamson7043 Exactly. The Colorado river has plenty of water for thirsty humans. It's growing hay in the middle of a desert or tomatoes in SoCal where it almost never rains that is using up all the water.

[@djsmith5781]

@@harrywilliamson7043 I thought it was this channel that mentioned it, but the only reason california grows water intensive crops like almonds is because of the water rights system that is set up to service holders in order of seniority. So as long as almond growers possess the rights to the first part of the water usage, they have no incentive to use less. The oldest water rights can be bought and sold. It makes sense in a way, to guarantee water for crops that take decades to yield profit, but.. almonds and pistachios are being grown in a time like this.

[@paullukens7154]

I am a retired Science teacher. Your video sets an example for others here on KZbin to learn from... no lies, no exaggerations, no use of 'attention getting' techniques (read: 'BS'). Instead, you present good quality Science in a friendly, easy to follow and straightforward way. Wonderful!! 👍👍

[@mariannorton4161]

Will you do another regarding the consequences of the reservoirs going dry? Best and thank you as always. These are great videos.

[@VPCh.]

Surface reservoirs being depleted are only the start of the reservoir issues we are about to have to deal with. Underground reservoirs that make up 95% of liquid fresh water and the bulk of the water we use are being emptied at an unsustainable rate. They take a long time to recharge and once they empty can become permanently closed due to the soil compressing over them.

[@DanielEShrdlu]

The bit about the Colorado River States encouraging farmers to tap aquifers dropped my jaw. That's a plan like "make it through the winter by eating your seedcorn" is a plan.

[@glennpearson9348]

@@DanielEShrdlu Yes, they are that desperate. Eventually, those aquifers will get so low that the only remaining groundwater will be pumped up from near the bedrock, where the groundwater contains high levels of dissolved solids, mostly in the form of salts. When that happens, the only option will then be to desalinate the groundwater. And, when that happens, you can expect water bills to increase by a half to a full order of magnitude. In addition, since desalination is so incredibly power hungry, you'll also so more power plants being built to run them. And, sadly, because we only seem to understand fossil fuels, those plants will spit more CO2 into the atmosphere, accelerating the very climate change that is causing the decrease in water supplies in the first place. It's an unavoidable, vicious cycle unless we significantly increase our portfolio of renewable energy sources.

[@user-zn4pw5nk2v]

Nah, it's fine, the rain water will just carve a river trough some other unsuspecting city somewhere in india. Don't worry about it, worry about the city when a hurricane dumps a dams worth of water on it and everything it picked up because it got heated by all the asphalt and went up in category. How come everyone is ok with covering everything with 6 lanes of car poo and also having to pay for it, and then be annoyed by the weather it made? be it drought, storm, flood,tornado, flash freeze or heat wave.

[@VPCh.]

@T.J. Kong True, but regions with the hard to recharge ones will be suffering.

[@phhowe17]

@@glennpearson9348 Take a look at the Palo Verde power plant outside phoenix. They are having problems sourcing cooling water. They are currently using reclaimed waste water from Phoenix. Using 75k acre-feet/yr. Fees are expected to increase in 2026. High dissolved solids (30k ppm) require more treatment. Plans to pump ground water have been rejected by the state.

[@looper9264]

I wonder if this lack of water pressure pushing against the dam will cause structural problems? Just asking...

[@Rockmaster867]

I was hoping this question to be answered in this video

[@grumbazor]

Nope. The dam ist build on an empty lake.

[@4stringmanagmaildcom]

It's empty when it's first built and the concrete is at it's weakest. It gets harder with time.

[@andreabuzzolan9807]

Nope. Less water pressure helps resistance of the terrain. Less water diminish the loads on the dam. Less water can develop consolidation, though this is most probably already taken in account when you look to project the foundation without water around you

[@Jreg1992]

The lack of water doesn't normally cause problems but various forms of earthen damns require ground water semi-saturation. Some dirts wont hold water back unless it "is" wet.

[@unspun1YT]

I went to Vegas in the first week of June of this year and it was crazy hearing old people I was traveling with saying that it was missing over a hundred feet of water. Really crazy how this massive reservoir was pitifully empty.

[@brokendownoldman9547]

about 200 feet by now.

[@sandorsalamon4012]

It's always amazing to watch your videos. Every one of them are informative, beautiful, and somehow relaxing :D

[@terricon4]

A lack of water is not normally dangerous for a dam. However... a lack of water in your water pipes can be very severe, even if just for a day. If there isn't constant water and it's pressure in the pipes you'll find the built of mineral layers on the walls can crumble and break off. And with so many pipes being lead (especially in the US where instead of doing expensive projects to replace the pipes early we just raised the allowed lead levels up well beyond the safe point and decided we were now hitting our metrics even as things were) you'll be in serious trouble if this happens in these places. Sudden major changes in the chemical make up of your water can lead to mass poisoning from the water supply. Of lead poisoning and otherwise. If water ever fails in your neighborhood, it's a very good idea to get some lead tests and have a few people around the neighborhood test their water while running it for a bit once it's back. Some utilities would do this themselves... others... don't always....

[@joeyl.rowland4153]

So iffen you ain't hydratin your pipes is gonna rot. Drink yoself lots of water.🤣🤣🤣

[@iamjustkiwi]

We found this out the hard way, we had our pipes freeze for two days and are on very hard well water. For weeks after we couldn't really use the water because all the stuff dried and flaked off; lots of calcium and iron chunks would regularly block our taps and stuff and make it physically risky to drink. Really wish we could afford a softener!

[@barefootalien]

Yeah, this is a really good point... especially with what we know now about the societal detriments caused by lead poisoning...

[@alexyoung3986]

"beyond the safe point" there is no safe level of lead, America is on a mad one

[@austrogalant]

Also if the water in your pipes is stagnant it can lead to biological contamination like bacteria spreading. That's also why you need to size your pipes appropriatly to ensure a minimum flow rate

[@ricardokowalski1579]

8:39 "you are unlikely to turn the tap and not have flowing water" All Latin America falls off the chair laughing

[@WA-qz2gx]

This happened in Australia. Water use was restricted regarding watering gardens and washing cars etc due to drought period. For years now we are at capacity and in many regions serious consecutive unimaginable disastrous floods

[@RockyMillsfatal]

Thank you Destin! We love watching this channel Smarter Every Day! Thanks again!

[@M_W_K]

Can we just talk about how nice Grady is? Despite nearly every episode being sponsored, he keeps the mention to the minimum and pushes it to the back of the video, focusing on the content before all.

[@schmip]

idc i got sponsorblock 😂

[@SupraTompan]

I agree. I can't recommend Grady enough to others. The content is just superb on all levels and to get this content with only a sponsor mention at the beginning, for free? 🤌👌💪

[@palamalama]

Dude, Grady is great for sponsors, don't know what you're talking about. He got me into brilliant...

[@muradm7748]

@@schmip yeap, guilty. I already pay for youtube premium, I don't want more ads.

[@johnbroussard9480]

Very pleasing communication and delivery. Notice there are no impromptu "you know what I mean" s," you know what I'm saying", "at the end of the day", " sooner or later" ubiquitous filler trash talk that permeates what passes for informed delivery in these United States today.

