"Peak Water" and the US Southwest

Chris Hopkins

Tue Oct 23 05:45:10 -0700 2007

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A few of my daft ideas here - someone please find fault with them:

Find a desert you don't really care about and pump sea water onto it.
There are already lots of power plants that use sea water for cooling - well some/all of this water instead of pumping back into the sea, pump this water into a desert. Now This won't be directly usable by anyone, but it will cause lots more evaporation. More evaporation = more rain. Do this in the right location and you could/might be able to get more rainfall in the locations you want.
Now is this a bad idea because we are messing with things we don't understand*, a bad idea because we are messing with desert environment, or a good idea because it solves 2 problems at once?

My other mad idea is to move population centres onto deserts. Leave the river deltas and fertile farm land for just that purpose and use the deserts for things that don't need anything except square kilometers to build on.

Finally how can there be a shortage of fresh water when you have rivers like the Mississippi that have huge ammounts of unused fresh water. True, taking all that water and re-distributing it would bugger up the river ecology, but it would create new ones too. How can there be a fresh water shortage when there is all that there unused.
Now maybe piping it to where you want it to be used is a big undertaking, but the resource is there we're just not using it.

Criticisms anyone?

*But then we never understand things until we try them, would we have understood nukes if no-one built that pile on the tennis court?

"Peak Water" and the US Southwest

Thomas Lord

Tue Oct 23 09:07:07 -0700 2007

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Criticisms anyone?

First, you need to do some math to figure out how much water you're going to need to pump into the desert under even your most optimistic guesses about the impact on rain fall.   I doubt that it pencils out so we can spare ourselves criticizing the idea on environmental grounds.

Second, increasing rainfall in socal isn't going to help much.    Instead, you need to do things like add a couple of feet of snow to the Sierra-Nevada mountains or invoke magic to make the Colorado river three times larger.

Third, we already did move everyone in socal out to the desert (or near desert) -- to land that was fairly useless for much else (until it became irrigated with potable water).  It's called southern california.    It's Chinatown, Jake.

Fourth, you are right that people should not live in fertile floodplains or next to the ocean but below sea level, for the most part.  Duh.  If you're going into that battle here's your plan:  you'll need to kill federal and state subsidies and insurance that encourage development in these areas;  you'll need strict zoning to prohibit development;  you'll need to explain to countless small jurisdictions all around the country some other way that they can get a huge boost in property tax revenues;  you'll need to explain to a lot of land owners your theory of what compensation they get for what is essentially an emenant domain siezure.   So, you need to fight this much-needed battle on two fronts:  (a) Sure, try to prevent development there.   You can slow it but you'll never stop it.  (b)  Work the positive battle in a different way: by making it far more attractive to live elsewhere (e.g., work on making cities and close 'burbs nicer).

Fifth: the big winning pattern humans have found over 10K years or so is to, yes, farm the fertile lands but, no, not live in the desert.   Rather, surround the fertile lands, occupying all of the space that is buildable but inconvenient for farming.   People whose staple crops grow on mountain sides live in plains.  People who grow in plains live on mountain sides.   Given the choice, people generally don't build where the river floods, etc. though, traditionally, poor people often make due that way.   But, anyway, no, we don't need to high tail it to the desert (and think of the impact of the support infrastructure that would take) -- we only need to live "around" the farms.

Last: water doesn't work that way.    The Mississippi is not a bunch of "unused" water -- it's rather heavily used and controlled.   It's used for irrigation, shipping/transportation, drainage, and, yes, potable supply.   Pretty much every gallon of flow through that river is spoken for already.   If you try siphoning much off in a new way, upstream, thus reducing the flow downstream, you won't get very far.   It would probably take about a day from when you announce your intent to when the first law suit subpeonas and even emergency court orders are served.

And, the Mississippi is a reasonable illustration of the problem.   It's the same story all over and the big muddy is just one example:  all of the water supplies, more or less, are completely spoken for, stretched to the limit of their capacity, difficult to manage (in the civil engineering sense), polluted, and very vulnerable to climate change.  There's no good substitute on the horizon -- even star trekky magic like massive scale desalination pencils out to create as many environmental disasters as it solves.

So, here's your plan for that battle:

Start with conservation.   Low flow toilets and shower heads.   Eliminate most grass lawns.  (Recently, Las Vegas created an incentive program to help eliminate water-intensive lawns.   They announced it as a "Cash for Grass" program.   After some initial confusion and dissappointment for a large throng of drug dealers, the program was said to have been quite successful.)

Preservation and restoration:  Keep the damn watersheds and wet lands clean and undeveloped! (Dammit!)  Or ELSE!   Where they are already horked (most everywhere): CLEAN THEM UP!

Sustainability: Stop buying the products of industrial petro-farming and buy as much as you can from the zogger's of the world.    Food prices are going up anyway and the price of US labor is going down so -- now more than ever.

Sustainability: on a case by case basis, you need plans for each region.   It's 10,000 small, nasty, city, county, and state-level fights.

Your footnote:

Nukes:  we would have figured them out anyway.  Were it not for the war (and the social systems that generated it) we might have been a lot more leisurely about it and handled the new knowledge more safely.


-t

p.s.: Nice post!   Sorry to shred your ideas a bit but I liked reading about them anyway!

"Peak Water" and the US Southwest

Charles E Hill

Tue Oct 23 11:43:00 -0700 2007

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Sounds better than my idea.  I was thinking set up one honking big desalinization plant on the Pacific coast, then run one monster pipeline up to the headwaters of the Colorado River and start pumping.  Refresh the river from the beginning.

