Can desalination quench agriculture’s thirst?
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Charging agriculture what water currently is worth -- or allowing them to sell the water they get to those willing to pay more -- would be much more effective than desalination. The current set up in the US is guaranteed to be massively economically inefficient.
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Desalinization seems like an ideal application for solar power; it's not a big deal when the sun goes down.
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Interesting possible cost reductions and looks increasingly practical. However, if the rainfall does not come, where do even the brackish aquifers refill? Difficult to pump a dry aquifer.
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Let's bury the fatal flaw in the second to last paragraph.
Hueco-Mesilla Bolsons Aquifer
"Stabilized," not recovered.
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Did Betteridge create a law of headlines?
Are we through with the rhetorical questions?
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Desalination has been, and will continue to be, a focus of a lot of technological development. I'm not saying that this solar-powered device that does not clog from salt can scale up. It would be nice if it could. Very intelligent efforts continue.
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No. Most of California's water problem with the Colorado river is that the water rights holders there are growing feed crops for dairy and other ranching operations.
The more fundamental problem isn't water but labor. California grows a lot of high water crops. We do that because we grow most of the nations high labor crops because we have half of the nations farm workers - so any high-water, high labor crop winds up here. Other states have concentrated on low-labor, highly automated crops.
So rural communities around the country have died off because their ag labor got automated. CA picked up all of the high labor crops because we're not hostile to immigrants. That pushed a lot of high water crops into a state without much water, crops that could be redistributed back across the country, along with the associated labor to revitalize these rural towns. But that won't happen in a climate of mass deportation.
National policies that forced crop diversification across states would solve a lot of CAs water problems by creating competition which would likely cause many farmers to shift to crops better suited for a dry climate.
The more fundamental problem isn't water but labor. California grows a lot of high water crops. We do that because we grow most of the nations high labor crops because we have half of the nations farm workers - so any high-water, high labor crop winds up here. Other states have concentrated on low-labor, highly automated crops.
So rural communities around the country have died off because their ag labor got automated. CA picked up all of the high labor crops because we're not hostile to immigrants. That pushed a lot of high water crops into a state without much water, crops that could be redistributed back across the country, along with the associated labor to revitalize these rural towns. But that won't happen in a climate of mass deportation.
National policies that forced crop diversification across states would solve a lot of CAs water problems by creating competition which would likely cause many farmers to shift to crops better suited for a dry climate.
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Precisely - reverse osmosis has a down side: pulling fresh water out of slightly salty water also creates significantly saltier waste water - which must then be disposed of. Where will the saltier waste water go - back into the aquifer? Into rivers to deposit salt in tot soil?
The desalinization plant in Oceanside, California notes that:
Source: San Diego County Water Authority Desalination 101 (The nuts and bolts)
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Even if it didn't clog from the salt, disposing of the salt will be onerous. Most people cannot imagine the sheer scale of ag water use, desal is a pipe dream (ba-dum tish!).
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I think this would allow pumping progressively deeper salty aquifers; there's a lot of salt water down there -- much more than fresh water even in areas of the US that haven't been pumped.
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BananaWarrior
Ars Praetorian
Yes, it's just a matter of energy. This is why we need nuclear in addition to solar, hydro and wind power going forward.
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I've seen this argument come up every now and then when it comes to water availability and scarcity. On paper it makes sense, but when you think about it some more it brings a whole slew of difficult questions.
Scarcity driven pricing on water largely means that when there isn't a lot of water, the price of water will go up. Precisely when people need the water the most, most will be priced out. They will literally not be able to afford a necessity that let's them stay alive. As with many issues facing the world today, the wealthy will largely be able to continue on with their lifestyles as they see fit while those who cannot afford the water will go through significant and potentially fatal struggles. Or only the wealthy farmers will be able to afford to irrigate the more expensive crops.
Then there are the crop prices themselves. If you use pricing as a means to control water use, some farmers may scale back operations, but others may simply increase their prices and pass it on to consumers. And if the market demand for a water intensive crop never really goes away, then things just get more expensive which nobody really likes. The problem won't really get solved since water consumption doesn't change and you just add another group of middle men to pay before the crop reaches the kitchen table.
