[jmyeet]

At least this article notes that the vast majority of water usage is agriculture. This isn't something cities could or should solve by switching to (expensive) desalination to effectively subsidize agriculture. Most notably, alfalfa is mentioned here as farmers are going to have to switch to less water-intensive crops.

Decreasing alfalfa production may well impact the ability to feed cattle. In the short term, that's actually fine. It may just force more beef production, which will be good for costs (again, in the short term).

But this article makes the same mistake so many make: blaming this on climate change. It's not. It's simply usage. See Figure 2 on page 10 [1]. Additionally, water projections were made at a high point of water inflows that simply haven't been realistic since.

In short, we're using too much water and farming is going to have to take the hit.

[1]: https://www.usbr.gov/watersmart/bsp/docs/finalreport/Colorad...

[creatonez]

> But this article makes the same mistake so many make: blaming this on climate change. It's not. It's simply usage. See Figure 2 on page 10 [1].

> [1]: https://www.usbr.gov/watersmart/bsp/docs/finalreport/Colorad...

I don't trust that a 2012 report is up to date on our latest climate modelling, or even that this is a climate-adjusted projection at all. Actual data past the point of publishing has not followed this graph. Anything more recent that supports your claim?

Your source also says:

> In the long-term (2041 through 2060), the futures that consider the Downscaled GCM Projected water supply scenario [not shown], which incorporates projections of future climate, show a high inability to meet resource needs, regardless of the demand scenario and the operation of Lakes Powell and Mead.

[COGlory]

That figure is simple supply and demand. It shows supply staying roughly steady, and demand increasing drastically every year. Climate has nothing to do with that calculation (although it's possible it's exacerbating it, this was going to be an issue regardless).

[kortilla]

It doesn’t need anything more recent. This has been a known issue for decades regardless of climate change.

[joe_the_user]

But this article makes the same mistake so many make: blaming this on climate change. It's not.

Sure, you have a whole host of local disasters caused by local mismanagement (agricultural water use, failure to prevent fuel build-up in forests, etc). And the local mismanagers point to climate change to say "don't blame us".

However, when discussing these things in the large, you have people pointing to the local mismanagers and saying "don't blame climate change", which is pretty much the reverse sort of bullshit. Of course climate change has made these already bad problems worse. Of course, the first way the problems of climate change appear is this making bad problems worse thing. What else would you expect? That climate change appears in a nice, neat way that lets you exclude other causes? Ha (except that results aren't funny at all).

And this mutual finger-pointing works well to prevent anything being at any level.

[vwoolf]

The desalination plant solutions a "let's do both." https://californiaglobe.com/articles/california-coastal-comm...

Charge market prices for water and build desalination. Create abundance.

[cplusplusfellow]

If only people understood this concept. In my home town city council are bickering about whether to allow additional density to be build on already commercially zoned lots based on whether they force 10 or 12% if the units to be “affordable.”

They are bickering over whether 40 units of a building might have a net decreased rent of $200 a month and instead may get 0 units built instead of 400. The 400 units would likely reduce the rent in the area by more than $200.

Create abundance and then let the market set the price and be happy.

[kortilla]

That’s another form of the “both sides” type of fallacy. Desalination is an extreme unnecessary compromise to deal with obscene waste in agriculture.

[foolfoolz]

the largest desalination plant in the u. s. can serve 110,000 homes. we would need 30 of them to make a significant dent in just the LA area. we will all be long dead before 30 new desalination plants are operational in california

[macintux]

Desalination requires energy and creates waste. Perhaps we should live within our means instead.

[Yoofie]

> Desalination requires energy and creates waste.

This is true for basically every human endeavor.

[coryrc]

Dams literally generate energy and provide water consistently.

[selectodude]

And lay waste to entire river ecosystems.

[obmelvin]

Do dams provide water? Don't they use the water provided by a body of water?

[dredmorbius]

By controlling and regulating water flow, dams make available more water than would be available from an unregulated water flow.