[@thomasrogers8239]

It's dry here in western NY too, just about all my grass got scorched last time I mowed the lawn. Having lived in the southeast there's a certain demographic that moves from one state to another thinking they can still afford to have a grass yard despite now being landlocked and in an actual desert. It was the most asinine thing I had ever seen, there were grey water collection and watering systems for the parks but that wasn't available to the public, and definitely wasn't available where I lived. The issue is we're increasing the water burden of a desert society and we have no ability to replenish it or mitigate the burden.

[@douglascampbell9809]

Up here in Minnesota there is a trend to plant native grassland plants instead of regular grass most people have in their yard. The native plants need less water and the bonus is they are better for the wild bee population. We used to have about an acre of lawn with green grass, Now it's half that. It's only grass close to the house to help keep the ticks from being to much of a problem.

[@EldritchErik94]

Live on Long Island and we haven’t gotten any substantial rain in weeks except for very brief showers.

[@MasticinaAkicta]

Do the golf-fields have gotten their water protection? You know... houses can go dry but the golf fields must always be green!

[@1pcfred]

Yeah it's been unusually dry by me here in southern Delaware too. All the moss on my property is dropping dead. Not that I'm complaining. But normally the moss is pretty lush.

[@Originalxlander]

@Paul Frederick. Get your blades sharpened. You probably have a dull blades and invited infection into the tips of the blades of grass... Which can look like burning. Excited because my Gboard keeps doing auto correction

[@mikesmith4352]

This did help expand my understanding of reservoirs and drought. Here in L A. we are only allowed to water outdoors one day a week and it is quite a challenging shift in lifestyle and priorities

[@user-vp9lc9up6v]

How is doing less more challenging grass is such a waste anyways

[@jackryan4313]

Not what I came to KZbin for...but your voice and the way you convey knowledge...you earned a sub off the first video of yours I found. That's happened maybe 3 times...can't wait to dive into this channel

[@stephenlight647]

This is not the first time that humans have done some very amazing water engineering in the Southwest and then had to move when conditions changed. Moving millions to the desert was always going to produce an issue.

[@DianeHasHopeInChrist]

Yep....deserts are to travel through...NOT live in permanently. The selfishness and greed of Casinos and mindset of those Vegas entitled, uneducated, lazy fools has made it where they destroyed themselves. Watering grass that has never belonged in the desert is pure ridiculousness. Such a huge waste of water. AND.....Vegas is sitting on top of a HUGE Magma Chamber. Lol. Hope all of Vegas sinks into it.

[@FW-jq1ox]

Humans migration isn't efficient with resources - we're not good at that. Anyway, migration to the SW would have been fine except that millions became tens of millions because we are good at something else.

[@scottmantooth8785]

*true...you've altered/damaged (if not destroyed) the local environment balance of both flora and fauna irreparably...only to discover that "oops, not such a good idea after all*

[@craigb8228]

As Southwest U.S. Real Estate increases in value. WHY?

[@kitefan1]

@@craigb8228 No Snow.

[@rreagan007]

Who could have imagined that growing crops in a desert could turn out badly. I guess we'll just have to go back to growing crops where it actually rains.

[@spnyp33]

...or evolve our farming/irrigation practices. IT involves more infrastructure and planning, but you can water at the roots as to not loose so much water to evaporation. I've done it in backyard gardens, though it might be difficult to do on a large scale operation.

[@scotchsoda3165]

That way we can go back to pickling food for winter. Having fresh produce in winter is over rated..........

[@user-zn4pw5nk2v]

@@spnyp33 evaporation is not a problem under a steamy greenhouse, but heat is.

[@chunkmen]

@@user-zn4pw5nk2v Evaporation is an incredibly bad problem in greenhouses because it raises the humidity so much that the plants stomas clog and will eventually "drown" on top of the issues of it being unsafe to work in said greenhouse and not including the mold issues that come from near constant 100% humidity.

[@user-zn4pw5nk2v]

@@chunkmen but you wouldn't lose water, just saying, and having shade will lower the maximum humidity from heat.

[@barbsfpv3066]

Great video. I live a stone's throw from Oroville Dam in California, and have lived in this area all my life. It gets irritating having to constantly explain to people that our reservoir water is intended to be used, so they start out full (usually) at the beginning of the year, and they're empty by the end of it. Because we don't see rain for about 7 months of the year here. Most people assume that reservoirs are pretty lakes, and if they're empty or only partly full then we're "failing" somehow. So it was nice to see somebody who actually gets it. Thanks!

[@demef758]

Hey, I have a great idea: let's import another 10 million people from south of the border. Diversity-through-illegal-immigration makes us stronger, I have been assured.

[@combak2712]

Out of curiosity, have you done a video on what happens to the area that gets submerged as a reservoir fills? Like, soil erosion predictions, what they do about all the trees, etc. Also, have you done a video on dam removal?

[@matthewcarver2013]

I think he supports the status quo when it comes to our current water infrastructure systems. Desalination could easily replace them but that's somehow "impractical".

[@rhys5567]

Like Jindabyne which was entirely flooded by the Snowy Hydro Dam. Which now employs 600 people whilst Jindabyne has a population of only 2,600. Sounds terrible. Plus producing clean power for decades. Shocking.

[@combak2712]

Guys, I'm just curious about the logistics behind removing a dam and the sort of things they have to look into when decided whether or not to do it. Let's not make this political, please. As for the first part of my comment, I was just visiting one of those lakes in Tennesse made by damming a river, and I started to think about what exactly was under the water and what it'd look like if it drained like Lake Mead has.

[@sasukedemon888888888]

@@combak2712 i can't remember the name, but about an hour from where I live is a great fishing spot because there's tons of underwater structure for fish. The thing is, that underwater structure are houses, cars, roads, and other buildings. Because it was a very old town that had been intentionally flooded during the construction of a dam. If I remember right, the town had a very low population and the government paid them all to move. If I could remember the name, I'd look it up.

[@mehere8038]

@@rhys5567 and how about you talk about what happened to the river system below the dam & also what happened when they released masses of water, purely for the purpose of flushing out the muck & restoring the river system, due to the massive environmental desegregation that had occurred due to the damming it. I guess you'd rather just block your ears to anything you don't want to hear huh?

[@someolddude7076]

“A reservoir doesn’t creat water, it just stores what’s already there” A concept that still escapes many people in power, leading to bad decisions, and here we are today.

[@Prototheria]

We have idiots here in UT saying, "wull, they just need to build more reservoirs." 🙄

[@jarnecolman4761]

Reservoirs even consume large amounts of water due to an increase in evaporation because of the increased water surface. Besides reservoirs placed directly on rivers have huge ecological consequences, which might turn into economical consequences due to lost ecosystem services like the disappearance of migratory fishes, and slowly fill up with sediments making them lose capacity over time. Large dams on rivers never were and never will be a sustainable solution in the long term.

[@jth_printed_designs]

@@jarnecolman4761 Humans having water is a larger priority than the lives of migratory fish. Minimize environmental impact when possible, but the wellbeing of humans is paramount.

[@themonsterunderyourbed9408]

@@jarnecolman4761 that's kind of an idiotic thing to say. No matter what, that water will evaporate. Whether it's in the reservoir or downstream (in the lake or body of water it ends up in).

