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The Los Angeles Aqueduct Is Wild
- anjel 6mo agoNice picture but I've never seen the water anywhere near blue like that.
- Supermancho 6mo agoThat's a youtube thumbnail. I believe it's been altered, which also explains the strange brown substance that looks out of place. Most of the video content has the correct coloring, from my experience observing the aqueduct.
- w4der 6mo agoI think it's edited to look like water he uses in his garage demos.
- 3happyrobots 6mo agoReally enjoyed watching that. Good luck with water LA.
- bombcar 6mo agoI wonder at what point the up-front costs of massive desalination would overcome the (often hidden and externalized) costs of projects like this.
- JumpCrisscross 6mo ago> the up-front costs of massive desalination Desalination is dominated by operating costs.
- rtkwe 6mo agoCorrect it's massively energy intensive to filter the salt out the newest best ideas still use ~2 KWh/m3 of water and that's a lab system in perdue that batches the process instead of having it run continuously which is why current RO desalination systems require so much energy.
- smm11 6mo agoCalifornia pays other states to take its excess solar energy. Power for a project like this isn't the issue, actually building the system is the issue.
- JumpCrisscross 6mo ago> California pays other states to take its excess solar energy Intermittently. Essential services like water (with expensive fixed costs) aren’t a good fit for absorbing variable supply. > Power for a project like this isn't the issue California has the country’s most expensive power [1] in part due to policymakers constantly assuming it’s free. [1] https://www.electricchoice.com/electricity-prices-by-state/ https://www.electricchoice.com/electricity-prices-by-state/
- rtkwe 6mo agoThey wouldn't if you switched just Urban water use from natural sources to desalination. To do that you need to replace the ~5 million acre feet of water, ~6,167,400,000 m3, that goes into the Urban bucket which is all of the water used to keep people alive, clean, and all industrial uses of water. [0] That comes to ~ 12BkWh of energy needed to scale up batched reverse osmosis to take over just the life and job required water needs which is about 25% of the total solar power generated in all of 2025 via grid-scale solar farms. CA does export some during the day due to excess solar but is still a net importer of power. [0] p2 of https://cwc.ca.gov/-/media/CWC-Website/Files/Documents/2019/06_June/June2019_Item_12_Attach_2_PPICFactSheets.pdf https://cwc.ca.gov/-/media/CWC-Website/Files/Documents/2019/...
- bombcar 6mo agoThose are the numbers I was looking for - that means that (ignoring build-out costs) total desalination for CA would be on the order of 10% of the 3 gorges dam yearly output (max).
- rtkwe 6mo agoUsing a system that's currently in a lab scale only and ignoring other energy costs like moving the water to the plant, mixing the briny output back down to acceptable levels, and then pressurizing the system to replace the gravity fed design it currently uses. For a rough estimate for replacing agricultural uses too ~6x that urban figure at least then weep at the amount of pumps you'd need to bring that water up and inland to the farm lands from the coast. At least for replacing urban use most of the population lives on/near the coast where the water would be produced.
- kjkjadksj 6mo agoI don’t think the brine pollutant issue has been meaningfully solved. You are also now pumping water inland uphill the whole way.
- SoftTalker 6mo agoFor usage where the water mostly returns as sewage, is treated and then returned to the ocean, you can just dilute the brine with the treated discharge and then it returns at basically the original salinity.
- kenhwang 6mo agoIt is common now for treated discharge to be sent to a discharge lake/leach wetlands so it can be used to replenish groundwater supplies.
- kibwen 6mo agoAs long as we don't try to hide and externalize the cost of all the hyper-saline brine management that comes with desalination.
- bombcar 6mo agoWe can store it in the remains of Owens Lake ;)
- deleted 6mo ago[deleted]
- hparadiz 6mo agoThe California aquaduct system is an engineering marvel.
- KerrAvon 6mo agoIf anyone wants a deep dive on this subject: https://en.wikipedia.org/wiki/Cadillac_Desert https://en.wikipedia.org/wiki/Cadillac_Desert
- actionfromafar 6mo agoOr another kind of take: https://www.imdb.com/title/tt0071315/?ref_=nv_sr_srsg_0_tt_8_nm_0_in_0_q_chinato https://www.imdb.com/title/tt0071315/?ref_=nv_sr_srsg_0_tt_8... (Chinatown)
- willturman 6mo agoOr another kind of take: Land of Little Rain by Mary Hunter Austin https://www.goodreads.com/book/show/91707.The_Land_of_Little_Rain https://www.goodreads.com/book/show/91707.The_Land_of_Little...
- jackconsidine 6mo agoCame here to post this. Dam good book on the shifty maneuvering that resulted in the Owens Valley Diversion and ultimately the population center that is LA.
- hvb2 6mo agoThat bit of history can't be left out. The engineering is super cool though.
