*typical American household uses directly.

Don't forget food, industrial, etc

Freshwater withdrawals per capita in the US (which includes agricultural exports and animal feed such as alfalfa sent to Saudi Arabia) are around 1550 cubic meters per year.

https://ourworldindata.org/grapher/water-withdrawals-per-cap...

So that is around $775 per person per year assuming no net change in water use. In contrast, Germany uses around 410 m^3, France around 475 m^3, and Australia around 724 m^3, so the US is a significant outlier.

That equates to around 4,000 liters per person per day.

Freshwater withdrawals is a very broad category, it also includes water released to turn hydropower turbines. But it's also unfair to compare across countries without taking into account water sent between countries in the form of produce and products.

You were quibbling about how 1,000 liters per day does not adequately account for all usage. Freshwater withdrawals is on average going to be a overestimate and the US is one of the worst outliers with significant agricultural exports which are one of the largest contributors to differential water withdrawals. Despite this, it would only be $2.00 per day for a fully desalinated water supply even if we safely overestimate usage. Despite it being 4x higher than the person you replied to said, that is still incredibly cheap.

I agree with everything you say (with the assumption the person I replied to has the correct price, which I know nothing about)

>Despite it being 4x higher than the person you replied to said

$0.5 was per household. $2.00 was per capita. So 10x higher.

4,000 liters per day is too much. It is 10 full bathtubs. Do Americans leave the tap open or do they take a bath 10 times per day?

Agriculture and industry can use _a lot_ of water. Likely the 4000l figure includes that.

It accounts for the water used in agriculture, industry, power generation, etc. Those uses completely dominate domestic water usage including for aesthetic purposes such as lawns and golf courses (e.g. around 80% of water usage in California is for agriculture and power generation if I remember correctly with only around 5-10% for all domestic usage).

As you will note, the average German consumes 1,000 liters per day by the same metric which is 2.5 baths per day which is obviously unreasonable if we were only considering direct domestic water consumption.

To be fair, the agriculture is being grown to feed people, so it is fair to include the consumed produce in each person’s water footprint. This is further exacerbated by growing animal feed for animals that are consumed which is even more “water inefficient”. The US is a major food exporter, so it is over-represented in these sorts of numbers, but it is a fair approximation to within a factor of maybe 2-3x of the embodied water consumption of the average American.

Maybe my comment wasn't clear. That figure isn't great - we just divided the total amount of freshwater diverted to some kind of use by the population. That even includes letting water flow past hydropower turbines. It's obviously too big.

But not counting the water used to put food on your table is too small. So this establishes some bounds.

> 1550 cubic meters per year

This is an interesting number. Recently, I saw complaints that green hydrogen is impractical because it would use too much water. But if all the per capita energy use in the US went to electrolysis, it would use about 1% of this water per capita (and, of course, green hydrogen would be only a fraction of total energy use, due to all the preferred direct uses of electrical energy.)

When you burn the hydrogen you get pure water back too.

That just goes to show that people will complain about anything instead of applying their brain.

There are plenty of valid objections to hydrogen as a fuel, but water use is a total non issue. Not only does it use so little, but when you get energy back out of the hydrogen, the waste product is water again. It’s literally a renewable cycle.

Yes, but you pay for that when you purchase the products. These costs are baked in.

But we're talking about increasing the per-gallon cost of everything. So the baked in cost would increase.

Or moving water intensive operations away from areas where water is expensive. No one is going to be doing desalination in Michigan.

why not? we're growing heavy water using crops in places with little water. logic is not always the deciding factor if involved at all in a lot of modern things

There are a few very big salt mines below the great lakes. We could totally get a desalinization plant in Michigan by pulling water from the lakes, salt from the Detroit salt mine, and combining them in the input stream to the plant!

someone has been playing in the perpetual motion machine sandbox again i see

I think it sounds quite sensible. How is it different from using all fresh water as an all you can dump free-for-all public sewage system before wondering where the drink is coming from? In India they poop in the water then take a bath in it and cook their food in it. In the west we do our pooping upstream because it looks so much cleaner that way. NO! I fail to see how adding salt before desalination is any less sensible. Lets just do it.

you're desalinating water to have an abundant source of fresh water. why in the world does taking fresh water and adding salt being mined from the ground together to make salt water to then desalinate make any sort of sense?

We already have abundant fresh water. We use it to transport sewage, fertilizers and other crap to the ocean. It would be silly to try to clean it afterwards - but here we are?

Adding salt is a great idea, it pushes our collective stupidity to a noteworthy level of nonsensicalness.

It makes me wonder what other hard to remove poisons we could add to challenge ourselves. Perhaps design a new disease?

>We already have abundant fresh water.

Clearly, you're not having a rational conversation with comments like this. If there was an abundance of fresh water, the western half of the US would not have been in severe drought conditions for the past however many years. This is where I leave you as you are just making things up like and not even having a good faith conversation

I'm just watering the lawn.

Certain Michigan towns may need to do so...

I think the implication is that the costs will be higher than 50 cents if 50 cents does not cover non-household use.

