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One Way to Fight California's Drought: Desalt the Ocean (wired.com)
41 points by lxm on Aug 3, 2015 | hide | past | favorite | 57 comments



As I said the last time this came up:

It makes no sense at all to pay $2k an acre-foot for desalinated water in a state where millions of acre-feet are being used to grow alfalfa that sells for less than $400 per acre-foot of water consumed.

This isn't a lack of water problem, it is an poor governance problem.


> it is an poor governance problem

No, it's a poor pricing problem.

The price of water should be directly related to the cost of delivery and supply. Unfortunately, virtually everywhere, you are merely charged for the cost of delivery. If we tie the price of water to something like rainfall, we'll all be much better off. Inefficient use of water will disappear very quickly.


>> it is an poor governance problem

>No, it's a poor pricing problem.

And who do you think sets pricing regulations?


California prevents farmers from selling water across county lines and more. Farmers would certainly choose to sell the water if they could.

As for desalting the ocean, perhaps building aquifers to retain the run off from rains would be a better solution. They did a great deal of work to send all that water into the ocean, its time they redirected it to where it can stored and used as necessary.


We do that. They're called, "Reservoirs": Consider the Colorado River, where rain and snow runoff from mountains is diverted from that river and used for such things as agriculture. It's used so heavily, that the river does not run to the ocean any more and the resevoirs we've been using the river to fill up are at historical lows. So that's tapped out.

If you're thinking of using the runoff from local rains, consider that California is in a drought. Rainwater isn't going to be all that dependable. There are things called, "Aquifers" - the water table below ground. Rainwater is used to fill this up, and - well: those are also at historical lows because of wells.

Much of the rain that falls is actually evaporated up again, it doesn't run into the ocean.

So, we're still left with a problem of populations that don't have an adequate and cheap water supply. Uh oh.


Various entities in CA have spent a lot of money to prevent flooding, and in doing so they have made very effective systems that shunt freshwater right into the ocean. Because the water is very efficiently moved from streets to drains to cement rivers to whatever it doesn't get a chance to sink in, and that means that a lot of water is "wasted".

CA might be in a drought, but it still does get rainfall. Drought != no rain at all, it means less rain than usual.

If you don't get much rain, you have to do everything you can to prevent runoff. There's not much of that in CA and so there are problems. It's partially a drought, and partially bad water management that have caused the problems.


Agree wholeheartedly. To put concerns about pricing the poor out of their water, I'd agree with a subsidised rate for the first N gallons consumed per household each month. The subsidy could be made revenue neutral by funding it out of a tax on the un-subsidised portion.


Why isn't the price of water tied to the price of supply?


Thats not the way water rights work at all - eg, farmers get a percentage of the water from a given stream.

Check out SSC[1] for an in depth review of water policy in CA.

1. http://slatestarcodex.com/2015/05/11/california-water-you-do...


because water is a public utility and heavily regulated, and for good reason - you want to guarantee that everyone who needs water gets it, even if you are poor and unpopular. Of course that's vulnerable to pressure groups, in this case the agricultural sector who want lots of cheap water. Then again if it was all run privately with no regulation, all the water would probably be put in bottles and sold at 1000x the price.


Your comment shows an ignorance of how prices work. Companies cannot arbitrarily set whatever price they want.


No, but they will set the highest price the market can bear. It appears people are willing to buy bottled water at around 1000x the price per unit volume compare to tap water, so given a free reign companies would sell as much water as bottled water at that price as they could.

This is actually happening in California with Nestle's bottling operation where the oversight of their water use has been very lax.


You are being manipulated by a PR campaign. Nestle draws ~2000 acre-feet a year. It's a rounding error. Same thing with shutting off the water while you brush your teeth, restaurants not serving water until you ask for it, and so on.

The uses that matter are agriculture, agriculture, agriculture, industrial (e.g. power plant cooling towers), and far off in the distance outdoor domestic / commercial use (pools and lawns). (Also, if you consider it a 'use' - not draining every river in the state, but rather allowing some of them to continue to be rivers. This is the so-called environmental use.)

When you bring up red herrings about poor people dying of thirst because rich techies are buying bottled water from nefarious companies stealing public water, you are being a patsy of BigAg.


Sure they can, it's just that in a healthy competitive market no one will buy what they're selling if they price themselves out. In an unhealthy market, however...


I think they are. The problem is that that price has no relation to the demand.

One concern is to stop monopoly water suppliers from overcharging. So prices have to only cover the costs of delivering the water.


> Inefficient use of water will disappear very quickly

Yeah, I'm sure that will have no public health consequences whatsoever.


What exactly are you dancing about here? Are you seriously trying to imply that people won't wash their hands because they're worried about the cost?

If the water-shortage is already so bad that it could cause prices like that for individuals, then you've already got a problem that'll cause health issues.


Water is subsidized because it is considered a human right.


The entities getting (implicitly) subsidized are giant agribusinesses, not poor people. In fact, in the article it says that the residents of San Diego are going to see $5-$7 a month increases for the next 30 years to pay for this desalination plant.

