Water (in the form of ice) is quite common in the outer solar system. Water shortages in the present/near future are more about clean water.

Why would we run out of water?

I can see having massive shortages of fresh water, but that can be easily fixed with money and power.

I’m sorry that’s my bad I meant in a purely hypothetical manner, earlier today I read a passage from a friend of mines book and it mentions some alien civilization running out of water, and I couldn’t justify going to war over something so relatively “common” as in the components to make water are

We can't really run out of water...75% of the Earth's surface is water.

I don't know how true the Blue Gold documentary is, but they estimate we'll run out of fresh water in about 50 years as population grows and more water is needed.

Yes it is relatively uncomplicated to make water in a lab setting. I suppose it would be a matter of how much energy you could muster to create enough hydrogen to produce enough water to sustain a civilization. Of course once the water is created there are plenty of ways to recycle it.

But more practically, if we were to truly run out of water, we’re all screwed. The air we breath is laden with water vapor. Without it, it would be quite inhospitable. If we ran out of water, animals, plants and crops would desiccate and die faster than we could create water. Bacteria and microscopic life that is the underpinning of our entire planet’s ecosystem would rapidly dry up and perish. There’s no way we could produce enough to rehydrate the entire planet before life totally collapses.

We can't run out of water. You can make fresh water from sea water. There is zero chance we run out of water.

Not many places do this now because it's expensive but if we don't have a choice it will be done. It's still far cheaper than doing anything in space.

There is a ton of water just under the crust of earth. I think we we would dig for that first.

[removed]

When I was a kid, I thought we'd be drinking and irrigating with desalinated ocean water by now. Maybe no one has figured out the best way to profit from it yet although I understand that Isreal has been using desalinated water for a couple of decades.

It does have some dangers to it but if aliens are intelligent enough to travel to other stars to steal water they could probably make it

Thank you for the thorough answer and some how understanding my stray and incomplete thought, I really appreciate you

This is true in general. There are a few places around the world that are approaching day zero of water supply. It’s a solvable problem but needs more focus

I’ve been reading the expanse series and I’m a water treatment operator. This has raised my eyebrows a bit. If you’re talking about something like space station or asteroid located bases, the loss would occur through “gas-off” in a way. Gas-off is what we refer to as certain compounds going volatile and dissipating. You might be looking at something along the lines of steam escaping from somewhere. Rocket scientists probably have a different term.

Water should be nearly infinitely recyclable. But clean water? That’s the challenge.

Y’all can look up the Sparta Reuse Facility in West Monroe Louisiana. I used to work for the city, albeit on the other end of the water system producing fresh water. The SRF takes raw sewage, run off, storm water, all the dirty stuff, and processes it into clean water used in local industry. It is “potable”. Tastes like crap, but you can drink it. The point behind the project was to take some of the burden off the Sparta Aquifer here in Louisiana, and it’s done a phenomenal job.

Water is incredibly common in the universe and easy to make from other oxygen and hydrogen containing compounds. Comets are essentially giant snowballs.

Which leads to a huge gripe of mine with the first episode of Voyager. How could advanced space fairing civilizations have been at odds over not having water???

Something that occurred to me is that usually we create hydrogen from … water. You can do it by different methods, electrolysis being a common one. So I’m afraid we might run into a hydrogen problem before we even get very far along.

Could we just “collect” it for the galaxy

So I’m an engineer for a cruise line that uses desalination from Reverse Osmosis, the issue with doing it on a massive scale is the amount of brine waste it produces. It’s extremely concentrated brine (nasty salt water sludge byproducts). We would have to figure out how to dispose of huge quantities without damaging the ecosystems.

I do have another question, why is it so difficult to clean water

It would take less energy to re-hydrate a entire planet than it would to go to another star and pick up the water there and bring it back, especially if you do it in a reasonable amount of time. So yes a lot of alien invasion sci-fi is just dumb.

Thank you very much my good man

Desalination requires a ton of energy and money. As is with everything else on the planet, governments won't move until it hits the fan. We live in a world of over consumption of resources. I agree there is plenty of sea water in the world, and with the icecaps melting, it's a good idea to take as much of it as we can to make it into drinkable water to just maybe keep the oceans from rising. But from the stand point of 2022, we will run out of fresh water if nothing changes. They've known about this impending issue for almost a decade now and not much has been done about it. I wish it weren't so, but it is what it is.

Also the global population is expected to peak in the next century and then start a steady decline, possibly as soon as 2064.

I agree. When I was very little, I use to naively think that we can just ship snow from the poles for water. Like sending trash on a rocket to the sun. Or packing some sunshine into a box and ship it to a cold place, or vice versa.

Humans are great at solving problems. It's getting them done is the difficult part. Or sometimes, getting people to listen to start with.