Good point, though brings one to another interesting detail from the Israeli water book:

Over 90% of sewage water is treated and recycled to use as agricultural water, creating kind of a full loop here. Very impressive infrastructure.

Agreed. Desalinization is cheap. It works just fine for providing water for coastal people. As California is proving.

What it does not do is provide freshwater for argibusinesses. As California is also proving in the Central Valley. :(

There are no water pipes from the coast to the central valley?

I wonder if NIMBYism blocked that?

And if an agency wanted to transport water like the USA national oil pipeline system, would they be blocked similarly?

There are aqueducts between the CV and coastal areas. The water goes the other direction.

If desalination becomes widespread, I imagine the water not shipped to the coast could remain in the Central Valley. I don’t know one way or another if this would make political or economic sense.

EDIT: Wikipedia has a good overview: https://en.m.wikipedia.org/wiki/Water_in_California

Water rights are so complicated that they’d probably sell the water to the Central Valley before it ships to them. I think it very unlikely that they’d give them up.

There's no way the water would be affordable for agriculture if it had to pay for pumping it uphill/inland. There's a reason the rivers flow in the other direction.

From my (limited) understanding of agribusiness, particularly in California, it will be hard to be cost competitive with current water sources moving forward as they are heavily subsidized (read: near-zero costs).

The upfront cost from my understanding is in drilling a deep well. Those wells keep getting deeper and costing more. But, past that, it's just the cost of running the pumps to drain the underground aquifers. IIUC the cost of water is free plus the cost of harvesting it from the commons.

I might be wrong here, but all the billboards that say "is growing food wasting water?" along the interstates in California don't really matter over long time horizons. They're advocating for draining the water tables. You can't do that forever. Doesn't matter if it was a "waste" or not, it'll be gone soon and they'll have to pay to pull water from somewhere else or stop growing crops there (or the state will pay to give them water).

When "free" water runs out, other water sources will suddenly be cost effective. But it's hard to compete with free.

Pumping is at cost to them, but irrigating they pay a whole $20 per acre foot from our local water district. The wells are used when they want more than allotted.

Many of these canals are quite old and while they do require some maintenance, the upfront costs of the dams, reservoirs , and canals are largely paid off. Those maintenance costs and any upgrades are paid by the district customers.

To be fair to the author, difficult here could just mean “more complex than it seems” which he does a good job of illustrating, specifically around the additional concerns that go in beyond the actual processing of the water.

He says it’s viable for many applications.

That's not too bad. the normal baseline consumer costs are actually more expensive than that. normal base use in irvine ca is 1.78 per 748 gallons which is almost 3000 liters. (2831.488 liters)

I assume that's cost to make and not total cost to consumer post treatment plant distribution and maintenance so it would be more expensive than that but still in the ballpark of reasonable.

> That's about the same amount of water as a typical American household uses per day.

I assume you meant per year?

No, 1000L/day is about right for a typical American household. [1] claims "The average American family uses more than 300 gallons of water per day at home." 300 gal is 1136 L.

https://www.epa.gov/watersense/how-we-use-water

I know American toilets are comically big but 250L a day on flushing them seems insane to me. A cursory google suggests the average UK household uses 350L a day in total!

That's like 20 flushes. It's a lot more than I'd expect for "typical". Maybe a family of 5 does 20 flushes. Or maybe it's 2 people with strict anti-if-it's-yellow policy.

Cheap for Westerners.

As I understand, before getting 50-cent water you need to pay a billion dollars upfront. Why so expensive?

The biggest plant in the US, near San Diego (Carlsbad), cost $1B to build and produces 200,000 m^3 per day. Israel's biggest desalination plant, Sorek, cost $400MM and produces over 600,000 m^3 per day, so 40% the cost and 300% the water. So I assume a large part of the cost of the Carlsbad plant is just all the usual reasons everything is insanely expensive to build in California.

https://en.wikipedia.org/wiki/Claude_%22Bud%22_Lewis_Carlsba...

https://www.water-technology.net/projects/sorek-desalination...

The Carlsbad plant is in Carlsbad, CA. If you look at the neighborhood it's in, the houses are 1,200-2,000 square feet and sell for $2-$5 million. Everything is expensive.

If we could make cheap small nuclear reactors I don’t think drinking water availability would even be a thing we talk about near coasts.

It seems as though many problems get solved once the cost of energy approaches 0.

Residential water use is nothing.

In California, where we have persistent water shortages, residential, commercial and industrial water use ( including all landscaping, golf courses, etc) all put together still only amount to 10-20% of overall water use, depending on rainfall

Is the only remaining use left agricultural?

Looks like on average the data shows 42% agricultural. https://water.ca.gov/Programs/California-Water-Plan/Water-Po...

No, you are being misled by “environmental water,” which is a fancy way to say it’s water we don’t use because were not allowed to. This doesn’t make any sense, how can you include water you don’t use in your accounting for water use?

The reason this is there is to downplay the outsized use in agriculture, and also to shift some blame to folks that voted not to allow this water to be used in the first place.

But still, if you want to cut spending and are looking for where your money is spent, you don’t include money you choose not to earn in your list of spending.

Letting it flow through the rivers and delta to the ocean is half of it.