- gorfian_robot 6mo agoBeing from LA, I am used to a water system that works without needing power. I think most of CA is like that. It was a surprise to lose the water back east when the power went out during a storm.
- duomo 6mo agoThe LA water system is dependent on power as a whole. There’s many pumping stations along the various aqueducts.
- labcomputer 6mo agoSome of the aqueducts that deliver some of the water to LA do rely on pumping. But, the Los Angeles Aqueduct, which is the subject of this post, does not. The LA Aqueduct is entirely gravity driven, and under normal circumstances it is sufficient to supply LA's water needs. Another nitpick is that California's various aqueducts are net producers of electricity (i.e., after accounting for pumping), so, while some of them do rely on electricity, they do not require an external source of power to operate.
- tjwebbnorfolk 6mo agoWe do not lose water on the east coast when the power goes out
- Spooky23 6mo agoIt depends where you are. Most cities in the Northeast you are correct. But coastal areas, big swaths of New Jersey and Long Island IIRC are definitely dependent on power. Towns with water towers usually pump it from the ground. Alot of suburbs that can't or won't hook into city supplies will sometimes need more active measures to filter their water as well. Sanitary sewers are heavily dependent on power.
- devilbunny 6mo agoI know NYC doesn't treat their water at all, but LA doesn't either? My city runs on surface water, so we have treatment and then pump to storage tanks. You would have to be out for quite a while to run the city out of water, though - the tanks are large.
- rimunroe 6mo agoI was surprised to find out it was largely uncovered, though I guess it probably makes it much cheaper to construct. I usually think of aqueducts as pipes or tunnels, like Persian qanāts. I wonder how much water is lost due to evaporation.
- jonathonlui 6mo agoThere's some testing to see how covering open irrigation canals with solar panels which would reduce evaporation and generate power > Their analysis found that putting solar panels over the 4,000 miles of California’s open canals could save up to 63 billion gallons of water annually https://www.universityofcalifornia.edu/news/solar-panel-covered-canals-have-their-day-sun-california https://www.universityofcalifornia.edu/news/solar-panel-cove...
- rimunroe 6mo agoThanks! I forgot that article, but now I remember that I read or skimmed it when it made the rounds last year. It's actually where I first learned that the aqueducts were uncovered!
- masklinn 6mo ago> could save up to 63 billion gallons of water annually To put it into perspective, 63 billion gallons is 193340 acre-feet, which is 0.5% of california's water use (a bit under 40 millions acre-feet). That's a tenth the water consumption of lawns, which is 1/15th the water consumption of agriculture.
- kyledrake 6mo agoI was in Owens River Gorge last week, it's a very interesting place. It has some of the tallest single pitch rock climbing in the world, sometimes requiring 80M ropes: https://www.mountainproject.com/area/105843226/owens-river-gorge https://www.mountainproject.com/area/105843226/owens-river-g...
- Fricken 6mo agoThe Owens river gorge has the highest concentration of sport climbs anywhere in North America, but there's not much variation, they're mostly edge ladders on weirdly slippery rock. Not far away are the world's most photogenic boulders, the Buttermilks, and when I visited (from Canada) I was surprised to find that the boulders are on LA municipal property and the pipe that takes Owen's River's water over the Sierras is nearby.
- strongpigeon 6mo agoSometimes it feels like the US has lost its appetite for grand structural projects like that. Maybe it’s just that I’m unaware of them and that impression is the result of survival bias, but given how impossibly hard it is to just build anything where I live (Seattle), I’m not so sure.
- BryantD 6mo agoI don't think you're wrong. Every time someone says we can't do high speed rail it makes me very sad. And as far as Seattle goes... my commute is substantially affected by the I-5 closures. It's somewhat shocking to me that we allow infrastructure to decay as much as we do. I'd be happy about the light rail expansion if they weren't talking about delaying the Ballard line indefinitely. :(
- amanaplanacanal 6mo agoEvidently tax cuts for the wealthy are more important than infrastructure.
- zardo 6mo agoCan't do highspeed rail because it's too impractical and expensive, while we're spending a west coast highspeed rail network worth of money on the least popular war in US history.
- coryrc 6mo agoCalifornia is spending the money and what they're building is useless (oh big passenger demand from Merced to Bakersfield, fuck right off with that) and costs 10x what China, France, Japan, etc pay.
- mlrtime 6mo agoThere are no environmental impact studies on wildlife when you drop a bomb.
- coryrc 6mo ago
- z3ugma 6mo ago"Well There's Your Problem" on the collapse of the St Francis Dam, mentioned in Grady's video https://www.youtube.com/watch?v=hxLgM1vnuUA https://www.youtube.com/watch?v=hxLgM1vnuUA Also I love when they refer to it as the "_First_ California Water Wars" in a grim realization of the future of water scarcity in the West
- hamdingers 6mo agoThere is no water scarcity in California, only misallocation. The vast majority of our water is heavily subsidized and used for agriculture, and a substantial amount of those crops are grown for export, yet agricultural exports makes up an insignificant part of California's economy. We could end all California water scarcity talk today, with no impact to food availability for Americans, by curtailing the international export of just two California crops: almonds and alfalfa.