Our usual solution to clean anything is to dilute it. IE add more water to it so the parts per million of the dirty thing drops. If you're trying to do anything else the processes are a LOT more energy/resource intensive.

Wow, great thought! Lots to think about.

I believe there are nebula made of water vapor, (or ice crystals?) that are more massive than our solar system, so we wouldn't even have to isolate the hydrogen and oxygen, but a controlled burn of H and 2O would be a source of heat energy. (Also a risk of explosion!)

Hauling around enough to make a difference for a planet, (either water or the gasses,) would be another challenge. Even if we had spaceships the size of a football stadium, that would be insignificant compared to one of the great lakes, much less an ocean. If we could haul around volumes comparable to large asteroids or small moons, then we're making progress.

Without doing any math, I am picturing spheres of water the size of Texas. It would take a steady supply of them to fill the world's oceans. Thousands? IDK

So it’s like pouring 100 gallons of fresh water into 1 gallon of salt water

Wow. Did they speculate how the decline will happen? People having less babies?

Water for agriculture is what we need to worry about

In corny sci-fi terms would this be easier then invading a planet

Eyup. You could probably drink the resulting mix but increasing your supply of drinkable water by 1% isn't much of a solution. Literally.

The current cheapest way to make hydrogen is I believe from steam reforming methane.

[removed]

Likely we would end up with entire lakes of "dead" water that would be a future problem.

Just as a counterpoint, we will not have any water sometime after 100 million years to 1 billion years. (I've seen a lot of different estimates, which seem to keep getting revised to shorter and shorter times.) Of course we'll have a bigger problem long before that as at that point the surface will be hot enough to boil the water away, which is way beyond what we can survive.

This kinda demonstrates part of the issue with plans to colonize Mars or other planets. People look at mars with no ionosphere an atmosphere so thin it's basically a vacuum for all biological purposes and say "yeah, but it has land".

Yeah there's plenty of everything in space, but we're not running out of anything on earth, we're just polluting it. And it'll almost always be easier and cheaper to clean and use contaminated seawater for literally anything than it will be to drag heavy ass water from the outer planets or asteroid belt all the way back to earth.

Can’t we just get light ass water instead?

What about lasers?

Correct. Much less expensive than electrolysis.

I concur. I used to erroneously believe that we could just carry snow from the poles for water when I was very little. like firing trash into space on a rocket. or placing some sunshine in a package and shipping it to an area that is freezing, or the opposite. People are excellent problem solvers. The challenging part is finishing them. or, on occasion, starting by persuading others to listen.

There’s a pretty natural curve as societies become educated and more industrialized, you see infant mortality plummet and overall birth rate drop (there’s a collection of different causal reasons for the drop in birth rate). Negative percentages for a while, then (we assume) stable within a margin of error year over year.

What this means is that we should see various societies level off or decline a little before stabilizing. The only area that really looks at the flattening of population growth as a desperate problem is modern capitalist economies, where you need an ever increasing supply of cheap labor to continue pushing the holy line upwards. A differently structured economy would likely not care much about a stable or stably decreasing world population.

[removed]

Exactly. Basically as countries develop and get more educated people tend to have less babies. According to Wikipedia 48% of countries already have under a replacement birth rate including all of the European Union. Empty Planet by Darrell Bricker discusses the phenomenon.

We’re going to run out of clean water a lot sooner than 1000 years lmao

Much easier! No one is fighting for the water, and it doesn't have to be lifted up from a planet. Why fight a war for the privilege of lifting all that mass out of a gravity well when you can hoover it up and fly away?

Also, when I said the nebula were more massive than the entire solar system, I couldn't remember if it was hundreds of times more, or thousands, or millions. I just remembered it being astronomically more than the amount of water on earth.

[removed]

It's not a matter of running out but a matter of the cost to "clean" septic water.

It would be quite the trick to drain the oceans of all the water they contain in 1000 years. Please refer to this:

https://i.redd.it/7t81ljatuh8a1.jpg

Please repeat this, clapping your hands together with each word

We. Are. Not. Going. To. Run. Out. Of. Water. On. Earth.

However, FRESH WATER... that's a tricky one.

The most brute force way would be desalination, of which there are a few ways to do this (evaporative, osmotic, etc). All can be resource or energy expensive (evaporative can be done with either a huge solar still, if you have a handy desert climate, or by using energy to boil salt water and then allow fresh water to condense)

Both have the problem of what to do with the highly concentrated brine (if you don't mind killing local fish/destroying your local fishery, sure just dump it back into the ocean).