Water markets will really get messed up too. Water license holders may find it more profitable to sell water to farmers than to grow crops. In such conditions, a water license would become a license to print money because humans cannot live without water. You can hold the license and keep on renewing it basically forever because you are certain to generate enough income to pay any nominal renewal fee. You will also run into problems when water licenses end up being in the hands of a few (oligarchy) or singular entity (monopoly). We have already seen what this has done to the US economy and politics for what I would call non-essential goods and services.
I do agree that current water regulations need to be revisited in light of climate change and strained water resources, but I don't think a market solution is it.
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Water trading has been tried in Australia. All it's done is make some people rich who shouldn't hold water rights or allocations in the first place.
https://www.mdba.gov.au/water-use/water-markets/water-trade
Bloomberg - The Water Trade Is Booming — and Sucking Australia Dry
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There's a limit to how deep you would want to drill when targeting deeper saline aquifers. Eventually they get so salty the water is more like the brine byproducts of desalination. The water also has a bunch of nasty stuff in it like dissolved heavy metals and radioactivity of all things. The oil and gas sector calls it "produced water" when they bring the stuff up from pumping oil and it makes a big mess when it gets spilled.
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All aquifer desalination does is kick the drained aquifer can further down the road. If water usage isn't matched to local rainfall + imported rainfall, all the aquifers will eventually be empty. May take a few generations but that is the end result.
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Just more can kicking down the road, like fracking for oil, once its extracted then what ? (ignoring the toxic nature of both industries. This will be energy intensive, no matter spurious claims of using renewables, as though the construction of renewables isn't heavily resource dependent.
and as it gets hotter and hotter ? more magic water may help but you need to build shade structures then what , inside ? mega structures covering millions of acres with solar panels above, then mega AC units to cool the air ?
316 Million pounds of food thrown out over Thanksgiving. Food needs to be WAY more expensive ie scarce (by closing farms such as these) and rationed out when necessary so the poor are afforded equal access to the rich or keep doping this until the entire thing collapses from human hubris
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You're on the right track there. My thought was, "What happens to all those desal plants when the non-drought aspects of climate change makes just planting things in that region non-viable?"
Even if you have all the water in the world, you can't control the temperature. The odds are that most of the arable land we use for agriculture today will be majorly altered in their ability to produce what they produce today, assuming they're able to produce anything at all given the heat or winds, or what have you that changed enough to force all crops it once grew to move to more hospitable climates.
Betteridge's Law seems to apply here. It's not JUST the water/drought that causes problems with farming. It's the whole climate. After all, you're not going to be raising tropical fruits in a desert getting less than a few inches of rainfall a year unless you have the extra water to do it.
So at some not too distant time, you'll probably not be able to grow the plants, even if you had the water to do it.
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Yep, exactly what came to mind for me. Central valley in CA has some areas that have sunk 29' mostly because of overpumping. I don't think the problems are a bit more than desalination in those areas - just being able to use another aquifer they couldn't before is but a shell game.
Different story from the ocean of course, definitely worth investing in the tech there when paired with renewable sources.
Unrelated, but I'm a little surprised farming is behind thermoelectric in usage (though no idea what the capture rate in that application is).
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The problem is not that it costs $800/acre-foot to desalinate this water, the problem is that somebody else is able to obtain water at an absurdly below-value $3/acre-foot for unjustified reasons (history and seniority).
It's impossible to compete with somebody who gets their resources functionally for free (effectively subsidised by everybody else and the future) so the price of that food item stays artificially low, and there's no incentive to create actual solutions to the problem because there's no margins.
Subsidizing random people who ended up inheriting land from some dude who happened to yell "first!" a century ago is the very last thing we need in terms of water management, which is going to be a central point of conflict over the coming decades.
It's impossible to compete with somebody who gets their resources functionally for free (effectively subsidised by everybody else and the future) so the price of that food item stays artificially low, and there's no incentive to create actual solutions to the problem because there's no margins.
Subsidizing random people who ended up inheriting land from some dude who happened to yell "first!" a century ago is the very last thing we need in terms of water management, which is going to be a central point of conflict over the coming decades.