[@jarnecolman4761]

@@jth_printed_designs i agree that supplying humans with water is important, but quite often there are other options possible besides just putting a dam on a river and creating a reservoir behind it. Especially when it comes down to larger rivers. Besides, sediment entrapping by large dams is causing huge issues in downstream communities. Normally erosion in the lowlands and delta's is at least partially mitigated by sediment influx from upstream. Dams block this influx, causing loss of land downstream. Large dams and reservoirs can also siltation in delta's (which is happening right now in Egypt) because of a lack of freshwater supply. So it's far from just an ecological problem.

[@WoddCar]

There were 2 big problems when the Colorado River dams were built: 1: when the dams were built, they made the projections on water that would come into the lakes based on the climate of the 1900s which was above average, so in the drought of the 2000s, the lakes would be very under capacity 2: the dams were built to accommodate the population of the mid 1900s, but since the population of the southwest has grown very much, consumption, especially agriculture, has been higher than the dam was built for

[@martylost167]

You can only made a dam so big. It's simple math, topography, and geology, but more of the last two. The people in the area are just using the water to fast and have to quit. No green grass, fountains, swimming pools, water parks, etc. and have to start conservation now. Gones, gone and if it's "All Gone!", time might not bring it back.

[@beepbop6697]

Brilliant idea to build farms in Arizona and Nevada. 🤦

[@WoddCar]

@@beepbop6697 yeah, just like those ones in the middle of saudi arabia

[@chiefsilverback]

There's a third even bigger problem, the Colorado River Compact allocates more water than the river has ever supplied!

[@HyperSpaceProphet]

Add in the mismanagement for the past 50 years, letting the upper dams feed water to Lake Mead (which is the only one that has levels in the treaty) and you have what we have now...they let it go too long, drawing down the upper Colorado lakes to feed the lower, hoping that there would be a change in the inflows. There wasn't, so we now have the situation we have today.

[@mr.iforgot3062]

I've been best friends with this man for 26 years. Im proud of that. Give me a shout out Practical Engineering! Yeah! Let them know Im serious!

[@maleieads]

Maybe it's just me, but I'd like to know how the desalination plants work, and why we use the type of desalination we do. (Reverse osmosis vs evaporation (boiling, then condensing)) I think it'd be an interesting idea for another video.

[@plusafdotcom959]

You can probably find answers to those questions with a few web searches for keywords. Some of the issues that drive those decisions are local approval or refusal, energy costs (efficiency of a process) and things like location. (nobody would like the plant on an earthquake fault line, or close to a scenic or natural preserve, etc.

[@bluemond5329]

Extremely polluting with gigantic amount of salt spread around.

[@marvinyo5]

They definitely need to look at pumping the sea into reservoirs for the future Maybe with minimum filtration to remove and recycle the snow The solutions are there as they build pipelines for oil and China is already building a water transfer to high altitude rivers to continue the flow for their electric dams Also will control rising sea levels as water is transferred in land

[@washemoamadah4706]

@@bluemond5329 Dont they just return the salt into the sea?...

[@kitefan1]

@@washemoamadah4706 it makes the local salinity too high for the local sea critters. This is a problem with Arabian peninsula.

[@Jacob-yg7lz]

One thing you forgot to mention is that, if a dam is also a power station, low water levels may force them to shut down their turbines due to insufficient flow.

[@1.4142]

He did mention that the hoover dam will not produce power if water levels drop another 100 feet.

[@donaldindividual-1]

Lake Oroville did in 2021. It’s going to be drastic in Vegas and Phoenix, imagine 110 degree heat and no power!

[@sergeig685]

@@donaldindividual-1 They have unlimited sunshine that can generate electricity from. But the derps don't believe in solar power

[@SenileOtaku]

@@sergeig685 Solar power, in it's current state, is only good for *augmenting* power generation. And trying to use centralized solar power generation will take up a lot of land area. Solar works best as a highly-distributed system (like putting a panel in your back yard or on your roof to augment your OWN supply) or even more portable electronics having solar cells. Maybe even solar panels on electric cars to top-up the batteries (it won't be enough to power them). Future energy sources will have to be a wide variety of options, with no singular source winning out. But complex ideas are too much for the far-left to handle.

[@sergeig685]

@@SenileOtaku Sounds like you have never been to Nevada and Arizona. Empty desert land is something they have in great abundance. In fact enough to power not just the state but the entire US of A. I have solar panels on just the portion of my 1400 sf roof and my power generation surpasses my consumption, even with the electric car that we drive. Of course there is no solar power at night. But the demand for electricity after sunset is basically half that of business hours. This is when the hydro and coal can be scaled up if necessary. I'm not even going to mention power storage, since it is not cheap at this point in time. If you think this is a complex idea, then I'm even more saddened by universal suffrage rights.

[@hkh4-onehandedvidya]

Living in a state that rains enough all water is groundwater drought is bizzare to me I can only remember one time in my life we had a drought

[@chrisvincent8123]

The optima Lake dam is a good example of how ground water effects surface water. If the ground water level is not higher than the stream water level, then the stream water will just soak into the ground. This same effect is probably effecting the dams along the lower Colorado River.

[@Rnazzaro]

When you watch the time lapse videos you can see the cities growing around the reservoir as the reservoir shrinks. I would say that has something to do with it also not just the drought.

[@adrianjohnson7920]

"Build it, and they will come". Everybody wants to live near a lake and own a boat . . .

[@lrvogt1257]

Yes. All of the above. Too many people using a diminishing resource.

[@KeweenawPatriot]

It's because of all of the golf courses. They use 300,000 gal of water a day each. Get rid of them and everyone will be fine.

[@lrvogt1257]

@@KeweenawPatriot : That would certainly seem like the first thing to go though golf is a huge reason people retire to warmer climates.

[@specialestness]

@@KeweenawPatriot Los Angeles by itself uses of 524,000,000 gallons of water a day. Eliminating golf courses would be a drop in the bucket.

[@edwardblair4096]

I thought we would hear more about the physical conditions of dams and related systems when the water trapped behind it disappears. Are there any dams that become unstable when the water they are designed to hold back is missing, or if the surrounding soils/rock formations are exposed to the atmosphere and dry out? Are there problems with silt that has collected behind a dam that had been in place for decades when it gets exposed to air? I know there is a problem with toxic dust blown off of the lake bed of the Aurel Sea in Central Asia as it has almost completely disappeared. Won't there be a minimum level in a reservoir that can not be drained below? I was hoping to hear more answers to these types of questions.

[@Electronic424]

I bet if the concrete had fully cured the bow shape in dams could be an issue if water levels became too low, good thing it would take a dam like Hoover dam 1000 years to fully cure.

[@mcodyw]

Yes, that’s what I thought this video would be about.

[@lrvogt1257]

@@Electronic424: Good point but isn't there some rebound of the underlying ground that could simply lift that side of the dam causing unplanned stress points?

[@beeber4516]

@@lrvogt1257 I don't think so because the stability of the dam was already factored in as a dry structure.

[@lrvogt1257]

@@beeber4516 I appreciate that but the ground beneath and behind the dam will move which could put torque on the sides. Maybe it won’t matter.

[@Avalanche2]

The odd thing is the continued development of cities in the desert and the draining of the Colorado river for agriculture is the real problem and nobody EVER mentions it. Human consumption is a small fraction of water use in these waterways.

