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Extreme heat, drought will permanently scar California and its social fabric

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141–150 of 195 posts

Re: Extreme heat, drought will permanently scar California and its social fabric

#142
post #61
post #28

Quick Google stats: There are 13M households in California. Average household consumes 0.5-1.0 acre-feet of water per year. It costs $419 per acre-foot for desalination. California has a discretionary budget surplus of $49B. Thus: It would cost $2.7B-$5.4B per year to provide desalination-based water to all Californians. With the current budget surplus, we could provide 100% of California's living water needs for 10-…

> acre-feet Being European, that's the weirdest unit of volume, I've ever seen.

Googling research papers on the subject of European irrigation, I'm mostly finding water usages quoted as mm/yr. Cultivated land area seems to be discussed, explicitly but often implicitly, in hectares. But I'm having trouble finding statements or graphs that show mm/yr/ha or mm/ha.

Unless I'm missing something (and I very well may be), I'll take acre-feet over mm/yr. acre-feet seems a more useful standard compound unit for discussing large scale (agricultural, industrial, etc) water usage, even if the underlying units are more archaic. If you're going to drop or leave implicit one of the three dimensions, time seems like the much better choice than area.

But maybe I'm biased by familiarity (and utter lack of expertise), or maybe I'm just wrong about the standard terminology. I need to get back to hacking, otherwise I'd keep digging....

Re: Extreme heat, drought will permanently scar California and its social fabric

#143

California is next to the ocean, so if we really wanted to secure the water supply we have technological answers available. Nuclear desalination has been used at scale across the globe for decades, and it's not hard to imagine a less centralized solution powered by solar or wind. https://www.iaea.org/topics/non-electric-applications/nuclea...

Oh the typical techie solution to environmental problems. We can solve this with tech! Wait until the aquifers under North America run dry. That's where most irrigation pump up their ground water from. A few dry rivers and smaller lakes are nothing compared to what's going to happen. Forget your desalination plants. https://en.wikipedia.org/wiki/List_of_aquifers_in_the_United... And it's entirely predictable. In fact…

Do you know of any evidence that North America, as a whole, is using more water than is falling on it? Because that's not something I've heard about thus far.

Just because we have a significant drought (or possibly "climatic shift to a drier climate") in the Southwest doesn't mean that we have the same problem everywhere in the US.

Re: Extreme heat, drought will permanently scar California and its social fabric

#145
post #49
post #28

Quick Google stats: There are 13M households in California. Average household consumes 0.5-1.0 acre-feet of water per year. It costs $419 per acre-foot for desalination. California has a discretionary budget surplus of $49B. Thus: It would cost $2.7B-$5.4B per year to provide desalination-based water to all Californians. With the current budget surplus, we could provide 100% of California's living water needs for 10-…

I disagree that we should build desalination, even if we can "afford" it. There are agricultural users of water paying astronomically lower prices due to long standing water rights. It would almost certainly be cheaper to pay them to conserve (grow less of water-wasting crops, leave fields fallow, or upgrade to more efficient drip irrigation). The urban water use is around 20%, making them pay billions for this 20% m…

>The urban water use is around 20%

which means that around $20B/year will cover desalination of all the water consumed in California solving all the environmental issues caused by water consumption, and all those problems probably would become close to nonexistent even if we cover only half the needs at $10B/year. Especially considering that climate change would be making situation only worse, and thus desalination is unavoidable anyway.

Re: Extreme heat, drought will permanently scar California and its social fabric

#146
post #96
post #38

I am curios how much the excess consumption of water influences the low water levels. I do not get the feeling that the inhabitants of California are particularly saving any water. I guess that there is big potential to save water.

In LA watering of non-trees is down to 16min max a week? OFC beverly hills isnt complying but they are technically their own city

In my water district we can run sprinklers for 8 minutes per week. Not that I'm complaining.

Re: Extreme heat, drought will permanently scar California and its social fabric

#147
post #31

Earlier quoted context omitted.

The state needs to start overruling the local NIMBYs and build the desal plants the rest of the state needs. And the regulators need to chill out: https://www.reuters.com/world/us/california-regulator-reject...

We don't need desal, we have plenty of water for people to live here. The vast majority of water goes to agriculture. If we were just a bit more selective in what we farmed, we could reduce our water usage by a significant amount.

> We don't need desal, we have plenty of water for people to live here.

For how long?

Why are you advocating for scarcity? Scarcity causes conflict. We live in a world where we don't have to fear scarcity. Why not advocate for desal AND better water use?

Re: Extreme heat, drought will permanently scar California and its social fabric

#148
post #19

This is partially why I think the risk of homeownership is largely being understated. You may have entire communities that become uninsurable even long before an actual natural disaster occurs, and it becomes very difficult to cash out refinance or sell.

I think it's already happening in New Orleans. At least that was the impression I got when visiting. I think it can be difficult to insure a business or home affordably in the area. Seemed like a lot of storefronts were just empty. Perhaps I just went at a bad time of year (late nov).

What year did you go? If it was last year then New Orleans was still recovering from Ida.

Re: Extreme heat, drought will permanently scar California and its social fabric

#149

Collecting fog electrostatically is 2x more efficient than desalination. It works by ionizing the droplets in the air and collecting them on wire meshes: https://www.science.org/doi/10.1126/sciadv.aao5323 . The technique also doesn't produce tons of salt waste that you have to dispose of. It's a potential solution for towns/cities next to the ocean. Desalination is cheap enough already if we get desperate. It won't b…

The difference with this is it reduces the water available to fall further downwind, and could thus cause other issues: it's effectively zero-sum on moisture, while desalinating ocean water is positive-sum (though, yes, it has a waste issue).

Re: Extreme heat, drought will permanently scar California and its social fabric

#150
post #122

Collecting fog electrostatically is 2x more efficient than desalination. It works by ionizing the droplets in the air and collecting them on wire meshes: https://www.science.org/doi/10.1126/sciadv.aao5323 . The technique also doesn't produce tons of salt waste that you have to dispose of. It's a potential solution for towns/cities next to the ocean. Desalination is cheap enough already if we get desperate. It won't b…

this is really interesting, i live in the bay area, are there any consumer product for this, or is it typically only economically feasible at scale?

I'm not aware of a consumer product. The authors of the paper started this company: https://www.infinite-cooling.com/. It looks like it's targeting industrial processes (cooling towers) where the collection efficiency is really high. Makes sense, why do B2C when you can do B2B w/ million dollar contracts...

I'm personally looking into making something that can continually top up something like a 500 gallon water tank every night (when humidity is high) on a residential property. These tanks are prevalent in the drought-stricken, coastal community I live in. You need about 2200 gallons/person/month, of which only 15 gallons/person/month is used for drinking water. So if you can continually collect water throughout the month and have the space for a tank (about the size of a truck bed) then it should be possible to supply most of your water usage off the grid and in a way that isn't draining reservoirs.

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