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Earth Science

Is Agriculture Sucking Fresh Water Dry? 379

sciencehabit writes "The average American uses enough water each year to fill an Olympic-sized swimming pool, and global agriculture consumes a whopping 92% of all fresh water used annually. Those are the conclusions of the most comprehensive analysis to date of global water use, which also finds that one-fifth of humankind's water consumption flows across international borders as 'virtual water' — the water needed to produce a commodity, such as meat or electronics, if the ultimate consumers were to make it themselves rather than outsource its growth or manufacture."
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Is Agriculture Sucking Fresh Water Dry?

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  • by aglider ( 2435074 ) on Wednesday February 15, 2012 @06:13AM (#39042579) Homepage

    Do we actually need all those agriculture products?
    Isn't there a different way to use water for the same purpose with possibly higher efficiency?

  • by mangu ( 126918 ) on Wednesday February 15, 2012 @06:18AM (#39042593)

    Do we actually need all those agriculture products?

    Yes, we do.

    The real question is, do we need to use that much water in agriculture? As the Israeli have proved, there is much that can be done to reduce water consumption when growing plants.

  • by SeaFox ( 739806 ) on Wednesday February 15, 2012 @06:22AM (#39042607)

    The real question is, do we need to use that much water in agriculture?

    Do we need to use that much fresh water in agriculture, I wonder. A lower-level filtration process yielding "grey water" for these uses would probably be fine and save energy over a full treatment-plant supply.

  • by adolf ( 21054 ) <flodadolf@gmail.com> on Wednesday February 15, 2012 @06:29AM (#39042629) Journal

    It's just a basic business decision.

    If it's more profitable to use lots of "fresh" water than it is to reduce that water usage through different agricultural methods, then a good businessman will continue to use lots of "fresh" water.

    If the opposite becomes true, then a good businessman will adjust accordingly.

    Welcome to Capitalism.

  • by Electricity Likes Me ( 1098643 ) on Wednesday February 15, 2012 @06:53AM (#39042717)

    The problem is most water on the planet is full of salt. You can't use salt-laden "grey water" to grow things.

    You also want to take some care to ensure it's not full of heavy metals. Then there's the problem of whether other contaminants would be ignored or absorbed by plants.

    Basically, at the point where you might consider it on a large scale, it's generally just easier to use fresh or drinking quality recycled water.

  • by goombah99 ( 560566 ) on Wednesday February 15, 2012 @07:38AM (#39042913)

    Agriculture does not consume water it uses water. Virtually all the water is returned to the eco system after use.

    However there are different sources of water. Ground water versus surface water. Depletion of ground water is not sustainable as water table levels are dropping. Surface water use is sustainable but also has consequences as stream dry up as they are diverted or become filled with water so contaminated it can't be re-used down stream.

  • by l2718 ( 514756 ) on Wednesday February 15, 2012 @07:43AM (#39042925)

    Part of the problem is the traditional large subsidy that agricultural water gets (both via the infrastructure costs and in direct pricing). Farming would make better use of water if it had to pay the price.

    PS: "Olympic-size swimming pools per year" is a strange way to measure water usage. "about 6.8 cubic metres per day" is a much clearer way to express this number. In particular, this makes it clear that low-flow toilets have a negligible effect on water use compared to dishwashing, showers, etc.

  • by rtb61 ( 674572 ) on Wednesday February 15, 2012 @07:50AM (#39042949) Homepage

    Water ain't just water, water is all about how expensive it it at the point of use. How much energy is required to provide potable water at the point of use.

    The underlying corporate psychopathic distortion, is there is a lack of water. The reality is corporation want to suck up all the cheaply accessible water and then sell it at inflated prices to match the high cost of remaining water sources. Simple straight forward psychopath economics.

    Water is not too salty, too hot, too cold, too contaminated, it is just to expensive and they poor are denied access because they can not afford to potable water once they cheaply accessible resources have been consumed by greed.

    Serious about reducing water usage, where is the government mandated shift too aquaponics where possible, an agriculture system with the highest water usage efficiencies, little or no waste and the highest food ouptut per land usage.

    Where are the government demands that user pays, including corporations for the average total cost of producing water, rather than corporations have access to the cheapest charged water sources and everyone else getting charged much higher prices (total water cost should be averaged and then user pays at the average rate).

    The only difference between a clean fresh river and reverse osmosis of sea water is cost and energy consumption. The war here is access to cheap water for the majority versus corporate greed.

  • by fantomas ( 94850 ) on Wednesday February 15, 2012 @07:58AM (#39042979)

    >>Do we actually need all those agriculture products?

