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JFitchett92
11-24-2013, 10:02 PM
Hey all,

Just a quick one. In my novel's world the entire southern side of the planet is desert. These lands are still inhabited but it's towns are few and far apart. With water being thousands of miles away and very little precipitation, how could the people of this land get water?

The more realistic the better, but as it's a Sci-Fi novel fictional ideas are still welcome.

Thank you.

King Neptune
11-24-2013, 10:27 PM
One thing that usually works on Earth is distillation from the soil, because there usually is some underground water. Dig a good sized pit; take a sheet of plastic put it over the pit with a weight in the center to hold that down and centered; put a water container at the bottom of the pit, under the weight. Then wait. In most Earthly deserts there is a constant but small evaporation of water from underground sources that will condense on the plastic and drip into the container. In the Sahara this method is very useful, because there is a large aquifer under ground. I believe that the Kalahari and the Gobi are similarly endowed, but there may be deserts where this will not work.

Williebee
11-24-2013, 10:30 PM
Water from what plants there are, although that's tricky as some of it will be acidic and perhaps poisonous.

Siri Kirpal
11-24-2013, 10:32 PM
Sat Nam! (Literally "Truth Name"--a Sikh greeting)

Cactus and other plants. With caveats about spines and some poisons.

Blessings,

Siri Kirpal

Cath
11-24-2013, 10:41 PM
Towns are most likely to grow around water sources since it's an essential resource needed for growing food, supporting livestock, building, etc. Without a substantial supply of water, the population is more likely to be scattered, desert plants etc could only support one or two people, not a town's population. If water isn't coming from above, maybe there's an underground source? Even with a deep water table, the technology could exist to tap into deep water resources and pump them to the surface.

wendymarlowe
11-25-2013, 12:45 AM
I think you need to look to your geology and anthropology for this one. If there isn't any water source nearby for your towns, why do people live there? How do they grow plants for food? Do they have anything keeping them from just being nomadic? Is the region desert because it's hot (like the planet always has that side toward the sun or something), or is it actually fairly cool but just gets no rainfall? If no rainfall, why not? Are there mountains preventing the clouds from going that far inland, or is there just not that much water on the planet's surface?

I'm having a hard time coming up with a geologically plausible reason for half a planet to be desert and the other half not to be, so if you can answer that, you will probably find an answer to your water problem.

JFitchett92
11-25-2013, 02:05 AM
Thanks for all the responses.


Towns are most likely to grow around water sources since it's an essential resource needed for growing food, supporting livestock, building, etc. Without a substantial supply of water, the population is more likely to be scattered, desert plants etc could only support one or two people, not a town's population. If water isn't coming from above, maybe there's an underground source? Even with a deep water table, the technology could exist to tap into deep water resources and pump them to the surface.

This response was very helpful. I did some research into groundwater and deep water resources and as my story is set thousands of years in the future, it would be reasonable for there to be some sort of hi-tech pumping apparatus capable of tapping these sources. This was my draft idea, but I wanted to double check how plausible it would be.

Another quick question. In this universe people are able to produce food synthetically, so couldn't water be produced in a similar way? This would then give me two sources of water to play around with.

Many thanks!

Helix
11-25-2013, 02:51 AM
You might get some tips from looking at how Alice Springs in central Australia gets its water. The town, which has a population of about 25,000 people (plus tourists), relies on aquifers (http://www.lrm.nt.gov.au/water/wise/water), but that water has accumulated over thousands of years and the aquifers have a low recharge rate.

Your town will probably have good recycling facilities too. They wouldn't be chucking out water.

waylander
11-25-2013, 03:11 AM
Thanks for all the responses.

Another quick question. In this universe people are able to produce food synthetically, so couldn't water be produced in a similar way? This would then give me two sources of water to play around with.

Many thanks!