[@Anomize23]

THANK YOU SOMEBODY SAID IT!!!

[@twitter423]

Live right next to Optima Lake and have always been curious why it never filled up. Awesome to see it mentioned here.

[@eirinym]

One thing I think that gets overlooked a lot is not just reservoir levels, but groundwater levels. They've been depleting or low for a long time in many areas of the plains and the western US. But aquifer storage, which is used in some places to store additional rainwater runoff may be an option to help bring the water table up higher and prevent as much evaporation from the surface and reservoirs.

[@danielrose1392]

Few years ago they started pumping the water from the treatment plant into a forest instead of discharging it into the river. This way the aquifer is filled up constantly over the year. Once river levels are low in the summer, the water still goes directly into the river. At least here this works much better than trying to use rain water, because it's a constant supply.

[@tommurphy4307]

NAME ONE PLACE WHERE SUCH STORAGE EXISTS

[@tylerhayslett9073]

Reminder that John Wesley Powell told us there wasn't enough water out west more than one hundred years ago and accurately predicted rainfall and sustainable population levels.

[@PROVOCATEURSK]

Looks like nothing can stop capitalism now.

[@phillipdarling2642]

As a person that looks at low water levels in reservoirs, I’ll now be differentiating from the perception of lack of accumulation in a lake. Using the capacity in a reservoir is very to the point.

[@crankychris2]

So is running out...

[@Skinflaps_Meatslapper]

You should take a look at the OC Fisher reservoir in San Angelo. It was planned to be far larger than it is currently, but they misjudged the river inflow and it never got close to reaching capacity. Old boat ramps and camping areas by the projected shoreline are abandoned in what has now been converted to a state park. It still holds a small lake, maybe a section or two in area depending on how wet of a year it is. I guess it's good that it's there in case of flooding?

[@davidbehrend7054]

OC is now pretty much a protection reservoir in case of flooding. I was going to comment the three dots in Tom Green County, only one of those is “normal”….Nasworthy, which is pretty much a recreational lake, and usually is kept at a standard level.

[@Skinflaps_Meatslapper]

@@davidbehrend7054 Howdy neighbor lol Twin Buttes isn't much larger than OC but levels are usually more reliable and very rarely a puddle. If they had their way, all three would stay filled, but as it stands they're really only able to regulate Nasworthy by drawing on Twin Buttes as needed, the water supply just isn't there to support them both in drought conditions.

[@davidlivermore5392]

I'm curious about a second competing process that happens when these reservoirs dry: evaporation. Evaporation would be quite different compared to simply letting some water out because it would leave behind chemicals that didn't evaporate, as the lake decreases in volume, concentration of those chemicals could increase. This was a reported issue in some other reservoirs that dried up, they left behind dusty beds with dangerous levels of carcinogens (or at least suspected carcinogens).

[@ScruffyCityFishing]

I think this happened in Russia. Can’t remember the name, but it’s a wasteland after a lake was eliminated by poor planning.

[@BerraLilltroll]

@@ScruffyCityFishing Aral lake?

[@ScruffyCityFishing]

@@BerraLilltroll I think that’s the one. I watched a video on it from another well respected creator a while back.

[@danl6634]

Salton sea says hello

[@essr4580]

@@BerraLilltroll also karachay

[@JamesOKeefe-US]

It makes me very happy to see this trending. Good, educational content. Love it! Thanks Grady, great work as always!

[@KevinDC5]

One of your best episodes! I really enjoy the way you present these engineering topics with rational, concise, fact based explanations. Especially in these current times where many minds(unfortunately),tend to process complicated subjects through emotional presumptions based primarily in factual error.

[@tamnguyen-bl7jf]

ok

[@Emppu_T.]

Yeah

[@BeasoreBilly]

Agreed!

[@SomeRandomDevOpsGuy]

I dont' think anthropogenic climate change is a factual error

[@Murtazaht]

You, my good sir, are a gem. Keep up the good work!

[@danielmuzza5125]

It's a very interesting topic, thank you for sharing it. Unfortunately, what you actually discuss is pretty much what is happening in the city of Monterrey, Mexico, where I'm currently living. The city's population has grown severely, as well as the surface area of the city. However, one of it's main sources of water supply (Cerro Prieto Dam) has now become dry, and another dam has a historal low level (La Boca Dam, around 8% of storage). Only one out of the three dams currently under operation has a relatively decent level. To make things worse, the shallow wells that provide around 40%-50% (some of which have been activated due to the crisis) are running very low levels now. Many people of the city's 5 million inhabitants are no longer receiving water from the grid for days and weeks. I hope my friends from the US Southwest start taking care of their water and reducing their water consumption. Day Zero is completely undesirable.

[@jerrymiller2367]

You're only missing the water that nobody wanted anyway . . . sorry, couldn't resist that, apologies for bad taste. But seriously, I wonder how far south this drought goes. Guatemala, Panama, etc. are largely tropical rain forests so they must still get a lot of rain. The solution might be in de-salinization plants on the coast and then pumping the water inland. And pump the desalinated water into the existing reservoirs to form a supply buffer so in case a desalinization plant stops working, there will still be a water supply in the already-made reservoirs.

[@Harry-zz2oh]

I live near Las Cruces, NM about 70 miles from Cuidad Juarez, Mexico. We use the water we have been allocated, pump from an aquifer if no water is available from the Rio Grande, and conserve as much as possible. Conservation is needed due to the high cost of electricity to pump the water and the increasing depth of water to be pumped. A good part of my land is planted with pecan trees and other fruit trees (peach, pear, plum) and the groundcover is bermuda grass, which survives very well in the high heat we have. I hope your water issues are resolved during this monsoon.

[@Exlaxius]

Desalination and transport of said water is a lot more costly than one might imagine. I hope they look more into zero output systems. A zero output system, such as is in current use in Phoenix in the western US or Cary, NC on the east coast send all treated water from their waste treatment system into a reclamation facility and then to the water treatment plant. In essence what goes down the drain can hit the faucet in 36-48 hours. These type of systems eventually prove to be cost effective since the reclaimed water is cleaner than the water taken in from the environment requiring less chemicals, filters, etc at the water treatment system. This massive reduction in what is being pulled from natural resources allow the decreased rain, etc to accumulate and recover during season of low precipitation.

[@tommurphy4307]

DAMS DON'T CREATE WATER- they simply provide flood control- HOW MANY OF THOSE 5 MILLION PEOPLE DROWNED IN OR LOST A HOME TO A FLOOD??

[@valle3452]

@TNerd Even with rationing, which other cities in northern Mexico have been doing for decades, water reserves in the region are reaching historic lows. Hotter, longer summers are also not helping. It will get worse before it gets any better.

[@LazyLifeIFreak]

What Ive found to work in my backyard farm is to use weeping hoses, sun shielding in the form of a semi-transparent fabric over a folding arm during the hottest hours of the day and covering the soil to reduce local evaporation. It might not be feasible on acres and acres of mono-crop but for me it seems to be a worthwhile investment.

[@1pcfred]

The technical school is doing research around the corner from me about farm irrigation. This year they're getting pretty good data because it's been drier than normal. Feasible or no, we have to do something. Most here use pivots to water with. Which are not the least wasteful way to water. Probably the most wasteful.