But lets say that, yes, somehow we have squandered 321,003,271 cubic miles of ocean, and we need water from somewhere else. The outer solar system is _loaded_ with water ice. Often in combination with Nitrogen, Carbon Dioxide/Monoxide, Cyanide (HCN), and other hydrocarbons in smaller amounts. Just bring a few comets in to the vicinity of Earth and that material could be mined. Just don't let the comets _hit_ the Earth--you will make no friends that way, no matter how thirsty they are.

We won’t be able to clean sewage water way sooner than 1000 years. Cleaning sewage water requires infrastructure, infrastructure which as I see it, will be gone a lot sooner than 1000 years.

Maybe just no ass in my water?

Potable water is the issue when it comes to humans. Spring water is needed to grow planaria, so that's what I got my cat in the city.

Where I live (Perth, Australia) we ran out of available fresh water 15 years ago. Now about half of our water comes from desalination powered by a wind farm.

https://www.watercorporation.com.au/Our-water/Desalination

It’s about scale and expense more than anything. The more you need to clean, the more difficult and expensive it is. The source quality will make a difference too. I treat mostly ground water, it’s about the easiest and cheapest. Most expensive part is the electricity to run the pumps. Then there’s desalinization, reverse osmosis, surface water treatment too.

[removed]

Not a bad thought. Hydrogen is the most abundant element in the universe and there better be oxygen around or you don’t need water. Just need to burn the hydrogen, combustion products of burning hydrogen are water and energy.

The hard part would be getting the hydrogen. Then compressing it. Out of reach for the people in the Mad Max world but if you’re in space I’m sure you have a compressor laying around. Just need to event Bussard collectors to harvest the hydrogen.

Dump it in the Dead Sea. There's nothing living there anyway.

Solar powered Desalination of Sea Water is a well proven technology done in the Gulf states, especially Saudi Arabia. Additionally many minerals & metals are acquired during the desalination process.

Dont criticize my childhood!

[removed]

[deleted]

[removed]

In reality, the world will not run out of fresh water. However, we may run out of usable water or see a drop to extremely low reserves. More water is required to sustain industries, households, and the environment as populations grow.

Aside from that, climate change has an impact on the amount of usable water we can collect, as well as the processes involved in cleaning that water for use.

However, if what you said occurs and we run out of portable water, we will definitely not use the laboratory method. It is somewhat expensive and can not be produced efficiently on a large scale.

We may need to take a more advanced approach than Israel did.

Israel’s history with water is long and distinguished. As a nation that is comprised of 60 percent desert, water technology has been at the forefront of Israel’s innovation sector.

The country now draws and desalinates 75 percent of its drinking water from the Mediterranean Sea xD.

You’re talking about gravitational tractor lasers? Yeah nah, we a few hundred years away from that if we are lucky.

[removed]

We’ll spend billions on a keystone pipeline for oil. Why can’t we do that for water. Canada and Great Lakes water literally pouring into the ocean and drought stricken states just screwed.

the kaizon are basically a scavenger species, they weren't actually advanced technologically, they had just stolen some space ships

[removed]

I was wondering where the concentrated seawater goes. I guess that could offset the fresh water coming from the melting glaciers. Very interesting. Is desalinated water considered fresh water, or processed water?

"Seawater desalination is four times more energy intensive than groundwater collection and over 40 times more energy intensive than water sourced from dams."

And all that energy has to come from somewhere. The website doesn't say, but does each plant have its own wind farm?

That’s so awesome

I really enjoyed the tour of this water treatment plant in SF. It doesn’t make potable water, but the effluent looked quite nice compared to what was coming in! Stuff filtered out does get composted, so it’s still producing something useful

My (least?) favorite part though was this image with terrible implications. We’re in this huge room with big pools of sewage where they’re letting solids settle to the bottom and oils to the top. And mounted on the walls are a bunch of life preservers.

The thought still makes me shudder

We can filter water to get all the toxins and impurity’s out. Salt water is the difficult one, to convert to fresh water.

[removed]

I far prefer to have no water in my ass

For what it is worth, water is a byproduct of burning hydrogen. Water reclamation is already a thing and by the time we are in space we will have water reclamation in-built. Capture of ice rich objects will certainly be normal in a space faring culture.

We can just dehydrate it, then it will be lighter and not cost as much to move😜

Seeing as how the comments already went stupid, I’m just going to say BRAWNDO

It’s has what plants crave

There's lots of hydrogen in space but it's spread so thin it's basically non-existent. On the other hand, every year we collectively emit 41 billion tonnes of water made from hydrogen that has been locked away in hydrocarbons. Also CO2 which is the part we're usually concerned about.

[removed]

I will never understand why people think we're ever going to run out of water on this planet. Over 70% of the surface is covered in it, and basic chemistry will tell you that when O2 and 4H are present, they will combine into water. So unless we're somehow consistently splitting hydrogen and oxygen atoms for several billion years, or are otherwise removing water, oxygen, and hydrogen from the planet, we will never run out of water.