Produced synthetically from what? Hydrogen and Oxygen? If you have cheap bulk supplies of both then sure this is possible, but it is not exactly energy efficient. Condensation of hydrocarbon combustion products? Again possible if you have copious supplies of combustible material, but that strikes me as unlikely in a desert. Captured icy asteroids? Sure, if you have energy sources for moving them.
The thing you have most of in a hot desert is solar energy, so purification of salt/brackish water would seem an obvious choice, plus you have the energy to pump it over distances.

ULTRAGOTHA
11-25-2013, 05:10 AM
Read Dune. Several ideas for capturing water in those books. The sandtrout have the underground water sealed off so they're limited mostly to atmospheric water, reclaiming water from organics (plants, animals and people) and hauling from the ice caps.

Putputt
11-25-2013, 12:57 PM
Along with methods of capturing water that others have suggested, your town should also have a reliable water recycling method like Singapore's (http://en.wikipedia.org/wiki/NEWater).

boron
11-25-2013, 05:05 PM
There are articles and videos about how collect water from dew. Some .mil sites are quite practical.

Here's AquaMagic - an engine that produces water from the air (using wind...)
http://science.howstuffworks.com/environmental/earth/geophysics/manufacture-water1.htm

Here are some examples how long have people survived without water (http://www.ehealthstar.com/dehydration/how-long-can-you-survive-without-water) (for example, in a desert at 90 F, one may survive for 7 days).

NeuroFizz
11-25-2013, 05:22 PM
When water is scarce it will become a Black Market commodity...or someone will find a way to monopolize it's sale and distribution. In fact, this has been suggested by the CEO of Nestle, who thinks water shouldn't be a public right, but rather a foodstuff that is privatized and marketed just like any other food material. He thinks it should be owned by the rich and sold to everyone else. This should give some insight into what the situation would become in a freshwater-limited world.

Also, consider that in our world land is a relatively small proportion of the total area of the globe. If freshwater supplies were to "dry up," desalination would become a priority.

WeaselFire
11-25-2013, 05:42 PM
With water being thousands of miles away and very little precipitation, how could the people of this land get water?

Wells?

Really, how do people who live in deserts on Earth get water?

Jeff

NeuroFizz
11-26-2013, 01:07 AM
Wells?

Really, how do people who live in deserts on Earth get water?

Jeff

Phoenix - mostly from a series of reservoirs on higher ground
.
Tucson - from ground water and from a large cross-state canal (Central Arizona Project - from the Colorado River).

Fenika
11-26-2013, 01:56 AM
Keep in mind microclimes. For me, this was always well exhibited in the Caribbean. Drive around a tropical island, then go over a hill. Bam, desert, complete with cacti and shrubs.

So any mountains, even if dry rocks on the surface, will collect water/rain, and form rivers or at least washes (dry stream beds that flood with every rain). Damn off some of these areas, get some backup water sources or use water carefully, and you are set to go in the middle of the desert.

Brandon M Johnson
11-26-2013, 02:08 AM
As already mentioned, you need to read Dune immediately if you're planning on writing a sci-fi novel based in a desert. I think that might be a law in several states.

Getting water from deep underground seems plausible, but you need to explain why people live in the desert instead of the half of the planet that's presumably more habitable.

In a pinch, one of your characters can use a plant for water. Perhaps you'll have cacti or some weird alien plant growing sporadically. If you want to go a little graphic, maybe there's a creature of some sort that people on your planet kill and drink the blood of if they're desperate.

For normal circumstances, though, I'd stick to an advanced pumping system of some sort. Or maybe they can use some device that brings moisture out of the clouds, if you can find a way to make that make sense.

Good luck with your setting.

Torgo
11-26-2013, 02:09 AM
A lot of these questions are answered in DUNE, to be honest. Big condensation traps; clothing and habitats that retain moisture; strict water discipline, which implies increased cultural significance for water.

EDIT: Oh, multiply ninja'ed

redfalcon
11-26-2013, 02:40 AM
They used moister evaporators on Tatooine. If it's good enough for uncle Ben, it should be for you.