[@keco185]

It’s recommended in dry areas to use straw, mulch, pebbles, or another protective layer to prevent evaporation and to water plants at night so the plants can absorb the water before it evaporates

[@ClariNerd]

What also works rather well is not farming in a desert

[@keco185]

@@ClariNerd what works even better is not living in a desert at all

[@justsomeguy6474]

@@keco185 Living in a desert is fine. There's lots of water for people. It's agriculture that uses almost all of the water.

[@sierrabravo7368]

It's amazing how fast large dams that are critically low can fill up. in East Coast Australia (Sydney) our largest dam Warragamba dam went from 10% to nearly full within a few days after 100mm or 4 inches of rain then a couple of years later 4 floods in a year on that river system

[@Kirinketsu_]

It took it something like 4 years to "fill" back in the 30s

[@peepeetrain8755]

my local dam in northern nsw was at 1% in 2019. end of 2020 it was 100%. luckily this dam wasn't used for humans but purely agricultural uses.

[@Rookie-2552]

That dam is quite annoying lol! We need the NCR and Legion to set up on it!

[@autumnlove7931]

An interesting watch. Thanks for expanding my mind!!

[@michaelrunnels7660]

I see the problem of water storage as having two major components: water supply and water demand. This video addresses water supply only. A drought exacerbates the water storage problem when demand increases significantly. When Lake Mead was built, the water demand was fairly low, as Las Vegas had a population of 39,000 people and there was no agriculture in the area. The water demand for the area Lake Mead services has increased more than 10,000 times. This has made all the calculations made when Lake Mead was built, meaningless.

[@antcommander1367]

sadly it's just not that. in 1st place colorado river compact (1922) allocated some 15 million acre feet of water, but colorado river only carriers around 12 to 13 million. also they knew from start that this was going to be problem in future, john wesley powell warned in 1893 ''theres not suffient amount of water to supply these lands''. which BS didn't stop there few year back ''states force modelers to add magic water, extra water which only exist in computer models only''. so american west is like ''little girl living in imanegery magic land for last 100 years, and now she has to accept harsh reality''

[@martylost167]

And that is why Lake Mead will drop an estimate 20-25 feet next year.

[@ChristianLaurinE]

BINGO and this is why I really detest white washing like this video. This lack of water in the South West was predictable even 40 years ago. But hey serves the South West right! But let's blame climate change right? Not saying it is not a factor, but let's keep it in perspective.

[@brianforbes3599]

Ya LV has grown so much, however the huge majority of the water rights/usage to the Colorado River belong to Cali.

[@michaelrunnels7660]

@@brianforbes3599 Yes. That's where most of the agriculture in the desert is done using Lake Mead water, right along the California/Arizona border. Turning huge areas of the desert green takes a LOT of water. Nature doesn't do that kind of thing, but we do.

[@DianeHasHopeInChrist]

You are a wonderful teacher! I loved your professional, factual, concise, and clear explanation about Dams, Reservoirs, Aquifers, and ground water. Excellent! Thank you!

[@tamthuong4048]

ok

[@richhughes2225]

Good video. Thanks. Advantages of water projects are often clear. "Basic human need" does not include watering bluegrass lawns, Las Vegas hotels and casinos and decorative fountains. Reservoirs not only leak and encourage loss through evaporation but, like Lake Powell, destroy incredibly beautiful canyon systems.

[@garrickanderson5204]

Colorado has been getting a ton of rain since this video was posted, so hopefully some of the water starts getting down stream to the reservoirs! It made me incredibly sad flying over Lake Mead back in May and it's only gotten worse.

[@hygrometer]

barely...

[@hygrometer]

you shouldnt be sad, you should be angry

[@brokendownoldman9547]

What water Lake Mead got from the monsoon rains will go into the dry ground 1st, that's why the water level won't rise anytime soon.

[@jimmym3352]

update, that rain didn't last long. We got a lot in July in Las Vegas, but almost nothing since. And really snowpack is what we want. And yes snowpack has been good so far this late fall, but the same thing happened last year, and after initial snow falls, very little fell. And we are predicted for another La Nina year like last year so...

[@EricBaggsTharsos]

This was really cool to see, I hear so much about dry years and reservoirs but I never realized the absolute massive scale it would take to respond to YEARS of drought! There are a couple of issues with looking at projects on these massive scales. I really hope that you decide to revisit this topic from the perspective of building these things in unique environments. Environmentally speaking, for example, a steady consistent flow of water might actually be a very unfortunate flow regime for plants that use flood waters or signs of drought triggers (or fire) to influence their reproduction. Especially long term and when the area is faced with novel species over time and human transport. Civil engineering projects that aren't successfully mitigating environmental impacts or ensuring proper operation and maintenance pose a hazard to so much life in the long-term. I really think it's super important to frame the environment as integral to design and planning, not just an afterthought for somebody else!

[@tommurphy4307]

after all that wordiness- the dams were a huge success regarding the main reason they were created- flood control. is that environmental enough for you??

[@bwhog]

Another dam that largely failed to fulfill its expected utilization is Coolidge dam (which forms San Carlos lake) on the Gila river in Arizona. The lake has only ever been full once in its now nearly 95 year history and is rarely above 10-20%. To see the size of the spillways on this dam and the volume they were designed to cope with is comical. The dam itself is actually a pretty elegant and fairly attractive structure but engineers vastly overestimated what would be available for storage, especially with upstream diversions as far away as Safford and Thatcher near the Eastern border of the state. Also, it should be pointed out that flow rates of the Colorado river were *significantly* overestimated when water allocations were made and you'll never get anyone to give up a water allocation because of how important water is. Originally, it was intended that there be enough water flowing downstream that it would still reach the Gulf of California. Doesn't happen. (Mexico diverts what little water does pass through a short distance south of the border.) Drought/flood conditions are a constant cycle in the Southwest. In fact, in the 1940s, Roosevelt lake, which serves agriculture in the Salt River Valley (Phoenix metro and particularly the East Valley area) actually did go basically empty. Biggest floods ever in the valley were at 1891 and (somewhat less) in 1905. (Records prior to that point are scant and only anecdotally go back to 1833.) The measurement of the Colorado's "average" flow was taken during a period of unusually wet years (oops!) and that's part of the reason that Lake Mead has never again been full since the winter of 1980, population growth combined with over allocation and cyclic drought conditions reemerging.

[@michaelt.9372]

If its regularly at a certain level, wouldnt the regular level be its full level? If its only been a certain level once, wouldnt that be an overfull level?

[@keyboarddancers7751]

*@bwhog* Absolutely spot on! Hoover Dam was built on the back of entirely erroneous data and historians will look back on it as one of the greatest hydrological engineering mistakes of all time second only perhaps to the catastrophic Banqiao Dam disaster of 1975.

[@12tman12]

@@michaelt.9372 No, that would be it's regular or average level, whether that level was intentional or not. Full means it's designed full capacity, you don't change the meaning of a work like that just because it isn't normally. Does the top speed of a car change just because it's never been taking to that speed?

[@michaelt.9372]

@@12tman12 i suppose youre right

[@weinteruptth.1479]

Hi from safford :) neat info

[@utkarshgoel7873]

Thanks for sharing such wonderful information 😀

[@JulieWallis1963]

I’m not an engineer. I have no _real_ interest in engineering, but I do love learning about bridges, dams, reservoirs etc because Brady makes it fun and interesting with really high quality videos and wonderful footage.