As noted by others, this isn't entirely cost-free, and there are ecological impacts. Still, on net, many dams do provide real benefits.

[jshen]

You are advocating for famine and war.

[adrianN]

Or they're advocating for eating less water intensive things. If you for example grow wheat instead of grapes or almonds your likely reduce global famine a little bit.

[macintux]

Or growing water-intensive crops in water-plentiful regions of the world.

[jshen]

Aka deforestation.

[jshen]

That’s meat, it’s the most water intensive. How much do you want to get that she/he eats meat everyday? What about you?

[adrianN]

I eat meat whenever my local supermarket has a piece of organic meat on sale because it would otherwise get thrown away. That's once or twice a week. Less meat consumption in general would probably be good not only for the environment but also for public health.

[pjc50]

If you charge both the agricultural and residential users the same price, the agricultural ones go out of business. That may well be necessary, but they're politically well connected.

[s0rce]

Who pays for it though? Market price is way below desalination price.

[willcipriano]

Idea I've had, solar power a desalination plant, pumping the water into a pumped storage reservoir, then water crops from it at night to reduce evaporation and produce energy when the sun isn't shining.

[prawn]

Is there an issue with trying to locate solar (often in flat areas) alongside pumped storage (would that be in a mountainous or at least hilly area)?

[cwalv]

> This isn't something cities could or should solve by switching to (expensive) desalination

In 2015, the Southern Nevada Water Authority completed a "3rd straw" into Lake Mead to safeguard water availability, at a cost of $817M [1], which is enough to cover the power costs to desalinate Nevada's CO river allotment for ~23 years. It's been a while since I looked into it, but I once ran the numbers and the cost of that 3rd straw was comparable to the cost of building a solar power plant that would generate enough electricity to cover the desalination for NV's allotment as well.

Notes:

Nevada's allotment of water from the Colorado River is 279k acre ft / yr (actual use is 242k acre ft / yr in 2021) [2]. There are desalination systems available that require 3452 kw / acre ft [3]. Southern Nevada wholesale rate of $.37 / MWh [4].

[1] https://www.nps.gov/lake/learn/the-third-straw.htm [2] https://www.lasvegasnevada.gov/News/Blog/Detail/lake-mead-wa... [3] http://www-formal.stanford.edu/jmc/progress/water.html [4] https://thenevadaindependent.com/article/nv-energy-introduce...

[dghlsakjg]

Desalination traditionally needs a source of water to desalinate. Then you need somewhere to put the brine.

The ocean is traditionally the answer to both these needs. Nevada is not a good candidate for a desalination plant.

[cwalv]

> Nevada is not a good candidate for a desalination plant.

No, but it's a good candidate for a solar power plant, and the water source is shared with major coastal metro areas. You'd of course want to move the power to the coast; an amount of water equivalent to that produced by desalination could be withheld upstream, in Nevada.

That said, I still think they made the right move building the 3rd intake, even at such expense. That intake is below the "dead pool" level, while the other 2 are not .. so even if ppl can't sort things out politically and continue to draw the water down past the point that it won't flow over the dam, NV will still be able to draw their "allotment". And of course, it's very hard to build desalination plants in CA, no matter how much sense it makes.

[brandmeyer]

> Southern Nevada wholesale rate of $.37 / MWh [4].

Typo. That should be $37/MW-hr, not $0.37/MW-hr (article quotes $36.67 / MW-hr)

[seanmcdirmid]

Desalinated water would have to be pumped uphill along way for the coast. Desalination makes much more sense for coastal communities in that regard, but it won’t be that useful for agriculture.

[cwalv]

Or you could use transmission lines to push the electricity to the coast, and just keep the equivalent water from flowing downstream.

[ericbarrett]

I drove into Sacramento last year in late summer. There are flooded rice paddies just outside the city. Rice paddies! In California! In the middle of a historic drought!

[swatcoder]

FYI: Sacramento is a natural delta and most of the water you saw still continues on through the water supply.