- weaksauce 6mo agoto put this to numbers... the exports are just about 0.5% of california's GDP. so yeah pretty much a rounding error.
- chrisrogers 6mo ago0.5% is a far cry from a rounding error..
- panzagl 6mo ago0.5% is like the literal definition of a rounding error.
- SCUSKU 6mo agoAnecdotally, my friend's grandma was an almond farmer. As they drove past a river in the Central Valley, she exclaimed "Why is there water in that river?! Those could be watering my almond trees!"
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- babblingfish 6mo agoI really dig the editorial viewpoint of this article. New journalism style meets fun facts about engineering.
- mjamesaustin 6mo agoGrowing up in LA, I was fascinated as a kid watching the water flow down this aqueduct. Anytime we drove by it on the way to Magic Mountain, I'd hope that it would be a water-on day.
- whalesalad 6mo agoMy dad lived in Palmdale, my mom lived in Glendale. I made that trip a LOT. It's cool when it is all lit up with the colorful lighting.
- jedberg 6mo agoThe norcal/socal divide caused by the river is funny to me. I grew up in LA, then moved to the Bay Area for college. In LA we never really talked about where our water comes from. But we were always 'in a drought' and always taught to conserve water. My wife grew up in the Bay Area, and was told the same. But her family is from Sacramento. Up until about 15 years ago, everyone in Sacramento paid the same for water (based on square footage of your home). There were no water meters. So they didn't conserve. They ran the sprinklers in 100 degree heat for hours, they washed sidewalks with water instead sweeping, and all the other things. But when the meters came, her Uncle blamed SoCal for "stealing his water". He complained every month when the bill came about how he has to pay more now because of SoCal.
- kenhwang 6mo agoOwens valley, where LA "steals" water from, is on the eastern side of the Sierras. NorCal, including Sacramento, is on the western side of the Sierras. So unless they planned on pumping the water over/under the mountain range that surrounds it in every direction except for towards LA, that water was never available for any NorCal city to use.
- dgaultiere 6mo agoLA also gets water from the state water project which does come from northern california: https://upload.wikimedia.org/wikipedia/commons/thumb/e/e5/California_State_Water_Project.png/500px-California_State_Water_Project.png https://upload.wikimedia.org/wikipedia/commons/thumb/e/e5/Ca...
- jlhawn 6mo agothey are saying that LA takes water from sources which would otherwise drain into the sacramento and san joaquin river delta. The video from this post mentions the California State Water Project which takes water from the Feather River (Oroville Dam) and distributes it along the Western edge of the central valley South to Bakersfield where it is then pumped over the mountains both towards Los Angeles and further East to San Bernardino and Riverside. It provides way more water to SoCal than the two Los Angeles-specific aqueducts from the Owens Valley on the Eastern side of the Sierras.
- wolandomny 6mo agoI remember hearing years ago that this aqueduct was going to be shut down and then it just... never was? Does anyone else recall that?
- TheGrassyKnoll 6mo agoSome say the LA aqueduct saved Owens Valley from development. (I’m sure the old timers out there would have a different opinion)
- bell-cot 6mo ago> (I'm sure the old timers ... Something along the lines of "we fought tooth and nail to save LA from development"?
- TipsForCanoes 6mo agoFor anyone interested in a deep dive, I recommend the book Vision or villainy: origins of the Owens Valley-Los Angeles water controversy.
- PeterStuer 6mo agoWhy is that picture an extreme recolor of the original? https://images.nebula.tv/5ba7e541-f57c-44cc-a91d-6a89bad158dc https://images.nebula.tv/5ba7e541-f57c-44cc-a91d-6a89bad158d...
- observationist 6mo agoTo make people click.
- fritzo 6mo agoThank you, I was so confused by the obvious clickbait! I love Grady's videos, but yikes.
- w4der 6mo agoI said this in another comment, but I feel it's edited to look like water he uses in his garage demos with that blue glitter.
- retrac 6mo agoThere's a poem carved into the stonework of Washington Union Station, part of the art installation The Progress of Railroading from c. 1909: the old mechanic arts / controlling new forces / build new highways / for goods and men / override the ocean / and make the very ether / carry human thought the desert shall rejoice / and blossom as the rose
- willturman 6mo ago> the desert shall rejoice / and blossom as the rose Or, rewritten for the Los Angeles Aqueduct: the desert shall wither / and blossom in a plume of dust [1] [1] https://www.latimes.com/environment/story/2025-06-19/owens-valley-dust https://www.latimes.com/environment/story/2025-06-19/owens-v...