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Apparently, most desalination systems are designed to run continuously. Stopping and restarting flow causes problems.
There was a recent article about an MIT group developing a desalination system that could start and stop. But that is not how existing systems work.
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Water wars have already begun. Yemen, Sudan, actually many of the conflicts in sub-saharan Africa are directly or indirectly related to water access. Desal overlords will make the mafia and even your cable access overlords look like "nice folk".
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The Brackish Groundwater National Desalination Research Facility sounds like the cover facility for Wildfire in the Andromeda Strain...
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You started with an economic argument why crops are here and then ended by ignoring an economic argument.
Agricultural labor in CA is expensive, by national standards. Transportation can also be expensive, depending on crop. So you have to argue that the cost of desalination plus the opportunity cost of lower labor and local supply chains is less than the benefits of an expanded growing season. And it presumes that consumers ever see those savings. Crop prices in CA are down about 20% across the board this year. Did anyone notice those savings? Or were they captured as profits by the intermediate layers of the supply chain - distributers, grocers?
The argument for large scale industrial farming is that it lowers costs. But consumers don't seem to bear the benefits of that. The current price for class I milk from farmers is about $1.10/gal. The national retail price for milk is $4.10/gal. $3/gal is a LOT to cover pasteurization packaging and distribution. I'm not convinced that the lower wholesale cost is translating to lower retail ones, rather than just higher profits for the intermediates.
CA is the largest dairy state by a factor of 2, and I'm pretty sure you can run dairy operations anywhere in the US year round. Wisconsin is hardly a semi-tropical environment. But large dairy operations use a LOT of undocumented labor, which is why dairy production is moving to all of the southern border states (the ones without much water, but lots of undocumented labor) from the upper midwest. Herd sizes in the midwest average maybe 200 cows - small enough there is still grazing operations that don't require water capture. In the border states it's 2300 cows and they're 100% feedlots, and entirely dependent on water capture in the part of the country with the least amount of water.
The only reason for this shift is ag labor access. That's it. And the cost to access that labor is pumping from aquifers or the Colorado river. And then we take that water and ship it around the country in the form of milk. In case you were wondering, in the midwest a gallon of milk requires maybe 50 gallons of captured water to produce. In the southwest it's about 500 gallons because there's no grazing, feed crops are entirely irrigated, and so on. So yeah, for want of ag labor, we do one of the most water intensive bits of agriculture in the desert.
And it's not just dairy but all kinds of crops that migrate like this, for the exact same reason.
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No, you won't see a 20% drop in retail prices when there is a 20% drop in farm gate prices because, as you yourself admit, farm gate prices only constitute 25% of the final cost of the product. So in that scenario you'd only expect a 5% drop. If there's a bit of inflation in the other 75% of the expense you wouldn't even expect to see 5%. This isn't "higher profits for the intermediaries", it's just basic math.
You also seem surprised that 75% of the cost of milk has to do with bringing it to market. Well, don't believe me. If you think it's possible to buy milk from a farmer, ship it to where it's needed, refrigerate it along the way, comply with all necessary food inspections, advertise it, and sell it for less than $3 per gallon, then by all means you should start a milk store and find out how easy and profitable food retailing is!
California has 12% of the US population and 18.6% of the diary. It punches above its weight, but it's also not the powerhouse you make it out to be. It provides for Nevada which lacks a vibrant dairy industry (1% of the population, 0.2% of the dairy) and it has easy access to international trade. Dairy is a largely automated industry (we don't milk cows by hand, btw). You haven't really provided any convincing evidence for your thesis that illegal immigrants are key to California's success, and even if they are that success is modest.
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If water is the limiting factor, why not use greenhouses to get the evaporated water back? One could also use hydroponics, as someone commented above, to avoid losing water in the ground. These solutionswork, but require a bit more infrastructure (China is big on greenhouses). Depending on the region, temperature may be an issue, but I imagine you can take water vapor and let it condense elsewhere, that would still be less energy intensive than desalination.
One can also plant crops that require less water. Corn needs a lot of water.