Having an annual statewide wholesale auction for water rights would decrease the cost to urban end users, not increase them. But some people are so reflexively opposed to market based solutions that they attack them even when the net result is improvement for the very people they claim to care about.


By saying people are reflexively against market solutions you're assuming they have not put any thought into this. I don't think it is that simple.


Yes... and? Subsidizing water for individuals who need to drink and wash? Sure, I can get behind that.

However, that's totally different than granting similar rights and subsidies to acres of cash-crops and chemical-refineries!


I assume it is more complex than appears on the surface. Which crops and processes deserve access to cheaper water? How much water will that save? How much will the price of goods go up as a result? What customers will stop buying as a result? How will farmers react? Should the government try not to bite the hand that feeds its people?

I haven't read any farm bills or anything about water data but that's what I would do first if I wanted to understand more.


> Which crops and processes deserve access to cheaper water?

If you're the one trying to champion "water as a human right", then I think it's only fair to ask you where you would draw the lines. What demarcates personal use and commercial use? How many gallons can someone use for their outdoor "washing" pool before you step in and say that they're abusing the system?

> How much will the price of goods go up as a result?

I don't know, but we have a distributed algorithm for solving it called "capitalism". Like any algorithm, garbage-in makes for garbage-out, and tuning it is a major pain the ass. One of the important inputs is whatever cost on shared-resources (or externalities) imposed by the government.


Yeah, I do not disagree. I think water regulation should be an open topic. Share data and hold public forums so more parties can work towards a reasonable system that is fair to both businesses and people.


Economic calculation problem


Can't we find something a little more natural like capturing more rain water before it goes into the ocean?

Edit: there's plenty of rain water.

http://www.forbes.com/sites/ashoka/2015/04/15/why-does-calif...


That and cheaper too.

http://www.notechmagazine.com/2015/06/water-johads-a-low-tec...

LA has a drainage system that tries to get water out to the sea as fast as possible.

If the water is not hanging around, its not going to evaporate. So no clouds to be blown inland. Evaporating water takes energy, which lowers ambient temperature, etc.

Johads are dirt cheap, simple and effective. The basic premise is you put in half moon banks every n 100 meters. The idea is that it keeps back a certain amount of water. Excess water overflows into the same channels as before, so there is no risk of flooding.

Failing that, solar stills are much cheaper than reverse-osmosis to build, and in south California with loads of sun cheap and effective.

However you still have to transport the water.


How do you deal with mosquitos?


We deploy spiders


That's what we normally do. The failure case we have encountered, however, is sometimes there isn't any rain.


There's lots of rainwater in aggregate if you look at very large areas, but I'm not sure if collecting rainwater over a huge area is necessarily more practical than desalination. I honestly haven't studied the matter, but judging from the fact that this guy's credentials seem to amount to "Has planted a bunch of trees," I'm unsure how much of an expert he is either. He says it isn't being pushed because there isn't any industry behind it, but that seems to be begging the question. Why is no one taking this field by storm if it's actually a more practical solution? Why isn't he making money hand over fist doing this? The disconnect between the reality he suggests and the reality we observe makes me doubtful about whether this is actually a more realistic approach than desal.


Wow, you opened a lot of boxes. Lipkis is actually much more than a guy that planted a bunch of trees. His organization, and a couple of others like FOLAR (https://folar.org), have been changing the way the city of LA approaches storm water.

As a nearby comment mentions, building regulations had been designed to convey rain water to the sea as fast as possible, due to a justified fear of floods. At the micro level, this means diverting rain water to concrete channels (e.g., streets or drainage channels). For instance, when I put in a building in my back yard, I had to install a pump to pump the water from a tank filled by the rooftop gutter into the street, rather than letting it soak in to my yard.

Now, multiply that by millions, and you can see we're wasting a lot of water.

Changing the whole conception of storm water ("collect and dispose of" -> "disperse and soak in") involves changing building codes and city/county/state infrastructure practices.

Because ground water is all externalities, there is no ready market solution.


Why is no one taking this field by storm if it's actually a more practical solution?

Because there isn't as much money in it as in ginormous megaprojects? E.g. the "train to nowhere"[1] in California had the support of a Teamster leader because:

   The legislators in Sacramento got it right
   when they voted to fund this project since
   it will help hundreds of people find good
   union jobs
and his quote continues

   and the high speed rail line will provide
   a viable alternative to car and plane travel
   in the state.
I don't think that HSR from Madera California to Bakersfield California will be a "viable alternative" to anything.

Follow the money.[2]:

   a catchphrase ... which suggests a money trail
   or corruption scheme within high (often
   political) office.
Same with water. Too many dollars at stake, and too many special interests, for simple commonsense solutions to be "practical".

[1] http://www.laweekly.com/news/california-bullet-train-to-nowh... [2] https://en.wikipedia.org/wiki/Follow_the_money


Well, my understanding is that in California, at least, environmentalists have blocked the creation of aqueducts/lakes for the past few decades.


I think that's called a river. And it's running dry.


Our HOA has a rule against collecting rain water. I remember a man in Oregon a few years ago got jail time for refusing to remove his rainwater bins.


