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A vision for the alleviation of water scarcity in the US Southwest

caseyhandmer.wordpress.com

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Re: A vision for the alleviation of water scarcity in the US Southwest

#51

Post by MostlyStable »

I know he inputs some numbers, but I am just supremely skeptical of them. If solar + batteries + RO plants could produce water at a price that made agriculture economically viable, then I just don't see how it wouldn't already be happening. Or at the very least be being proposed more broadly than some random guys blog.

If I understand correctly, it is his plan for extracting value from the brine which represents the biggest unknown/the most need for development, while also being the thing that makes it all make sense. I've never heard of any of the existing worlds desal plants doing this, so either it must be harder than he supposes or else he must think that every single person in charge of a desal plant the world over is an idiot.

Don't get me wrong, I realize that sometimes people miss obvious things. And sometimes, there really is a $100 bill on the ground, despite what the apocryphal economist would have you believe.

But in this case, areas like that are what I need to be convinced of. While it's maybe true, you don't just get to assert it.

As they say "What can be asserted without evidence can be dismissed without evidence".

Re: A vision for the alleviation of water scarcity in the US Southwest

#52

Post by jakderrida »

alexb_ wrote: post #49

Just charge people for the natural resources of the country via taxes. Resource and land taxes solve basically every single problem in the current American economy yet people do not want to even think about doing it.

> yet people do not want to even think about doing it.

probably because placing a price on some things seems too transactional. Not saying you're wrong, though. Just saying that's why. The alternative is allowing more rapacious disregard for the aggregate negative effects on everyone as a whole.

Re: A vision for the alleviation of water scarcity in the US Southwest

#53

Post by datadrivenangel »

floatrock wrote: post #34
bryanlarsen wrote: post #31

Earlier quoted context omitted.

AFAICT, restoring the Salton Sea and capturing the land appreciation is the mechanism for funding the project, not the goal. The goal is to restore the Colorado river.

And what pays for it again in a decade when the corroded water pipelines start to need replacement? Or 30 years when the solar reaches end of life? I assume original developers will have cashed out by then, someone else is left holding the bag, and the Salton Sea collapse story plays out a second time because it's just too expensive to maintain. That, or it's an exclusive enclave to the LA ultra-wealthy who don't min…

We must maintain our life support machines.

Or move to places that don't need them.

Re: A vision for the alleviation of water scarcity in the US Southwest

#54

Post by hcknwscommenter »

ketchupdebugger wrote: post #11
hnmullany wrote: post #3

Apart from whether the economics make sense brine disposal from desalinization is a big issue. Waste with high salt concentrations can wipe out marine life - it would be nice if this piece took the issue a little more seriously. It's a continuing problem in the Canary Islands which are dependent on desalinization plants: "Rejected brine is a serious threat to marine ecosystems, causing negative effects on both flora…

The naive solution is to just dump the brine back into salton sea, its already too salty for marine life, so whats a little more salt? >flaunt its unequaled excellence by exporting alfalfa to all corners of the globe. really not sure if this is satir.

Your naive solution just creates an even more gigantic stagnant stinky mess of a Salton "sea". The entire point is to reengineer the salton sea as a beautiful ecosystem and lake by diluting all the salt with 5MAF of RO desalinated water. The added benefit is huge economic revitalization of the entire area. Plus, because of the value of minerals in the brine, and the cost-effectiveness of solar power, it is not as expensive and crazy of an idea as one might think.

Re: A vision for the alleviation of water scarcity in the US Southwest

#55

Post by 0xNotMyAccount »

mikeyouse wrote: post #26
nickparker wrote: post #6

Earlier quoted context omitted.