Clean, drinkable water, on the other hand, is harder to come by, and for some reason, companies have decided desalination plants and other purification systems are just not worth investing in to provide clean drinking water for millions of people around the globe. Something about "what's in it for me," I think they said.

Wait.. you like sex? And money?

We should hang out

[removed]

Put content in the title. "question" is not content.

And how would we "run out of water"? What does that even mean? Where did it go?

We could just make it from stuff on earth. Combustion creates water.

I mean truly running out of water is going to be very hard with the ocean sitting right there. We can desalinate water now. It’s just more expensive than pretty much every other way of getting it. The only thing more expensive would be gathering hydrogen from space and combining it with oxygen.

Also water doesn’t disappear. The water cycle recycles it. It all pretty much eventually hits the ocean. It isn’t getting ‘used up’, just getting less accessible.

There is a classic science fiction novella by Isaac Asimov that kind of addresses this - spoilers ahead. Earth is concerned about the amount of water they are sending to support Mars colonists. Mars sends rockets and redirects a mostly ice moon to Earth, and says FU. !artisan Way

Naw, I saw a documentary on this topic in the 90s. Swat Katz: The Radical Squadron s2ep03.

Totally happened.

[removed]

[removed]

[removed]

I'm kinda glad I'm not the only person in the world who remembers that.

Any science fiction where they can exploit a solar system and it talks about resources shortage, is generally idiotic. There is so much mass in the solor system, that its defacto infinite. Including water.

Wouldn't you also run into issues introducing a large amount of extra water to our ecosystem if we haul it back from the outer system? Water is infinitely recycled so adding more would change the weather, increase sea levels, etc.

Hello u/Psychological_Wheel2, your submission "Question" has been removed from r/space because:

• Such questions should be asked in the "All space questions" thread stickied at the top of the sub.

Please read the rules in the sidebar and check r/space for duplicate submissions before posting. If you have any questions about this removal please message the r/space moderators. Thank you.

[removed]

I would love to hear someone who understands this to expound on it.. fascinating.

Cost of transportation and emissions from the vehicles to get it there would be massive.

Indeed. On top of that, clean water is not that hard to come by with enough energy.

Clean energy is and will be the underlying bottleneck (and no, fusion won't be the answer to that for many more decades; we'll have to solve this long before then).

The amount of energy required to cause changes that weren't very localized would be so high that you could probably fix any impacts for half as much energy

You can’t swim in aerated water and I’m sure there was aeration in progress nearby. The solids and FOG (fats, oils, and grease) present their own hazards too. I’ve been dunked a time or three myself. To say it’s unpleasant is an understatement. I fell into a wet well once, and as if bouncing off an iron pipe and smacking the surface of the grease cap weren’t bad enough, getting back up through the grease cap with two broken ribs, a concussion and the resulting disorientation were even worse. That day I decided that fall harnesses were my best friend. Sometimes a grease cap can be thick enough to walk on.

The plant that I run now produces potable quality water. It’s considered non potable because of the source and because the quality simply isn’t as reliable as something like the Sparta facility or whatever system they’d be using in SF. I’m running a low tech system that only processes a few hundred gallons per day. With a bad weather upset I could end up discharging some pretty gross stuff, then I have to get the health department involved, environmental impact studies, get in some trouble, get fines levied against my company and it could have a big negative impact on nearby communities if it goes uncorrected. For obvious reasons, I try to avoid that. My old plant processed 3 million GPD, and I think the Sparta plant is designed for a 10 million GPD max capacity and I don’t believe it’s ever had to run at max capacity. It was built with the prospect of expansion in population. Large plants are MUCH more labor and energy intensive, but also more reliable. In very simple terms, the much larger volume acts as a bit of a shock absorber when something happens. Like if some jerk decides to dump a bucket of bleach or car wash soap in one of my manholes, I’ll have to take my plant offline, have it pumped out, go get some activated sludge from a friend at another plant and start from scratch. If that happened at the Sparta, they wouldn’t even notice it.

But the whole point here is, water is recyclable, especially if we make sure our waste is “clean”, as in chemical free, trash free. Only thing that should ever go down a sewer line besides water, is the four P’s: poop, pee, puke and paper. In a closed system such as maybe a space station, the biggest obstacle I’d see right away is the equipment. You’d need a way to dewater and disinfect the waste. I’d personally advocate a dewatering press and UV system, but doing that in zero or micro G would require some extensive modifications. The most economical way with the tech we have now is to resupply fresh water and vent the waste. Someone else mentioned there’s plenty of ice floating around out there. I wonder how space ice would taste?