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The Los Angeles Aqueduct Is Wild

practical.engineering

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Re: The Los Angeles Aqueduct Is Wild

#51

Post by jmalicki »

mikestew wrote: post #46
devilbunny wrote: post #21

Earlier quoted context omitted.

I 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.

I know NYC doesn't treat their water at all… EDIT: I'm a dork an grabbed the wrong URL. Changed URL to a PDF for lack of better. A major metro doesn’t treat its tap water? Where on earth did you get that crazy idea? https://www.nyc.gov/assets/dep/downloads/pdf/water/drinking-... I'll save some digging: "Even without filtration, the water is carefully treated to reduce the risk of harmful microorganisms."

He was talking about the drinking water that comes from the faucet, not the sewage.

The untreated NYC water has tiny crustaceans in it, which make it not Kosher, which is why thee bagels from a Jewish deli in NYC are so good. Go figure.

https://newsfeed.time.com/2010/08/31/drink-up-nyc-meet-the-t...

Re: The Los Angeles Aqueduct Is Wild

#52

Post by SCUSKU »

hamdingers wrote: post #38
z3ugma wrote: post #17

"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 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

There 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 internationa…

Anecdotally, 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!"

Re: The Los Angeles Aqueduct Is Wild

#53

Post by kibwen »

bombcar wrote: post #5

I wonder at what point the up-front costs of massive desalination would overcome the (often hidden and externalized) costs of projects like this.

As long as we don't try to hide and externalize the cost of all the hyper-saline brine management that comes with desalination.

Re: The Los Angeles Aqueduct Is Wild

#54

Post by zardo »

BryantD wrote: post #18
strongpigeon wrote: post #16

Sometimes 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.

I 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. :(

Can'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.

Re: The Los Angeles Aqueduct Is Wild

#55

Post by johngunderman »

mikestew wrote: post #46
devilbunny wrote: post #21

Earlier quoted context omitted.

I 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.

I know NYC doesn't treat their water at all… EDIT: I'm a dork an grabbed the wrong URL. Changed URL to a PDF for lack of better. A major metro doesn’t treat its tap water? Where on earth did you get that crazy idea? https://www.nyc.gov/assets/dep/downloads/pdf/water/drinking-... I'll save some digging: "Even without filtration, the water is carefully treated to reduce the risk of harmful microorganisms."

You linked to wastewater treatment, not drinking water. Wastewater is definitely treated in NYC.

Tap water is treated (UV and chloride disinfecting), but is largely not filtered: https://en.wikipedia.org/wiki/New_York_City_water_supply_sys...

Re: The Los Angeles Aqueduct Is Wild

#56

Post by rimunroe »

jonathonlui wrote: post #47
rimunroe wrote: post #13

I 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.

There'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-cove...

Thanks! 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!

Re: The Los Angeles Aqueduct Is Wild

#57

Post by kenhwang »

jedberg wrote: post #45

The 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 (b…

Owens 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.

Re: The Los Angeles Aqueduct Is Wild

#59

Post by mikestew »

jmalicki wrote: post #51
mikestew wrote: post #46

Earlier quoted context omitted.

I know NYC doesn't treat their water at all… EDIT: I'm a dork an grabbed the wrong URL. Changed URL to a PDF for lack of better. A major metro doesn’t treat its tap water? Where on earth did you get that crazy idea? https://www.nyc.gov/assets/dep/downloads/pdf/water/drinking-... I'll save some digging: "Even without filtration, the water is carefully treated to reduce the risk of harmful microorganisms."

He was talking about the drinking water that comes from the faucet, not the sewage. The untreated NYC water has tiny crustaceans in it, which make it not Kosher, which is why thee bagels from a Jewish deli in NYC are so good. Go figure. https://newsfeed.time.com/2010/08/31/drink-up-nyc-meet-the-t...

Thanks for the correction, I should have looked harder at that page before posting. I've since corrected.

Re: The Los Angeles Aqueduct Is Wild

#60

Post by larkost »

fhdkweig wrote: post #43
larkost wrote: post #37

Earlier quoted context omitted.

I wonder if this was in an apartment building. We owned a condo in a 5 story (4+1) apartment building and because it was taller than the San Jose water system was built for, our building needed (electric) pumps to provide water pressure to the building (there were tanks on the roof). If we lost power, then we lost water. Now that we have moved to a 2 floor detached home (also in San Jose) we do not have that issue, a…

Do you lose water in the whole building, or just those apartments above the water-line?

We happened to live on the top floor, so I don't have personal experience for the lower floors, but the communication on the (non official) group chat for the building always hinted that any water outages (we had a few non-power issues with the pumps as well) applied to to the whole building. But thinking back that could be an unfounded assumption.
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