> RO desal splits the incoming ~3% salinity stream into two halves, one fresh and one ~6% salinity. This concentrated brine is fed to adjacent brine processing facilities (ideally in both countries) that exploit the region’s abundant solar and geothermal energy to extract potentially millions of tonnes of lithium, sodium, magnesium, chloride, and other metals found in sea water. The resulting depleted brine is piped…

We just simply don't need that much brine for useful minerals -- it's a huge cost and you'll be left with massive piles of mostly useless salt. On one of my hard drives, I've got an engineering / construction plan for a moderately sized intake + discharge for a small RO facility that would've passed muster in Australia, which has pretty reasonable environmental protections. Round numbers - the intake would have cost…

This is doable. Many coastal wastewater systems already have large pipes that extend miles to sea (1), and that's a rounding error compared to the many more miles of pipe routing sewage to the plant (2, pg A-3)

(1) https://www.wateronline.com/doc/new-10-mile-long-sewage-tunn...

(2) https://www.sandiego.gov/sites/default/files/ploovol4_15.pdf

Pipes tend to last a long time, in large part because it's relatively straightforward to manage the chemistry problem in the pipes.

Re: A vision for the alleviation of water scarcity in the US Southwest

#56

Post by School-Cotton »

alexb_ wrote: post #49

Just charge people for the natural resources of the country via taxes. Resource and land taxes solve basically every single problem in the current American economy yet people do not want to even think about doing it.

Plenty of people are thinking about it, including you.

The issue is that the American makes it structurally impossible to pass any major reform on any controversial topic.

Re: A vision for the alleviation of water scarcity in the US Southwest

#57

Post by obblekk »

hnmullany wrote: post #3

Apart from whether the economics make sense brine disposal from desalinization is a big issue. Waste with high salt concentrations can wipe out marine life - it would be nice if this piece took the issue a little more seriously. It's a continuing problem in the Canary Islands which are dependent on desalinization plants: "Rejected brine is a serious threat to marine ecosystems, causing negative effects on both flora…

There should definitely be a plan for the brine.

I'm optimistic we could:

* Build ocean pipelines that disperse brine over much larger volumes of water to minimize impact on wildlife

* Dump the brine water in engineered desert fields where it will evaporate and deposit salt reserves.

In general, we should be aware of the whole lifecycle of a solution, and optimistically believe we can solve each problem with more work.

Re: A vision for the alleviation of water scarcity in the US Southwest

#58

Post by tracerbulletx »

floatrock wrote: post #10

So basically pump seawater up from the Gulf of California across the border over a flat floodplain to the Salton Sea (south of joshua tree) and use cheap PV to run desalination plants that will restore one of our biggest environmental disasters https://99percentinvisible.org/episode/sea-worth-salt back into a vacation hotspot greater than Palm Springs. Costs of the PV and desal (relatively cheap but still absurdly ex…

We're already doing that with dams.

Re: A vision for the alleviation of water scarcity in the US Southwest

#59

Post by shermantanktop »

MostlyStable wrote: post #51

I know he inputs some numbers, but I am just supremely skeptical of them. If solar + batteries + RO plants could produce water at a price that made agriculture economically viable, then I just don't see how it wouldn't already be happening. Or at the very least be being proposed more broadly than some random guys blog. If I understand correctly, it is his plan for extracting value from the brine which represents the…

Agree with the skepticism, and furthermore if this were such a killer moneymaker you'd expect multiple commercial efforts in this space already.

But this is California - there may be reasons that are not economic or technical that have prevented anyone from trying to develop or pursue such an idea. The concentrated salt-brine discharge, for example, may be impossible to get environmental approval for at these volumes.

Re: A vision for the alleviation of water scarcity in the US Southwest

#60

Post by messy »

bilsbie wrote: post #23
hnmullany wrote: post #3

Apart from whether the economics make sense brine disposal from desalinization is a big issue. Waste with high salt concentrations can wipe out marine life - it would be nice if this piece took the issue a little more seriously. It's a continuing problem in the Canary Islands which are dependent on desalinization plants: "Rejected brine is a serious threat to marine ecosystems, causing negative effects on both flora…

It sucks you guys home in on some weird issue for every promising technology. He literally addresses brine in the article.

They provide some detailed and constructive thoughts. What exactly does your comment provide? Some sort of complaint which could be solved by yourself by not going into the comments or not reading theirs, hope this helps you in the future.
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