While one can always suggest more economical uses of water than any particular use/crop, the reality of what’s going on there might be different than your intuitions.

https://rice.ucanr.edu/Water_Use_by_Rice/

[ericbarrett]

34" of consumptive water use (per your source) across the thousands of acres planted is simply unsustainable—plenty of crops use half that, even with 19th century techniques that agribusiness insists on. Also that's more than half of the draw (again per your source) so "most" is quite the exaggeration. And the majority of the loss here is simply surface evaporation!

[swatcoder]

Sure. I wasn’t meaning to defend it and tried to leave room for that. I don’t have the expertise to speak either way.

I just thought it would be constructive to surface some of the detail behind what you reported in your original comment. People’s imaginations can run wild when you talk about California!

[dredmorbius]

I'm not versed on specific water usage by rice paddies but am aware that:

The inland Central Valley of California was historically a seasonal or episodic lake. The Great Flood of 1862 saw 3m (10 ft) of water dumped on the state over 43 days from December 1861 through January 1862, followed by a warm storm melting much of the snowpack:

The entire Sacramento and San Joaquin valleys were inundated. An area about 300 miles (480 km) long, averaging 20 miles (32 km) in width,[21] and covering 5,000 to 6,000 square miles (13,000 to 16,000 km2) was under water.[15] The water flooding the Central Valley reached depths up to 30 feet (9.1 m), completely submerging telegraph poles that had just been installed between San Francisco and New York. Transportation, mail, and communications across the state were disrupted for a month.[22] Water covered portions of the valley from December 1861, through the spring, and into the summer of 1862.[15]

https://en.wikipedia.org/wiki/Great_Flood_of_1862

Much of the valley still floods seasonally, with designated flood zones such as the Yolo Bypass, between Sacramento and Davis.

A key problem within the central valley has been groundwater loss resulting in subsidence exceeding 15 m (50 feet) in places. Flooded paddies might help contribute to groundwater recharge.

Much of the paddy water is through-flow, which I'd presume returns to river flows. What the impacts of ag practices (fertiliser, pesticides) are I'm not sure. There will also be evaporative losses, of course.

I'd like to see a net impact / net flows analysis. The picture's likely more complex than a brief glance from the highway would afford, however.

[gedy]

No no it's because you are flushing your pee and have a patch of grass in front of your condo. Gotta regulate that first before we talk about inefficient farming. /s

[julienchastang]

> But this article makes the same mistake so many make: blaming this on climate change. It's not. It's simply usage.

See "Characterizing Drought Behavior in the Colorado River Basin Using Unsupervised Machine Learning"[0]. The journal article states: "The range of possible climate change considered here, regardless of ESM model, does point to a hotter CRB [Colorado River Basin] with large changes in the timing and magnitude of runoff, evapotranspiration, and soil moisture that will present challenges in managing water resources in the future."

[0] https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2021EA00...

[yumraj]

> Decreasing alfalfa production may well impact the ability to feed cattle.

A substantial portion of alfalfa is exported to China [0]. So, at the very least that portion can be eliminated without any impact on domestic US cattle feed.

[0] https://hayandforage.com/article-3388-thank-china-for-record...

[Jistern]

From 2005 to 2015, Israel changed its entire water system by building desalination plants.

Like Central and Southern California today, Israel used to issue similar dire warnings about freshwater supplies running dangerously low. These days, believe it or not, Israel now exports freshwater. Yes. tiny, little, arid Israel exports freshwater to neighboring Jordan.

Freshwater, like agricultural products, seems to be a product we can now cheaply and easily produce in abundance.

Sure, taking some water from farmers is an option too. But is it viable? I don’t know. Obviously voters living in the conurbation from Los Angeles, California to San Diego, California could vote in politicians who promise to do this. But once in office would politicians actually follow through on such a promise? I doubt it.