[@dandy9412]

Hey kids, Captain Obvious here. Do not move to a desert with millions of other people and expect a never-ending supply of fresh water. You're welcome.

[@Guysm1l3y]

Populations aren't the problem with water usage in arid climates in the southwest, the vast majority is used by non-residential consumers (aka agriculture and industry).

[@michaelhebeters9568]

@@Guysm1l3y ya right

[@scottjuhnke6825]

Thanks for what you do. Really appreciate you putting an understandable face on complex issues.

[@ZackTheKack]

My question is this: despite being in a drought (i think most natives in the southwest will recognize that we've been somewhat drier than normal for a good while), doesn't it seem that the popularity and exponential growth in the southwest, in places like colorado, LA, Vegas, etc. Is finally forcing people to see the reality of this location? Like, yes, i get it, we try to make sure we cover all bases all the time, but at the same time.... this is a desert. Really, most of the SW is at least a semi-arid desert. Many places are high above sea level and very dry. These are just realities. Ones we seem to have tried avoiding.

[@gorkyd7912]

There's massive rivers flowing through so I don't know what your point is. I don't see how the reality of living in a desert is different than the reality of living anywhere else. The world is inhospitable, we only live here through constant labor. Dealing with whatever water inflow or lack thereof is just another problem that survival requires a solution for. "Normal" water amounts is just some arbitrary value, there's no validity to declaring some certain amount of water to be normal when the reality could be it was an average derived from an exceptionally wet weather cycle for all we know from our mere centuries of study.

[@banginbadger75]

@@gorkyd7912 Humans were never meant to live and survive in a desert I think is what he's trying to say.

[@jz94117]

We need a pipeline from the Mississippi River to the Colorado River. Too much water is going to waste in the Gulf of Mexico.

[@gorkyd7912]

@@banginbadger75 Yeah. And I can make the same argument for anywhere else on earth. But actually it's just lazy humans; lazy humans are not meant to survive on earth.

[@tommurphy4307]

theyre all moving to east texas were they will have blizzards, tornadoes, power blackouts and water shortages.

[@bludog4657]

Thanks for putting this out.

[@coug96fan]

Great summary! Living in the Pacific Northwest, we see a lot of water over the year and are blessed with multiple dams to create water storage and inexpensive power. But it only takes a dry month and we turn into a tinder box. Water capacity of the land and rivers is a fascinating science and one we need to understand in broad view of where we live.

[@catherinerosner970]

Totally agree! I live far northwest WA. Moved here two years ago from OK. The difference in the temperatures and natural resources is no contest. I have found heaven on earth.

[@jons787]

There’s good reason the PNW has been called a climate change refuge.

[@dirkjefferson6202]

@@catherinerosner970 give it another 10 years. your body will lose the ability to produce vitamin D and you'll develop never ending case of depression. but at least you will be moist. :)

[@pkbrown58]

Please keep us up to date on Lake Mead and other critical reservoirs while providing more details of what city governments must do (and are actually doing) to mitigate these crises. Thank you!

[@nenmaster5218]

Seen 'Water Wars' by 'Second Thought? And Some More News covered 'Were running outta Water!!'

[@dr4d1s]

Google is a good way to find information that you are interested in. I highly doubt PE is going to do multiple videos on this topic/issue.

[@michaeld5888]

The world over the must do is for political manifestos. Will do is for fantasies.

[@tommurphy4307]

@@dr4d1s really? there are hundreds of them on YT- and just on lake mead.

[@darksu6947]

Here's your update! They're screwed in the long run unless it suddenly starts to rain everyday.

[@Tx_P71]

The city of Dallas has water rights with multiple lakes here in North Texas. With that being said most water usage is from them not the other communities around the lakes. And honestly that's a problem. My lake, Lake Tawakoni is already a foot and half low. We haven't seen measurable rainfall in almost 3 months. The dam, Iron Bridge Dam is a set spillway. It does have 3 gated outlets, S2; U2; V2. but they both are not controlled. The dam: 85ft tall. 85ft structure. 85ft hydraulic. The drainage area for this dam is 752 square miles. This is where the start of the Sabine River happens.

[@PatricenotPatrick]

Yikes. Hope y’all get some soon houston has rained a bit for 3 days here but we need more

[@Mircea020]

I don't need Brilliant. I just have to be a subscriber to your channel. I never knew how fascinating civil engineering can possibly be till i came across your channel. Grady , never stop being amazing !

[@TilmanBaumann]

A lot of dams also lose capacity over time from filling up with silt. That is another good reason to plan dams with seemingly over-capacity.

[@jerrymiller2367]

And they should dredge out the silt now while the water level is low.

[@tommurphy4307]

glen canyon flood control removes the vast majority of river silt before it gets to mead. there are areas in lake mead that have a few feet of silt (you saw that boat sticking up out of the silt) but thats really nothing.

[@boneheadd911]

Can a dam be damaged by lack of water? Such as dry soil, pressure change, etc?

[@Pon1bcd]

Assuming Dams were built like Hoover Dam, without all the water. They’ll be fine without it.

[@PracticalEngineeringChannel]

Usually not unless the lack of water happens quickly (called rapid drawdown).

[@ZaHandle]

They’re built dry so they should be fine

[@MrMatteNWk]

@@PracticalEngineeringChannel So what happens in a rapid drawdown? Does dam asplode? :)

[@gantzm]

@@PracticalEngineeringChannel How does this impact earthen dams? I'm assuming earthen dams are usually "dry" via drain pipes or seepage or something. But if they contain a certain amount of water and that water suddenly finds itself at a higher pressure than the outside things are going to go bad really quick. Or is this condition creatively engineered around somehow?

[@joshuagarner1654]

You forgot to mention 1 big issue about some of these damns, they are hydroelectric dams that need a certain level to operate. And we are getting dangerously close to that level

[@brokendownoldman9547]

With the technology we have today, they could create hydropower turbines to work in lower water levels, you'd think?

[@rickshawwheelchair]

This channel is great because he gives most all of the facts from all sides without politics. I appreciate that, thanks, PE

[@TimChuma]

Similar happened to the supposed "drought buster dam" (was a headline for this in the Sun newspaper 1983) after the Thompson Dam in Australia. By 2009 it was almost completely empty. Below 36% they could not even take water out of it. The state government ended up comissioning a desalination plant for long term use.

[@SenileOtaku]

A lot of coastal cities should be implementing desalination plants. Would certainly like to see NYC start doing that so they stop stealing from "upstate" counties and trampling over THEIR rights.

[@jayjaynella4539]

That $5 billion desal plant was built on flim flam evidence and has not been used since it was built 18 years ago. If it was started now, half the users of power would be without power due to the huge electrical demands of desal plants. Water levels now at highs due to forcing all Victorian industry to dragon country. That desal plant costs every Vic water user $600 a year. No droughts in Vic for several years.

[@TheBelrick]

@@jayjaynella4539 imagine a world where Aussie politicians are both competent and pro australian. In such a scenario there would be a nuke plant to power the desal and green that part of Australia while also keeping Aussie for Aussies minus the Tyranny .