    >Yes, we do.

    What if we reduced our meat consumption, and reduced consumption of other water-hungry foods?

    You are of course very correct about being more efficient about water use, as proved by many people in many desert and semi-desert areas.

  • The corn farmers lobbyists are too influential in the US...
    They want to continue producing corn, and won't even consider changing their business model...
    So instead of looking to produce appropriate products to meet demand, they are looking for ways to force their existing products onto the market, even when they are not the best choice...

    Case in point high fructose corn syrup, it is a terrible sweetener and requires considerably more processing than sugar, making it more expensive to produce...
    In the US, high taxes on sugar force the use of HFCS...
    In other countries without such manipulative taxes, market forces result in sugar being used because its a more suitable product.

    The situation is so ridiculous, that people in the US actually go out of their way and often pay more to buy Coke that's been imported from Mexico because it uses real sugar instead of HFCS.

  • by ByOhTek ( 1181381 ) on Wednesday February 15, 2012 @08:20AM (#39043073) Journal

    I think by gray water, he meant partially treated sewage water.

    And, so long as the toxic stuff was clean out, maybe.

    The problems with the bacterial and fungal contaminants would still be present, and even if they were initially cleaned out, some new stuff would get in and grow - it's a good growth medium. Care would have to be used.

  • Virtual Isn't Real (Score:4, Insightful)

    by Doc Ruby ( 173196 ) on Wednesday February 15, 2012 @08:50AM (#39043233) Homepage Journal

    Water used to make a product that's shipped isn't at all necessarily water that's shipped. If the water is consumed in place but not included in the product it's not shipped. So claims that "virtual water flows across borders" is BS.

    Likewise water that's used along its natural flow path, and cleaned (enough) to return it to its original destination, is impacting only in the place where it's diverted. When we put a factory on a plot of land we disrupt that land, and we're willing to accept some deletion from nature. Nature is very resilient, and not all diversions and conversions of it have unacceptable consequences.

    We do go too far, and we do waste far too much. But exaggerations like these don't do anything except discredit the already difficult efforts to require management of what we use.

  • One of the things that goes on in permaculture is the idea of being careful about water use when growing even traditionally water-intensive crops. The idea is that you can actually do a LOT without a lot of water, and also that many mature ecosystems (including rain forests) tend to recycle a lot of their water in the form of transpiration turning into rainfall.

    So while we need a lot of water to be used in agriculture, it can be done efficiently, and with a surprisingly low level of water input even in arid environments.

  • by cbope ( 130292 ) on Wednesday February 15, 2012 @09:11AM (#39043333)

    And the OTHER real question is; why does the average American use so much water?

    As an American living abroad for nearly 12 years, I noticed a dramatic difference in water consumption after moving out of the US. Where I live in Europe (Finland), we use roughly 10-20% of what I was used to in the US. People here don't let taps run. They don't take long showers. The appliances in the home (and machines in businesses) are designed to use FAR less water than the equivalent devices in the US. My washing machine uses worst-case 10-15% of a typical US-made washing machine. Ditto for the dishwasher. Yes, the appliances and machines cost more, better engineering is required.

    When something is cheap, you don't CARE about waste. This is part of the problem with what I call the cheap-ification of America. Everything must be cheap, cheap, cheap. It is a too price-driven market. Witness the success of Walmart, which has completely destroyed large numbers of otherwise fully working businesses, all in the name of CHEAP. Let's not even get into their business practices, hiring practices and treatment of their own employees. I vowed never again to step into a Walmart and to be first in line to raise my voice should they attempt to set up shop here (luckily, they are mostly absent in the EU).

  • by Sique ( 173459 ) on Wednesday February 15, 2012 @09:18AM (#39043375) Homepage

    Not exactly. Agriculture can consume locally available water. And that's all what counts.
    If you pump water from ground depots which are not fully refilled, then most water used in agriculture ends up as clouds which the wind blows somewhere else. This water is completely lost for local use. For most of the Central U.S., the amount of water that comes in via rain or rivers, is less than the amount of water lost due to evaporation. And most of the water gets lost due to the amount of water used for agriculture. In this case, agriculture literally sucks the earth dry, because ground water, water from lakes and water enclosed in the last ice age in natural reservoirs below the surface is pumped up and evaporates. Those resources are not unlimited, and they will dry up sooner or later.
    The case is different for the East Coast or for most of Europe, where more fresh water comes in via rainfall or rivers, than gets lost due to evaporation. Here you can use as much water as you want, the resources will never dry up, you just have to make sure that used water will not intoxicate fresh water wells, so you have to build an extensive drainage system and water treatment plants.