It would probably need its own nuke plant to be able to push that much water uphill, though.

"Peak Water" and the US Southwest

Martin Blank

Tue Oct 23 21:12:50 -0700 2007

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Sort of thinking out loud here...  According to a couple of random sites I've looked at, it costs about 3.25Wh per liter to perform conventional desalination.  Based on predictions by Stirling Energy Systems, they expect their dish farm in the desert to perform at about 23.9% capacity.  They're fitting 20,000 dishes on 4500 acres, so a plot of 200 acres could handle about 850 dishes, or 4.25% of the desert plant.  This suggests about 44.5GWh of energy production per year, enough to desalinate 13.7 billion liters of water per year.

It's a depressingly low number, as it works out to about 11,100 acre-feet per year, or about 0.25% of the water drawn from the Colorado river by California annually.  It would take 20,000 acres to cover a quarter of California's water draw from the Colorado, and about 270,000 acres (about 1.2 million dishes) to cover all of the Colorado river drawdown by all states.  There's also the issue of what to do with the salt and brine that are left over.  I know that there are some interesting new developments in this field, but not at factors high enough to cover this.

It would be nice

"Peak Water" and the US Southwest

themusicgod1

Tue Oct 23 19:45:27 -0700 2007

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Water scarcity is not about not having enough water; it's not having the water where you need it, when you need it, at the right quality.  That is the hard part.  There's plenty of water in the world.  

Since it is really the bottleneck for development of life, most water is probably used.   Bacteria and photoplankton use water;  very little water on this planet is not being used at all, and most of it is probably near the poles.  You can drop a glass of water on the floor; within a day *something* will be using it.

Also;  yes there are river ecologies that would be created; but they aren't created at the same pace of what you would be destroying.  Diverting a little water at a time would be fine, but you're talking about massive redistribution that even large ecosystems would have a hard time  with; without soviet intervention, there was desert in the Aral, but it wasn't substantial;  with intervention there was a massive saline desert that was pretty much immune to life, *and* limited lifespan on the previous deserted areas(although for awhile it was productive cotton farmland).

let's take your second idea.  Putting people in the desert.

1) there's good reasons why people generally are where they are.  My current location, here in prarie saskatchewan is a good example;  ignoring the financial services sector, the work that matters most here is pulling minerals, oil, and food out of the ground.  Of course, the fuel/food/mineral sectors are not self-sufficient;  in order to have farmers survive and actually *willing* to farm, and in order to have miners mine, we keep a medial sector, service, financial services, education, woa! we have whole cities full of people doing stuff suddenly; Sure there's people who we could stand to skim off, ignoring moving-towards-singularity technology advancement, first taking the jobless, then the wasteful, the useless, and finally digging into stuff like art, manufacturing and competition; but the problem then is that the city is really lean and if anything goes wrong we'd have to import labour.  And that practically never is in the interests of the working class. But we'll assume that we're running really lean.  OK so we have a city with the absolute minnimum number of people, the rest in the desert city. What about the desert city?  We'd need raw materials -- this means transportation.  There are economies of scale putting everyone's manufacturing in one place, for sure.  But wouldn't we also be sending materials further?  Food going from extremely small towns to the desert-arcology, manufactured things from the arcology to the farmland.  I guess it would probably depend on the actual location and type of transportation(rail?)...

In other words; there is a tradeoff between building something in the place it would make sense to expecting no global warming/water scarcity, and then there is building something in the middle of the desert to minimize ecologically useful land use.

How you could *do* that would be to add a tax on every manufactured thing in areas that have the potential to support life, or tax-breaks to those who live in the desert.  Now that I put it that way, it actually makes sense.  In fact we have something like this in Canada; it's called Alberta.

salt water and food

zogger

Wed Oct 24 18:20:39 -0700 2007

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No, not nuts and doable using the correct equipment. It is already being done in israel at a ~medium~ scale. What they have is huge sealed pits filled with gravel on top of which they grow vegetables. Salt water is pumped in, and the level is always kept below what the plant's roots can reach, so there is no direct contact. Evaporation and condensation waters the roots with distilled water, nothing but the normal day night cycle is required, it just works".** Foliar feeding and limited top dressing is added to supply the necessary nutrients.

This same idea can also capture the further evaporated water, some expired by the plants, and it can be collected and then used for any normal watering purposes. Big greenhouses with drip edges more or less. I used to maintain a 4 x 8 solar water distiller for this purpose, to supply the distilled water needed for a large solar PV installation I maintained (for the batteries). It can be salt water, nasty swamp water, scrap biomass that has some moisture-most anything at all. The largest drawback is what to do with the clean-out dregs. Salt would have some value, but you might also be able to extract some minerals and metals from the salt. At best, what remains after even that could be spread out back into the oceans. Just spread out on the desert at random though, massive puimped salt water, not so good. That was the original herbicide, just dump salt where you don't want stuff to grow, kills most any normal weed or plant life pretty quickly and lasts a long time. It would also eventually leach down to any existing aquifers and contaminate them. But in sealed pits/tanks/ponds, etc., growing food or algae for biodiesel, perfectly fine to use salt water + unused desert, seems a natural. Some plants obvious will grow just fine in normal salty or brackish water, but not most terrestrial food plants.

**we use half a dozen or so earthboxes in the greenhouse here as part of what we grow, they work on exactly the same principle as the gravel pits I outlined, and they work remarkably well and have a dandy yield per square foot, I mean it's good, approaching pure hydroponics in tube systems for yield with less work. Can't recommend them enough for folks who only have an apartment with a sunny window or just limited backyard/patio/sunroom space.