This seems like a very tough battle to me because many California "farmers" are extremely wealthy. Some California farmers are billionaires with a "b". If extremely successful businessmen with many thousands of millions of dollars want to keep receiving free water, they will probably very cleverly spend vast sums of money to do so.

Here are two apparently feasible options.

First, we are on the cusp of abundant, cheap renewable electricity (from solar and wind) which, of course, will lead to the potential for cheap desalination.

Like the aforementioned Israel, Carlsbad, California (near San Diego, California) already relies on desalination for much of its water needs. I think I read that residents there pay an extra $5/month to $10/month per person for desalinated water compared to what they were paying for imported fresh water.

Second, I assume the discharge water from washing machines could easily be used to water most of the landscaping in Southern California.

I've watched a few videos on YouTube. Apparently one simply needs to change the type of laundry detergent used so it would be safe for the landscaping, install discharge pipes from the washing machine to the landscaped areas, and control the system with computer to ensure the landscape isn't over-watered or under-watered.

The Los Angeles Times has become a terrible newspaper. COVID has receded from the front page, therefore they need some more bad news to sell. "We are running out of water!!!" is what they are selling these days.

In other words, this entire subject is "much ado about nothing." In other words, this is doom and gloom, "the sky is falling" nonsense.

[matkoniecz]

> Second, I assume the discharge water from washing machines could easily be used to water most of the landscaping in Southern California.

detergents used for washing likely make it a bad idea

[bearhall]

tell us you didn’t really read the parent without telling us you didn’t really read the parent

[Jistern]

Thank you.

[nr2x]

Not all climate change is global warming. Our actions change the environment in numerous, and often unpredictable, ways.

[bcrosby95]

Desalination isn't that much more expensive than reservoir water. I wish urban areas would just build 'em and look at farmers and the rest of the country and say "OK now what?"

[matkoniecz]

Can you provide any source for that? It seems obviously wrong given both capital and maintenance costs.

[twelfthnight]

This reference agrees with you in the short/mid term (to your credit, which you explicitly mention), but states in the long term climate change is the most important factor, regardless of demand. Taking action against alfalfa is a sensible thing to do right away, but won't address the looming crisis:

> In the near-term (2012 through 2026), water demands are similar across scenarios, and the largest factor affecting the system reliability is water supply. In the mid-term (2027 through 2040), the demand for water is an increasingly important element in the reliability of the system, as are assumptions regarding the operations of Lakes Powell and Mead. In the long-term (2041 through 2060), the futures that consider the Downscaled GCM Projected water supply scenario, which incorporates projections of future climate, show a high inability to meet resource needs, regardless of the demand scenario and the operation of Lakes Powell and Mead. "

[ErikVandeWater]

Serious question: Have climate scientists previously been able to accurately predict climate changes decades away on a regional basis?

[twelfthnight]

Not an expert but here's what I found from a little research:

It's hard to quantify, but it does seem like regional predictions are less accurate than continental, and predictions about rainfall are less accurate than temperature. However, predictions of rising temperature are essentially guaranteed.

> There is considerable confidence that climate models provide credible quantitative estimates of future climate change, particularly at continental scales and above ...

> Confidence in model estimates is higher for some climate variables (e.g., temperature) than for others (e.g., precipitation).

> Over several decades of development, models have consistently provided a robust and unambiguous picture of significant climate warming

Sources:

[1] https://oceanservice.noaa.gov/education/pd/climate/factsheet... [2] https://archive.ipcc.ch/publications_and_data/ar4/wg1/en/faq...

[scythe]

In terms of temperature, yes. Early climate models correctly predicted that warming would be concentrated at the poles, for example:

https://en.wikipedia.org/wiki/History_of_climate_change_scie...

>Also in 1969, Mikhail Budyko published a theory on the ice–albedo feedback, a foundational element of what is today known as Arctic amplification.

This is generally confirmed by observations, as seen in the graph:

https://en.wikipedia.org/wiki/Polar_amplification

I assume four decades should be enough. I don't know about precipitation modeling, that stuff's really hard and the variance is huge.