[@johnknightiii1351]

Great video. As a Vegas native seeing people panic without really understanding the situation is a bit frustrating. Even at its current level lake mead is one of the largest reservoirs in the country and it is currently serving as a buffer for upstream and downstream. Some people think the water is getting used up by the golf courses or people in Vegas but in reality Vegas uses almost half the water we did 20 years ago while doubling the population. The southern Nevada water authority has been monitoring the situation closely and has several contingencies in place for the valley. The first is the 3rd straw which will allow over a decade of water even when the dam reaches Deadpool even if the upstream dams stop releasing any water. There are other plans like paying California to desalinate as a trade for some of their allocation (they use the most for agriculture). They also have plans to pump water from the other valleys in Nevada, most of the state is unpopulated and empty with huge underground reservoirs that could supply Vegas with enough water for decades. Right now Vegas still has some of the lowest water rates in the country, especially when your usage is lower. The SNWA isn't just sitting idle waiting for the collapse of Vegas like some would believe.

[@jacobvardy]

I've been watching this from Australia for fairly obvious reasons. My understanding is that the big problem is Phoenix. Which has terrible water usage. And a property bubble that kinda relies on terrible water usage.

[@johnknightiii1351]

@@jacobvardy although Phoenix isn't as efficient with their water usage lake mead has been keeping them supplied by sending water down stream, they get their water from the Havasu area that is downstream from Hoover Dam and lake Mead. That lake is almost at full pool. The actual water hogs are the agriculture farms in Arizona and California. They are using the Colorado River water to farm in the desert and are using more and more water every year.

[@roberts.4034]

@jacobvardy Researcher here… Surprisingly, Phoenix finds itself in a similar situation to Las Vegas in this regard. Indeed, the entire state of Arizona uses slightly less water today then in the late 1950s, when the population was under one million. The population today is over seven million, to put that growth into perspective. There are numerous reasons for this, from the 1980 Groundwater Management Act (which formed “Active Management Areas” out of Phoenix, Tucson, and the other major urban centers and forced them to develop century supply water guarantees with projected growth included in their analyses) to the reclamation of former agricultural water allocation. Coupled with AMA efficiency mandates, these managed areas use water, like Las Vegas, far more efficiently than cities outside of the American Southwest. These policies weren’t foolproof, and unscrupulous developers (of the type you’ve probably heard of) have exploited loopholes in the non AMA areas on the outskirts of Phoenix, Scottsdale, Mesa, Chandler etc. to develop in county islands with essentially unregulated ground water usage. Naturally, the tremendous windfalls from the pre and post COVID housing market bubbles have reduced the political will of the previous decades to restrict these developments, but as a recent NYT article pointed out, these developments have essentially run out of groundwater and lack the legal leverage of the main cities to negotiate new allocations (just another reason to pay municipal taxes I suppose). In spite of all of this, it’s worth remembering that industrial agriculture, including significant and nonessential allocations to crops like livestock feed, cotton, almonds etc. consumes around 75% of Arizona’s net water supply, so even marginal cutbacks here could dramatically increase municipal and industrial supplies going forward. Perspective is crucial, though, it’s no longer enough to simply maintain the current allocations, and efficiencies must continue to increase while usage decreases as Sonoran desert living has always demanded of its inhabitants (from the Hohokam to today). All this is to say that solutions, while perhaps not politically expedient, already exist to many of the world’s water crises, but only if we act to implement them with all due haste.

[@johnknightiii1351]

@@roberts.4034 Awesome information about the Arizona area. I appreciate you responding here and sharing.

[@billferner6741]

Pumping underground water in Nevada? Nevada is big, but I would check the pumped water for radioactive contamination anyway.

[@tomroddy5920]

Nice to see the reservoir continuing to provide water. It’s doing its job.

[@JayJayGamerOfficial]

Hwre in Australia we had a similar problem, all the resoivers here in Sydney were all below 20% in the peak of the droughts and fires of 2018/2019 and not even a year later they were full and spilling a few gigalitres every day

[@ThePsiclone]

Be an interesting (to me at least) topic to know the effects of water level changes on the structure of a large dam like some of those you featured. How does all that concrete drying out affect things? How much does it all move with the relief of pressure against the wall, things like that.

[@jaredpatterson1701]

Yeah this video needs a part 2

[@jbj27406]

Yeah, that was my question too. For instance, does Hoover Dam rely on the pressure of the lake pushing on it to maintain its integrity?

[@daftbence]

Very much a lackluster video that managed to miss answering the question... :(

[@johnc4224]

@@jbj27406 no since concrete will always keep its strength when well maintained if it was made of loose stone it would be an issue you might have to worry about it

[@Brandon-uy1uv]

No difference between wet and dry concrete, or else my house would of fallen in the summer.

[@rherman9085]

Another great video Grady. I keep hearing about how dry this spell (drought ) has become yet the comparisons seem to reach well passed hundreds of years. The Dustbowl during the 19030's doesn't ever get mentioned in these conversations. Why is that?

[@Br3ttM]

It's a different part of the country, so their climate doesn't follow the same patterns, and the dust bowl had a lot to do with land usage, and the removal of the native grasses that held the soil in place to put in farms of annual crops without extensive root systems.

[@xakepbamfsol]

I'm not sure if this pun was intended, but I appreciate the irony of talking about droughts and water shortages while also showing footage of Camelback Mountain in Arizona at 9:23.

[@phillipdarling2642]

How about a video on the types of testing or examination construction projects require and why?

[@dharanidharsoma]

Great Video Grady, DO hydraulic Engineers use HEC-RAS Software in order to analyze and design the Reservior based on the 100 year flood design or do they design based flood frequency curve.

[@alfonsomunoz4424]

You seem a lot more calm about the situation than I think people in Southern California and Arizona should be.

[@tritamtran7264]

ok

[@cbmazo9229]

That’s what I’m saying “It’s not necessarily a bad thing!” Okay mf, but what if the constant trend that’s ya know, been continuing for the past 40 years, but now at really *critical* levels, continues on for another 10 years? What’re you gonna say then? “Oh, it’s not a bad thing!”

[@alfonsomunoz4424]

@@cbmazo9229 I love it!

[@jimmym3352]

nah, if the states would cut water usage by 1/3 like the Federal government is trying get the states to do, we'll be fine. Problem is the states won't cut water, California feels like they can do what they want because of their political power, and because they won't cut, no one else will either. But it will happen eventually. Farming may be out, but the people aren't going to run out of water. Just expect food prices in the winter to go up by well over 100% since we can't get winter vegetables from California and Arizona.

[@gordonspond8223]

Thank you for covering this in an objective and non-emotional manner. We need more level-headed people like you.

[@fishingdudeable]

I just watched both of your Video's about Oroville Dam I live 15 min away up hill so was never in any danger but we heard the biggest problem was poor management the summer prior to the spill way they did not do proper up keep > Who knows I know engineers that worked on the dam when it was built it has some good stories about gold attached to it. As always there is going to be people covering their butts and saving their jobs First this area was hit with this spillway failer then On November 8 2018 The town I do live in was hit by the most deadly wildfire in history The Camp Fire that was caused by a power line arcing sparks falling on to the dry grass and the rest is history I think Our Butte county Sheriff Kory L Honee did a amazing job getting us threw both of those disasters . You videos are really good Thank you for doing them

[@Lex4122]

These are so good, thank you very much for making them!