  • by Anonymous Coward on Wednesday February 15, 2012 @10:31AM (#39044095)

    the production of 1 kg beef costs 15,500 L water the production of 1 kg broken rice costs 3,400 L water the production of 1 kg eggs costs 3,300 L water the production of 1 kg wheat costs 1,300 L water

    You vegans are worse than the religious and atheist zealots.

    Also, I seriously doubt that the net liquid cost of 1kg of cow is 15,500 L. Think about the water cycle carefully for 60 seconds (specifically, think about where cow urine and milk goes.)

  • by ArcherB ( 796902 ) on Wednesday February 15, 2012 @10:43AM (#39044237) Journal

    The AC mentioned nothing about lesbians, democrats, or mayors. All of that came out of your own biases and prejudices. The only group the AC mentioned were the religious (those who depend on "faith"), particularly those that are turning their backs on current schooling practices. Furthermore, the only thing he said about them is that they are a large proportion of the state.

    No, he mentioned the state of Texas, said "large proportion of the state depends on "faith" for their resource planning needs" and then mentioned Houston specifically. Assuming that the OP meant religion when he said faith listing Houston as an example disproves his entire point. See, the mayor of Houston is an open lesbian, and Democrat, which is exactly the group that the OP was NOT trying to blame. That's not my "own biases and prejudices". That's from CNN [cnn.com].

    I know what the OP meant. The mistake that the OP made was assuming that the red state of Texas was an all red state. Of course, all reds (conservatives) are religious too, right (yet another stereotype)? He was trying to blame the problems of Texas on the "reds" and listed a blue portion of the state as an example. I was pointing out that the OP has a "bias and prejudice" against conservatives and the religious and I used the his own evidence to disprove his case entirely and point out that he is a bigot. I guess that description includes you as well since you are so willing to blame religion for issues that religion has nothing to do with. It's kinda like the old days, when racists would blame all their problems on those damn (insert racial slur here), except you are blaming religion. If you place "Christians" in the place of "racial slur", the argument doesn't change. The level of bigotry doesn't change either.

  • by gr8_phk ( 621180 ) on Wednesday February 15, 2012 @10:46AM (#39044267)
    Most farmers do everything they can to get rain water to run off the fields so they don't flood and over-water the crops. Then they pump water out of the ground and apply it to the fields as needed. The rain water then dumps very quickly into the rivers and causes flooding down stream. A simple way to take care of this is to dig a large basin (1-2 percent the area of the fields and say 20-30 feet deep) to collect the rain water, then pump that back onto the fields as needed and only when it's dry would they need to pump water from the deep aquifer. It would help all of the problems, but would cost a bit to set up. Oh, and this would re-apply the fertilizer that washes away when it rains - which is another problem both down-stream and as a cost to farmers and a natural resource issue (phosphorous).

    All those problems come down to poor resource management.
  • by Hans Lehmann ( 571625 ) on Wednesday February 15, 2012 @11:07AM (#39044553)
    The areas in which most farming is done, i.e. out in the sticks, also have the least amount of gray water due to the low population density. The only way this idea would work was if infrastructure was built to not only partially treat the sewage and runoff from the cities, but then transport it possibly hundreds of miles to where it's most needed for agriculture.
  • by anagama ( 611277 ) <obamaisaneocon@nothingchanged.org> on Wednesday February 15, 2012 @11:54AM (#39045149) Homepage

    we could easily fix it by eating less beef -- at least beef that wasn't grass-fed.

    Not sure if that was a typo, but the researchers came to the opposite conclusion.

    From the first article:

    Another way to shrink our water footprint is to change our eating habits, Postel says. In particular, people can opt to eat less meat or to switch from grain-fed beef -- which, again, requires about 5300 liters of water for each dollar's worth of grain fed to a cow -- to grass-fed beef, which typically requires only the rainwater falling on a pasture. "Not all burgers are created equal," she says.

  • by Oligonicella ( 659917 ) on Wednesday February 15, 2012 @12:00PM (#39045209)
    "The underlying corporate psychopathic distortion, is there is a lack of water."

    Corporate? Water is typically produced by local municipalities, not corporations. Hence, your screed turns to mud. And for fuck's sake, put away the Poli-Sci 101 talk.

    "...where is the government mandated shift..." "Where are the government demands" "The war here is..."

    Socio-political bullshit.
  • by operagost ( 62405 ) on Wednesday February 15, 2012 @12:39PM (#39045699) Homepage Journal
    Other people who don't want to live, work, or otherwise cooperate with you, but want your water? And a significant percentage of them want to kill you?

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