One can also plant crops that require less water. Corn needs a lot of water.
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Yes I saw that, the weird thing is they also have "versus around 35,000 milligrams per liter"
So are they using metric or US imperial?
Surely they should use X smodges per thimbleful or something
I just looked up 1 acre foot = 1233481 liters, thus 1233 tonnes of water or in volume 1233^3 m of water. Gosh Metric is difficult
Actually looking at the imperial measurements I found this
https://www.unitconverters.net/volume/acre-foot-to-break.htm
Break! Never heard of that before, I tried googling it but couldn't find anything, does it exist or is this just nonsense?
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just need loads of batteries.
also you bet someone will be fly tipping salt/brine. then they wonder why they can't grow shit in certain places.
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Americans waste 40% of our food. That's 40% of land that could've been left to nature for plants to grow to sequester CO2 and support natural ecosystems. It is also 40% fossil fuel burned for agriculture that went into producing CO2 and food that ends up as waste and produces planet heating methane. I was watching an episode of food production on Modern Marvels that showed one of the buffets in Las Vegas throw away 3000 lbs of food a day. Capitalism's measure of success is that we bring in more money than we spend, while externalizing the damage to the planet and fossil fuel has supercharged this. Time and again industrialized nations fail to curb climate change and are parsimonious toward helping poor nations that did not contribute to the destruction of the planet. The lesson here is that we get ahead by damaging the planet. To heal it, we must include the cost of damage in our economic system. Doing so will reduce distortion such as wasting food, why we burn fossil fuel to move 4000 lbs of metal just to move 200 lbs of flesh and why we have millionaires/billionaires. These desalination efforts will only "help" one species harm the planet by producing more food to waste.
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It's expensive? Yes.
It's technically usable? Also yes.
It's competitive? Sometimes.
It depends on food price, which always change. As food rise on price, using desalination becomes competitive. Of course, certain crops and cultivation techniques are better than others in this scenario.
It has no economic sense to use water hungry crops.
Also, most water, in a regular scenario, ends evaporating or leach underground. Both can be partially recovered, so with a precise design, costs can be significantly reduced.
Yet... any work is always more expensive that not work at all, so areas that doesn't have water can't reach the cost of wet areas. It's just if the demand pushes us beyond our current water offer that new ways of cultivation will spread and optimize, so the difference cost could be less than we can imagine after optimizations.
After all, other steps of food management also add costs. Maybe after optimizations can have sense to cultivate in near places under dry conditions than far places on better water conditions because the extra cost of water management is overall less than transportation costs.
Currently it usually not, as water desalination is very expensive and transportation cheap due to cheap oil. But... In the future? Who knows.
It's technically usable? Also yes.
It's competitive? Sometimes.
It depends on food price, which always change. As food rise on price, using desalination becomes competitive. Of course, certain crops and cultivation techniques are better than others in this scenario.
It has no economic sense to use water hungry crops.
Also, most water, in a regular scenario, ends evaporating or leach underground. Both can be partially recovered, so with a precise design, costs can be significantly reduced.
Yet... any work is always more expensive that not work at all, so areas that doesn't have water can't reach the cost of wet areas. It's just if the demand pushes us beyond our current water offer that new ways of cultivation will spread and optimize, so the difference cost could be less than we can imagine after optimizations.
After all, other steps of food management also add costs. Maybe after optimizations can have sense to cultivate in near places under dry conditions than far places on better water conditions because the extra cost of water management is overall less than transportation costs.
Currently it usually not, as water desalination is very expensive and transportation cheap due to cheap oil. But... In the future? Who knows.
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I agree. I think people are desperately ignoring what's going on in places where aquifer depletion is already rampant. It's not just that fresh water is being pumped out in areas where it won't be replaced in thousands of years. Florida is a poster child of what happens when you over pump aquifers regardless of whether it's fresh or salt water. You get sinkholes everywhere. They collapse without warning and cause considerable damage when they do. People can and do die.
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It's not just that water would take a long time to replace. An aquifer can out-and-out collapse, eliminating void volume for water to return to. The capacity can be permanently reduced.
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