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The Los Angeles Aqueduct Is Wild

practical.engineering

21–30 of 216 posts

Re: The Los Angeles Aqueduct Is Wild

#21

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.

Re: The Los Angeles Aqueduct Is Wild

#22
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.

I don’t think the brine pollutant issue has been meaningfully solved. You are also now pumping water inland uphill the whole way.

For 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.

Re: The Los Angeles Aqueduct Is Wild

#25
post #18

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. :(

Evidently tax cuts for the wealthy are more important than infrastructure.

Re: The Los Angeles Aqueduct Is Wild

#26

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.

You mean, like NYC Water Tunnel #3? https://en.wikipedia.org/wiki/New_York_City_Water_Tunnel_No....

Re: The Los Angeles Aqueduct Is Wild

#27

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.

LA definitely treats the water. Both the surface water before consumption (I'd be surprised if any city doesn't do this) and the wastewater, for reclamation for nonportable use like irrigation, and for recycling back into the general clean water supply.

The aqueduct water is specifically purified by the Los Angeles Aqueduct Filtration Plant. That plant is gravity fed, but it doesn't operate without power.

LA just has the advantage of having mountains in the city, so it's cheaper building more elevated water storage so the capacity lasts longer during power interruptions (which are also not as common or extended as they are in the east). They will still eventually run out if they're not replenished by powered pumps.

Re: The Los Angeles Aqueduct Is Wild

#28

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.

Seattle just got done building light rail tracks over a floating bridge.

It is an insane engineering achievement. A train literally running on tracks on a road that is floating on water!

Re: The Los Angeles Aqueduct Is Wild

#29

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.
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