[@mitchelschaller9214]

Heck yeah! Shasta Dam for the win again! I'm a Redding native who is currently working in Loveland CO on the second "asphalt core" Dam in the US. Would love to see you describe the different cores of dams and why one is more likely to be chosen than the other. We have an outfit from Switzerland who is building the actual core, apparently they are more common in Europe?

[@hauntedshadowslegacy2826]

Ay, I almost drowned in Lake Shasta some years back. How's the hike to the water now? Fire ants still all over?

[@mitchelschaller9214]

@@hauntedshadowslegacy2826 hike is still a good 100 ft depending where you are at. Haven't really had an issue with ants the whole time I have lived there though

[@zephyer-gp1ju]

Been a number of years but, last time I flew over Phoenix there were open irrigation canals, manmade lakes for decoration at subdivisions, and more golf courses than you can shake a stick at. Kind of the same with California. Time to put water in pipes, more rough area for golf courses. Maybe fewer swimming pools too.

[@brendakrieger7000]

A very scary situation🙀 I appreciate you talking about this topic💜

[@nenmaster5218]

Some More News and Second Thought are 2 KZbinrs famous for being Voices for the Worker-Class. Their videos about Work, Unions, and Capitalism, are amazing.

[@jeremyowen1]

We're experiencing incredibly low water levels on the Thames River in Ontario, Canada as well. I went fishing there this morning and the river narrowed from 20-30+ ft to a 4-5 foot wide rapid in some places. Great fishing though, I'll be honest. Seems like everywhere needs some constant steady rain to replenish. I haven't seen green grass in at least a week.

[@wolfecanada6726]

Sad situation to be in when Canada has over half of the potable fresh water on earth

[@BasementEngineer]

I live in Cambridge ON and the Grand River is very low, too. It's definitely a dry summer here. Whether it is a record dry remains to be seen.

[@jeremyowen1]

@@BasementEngineer I don't remember ever seeing the Thames quite as low as it is right now, but I also can't say for sure. It's not unusual for it to be down either though, especially this time of year. But it's sort of scary how it's almost completely cut off in a few places. Just a 2ft wide channel of moving water.

[@rodchallis8031]

@@jeremyowen1 Yeah, it's low, but it came back up a little. I keep an eye on the river on my walks, crossing the bridge by the Hunt weir behind Labatt's. On Saturday it was a good 2 to 3 feet below the top, but due to the rain we got in the wee hours of Monday morning, it came back up and is overtopping the weir. I'm sure it's been lower than this in the past. It's been dry so far this summer, but the drought of '69 was much worse than this, and there was that drought in the 80's. Drought being a relative term-- a "drought" by South Western Ontario standards. More telling, perhaps, is a small creek that runs through Westminster Ponds. When I was a kid, before beavers moved back in at Thompson Pond, that creek (Dayus creek) would always dry up. Since the beavers moved back in, I notice the creek always flows year round. Last weekend I checked it out, and the flow had pretty much stopped, though much of it still held standing water. there's usually seepage at the beaver dam, but I notice that had stopped. Never seen that before-- though, there were no beaver there in '69. Water levels behind the beaver dam are just down a smidge from normal.

[@joshpodolsky7740]

Here in the parkland region of MB we've had drought for the past 4 years now. This spring we had a 100 year flood but ever since the beginning of June I'd say we are back to drought. All those years of dry soil just sucked up all the flood water from this spring. I remember cutting THICK grass at my parents place when I was a kid. The past 3-4 years it's just yellow brown grass, some places it's just dirt.

[@skenzyme81]

It's not a reservoir going dry. It's natural canyon restoration! 😜

[@jandecreates8251]

lol No drought, Just water removal. : )

[@skenzyme81]

@@jandecreates8251 Now you're getting it! 😂

[@prodrom]

200iq

[@thamizhansurya8519]

Earth feeling thirsty so it's drinking the water.

[@samsonsoturian6013]

You should hear about the "rewilding" in England. No, they ain't abandoning it, they just turned it into a public park with a dark ages vibe.

[@Bren553Gaming]

You should do a video on the infrastructure Las Vegas has in place to deal with cleaning tons and tons of water to be put back into lake mead. would be an interesting video for those who do not know about Vegas' water conservation efforts.

[@d0n1mega]

You answered my question!! Thank you!!

[@ai_is_a_great_place]

Amazing video! But I can't help but feel this was more of a discussion on the repercussions of a reservoir going dry, rather than the actual effects that has on the physical reservoir structure. That was what I was thinking this may be a deep dive on based on the video title. But again, it was still a great video!

[@1smallball]

Exactly what I was thinking. The title doesn't match the video.

[@timinator8652]

The reservoir structure will be fine, it was built dry and then filled up, so it will continue to stand if drained again. Many things were not touched on in this video, it was interesting but would need to be much longer to dive into details. And the effects are going to be different depending on the purpose and location of the dam.

[@madhumadhu-pb2yz]

Nice video

[@Visionery1]

Many older dams are largely filled with silt, reducing their capacity even further, you should do a video on that. 50% full may in reality only be 20%, or less.

[@VecheslavNovikov]

There's one plus, one of those going dry would allow for cheap earthworks to clear the silt.

[@Visionery1]

@@VecheslavNovikov what to do with it, there are millions of tons. Here you can see just how much: kzbin.info/www/bejne/an3bfnujrJiNY7c

[@VecheslavNovikov]

@@Visionery1 Isn't it a good sort of earth to cover depleted farmland? You can cover barren land with it to make new farmland. If you can separate out the clay, that has uses in building and architecture.

[@Visionery1]

@@VecheslavNovikov I think you may be right, it's fertile soil washed down from upstream.

[@MB-pr1eo]

Awesome report. Thank you

[@k1ngr3y]

In Lee county FL, the C43 reservoir is being built to control the salinity of the caloosahatchee estuary.

[@mgkleym]

As a Oklahoma I am outraged Grady would tell the world about our dry beaver.

[@robertshelton3796]

Grady when you're using stock footage it'd be great if we had an idea of where it was. The dam at 3:51 has a unique spillway and I'd love to learn more about it

[@Mitglied99]

4:02 is Schwarzenbach-Talsperre in Germany... in case someone ask

[@Sofie424]

5:07?

[@phillipdarling2642]

How about a video on methods or inert gas shielding/purging during welding pipe/tube? Also the risk of welding in a moisture rich environment.

[@Nubbe999]

The problem with US water usage is that farmers grow crops that need a lot of water in places without water and in places with a lot of water crops that don't need much water are grown. When a well o reservoir goes dry the earth gets dry and hard and it will not hold as much water. US cities do not save water that comes from rain but it is just flushed away as fast as possible. US environmental laws are not as strict so the risk of getting contaminated water or over use is bigger than in for example Europe.

[@winstonelston5743]

10:40 I seem to remember that there actually were springs in the bed of Optima Lake, or perhaps it was another case study from my college days. Rather than fill the reservoir, the water went to recharge the aquifer. You can't store water in a sieve.

[@adrianjohnson7920]

Yes, it was Optima reservoir; the thing stands there empty. They didn't do their hydrology/geology homework before building that dam in the Oklahoma panhandle.