I'm guessing there's a reason and possibly even a good one. Care to take a crack at it?


Step 1 should be upgrading water treatment facilities into water recycling facilities.


I recently read about a project in the Hudson Valley, where United Water would use desalination to draw water from the Hudson river.

Most of the negatives / cons I have heard before (impact on wildlife, where to discharge brine, energy, etc) ... but one thing stood out:

"Haverstraw Bay is polluted with contaminated sediments, sewage and urban runoff, and the plant’s intakes would be approximately 3.5-miles from Entergy’s Indian Point nuclear power plant, which releases radionuclides to the Hudson."

I guess many people are concerned that (1) the technology to remove these pollutants either does not exist, or is very expensive and (2) being a privatized water company, it may put profits over water quality.

My question then, is what kinds of things are in sea water that should ideally be removed beside salt? What is more contaminated source.. sea water, or water from land based sources?


I was curious how much radionuclides are in the water. Apparently, "nuclear plants typically release between a few curies and one thousand curies per year of tritium in liquid effluents; releases of mixed fission and activation products are much smaller (in the range from 0.001 to 0.01 curies per year)."[1] For comparison, it seems a glowing tritium keyring contains 0.4 curies.[2] One thousand curies would be 0.104 grams of tritium.

Also, there is an online database for this! [3] E.g., if I read it correctly, in 2008, Indian Point 1,2 released 0.09 Ci of liquid effluvents. (No tritium in the table?)

[1] http://www.ncbi.nlm.nih.gov/books/NBK201991/ [2] http://depletedcranium.com/my-attempt-to-import-tritium-key-... [3] http://www.reirs.com/effluent/EDB_Main.asp?l=n


Just as aside, I've dealt with quite a few utilities and United Water is by far the best among them. They are an excellent company.


That's just crazy. Rewind 130 years and you find a handful of reservoirs, some tunnels and viaducts, and gravity. That's all you need to provide some of the country's finest drinking water to 8 million people. https://en.wikipedia.org/wiki/New_york_city_water_supply

People were smarter then, because the technology didn't exist for them to be so stupid.


I've always wondered why desalination is so hard. From a thermodynamics perspective, dissolving salt into water isn't particularly enthalpic (the water doesn't get warmer when you do it), so it's never been clear what the fundamental challenges to reversing that dissolution are.

It's surprising there isn't some chemical reaction to precipitate out the sodium and chloride atoms bonded to something else, or whatever.


It's almost impossible to use a chemical reaction to precipitate sodium and chloride. Almost all their compounds are soluble in water. [1]

The easier way to precipitate chloride is using silver, you mix the salted water with silver nitrate and the silver chloride goes to the bottom. But you now have a sodium nitrate solution. (It's safe to do this experiment at home, if you are careful and follow minimal laboratory safetely procedures. But don't drink the water!) https://en.wikipedia.org/wiki/Silver_chloride#Chemistry

Just assume that all the sodium salts are soluble. The only example that I remember is the sodium uranil acetate salt. But it's definitely not a good idea to drink that water later. https://en.wikipedia.org/wiki/Uranyl_acetate#Safety

[1] I think that this is the main reasons why most of the salt in the sea is sodium chloride. Related question: Why doesn't the sea have too much potassium?


There are [multiple desalination methods](https://en.wikipedia.org/wiki/Desalination). My favourite is [reverse osmosis](https://en.wikipedia.org/wiki/Reverse_osmosis), though it does cost about $1.2 per cubic meter of water.

To answer your question, ion exchangers do what you ask, using sulfuric acid and sodium hydroxide, and produce a ton of sodium sulfate in the resulting desalinated water.


From a thermodynamic perspective, un-mixing two mixed things always requires energy.


From a first-law standpoint, how can it fundamentally require more energy than is released by mixing them?


The alkali ions are all inherently very soluble. Sodium chloride has a solubility of ~6 mol/L (and most other sodium compounds are in the same range of solubility), whereas an insoluble compound like copper chloride is more like ~6·10¯⁴ mol/L.


I always assumed the big question was "where do you put the brine"? (forget the name of the by-product of desalination) Do you dump it back into the sea? I don't actually know.


Electrolysis is a rather energy-intensive desalinization method.


Whatever happened to the idea of tugging broken off icebergs as source of freshwater. It could lessen the impact on rising seas, to some extent. Desalting of course would lessen it too. perhaps neither would be enough to counteract the overall melting. But both can address droughts.


> It could lessen the impact on rising seas, to some extent

And where do you think that water goes, after it has been put on the fields?


Ice bergs are nearly neutral as far as water level goes, since they displace about the volume of water they contain (if melted). If all the sea ice melts, the sea will rise on the order of mm. (I have the calculations around somewhere if you want details.) The problem is the ice currently located on land.


Even in it has an almost neutral effect, it still doesn't lessen the effect of rising seas.


When did desalination become cheaper? Saudi Arabia can be afford it because of the petro money but how about United States and reading the env. impacts not sure which way to look for water.



This is one of the reasons I'm hoping fusion gets off the ground fast. Oceans + Lots of power is a decent recipe for fixing humanities fresh water problem.




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