- hnburnsy 6mo agoMy favorite part of this video is where they divert and dry up one lake, and then build two reservoirs further downstream.
- notepad0x90 6mo agoLooking at what Tehran is facing (not related to the war, water shortage), I'm wondering why california isn't investing in more desalination for SoCal, especially for LA. I see some here: https://lynceans.org/all-posts/status-of-desalination-plants-in-california-2/ https://lynceans.org/all-posts/status-of-desalination-plants... But there are only a few in SoCal and they're for smaller communities like carlsbad or santa barbara. So it is there and it is working for some, why not more? naturally i assume it's because everything costs more at the coast.
- peterbecich 6mo agoThere are environmental and financial concerns https://calmatters.org/environment/2022/05/california-desalination-plant-coastal-commission/ https://calmatters.org/environment/2022/05/california-desali... I don't understand the financial concern at all. How could increasing the water supply increase the price? It only makes sense to me if the price is artificially low right now. Environmental damage by a desalinization plant couldn't possibly be worse than overdrawing the acquifer -- the defacto solution.
- daedrdev 6mo agoBuilding an industrial facility in california is much more difficult and expensive due to numerous regulations.
- harrall 6mo agoAs part of the contract for construction, the county or city must buy a certain amount of water every year. Because desalination is not economically feasible, the water is more expensive and this extra subsidy raises the cost of the water bill. This is how it works for the facility in San Diego County. Building a desalination facility is economically hard to justify because the break-even point seems far away. It also assumes the state won’t eventually create a state-wide solution, which would benefit from a state-level economy of scale that a city/county effort might not.
- deleted 6mo ago[deleted]
- scoofy 6mo agoJust a quick plug for Cadillac Desert. People don't realize how fragile the urban areas of Coastal California are. We should. https://en.wikipedia.org/wiki/Cadillac_Desert https://en.wikipedia.org/wiki/Cadillac_Desert
- rkagerer 6mo agoAm curious, how have the shade balls been working out in terms of maintenance, coating wear, leeched microplastics, containment (so they don't wind up in oceans), etc? In retrospect, did it make sense compared to the $250M or so uplift it would have taken to build a conventional roof?
- lazide 6mo agoNo way they could feasibly have built a roof over that reservoir.
- boisterousness 6mo ago2020 update: https://wateroperator.org/blog/featured-video-why-are-96000000-black-balls-on-this-reservoir https://wateroperator.org/blog/featured-video-why-are-960000...
- phyzome 6mo agoPretty upsetting history along with the interesting engineering.
- rootusrootus 6mo agoIs it really considered the Cascades all the way down near LA? I thought the mountains down there were the Sierra Nevada? Did Grady just get that detail wrong, or am I wrong in thinking that the Cascades stops in Northern California?
- pwarner 6mo agoA cascade is a steep, small waterfall or a series of such falls, often describing anything falling in stages.
- tug2024 6mo ago[dead]
- subpixel 6mo agoReminds me of when I was talking to friends about the film Chinatown and I referred to it as a movie about the California water war and someone else said “dude, that’s not what that film is about”. We were both correct.
- gz5 6mo agoNYC aqueduct from the Catskills is wild too, especially if you like the effect on NYC pizza and bagels. Great articles have been written on the engineering but I like this one from 1909 showing the perspective of the time: https://www.catskillarchive.com/rrextra/dnaque.Html https://www.catskillarchive.com/rrextra/dnaque.Html
- lproven 6mo agoQuite interesting. This is also why every video needs a transcript: that took me 6min to read, about 1/4 of the video's running time.
- bagacrap 6mo agoThe graphical aids in practical engineering videos are quite well done, especially when he creates scale models in the garage. You are missing out if you only read it, if you can afford to spend the time watching.
- zahlman 6mo agoNothing prevents inserting video clips — or, for that matter, interactive demos or other media — into the flow of a blog post. Youtube incentivizes its "creators" to optimize for view time, so even the most respected channels can be quite redundant in their presentation. And even when it's well edited and "organized", it doesn't necessarily prioritize what would be most useful.
- CommenterPerson 6mo agoI love Practical Engineering. Grady Hillhouse's enthusiasm for engineering shows through brilliantly. Being a graduate engineer, I've learned a lot from his videos and transcriptions. Well worth browsing practical.engineering. PS: and it is NOT about software engineering LOL!
- laaqua 6mo agoDoes anyone know why there's been a bit of a surge of videos/articles about this? Or am I just getting Baader-Meinhof ed? https://www.youtube.com/watch?v=GeYvNkaLAqA https://www.youtube.com/watch?v=GeYvNkaLAqA https://www.youtube.com/watch?v=aGNE-xVk8OE https://www.youtube.com/watch?v=aGNE-xVk8OE
- dhalucario 6mo agoInsane waterslide