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The Los Angeles Aqueduct Is Wild

practical.engineering

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Re: The Los Angeles Aqueduct Is Wild

#41

Post by simtel20 »

devilbunny wrote: post #21
gorfian_robot wrote: post #11

Being 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.

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.

Where did you get that idea about NYC water being untreated? NYC treats its water. Chlorine is added if and when needed. Testing stations exist to evaluate water quality all around the boroughs, etc.

You can't have a city of millions of people and have the water be potable from the tap without testing and treatment

Re: The Los Angeles Aqueduct Is Wild

#42

Post by detourdog »

rtkwe wrote: post #14
JumpCrisscross wrote: post #6

Earlier quoted context omitted.

> the up-front costs of massive desalination Desalination is dominated by operating costs.

Correct 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.

A scaled down perspective is….

The most efficient commercial desalinator for boats is 32 Watts a gallon.

Re: The Los Angeles Aqueduct Is Wild

#43

Post by fhdkweig »

larkost wrote: post #37
gorfian_robot wrote: post #11

Being 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.

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?

Re: The Los Angeles Aqueduct Is Wild

#44

Post by whalesalad »

mjamesaustin wrote: post #30

Growing 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.

My 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.

Re: The Los Angeles Aqueduct Is Wild

#45

Post by jedberg »

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 (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.

Re: The Los Angeles Aqueduct Is Wild

#46

Post by mikestew »

devilbunny wrote: post #21
gorfian_robot wrote: post #11

Being 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.

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."

Re: The Los Angeles Aqueduct Is Wild

#47

Post by jonathonlui »

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...

Re: The Los Angeles Aqueduct Is Wild

#48

Post by fhdkweig »

detourdog wrote: post #42
rtkwe wrote: post #14

Earlier quoted context omitted.

Correct 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.

A scaled down perspective is…. The most efficient commercial desalinator for boats is 32 Watts a gallon.

Do you mean 32 Watt-hours / gallon?

Re: The Los Angeles Aqueduct Is Wild

#49

Post by weaksauce »

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…

to put this to numbers... the exports are just about 0.5% of california's GDP. so yeah pretty much a rounding error.

Re: The Los Angeles Aqueduct Is Wild

#50

Post by kibwen »

rabid_0wl wrote: post #29
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.

Those projects would literally be impossible today with the environmental regulations in place, especially in California.

If you watch the OP, you'll see that the construction of this aqueduct caused billions of dollars worth of environmental devastation. Rail all you want against regulations, but when an argument boils down to "I wish we didn't have to internalize all these costs and could just push them off on someone else", I'm not especially sympathetic.
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